Improved Functional Outcomes of Combined Hip Arthroscopy and Periacetabular Osteotomy at Minimum 2-Year Follow-Up

PURPOSE

To evaluate patient-reported outcomes (PROs) and survivorship at minimum 2-year follow-up after combined hip arthroscopy and periacetabular osteotomy (PAO) performed in the setting of a single anesthetic event.

METHODS

Patients who underwent combined hip arthroscopy (M.J.P.) and PAO (J.M.M.) between January 2017 and June 2020 were identified. Preoperative and minimum 2-year postoperative PROs including Hip Outcome Score-Activities of Daily Living (HOS-ADL), HOS-Sport, modified Harris Hip Score (mHHS), Western Ontario and McMaster Universities Osteoarthritis Index, 12-Item Short Form Survey Mental Component Scores (SF-12 MCS), and 12-Item Short Form Survey Physical Component Score were collected and compared in addition to revision rate, conversion to total hip arthroplasty (THA), and patient satisfaction.

RESULTS

Twenty-four of 29 patients (83%) eligible for the study were available for 2-year minimum follow-up with a median follow-up time of 2.5 years (range, 2.0-5.0). There were 19 females and 5 males with mean age of 31 ± 12 years. Mean preoperative lateral center edge angle was 20° ± 5° and alpha angle was 71° ± 11°. One patient underwent reoperation for removal of a symptomatic iliac crest screw at 11.7 months after operation. Two patients, a 33-year-old woman and a 37-year-old man, were converted to THA at 2.6 and 1.3 years, respectively, following the combined procedure. Both patients had a Tönnis grade of 1 on radiographs, as well as bipolar Outerbridge grade III/IV defects requiring microfracture of the acetabulum. For patients who did not convert to THA (n = 22), there was significant improvement from before to after surgery for all scores (P < .05) except SF-12 MCS. The minimal clinically significant difference and patient-acceptable symptom state rates for HOS-ADL, HOS-Sport, and mHHS were 72%, 82%, 86%, and 95%, 91%, and 95%, respectively. Median patient satisfaction was 10 (range, 4 to 10).

CONCLUSIONS

Single-stage combined hip arthroscopy with periacetabular osteotomy for patients with symptomatic hip dysplasia results in improvement in PROs and arthroplasty free survivorship of 92% at median 2.5 year follow-up.

LEVEL OF EVIDENCE

Level IV, case series.

Magnetic Resonance Imaging Approximates Labral Width at the 9-, 12-, and 3-O'Clock Positions in the Setting of Revision Hip Arthroscopy

PURPOSE

To compare preoperative magnetic resonance imaging (MRI) and intraoperative measurements of labral width and determine whether MRI can reliably predict labral width in the setting of revision surgery.

METHODS

Patients who underwent revision hip arthroscopy with labral repair performed by a single surgeon from January 2008 to December 2015 were identified retrospectively from a prospectively collected database. The width of the labrum was measured intraoperatively at the time of surgery. Two orthopaedic surgeons performed labral width measurements on MRI scans at 3 standardized locations using the clock-face method. Interobserver and intraobserver reliabilities were calculated, and comparisons between intraoperatively measured labral widths and MRI measurements were performed.

RESULTS

Fifty-eight patients who underwent revision hip arthroscopy were enrolled in the study. The average labral width measurements at the 3-, 12-, and 9-o'clock positions were 7.4 mm (standard deviation [SD], 1.2 mm), 7.5 mm (SD, 1.4 mm), and 6.6 mm (SD, 1.2 mm), respectively, on MRI compared with 6.7 mm (SD, 2.1 mm), 6.5 mm (SD, 2.5 mm), and 7.0 mm (SD, 1.9 mm), respectively, when measured intraoperatively. The average intraoperative measurements were smaller than the MRI measurements at the 3-o'clock (P = .03) and 12-o'clock (P = .01) positions. The inter-rater intraclass correlation coefficients between the 2 surgeons exhibited good agreement (0.612) at the 3-o'clock position, fair agreement (0.498) at the 12-o'clock position, and poor agreement (0.171) at the 9-o'clock position. The positive predictive values of the MRI measurements were 72% at the 3-o'clock position, 68% at the 12-o'clock position, and 88% at the 9-o'clock position for identifying a labral width of 6 mm or greater.

CONCLUSIONS

The results of this study show that MRI-measured labral width and actual labral width measured at the time of revision arthroscopy are usually within 1 mm of each other.

LEVEL OF EVIDENCE

Level II, diagnostic study investigating diagnostic test.

Effect of osteophyte removal on simulated range of motion using 3-dimensional preoperative planning software for reverse total shoulder arthroplasty

Background

Glenohumeral osteophytes (OPs) can adversely influence postoperative range of motion (ROM) following shoulder arthroplasty due to mechanical impingement. Though commercial three-dimensional preoperative planning software (3D PPS) is available to simulate ROM before and after OP resection, little is known about the magnitude of effect OPs and their subsequent removal have on simulated glenohumeral ROM.

Methods

Included patients were 1) indicated for reverse total shoulder arthroplasty (rTSA) using 3D PPS and 2) presented with glenoid and/or humeral head OPs on preoperative two-dimensional computed tomography (2D-CT) imaging. Thirty patients met the inclusion criteria (9 females, 21 males; mean age 70.45 ± 4.99 years, range 63-80 years). All subjects (n = 30) presented with humeral OPs (mean volume: 2905.16 mm3, range 109.1-11,246 mm3), while 11 subjects also presented with glenoid OPs (mean volume 108.06 mm3, range 37.59-791.4 mm3). Preoperative CTs were used to calculate OP volume (mm3) and OP circumferential extent (clockface). Mean clockface position for circumferential humeral OPs originated at 6:09 (range 4:30-7:15) and extended to 8:51 (range 8:15-10:15). Mean clockface position for glenoid OPs originated at 3:00 (range 2:00-5:00) and extended to 6:16 (range 3:00-7:30). 3D implants on PPS were standardized to achieve 0° of version, 0° of inclination and 4 mm of net lateralization. Thirty-nine and thirty-six mm glenospheres were used for males and females, respectively. 3D PPS was used to evaluate simulated ROM differences before and after OP removal in the planes of adduction (ADD), abduction, internal rotation (IR), external rotation (ER), extension, and flexion. Impact of OP volume and circumferential extent on pre and postop removal ROM were also analyzed.

Results

Humeral OP removal significantly increased impingement-free ADD, IR, ER, extension, and flexion. Removal of larger (mm3) humeral OPs positively correlated with improvement in IR (R = 0.452, P = .011), ER (R = 0.394, P = .033), and flexion (R = 0.500, P < .01). Greater circumferential extent of humeral OPs correlated with worse preremoval ROM in the planes of ADD (R = 0.364, P = .02) and extension (R = 0.403, P = .04), and improvements in ER postop removal (R = 0.431, P = .03).

Conclusion

Humeral OP removal significantly increases impingement-free ADD, IR, ER, extension, and flexion in simulated 3D PPS models following rTSA. Magnitude of simulated ROM improvement is influenced by initial humeral OP volume and circumferential clockface extent. Surgeons should consider these effects when using 3D PPS for rTSA planning to optimize postoperative ROM prognostics.

Timing From Symptom Onset to Hip Arthroscopy Does Not Affect Patient-Reported Outcome Measures for the Treatment of Femoroacetabular Impingement in Adolescent Patients

PURPOSE

To evaluate symptom duration and its relationship to patient-reported outcomes (PROs) and survivorship after hip arthroscopy in adolescents.

METHODS

Patients ≤18 at time of primary hip arthroscopy for femoroacetabular impingement (FAI) between January 2011 and September 2018 were included. Exclusion criteria consisted of history of previous ipsilateral hip surgery, presence of osteoarthritis or dysplasia on preoperative radiographs, previous hip fracture, or history of slipped capital femoral epiphysis or Legg-Calve-Perthes disease. Minimum 2-year PROs (modified Harris Hip Score, Hip Outcome Score [HOS]-Activities of Daily Living, HOS-Sport Scale, Short Forms 12 [SF-12]), minimum clinically significant difference (MCID) and patient-acceptable symptom state (PASS) rates, and revision surgery rates were compared based on symptom duration.

RESULTS

Two-year minimal follow-up was obtained for 111 patients (134 hips) (80%), including 74 females and 37 males with a mean age of 16.4 ± 1.1 (range 13.0-18.0). The mean symptom duration was 17.2 ± 15.2 months (range 43 days to 6.0 years). Ten patients (11 hips), 6 females (7 hips) and 4 males, required revision surgery at an average of 2.3 ± 1.0 years (range 0.9-4.3 years). At a mean follow-up of 4.8 ± 2.2 years (range 2-10 years), there were statistically significant improvements in all PROs (P < .05 for all). Symptom duration showed no significant correlation to post-operative scores (correlation coefficient range -0.162 to -0.078, P > .05 for all). Symptom duration ≤12 months versus >12 months or as a continuous variable was not a predictor for requiring revision surgery or achieving MCID/PASS (95% confidence interval crosses 1 for all).

CONCLUSIONS

In an adolescent cohort of symptomatic FAI patients who underwent hip arthroscopy, there is no difference in PRO measures when analyzing symptom duration by arbitrary time intervals or as a continuous variable.

LEVEL OF EVIDENCE

Level IV, case series.

Adhesions in the setting of hip arthroscopy

With the growing number of primary arthroscopies performed, patients requiring revision hip arthroscopies for various issues is high including postoperative adhesion formation, a source of pain, mechanical symptoms, range of motion limitation, stiffness, and microinstability. Adhesions are a consequence of biological pathways that have been stimulated by injury or surgical interventions leading to an increased healing response. Preventative efforts have included surgical adjuncts during/after primary hip arthroscopy, biologic augmentation, and postoperative rehabilitation. Treatment options for adhesion formation includes surgical lysis of adhesions with or without placement of biologic membranes aimed at inhibiting adhesion reformation as well as systemic medications to further reduce the risk. Postoperative rehabilitation exercises have also been demonstrated to prevent adhesions as a result of hip arthroscopy. Ongoing clinical trials are further investigating pathways and prevention of adhesion formation.

Kinematic and Kinetic Comparisons of Arm Slot Position Between High School and Professional Pitchers

Background

Throwing arm kinetics differ in pitchers at varying arm slot (AS) positions (frontal-plane arm position at ball release relative to the vertical axis).

Purpose

To determine how kinematic and kinetic values differ between professional and high school pitchers with varying AS positions, and whether these differences are similarly observed in both populations.

Methods

High school (n = 130) and professional (n = 288) pitchers threw 8 to 12 fastballs under 3-dimensional motion capture technology. Pitchers in each cohort were subdivided based on mean AS position at ball release: AS1 (least degree of AS: most overhand throwing styles), AS2 (intermediate degree of AS: three-quarter throwing styles), or AS3 (greatest degree of AS: most sidearm throwing styles). Kinetic and kinematic parameters were compared between groups.

Study Design

Controlled laboratory study.

Results

High school pitchers had a more overhand AS at ball release (50° ± 11°) compared with professional pitchers (58° ± 14°) (P < .001). In both cohorts, AS1 pitchers had significantly greater shoulder abduction (high school, P <0.001; professional, P <0.0001) and lateral trunk flexion (high school, P < 0.001; professional, P <0.0001) at ball release compared with AS3 pitchers. Professional pitchers with an AS3 position had significantly delayed timing of maximum upper trunk angular velocity compared with AS1 pitchers (64% ± 7% vs 57% ± 7% of pitch time, respectively; P < .0001). A significant positive correlation between AS and elbow flexion torque was found in high school pitchers (P = .002; β = 0.28), and a significant negative correlation between AS and elbow varus torque (P < .001; β = -0.22) and shoulder internal rotation torque (P < .001; β = -0.20) was noted in professional pitchers.

Conclusion

AS position was related to shoulder abduction and trunk lateral tilt. Professional and high school pitchers with varying AS positions did not experience similar changes in throwing arm kinetics.

Clinical Relevance

In professional pitchers, the earlier onset of maximum upper trunk angular velocity with overhand throwing style may reflect inappropriate pelvis-trunk timing separation, a parameter implicated in upper extremity injury, and the negative correlation between AS and elbow varus and shoulder internal rotation torque suggests that both excessive and minimal AS positions have negative implications.

Correlation of Acromial Morphology With Risk and Direction of Shoulder Instability: An MRI Study

BACKGROUND

The influence of bony morphology on the development of posterior shoulder instability is not well known.

PURPOSE

To determine if acromial morphology, as measured on magnetic resonance imaging (MRI), is associated with posterior or anterior shoulder instability.

DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

MRI measurements of posterior acromial coverage (PAC), posterior acromial height (PAH), posterior acromial tilt (PAT), and anterior acromial coverage (AAC) were completed for 3 separate matched groups who underwent surgical intervention: posterior instability, anterior instability, and a comparison group of patients who underwent arthroscopic surgery for snapping scapula. Inclusion criteria were patients with recurrent instability <40 years of age without multidirectional instability, glenoid bone loss >13.5%, or glenoid retroversion >10%.

RESULTS

Overall, 37 patients were included in each group. PAC was significantly less in the posterior instability group than in the anterior instability and comparison groups (68.3° vs 88.7° vs 81.7°; P < .001). PAH was significantly greater in the posterior group than in the anterior instability group (11.0 mm vs -0.1 mm; P < .001) and comparison group (0.7 mm; P < .001). There was no difference between the posterior and anterior groups in terms of PAT or AAC (P = .45 and P = .05, respectively). PAT was significantly smaller in the posterior instability group than the comparison group (55.2° vs 62.2°; P = .026). The anterior and comparison groups were not significantly different in PAH or PAT (P = .874 and P = .067, respectively) but were significantly different in AAC (P = .026).

CONCLUSION

A higher and flatter posterior acromion, as measured on preoperative MRI, appears to be associated with patients who require arthroscopic capsulolabral repair due to posterior shoulder instability. This information may help clinicians to both diagnose and predict the need for operative intervention for patients with posterior labral tears.

The revision hip arthroscopy complex: capsular deficiency, labral deficiency, femoral over-resection and adhesions can result in good survivorship with revision hip arthroscopy

To evaluate the patient-reported outcomes (PROs) and survivorship of combined arthroscopic hip labral reconstruction/augmentation, capsular reconstruction, femoral neck remplissage and lysis of adhesions. Patients ≥18 years old who underwent this combination of procedures during revision hip arthroscopy and were eligible for minimum 2-year follow-up were identified. PRO scores including Hip Outcome Score (HOS)-Activities of Daily Living scale, HOS-Sports scale, modified Harris Hip Score, Short Form 12, and Western Ontario & McMaster Universities Osteoarthritis Index, patient satisfaction and failure rates were analyzed. Seven patients (5 females and 2 males) with average age of 45.0 ± 5.2 (range: 40-54 years) met inclusion criteria. Patients had a median of 1 (range: 1-3) prior hip surgery at an outside institution. All patients had previously undergone femoral osteoplasty, and 85% (6/7) of patients had a labral repair performed. Four patients had no capsule closure performed in their prior procedures. Six patients were available for minimum 2-year follow-up. Two patients converted to total hip arthroplasty: one patient with four prior hip arthroscopies and the other had advanced osteoarthritis with outerbridge grade 3/4 defects requiring microfracture. Mean patient satisfaction was 7 (range: 2-9). At mean follow-up of 3 years, most patients who underwent the combination of labral reconstruction, capsular reconstruction, femoral neck remplissage and lysis of adhesions during revision hip arthroscopy demonstrated improved PROs. This salvage procedure has the potential to restore hip function in patients who have failed an initial hip arthroscopy procedure. In patients with these pathologies present and concomitant joint space narrowing, a total hip arthroplasty may be a more appropriate salvage option.

The Relationship Between the Joint Space and Outcomes After Hip Arthroscopic Surgery for Femoroacetabular Impingement: Reevaluating the 2-mm Rule

BACKGROUND

A limited joint space (<2 mm) is associated with poorer outcomes and conversion to total hip arthroplasty (THA) after hip arthroscopic surgery. As indications for hip arthroscopic surgery expand, it is important to reevaluate established risk factors among large patient populations.

PURPOSE

To reevaluate the relationship between the radiographic joint space and outcomes after hip arthroscopic surgery and to assess the validity of a joint space of 2 mm as the accepted cutoff for successful hip arthroscopic surgery.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients aged 18 to 50 years who underwent hip arthroscopic surgery for femoroacetabular impingement between January 2008 and December 2016 and had a minimum 2-year follow-up were included. Patients with previous ipsilateral hip surgery, a history of hip fractures, dysplasia (lateral center-edge angle <20°), or osteoarthritis (Tonnis grade >2) were excluded. The joint space was categorized as diminished (≤2 mm), borderline (>2 to ≤3 mm), or preserved (>3 mm). Minimum 2-year patient-reported outcomes (modified Harris Hip Score [mHHS], Hip Outcome Score-Activities of Daily Living [HOS-ADL], Hip Outcome Score-Sports-Specific Subscale [HOS-SSS]), revision rates, and rates of conversion to THA were compared between groups.

RESULTS

A total of 699 patients (782 hips) with a mean age of 33.8 ± 10.1 years met 2-year inclusion criteria. The mean follow-up time was 4.2 ± 2.1 years. Overall, 51 hips (6.5%) had a diminished joint space, 297 (38.0%) had a borderline joint space, and 434 (55.5%) had a preserved joint space. Patients with a diminished joint space had larger femoral and acetabular defects compared with those with larger joint spaces. All groups had improved patient-reported outcome scores compared with baseline (P < .001 for all), and there were no differences between the groups in the percentage of patients who reached the minimal clinically important difference or patient acceptable symptom state. There were also no differences between the groups in revision rates (P = .95). A greater number of hips with a diminished joint space converted to THA (n = 8 [15.7%]) compared with those with a borderline (n = 9 [3.0%]) or preserved (n = 9 [2.1%]) joint space (P < .001). Considering joint space as a continuous variable, adjusted logistic regression showed that for every millimeter decrease in the joint space, the odds of conversion to THA increased by a factor of 2.5 (odds ratio, 2.5 [95% CI, 1.6-3.8]).

CONCLUSION

This study demonstrated that patients with a diminished joint space were at a higher risk of conversion to THA. Although 2 mm should not serve as a strict cutoff, patients should be counseled based on their preoperative radiographic findings accordingly.

Outcomes for Treatment of Capsulolabral Adhesions With a Capsular Spacer During Revision Hip Arthroscopy

BACKGROUND

The presence of adhesions is a common source of pain and dysfunction after hip arthroscopic surgery and an indication for revision surgery. The placement of a capsular spacer in the capsulolabral recess after lysis of adhesions has been developed to treat and prevent the recurrence of adhesions.

PURPOSE

To evaluate patient-reported outcomes (PROs) and survivorship at a minimum of 2 years after revision hip arthroscopic surgery with capsular spacer placement for capsular adhesions.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Between January 2013 and June 2018, a total of 95 patients (99 hips) aged ≥18 years underwent revision hip arthroscopic surgery for the treatment of capsular adhesions with the placement of a capsular spacer. Overall, 53 patients (56 hips) met the inclusion criteria and had a minimum 2-year follow-up, forming the cohort of this study. Exclusion criteria included confounding metabolic bone diseases (eg, Legg-Calve-Perthes disease, Marfan syndrome), labral deficiency, or advanced osteoarthritis (Tönnis grade 2 or 3). Preoperative and postoperative outcome scores (modified Harris Hip Score [mHHS], Hip Outcome Score-Activities of Daily Living [HOS-ADL], Hip Outcome Score-Sport-Specific Subscale [HOS-SSS], 12-Item Short Form Health Survey [SF-12], and Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC]) were collected and compared in addition to the revision rate, conversion to total hip arthroplasty, and patient satisfaction.

RESULTS

The mean age of the cohort was 32 ± 11 years, with 32 female hips (57%) and a median number of previous hip arthroscopic procedures of 1 (range, 1-5). The arthroplasty- and revision-free survivorship rate at 2 years was 91%. Overall, 5 patients (6 hips; 11%) underwent revision surgery at a mean of 2.4 ± 1.4 years after capsular spacer placement, with symptomatic capsular defects being the most common finding. There were 4 patients (7%) who converted to total hip arthroplasty. For hips not requiring subsequent surgery (n = 46), there was a significant improvement in outcome scores except for the SF-12 Mental Component Summary, with rates of achieving the minimal clinically important difference of 70%, 70%, and 65% for the mHHS, HOS-ADL, and HOS-SSS, respectively.

CONCLUSION

Capsular spacers, as part of a systematic approach including lysis of adhesions with early and consistent postoperative physical therapy including circumduction exercises, resulted in improved PROs as well as high arthroplasty- and revision-free survivorship (91%) at a minimum 2-year follow-up. Capsular spacers should be considered in revision hip arthroscopic procedures when an adequate labral volume remains but adhesions continue to be a concern.

MRL/MpJ Mice Resist to Age-Related and Long-Term Ovariectomy-Induced Bone Loss: Implications for Bone Regeneration and Repair

Osteoporosis and age-related bone loss increase bone fracture risk and impair bone healing. The need for identifying new factors to prevent or treat bone loss is critical. Previously, we reported that young MRL/MpJ mice have superior bone microarchitecture and biomechanical properties as compared to wild-type (WT) mice. In this study, MRL/MpJ mice were tested for resistance to age-related and long-term ovariectomy-induced bone loss to uncover potential beneficial factors for bone regeneration and repair. Bone tissues collected from 14-month-old MRL/MpJ and C57BL/6J (WT) mice were analyzed using micro-CT, histology, and immunohistochemistry, and serum protein markers were characterized using ELISAs or multiplex assays. Furthermore, 4-month-old MRL/MpJ and WT mice were subjected to ovariectomy (OV) or sham surgery and bone loss was monitored continuously using micro-CT at 1, 2, 4, and 6 months (M) after surgery with histology and immunohistochemistry performed at 6 M post-surgery. Sera were collected for biomarker detection using ELISA and multiplex assays at 6 M after surgery. Our results indicated that MRL/MpJ mice maintained better bone microarchitecture and higher bone mass than WT mice during aging and long-term ovariectomy. This resistance of bone loss observed in MRL/MpJ mice correlated with the maintenance of higher OSX⁺ osteoprogenitor cell pools, higher activation of the pSMAD5 signaling pathway, more PCNA⁺ cells, and a lower number of osteoclasts. Systemically, lower serum RANKL and DKK1 with higher serum IGF1 and OPG in MRL/MpJ mice relative to WT mice may also contribute to the maintenance of higher bone microarchitecture during aging and less severe bone loss after long-term ovariectomy. These findings may be used to develop therapeutic approaches to maintain bone mass and improve bone regeneration and repair due to injury, disease, and aging.

Arthroscopic Core Decompression for Avascular Necrosis of the Femoral Head Using Multiple Small-Diameter Tunnels

Avascular necrosis of the femoral head (AVNFH) is a debilitating disease that requires early intervention to prevent subchondral collapse and irreversible damage leading to premature hip replacement. Patients presenting with AVNFH can have concomitant intra-articular pathology, including femoroacetabular impingement (FAI), that contributes to their hip pain and dysfunction. It is important to restore the native hip anatomy in addition to providing revascularization of necrotic areas to reduce pain, improve function, and maximize efforts to preserve the joint. The purpose of this Technical Note is to describe our preferred arthroscopic approach to core decompression through the femoral neck in combination with femoral osteoplasty to address AVNFH and FAI in a single-staged and minimally invasive procedure.

Effect of Anchor Density on Functional Outcomes After Arthroscopic Hip Labral Repair

BACKGROUND

While labral repair has been widely adopted as the first line treatment for labral injury during hip arthroscopy, there is no widespread consensus on the procedural technique, including the number of anchors that should be used to avoid recurrent instability and revision surgery.

PURPOSE

To determine if anchor density can predict patient-reported outcomes after arthroscopic labral repair in the hip.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients aged 18 to 50 years who underwent primary hip arthroscopic surgery with labral repair between January 2011 and December 2016 were identified from a prospectively collected database. Exclusion criteria consisted of previous ipsilateral surgery, osteoarthritis (Tönnis grade >1), and severe cartilage defects (Outerbridge grade III/IV) or concomitant labral reconstruction, capsular reconstruction, or microfracture. Minimum 2-year patient-reported outcomes (modified Harris Hip Score [mHHS], Hip Outcome Score [HOS]-Activities of Daily Living [ADL], HOS-Sport Specific Subscale [SSS], 12-Item Short Form Health Survey [SF-12]), rates of achieving the minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) for each score, revision surgery rate, and rate of conversion to total hip arthroplasty (THA) were compared based on anchor density (number of anchors per millimeter of labral tear).

RESULTS

A total of 634 hips (575 patients) with a mean age of 30.4 ± 9.5 years (range, 18.0-49.9 years) met inclusion criteria. The mean labral tear size was 31 ± 11 mm (range, 2-70 mm) with a median number of anchors used for labral repair of 3 (range, 1-7) and mean anchor density of 0.11 ± 0.08 anchors (range, 0.03-1.33) per millimeter of labral tear. Hips with a minimum 2-year follow-up (451/634 [71.1%]) had significant improvements on the mHHS, HOS-ADL, HOS-SSS, and SF-12 Physical Component Summary (P < .001 for all). There was no significant correlation detected between anchor density or number of anchors used and postoperative scores (correlation coefficient range, -0.05 to 0.17; P > .05 for all). The rate of revision surgery was 6.4% (28 patients), with 8 hips found to have labral tears and/or deficiency on revision. Additionally, 6 hips (1.3%) had to undergo THA at a mean of 3.6 ± 2.1 years (range, 2.0-5.5 years).

CONCLUSION

Anchor density did not have a correlation with postoperative outcomes, achieving the MCID or PASS, revision hip arthroscopic surgery, complications, or conversion to THA.

The influence of excessive ipsilateral trunk tilt on upper-extremity throwing mechanics: a newly characterized parameter for biomechanical evaluation in high school and professional pitchers

BACKGROUND

Although contralateral trunk tilt has been recognized, the phenomenon of excessive ipsilateral trunk tilt, often observed during earlier portions of the pitch, has not been explored as a potential correlate with throwing-arm kinetics among baseball pitchers. The purpose of this study was to evaluate kinetic and kinematic parameters among high school and professional pitchers related to excessive ipsilateral and contralateral trunk tilt.

METHODS

Professional and high school pitchers were assessed with a 3-dimensional motion capture system (480 Hz) while pitching. Pitchers were grouped as follows: excessive ipsilateral tilt at foot contact (FC), neutral, or excessive contralateral tilt at ball release (BR). Trunk and shoulder kinematics as well as throwing-arm kinetics were compared between subgroups via post hoc regression analysis.

RESULTS

Professional pitchers (n = 287) had significantly higher ipsilateral trunk tilt at FC (P < .001) than high school pitchers (n = 59). High school pitchers with excessive contralateral trunk tilt at BR experienced significantly higher shoulder superior force (27.0% ± 7.4% body weight [BW] vs. 17.6% ± 5.1% BW, P < .001) and shoulder anterior force (39.6% ± 8.2% BW vs. 35.7% ± 5.4% BW, P < .001) compared with the ipsilateral trunk tilt cohort but had comparable ball velocity (30.2 ± 3.2 m/s vs. 30.4 ± 2.1 m/s, P = .633). For professionals, for every 10° increase in ipsilateral trunk tilt at FC, ball velocity increased by 0.2 m/s (B = 0.02, β = 0.07, standard error [SE] = 0.005, P = .010) whereas elbow varus torque decreased by 0.1% BW × height (B = -0.01, β = -0.08, SE = 0.002, P < .001) and shoulder internal rotation torque decreased by 0.1% BW × height (B = -0.01, β = -0.07, SE = 0.002, P = .005).

CONCLUSION

High school and professional pitchers with excessive ipsilateral trunk tilt at FC consistently demonstrated significantly decreased throwing-arm kinetics (shoulder anterior force and shoulder superior force for high school pitchers and shoulder internal rotation torque and elbow varus torque for professional pitchers) compared with pitchers with excessive contralateral trunk tilt at BR, with equivalent ball velocity. In addition, professional pitchers appeared to engage in significantly greater ipsilateral trunk tilt during early portions of the pitch when compared with high school pitchers, which may represent a kinetically favorable method adopted by pitchers at higher playing levels to maintain adequate ball velocity while concomitantly minimizing throwing-arm kinetics.

The use of heparin/polycation coacervate sustain release system to compare the bone regenerative potentials of 5 BMPs using a critical sized calvarial bone defect model

Nonunion following bone fracture and segmental bone defects are challenging clinical conditions. To combat this clinical dilemma, development of new bone tissue engineering therapies using biocompatible materials to deliver bone growth factors is desirable. This aim of this study is to use a heparin/polycation coacervate sustained-release platform to compare 5 bone morphogenetic proteins (BMPs) for promoting bone defect healing in a critical sized calvarial defect model. The in vitro 3D osteogenic pellet cultures assays demonstrated that BMPs 2, 4, 6, 7 and 9 all enhanced mineralization in vitro compared to the control group. BMP2 resulted in higher mineralized volume than BMP4 and BMP6. All BMPs and the control group activated the pSMAD5 signaling pathway and expressed osterix (OSX). The binding of BMP2 with coacervate significantly increased the coacervate average particle size. BMP2, 4, 6, & 7 bound to coacervate significantly increased the Zeta potential of the coacervate while BMP9 binding showed insignificant increase. Furthermore, using a monolayer culture osteogenic assay, it was found that hMDSCs cultured in the coacervate BMP2 osteogenic medium expressed higher levels of RUNX2, OSX, ALP and COX-2 compared to the control and BMPs 4, 6, 7 & 9. Additionally, the coacervate complex can be loaded with up to 2 μg of BMP proteins for sustained release. In vivo, when BMPs were delivered using the coacervate sustained release system, BMP2 was identified to be the most potent BMP promoting bone regeneration and regenerated 10 times of new bone than BMPs 4, 6 & 9. BMP7 also stimulated robust bone regeneration when compared to BMPs 4, 6 & 9. The quality of the newly regenerated bone by all BMPs delivered by coacervate is equivalent to the host bone consisting of bone matrix and bone marrow with normal bone architecture. Although the defect was not completely healed at 6 weeks, coacervate sustain release BMPs, particularly BMP2 and BMP7, could represent a new strategy for treatment of bone defects and non-unions.

Preoperative Magnetic Resonance Imaging Predicts Intraoperative Labral Width at the 9-O’clock and 12-O’clock Positions in Primary Hip Arthroscopy

Purpose

To determine whether preoperative magnetic resonance imaging (MRI) can reliably predict labral width in primary hip arthroscopy.

Methods

Patients who underwent primary hip arthroscopy with labral repair performed by a single surgeon from January 2008 to December 2015 were identified retrospectively from a prospectively collected database. The width of the labrum was measured intraoperatively at the time of surgery. Two orthopaedic surgeons performed labral width measurements on MRI at 3 standardized locations using the clock-face method at 2 time points, 4 weeks apart. Interobserver and intraobserver reliabilities were calculated, and comparisons were performed between intraoperatively measured labral widths and MRI measurements at the 3 positions.

Results

Fifty-eight patients who underwent primary hip arthroscopy were enrolled in the study. The average labral width measurements at the 3-, 12-, and 9-o’clock positions were 6.8 mm (standard deviation [SD], 1.1), 6.9 mm (SD, 1.3 mm), and 6.2 mm (SD, 0.9 mm), respectively, on MRI compared with 7.2 mm (SD, 1.5 mm), 7.8 mm (SD, 2.3 mm), and 7.3 mm (SD, 1.6 mm), respectively, when measured intraoperatively. The intraoperative measurements were larger than the MRI measurements at all 3 locations, with significant differences at the 12-o’clock (P = .008) and 9-o’clock (P < .001) positions. The positive predictive value of the MRI measurements was 92% at the 3-o’clock position, 89% at the 12-o’clock position, and 94% at the 9-o’clock position for identifying a labral width of 6 mm or greater.

Conclusions

Measuring labral width on MRI yielded, on average, a value that is smaller than the intraoperatively measured width in primary hip arthroscopy procedures. MRI can predict a labral width of 6 mm or greater in at least 89% of cases, which will assist in operative planning.

Clinical Relevance

The clinical implications of this research include identifying the rare patients in whom more advanced hip arthroscopy procedures may be indicated, such as labral augmentation, in instances of inadequate labral volume that will adequately restore the biomechanics of the suction seal.

Evaluating Pelvis Rotation Style at Foot Contact: A Propensity Scored Biomechanical Analysis in High School and Professional Pitchers

BACKGROUND

Early pelvis rotation has been associated with decreased throwing arm kinetics and conventionally was considered a component of proper pitching form in baseball throwers. However, previous assessments of pelvis rotation style have not accounted for confounders such as playing level, anthropometric characteristics, or ball velocity and have not evaluated sufficient sample sizes.

PURPOSE

To compare kinetic and kinematic parameters based on pelvis rotation style in high school and professional pitchers.

STUDY DESIGN

Descriptive laboratory study.

METHODS

High school and professional baseball pitchers threw 8 to 12 fastball pitches while being evaluated using 3-dimensional motion capture (480 Hz). These pitchers were 1:1 propensity score matched by age, height, weight, handedness, and ball velocity based on early (<60°) versus late (≥60°) pelvis rotation style at foot contact. A total of 26 kinematic and 10 kinetic parameters were compared between groups. The kinematic parameters were used to conduct a linear regression between early and late pelvis rotation at foot contact.

RESULTS

Pelvis rotation at foot contact was not significantly associated with ball velocity for either high school (P = .243) or professional pitchers (P = .075). No difference was found in elbow varus torque between high school early rotators (57.5 ± 14.9 N·m) and late rotators (51.3 ± 14.7 N·m; P = .036) and between professional early rotators (80.1 ± 11.8 N·m) and late rotators (79.0 ± 11.2 N·m; P = .663). At foot contact in high school pitchers, stride length increased by 2.1% of body height (B = -0.205; β = -0.470; P < .001), trunk rotation increased by 4.2° (B = -0.417; β = -0.488; P < .001), and trunk flexion at foot contact decreased by 4.4° (B = 0.442; β = 0.476; P < .001) with every 10° increase in pelvis rotation. At foot contact in professional pitchers, stride length increased by 2.3% of body height (B = -0.229; β = -0.478; P < .001), trunk rotation increased by 4.3° (B = -0.431; β = -0.515; P < .001), and trunk flexion decreased by 4.0° (B = 0.404; β = 0.373; P < .001) with every 10° increase in pelvis rotation.

CONCLUSION

Pelvis rotation at foot contact was associated with several kinematic parameters in both groups and may influence mechanics further along the kinetic chain. Landing open or closed was not significantly associated with throwing arm kinetics or ball velocity for both high school and professional baseball pitchers, contrary to previous thought.

CLINICAL RELEVANCE

Coaches and players may better focus their efforts on refining other kinematic parameters for enhanced performance outcomes and safe pitching mechanics.

Arthroscopic Hip Capsular Reconstruction Using Iliotibial Band Allograft as a Salvage Option for Unrepairable Capsular Defects Demonstrates Good Survivorship and Improved Patient-Reported Outcomes

PURPOSE

To describe patient outcomes 3 to 5 years after arthroscopic hip capsule reconstruction.

METHODS

Between January 2007 and December 2016, patients aged 18 to 50 years who underwent arthroscopic hip capsular reconstruction using an Iliotibial band allograft by the senior author and had minimum of 3-year follow-up were identified. Patients were excluded if they had previous open hip surgery, advanced osteoarthritis (Tönnis grade >2), significant acetabular dysplasia (lateral center edge angle <20°), avascular necrosis, or Legg-Calve-Perthes disease. Outcome scores including the Hip Outcome Score (HOS)-Activities of Daily Living scale, modified Harris Hip Score, HOS-Sports scale, SF-12, and Western Ontario & McMaster Universities Osteoarthritis Index were compared in addition to failure rate, revision rate, and patient satisfaction rate with the outcome (range, 1-10). All patients were assessed by the senior author pre- and postoperatively.

RESULTS

Thirty-nine patients met the inclusion criteria. The mean age of the cohort was 32 ± 10 years, with 6 male and 33 female patients. The average number of previous hip arthroscopy surgeries was 2 ± 1. Six patients (15%) converted to total hip arthroplasty at an average of 2.1 years (range 7 months to 6 years) following capsular reconstruction. Four patients required revision hip arthroscopy after the arthroscopic capsular reconstruction. All arthroscopic revisions occurred in female patients with the primary intraoperative finding of capsulolabral adhesions at the time of revision. At mean follow-up of 4.3 years (range 3-6.8 years), the 29 patients who did not require subsequent surgery had significant improvements from preoperatively to postoperatively in HOS-Activities of Daily Living and HOS-Sport with 90% reaching minimal clinically important difference. All other scores showed significant improvement. Survival for patients not requiring total hip arthroplasty was 86% at 3 years, with a mean survival of 5.7 years (95% confidence interval 4.97-6.4).

CONCLUSIONS

Arthroscopic hip capsular reconstruction with iliotibial band allograft is a successful treatment option for patients with symptomatic capsular defects, demonstrating improved patient-reported outcomes maintained at mean follow-up time of 4 years. This technique offers restoration of the anatomic structure and function of the capsular ligaments to improve pain and instability.

LEVEL OF EVIDENCE

IV, case series.

Surgical Treatment of Acetabular Dysplasia With Labral Tears

Acetabular dysplasia results in abnormal forces across the hip joint and can result in both labral tears and cartilage degeneration. A continuum exists from classic dysplasia to normal acetabular morphology. Diagnosis is aided by several radiographic measurements and parameters including a lateral center edge angle of less than 20°, an anterior center edge angle of less than 20°, a Sharp's angle of greater than 42°, and a Tonnis angle of greater than 10°, or version abnormalities. When patients with acetabular dysplasia present with intra-articular hip pain, skeletal maturity, and preserved radiographic joint space, a periacetabular osteotomy (PAO) is considered as a surgical treatment option when conservative measures have failed. The Bernese PAO was developed in 1984 as a way for reorienting the acetabulum to restore more normal femoral head coverage and orientation. The long-term results of this procedure have been promising with 10-year and 20-year survivorships of approximately 85% and 60%, respectively. When dysplasia is coupled with a labral tear or other intra-articular pathology including focal chondral damage, ligamentum teres tears, or capsular defects, hip arthroscopy and PAO are performed. Although there is a paucity in the literature of the long-term evidence for the combined procedure, early results indicate improved patient reported outcome measures. Appropriate treatment of borderline hip dysplasia remains controversial.

Effects of oral losartan administration on homeostasis of articular cartilage and bone in a rabbit model

Background and aims

Previous work has shown that oral losartan can enhance microfracture-mediated cartilage repair in a rabbit osteochondral defect injury model. In this study, we aimed to determine whether oral losartan would have a detrimental effect on articular cartilage and bone homeostasis in the uninjured sides.

Methods

New Zealand rabbits were divided into 4 groups including normal uninjured (Normal), contralateral uninjured side of osteochondral defect (Defect), osteochondral defect plus microfracture (Microfracture) and osteochondral defect plus microfracture and losartan oral administration (10 mg/kg/day) (Losartan). Rabbits underwent different surgeries and treatment and were sacrificed at 12 weeks. Both side of the normal group and uninjured side of treatment groups tibias were harvested for Micro-CT and histological analysis for cartilage and bone including H&E staining, Herovici's staining (bone and cartilage) Alcian blue and Safranin O staining (cartilage) as well as immunohistochemistry of losartan related signaling pathways molecules for both cartilage and bone.

Results

Our results showed losartan oral treatment at 10 mg/kg/day slightly increase Alcian blue positive matrix as well as decrease collagen type 3 in articular cartilage while having no significant effect on articular cartilage structure, cellularity, and other matrix. Losartan treatment also did not affect angiotensin receptor type 1 (AGTR1), angiotensin receptor type 2 (AGTR2) and phosphorylated transforming factor β1 activated kinase 1 (pTAK1) expression level and pattern in the articular cartilage. Furthermore, losartan treatment did not affect microarchitecture of normal cancellous bone and cortical bone of tibias compared to normal and other groups. Losartan treatment slightly increased osteocalcin positive osteoblasts on the surface of cancellous bone and did not affect bone matrix collagen type 1 content and did not change AGTR1, AGTR2 and pTAK1 signal molecule expression.

Conclusion

Oral losartan used as a microfracture augmentation therapeutic does not have significant effect on uninjured articular cartilage and bone based on our preclinical rabbit model. These results provided further evidence that the current regimen of using losartan as a microfracture augmentation therapeutic is safe with respect to bone and cartilage homeostasis and support clinical trials for its application in human cartilage repair.

Outcomes and Survivorship at a Median of 8.9 Years Following Hip Arthroscopy in Adolescents with Femoroacetabular Impingement: A Matched Comparative Study with Adults

BACKGROUND

Because of the unique theoretical surgical risks, including osteonecrosis, acute iatrogenic slipped capital femoral epiphysis, and epiphyseal injury, the optimal treatment strategy for femoroacetabular impingement (FAI) in growing adolescents has yet to be established. The aim of this study was to compare the clinical outcomes of primary arthroscopic treatment of FAI in growing adolescents with a matched adult group.

METHODS

Patients with FAI who underwent arthroscopic treatment with a minimum follow-up of 2 years were included. Patients with previous ipsilateral hip surgery, an Outerbridge grade of ≥3, a preoperative Tönnis grade of ≥2, or evidence of dysplasia (lateral center-edge angle of <25°) were excluded. Eligible patients who were ≤19 years old and whose proximal femoral physis had not yet closed were matched to adult (20 to 40-year-old) counterparts in a 1:1 ratio by sex, body mass index, and time of surgery. For the adolescents, cam resection was performed with a physeal-sparing approach. Outcome scores, including the modified Harris hip score (mHHS), Hip Outcome Score-Activities of Daily Living (HOS-ADL), and HOS-Sports-Specific Subscale (HOS-SSS), were prospectively collected.

RESULTS

Of the 196 eligible adolescents, 157 (80%) were pair-matched to adult controls, with a median postoperative follow-up of 8.9 and 6.6 years, respectively. Fourteen (9%) of the adolescents required revision hip arthroscopy compared with 18 adults (11%) (p = 0.46). No patient in the adolescent group had conversion to a total hip arthroplasty (THA), while 3 in the adult group had a THA (p = 0.25). For adolescents without subsequent hip surgery, the median mHHS improved from 59 preoperatively to 96 postoperatively; the HOS-ADL, from 71 to 98; and the HOS-SSS, from 44 to 94 (p < 0.001), which were significantly higher postoperative scores than those of the matched adults (p < 0.05) despite similar or inferior baseline scores. No complications were found during the office visit or at the final follow-up.

CONCLUSIONS

Hip arthroscopy performed with a physeal-sparing approach for FAI in growing adolescents is safe and effective and yields superior clinical outcomes compared with those in a matched adult group.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Increased Knee and Meniscal Injury Incidence in Professional Baseball Pitchers With Wider, Positive Stride Width

BACKGROUND

Professional baseball pitchers sustain 75% of knee injuries while at the pitcher's mound, yet no pitching motion has been associated directly with such injuries. Stride width is a potential, modifiable risk factor worth investigating.

HYPOTHESIS

Increased stride width in both the positive and negative directions (deviations from neutral stride width) would correlate with increased incidence of knee injury in pitchers.

STUDY DESIGN

Descriptive laboratory.

LEVEL OF EVIDENCE

Level 5.

METHODS

Professional pitchers (n = 199) were evaluated with motion capture (480 Hz) while pitching. Injury history over 10 years was recorded at face-to-face interviews with pitchers. Players were subsequently grouped into stride width tertiles, compared for previous injury incidence of the lower extremities. Regressions were performed to observe performance benefits of stride width with ball velocity, accuracy, or consistency in pitch location as secondary outcomes.

RESULTS

Of the 40 lower extremity injuries reported, meniscal injury (27.5%) was the most common, followed by foot stress fracture (20.0%). Significant differences in injury incidence were noted between the least and most positive stride width tertiles: lower extremity (10.4% vs 25.8%, respectively; P = 0.03), knee (3.0% vs 15.2%, respectively; P = 0.02), and meniscal (0.0% vs 12.1%; P = 0.00). Stride width of pitchers with meniscal injury in the lead (32.6 ± 7.1 cm, n = 5; P = 0.02) and stance leg (33.5 ± 10.6 cm, n = 5; P = 0.03) was significantly more positive than that of uninjured pitchers (21.1 ± 11.5 cm, n = 164). No significant relationships were established between stride width and ball velocity (P = 0.54) or pitch location metrics (P > 0.05).

CONCLUSION

Pitchers with increased positive, stride width had significantly higher incidence of lower extremity injury (knee and meniscus). Wider, positive stride width may increase the degree of external rotation on the lead knee in a loaded state, which can place the medial side of the knee (and meniscus) at higher risk of injury.

CLINICAL RELEVANCE

Decreasing stride width may be beneficial for professional pitchers to reduce the rate of lower extremity injury, while also preserving performance metric outcomes.

Management of Complex and Revision Anterior Shoulder Instability

Treatment of recurrent anterior shoulder instability has gained significant interest in recent years and involves evaluation of both glenoid and humeral sided bone loss. Decision making is more complex in patients with significant humeral or glenoid bone defects or in those who underwent previous instability surgery. Appropriate assessment of the glenoid track is necessary as "off track" lesions typically require treatments beyond arthroscopic labral repair alone. In those with significant humeral or glenoid sided bone loss, the authors recommend three-dimensional computed tomography in addition to magnetic resonance imaging for accurate evaluation. The Glenoid Track Instability Management Score is a useful guide to help direct treatment by using the glenoid track as well as other known risk factors for recurrence. In circumstances with significant glenoid bone loss, typically over 20%, a coracoid transfer such as the Latarjet is recommended. In patients that previously failed a coracoid transfer, the authors recommend a distal tibia allograft; however, distal clavicle and iliac crest autograft have also been reported to have high success rates. In those with large Hill-Sachs lesions, remplissage or bone grafting are recommended. An estimation of the postoperative glenoid track after glenoid bone augmentation is required for appropriate Hill-Sachs lesion treatment. The authors typically recommend against revision instability surgical treatment with arthroscopic repair alone.

Outcomes of Arthroscopic Anterior Labroligamentous Periosteal Sleeve Avulsion Lesions: A Minimum 2-Year Follow-up

BACKGROUND

Anterior labroligamentous periosteal sleeve avulsion (ALPSA) lesions can occur in recurrent anterior shoulder instability, which may lead to the labrum scarring medially to the glenoid. ALPSA lesions have also been associated with greater preoperative dislocations, larger Hill-Sachs lesions, and greater degrees of glenoid bone loss. Therefore, patients with these lesions have historically had a higher failure rate after repair, with nearly double the recurrent instability rate compared with those undergoing standard arthroscopic Bankart repair.

PURPOSE

To compare minimum 2-year outcomes of arthroscopic mobilization and anatomic repair of ALPSA lesions with those after standard arthroscopic Bankart repair.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Consecutive patients who underwent arthroscopic repair of ALPSA lesions were matched in a 1-to-3 fashion to patients who underwent standard Bankart repair by age, sex, number of previous ipsilateral shoulder instability surgical procedures, and number of anchors used. Patient-reported outcome (PRO) scores were compared preoperatively and postoperatively (American Shoulder and Elbow Surgeons [ASES]; 12-Item Short Form Health Survey [SF-12] Physical Component Summary [PCS]; Single Assessment Numeric Evaluation [SANE]; shortened version of Disabilities of the Arm, Shoulder and Hand; and satisfaction). Recurrent instability, on- versus off-track Hill-Sachs lesion, and reoperation rates were analyzed.

RESULTS

A total of 100 shoulders (25 ALPSA and 75 Bankart) with an overall mean age of 25.7 years were evaluated. Patients in the ALPSA group demonstrated significant improvements in the ASES (preoperative, 74.8; postoperative, 89.7; P = .041) and SF-12 PCS (preoperative, 46.9; postoperative, 53.4; P = .021) scores but not the SANE score (preoperative, 65.2; postoperative, 75.3; P = .311). Patients in the Bankart group had significant improvements in all outcome scores at final follow-up: ASES (preoperative, 67.1; postoperative, 90.3), SANE (preoperative, 58.0; postoperative, 85.7), and SF-12 PCS (preoperative, 45.3; postoperative, 52.9) (all P < .001). There were no significant differences in PRO scores between the groups preoperatively or postoperatively (P > .05). The median satisfaction for the ALPSA group was 10 of 10 and for the Bankart group it was 9 of 10 (P = .094). There was a significantly higher rate of recurrent dislocation in the ALPSA group (8/25 [32.0%]) compared with the Bankart group (10/75 [13.3%]) (P = .040). Additionally, 5 patients (20.0%) in the ALPSA group underwent revision surgery at a mean of 5.6 years, and 8 patients (10.7%) in the Bankart group underwent revision surgery at a mean of 4.4 years (P = .311).

CONCLUSION

Despite improvements in the recognition of and surgical techniques for ALPSA lesions, they still lead to significantly higher postoperative dislocation rates; however, no differences in PRO scores were found. These findings highlight the importance of early surgical interventions in anterior shoulder instability with the hope of lessening recurrent instability and the risk of developing an ALPSA lesion, as well as careful assessment of the quality of soft tissues and other risk factors for recurrence when considering what type of shoulder stabilization procedure to perform.

Minimum 2-Year Clinical Outcomes of Medial Meniscus Root Tears in Relation to Coronal Alignment

BACKGROUND

The effect of coronal plane alignment on the outcomes of repairs of the medial meniscus root remains unclear.

HYPOTHESIS

Increased preoperative varus alignment is associated with higher failure rates and lower patient-reported outcomes (PROs) after isolated repair of the medial meniscus root.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients aged 18 years or older who underwent arthroscopy-assisted repair of the medial posterior meniscus root over a 7-year period were included. The mechanical axis of the knee was measured preoperatively. Osteoarthritis was assessed radiographically preoperatively and at the final follow-up according to the Kellgren-Lawrence grading scale. Failure was defined as any patient having to undergo revision root repair, partial meniscectomy of the previously repaired meniscus, debridement, lysis of adhesions, or conversion to arthroplasty.

RESULTS

A total of 53 patients (29 women, 24 men) with a mean age of 51.3 years were included in the follow-up analysis. The mean time of follow-up after surgery was 3.3 years (range, 22-77 months). Significant improvements were observed in all PROs analyzed. Decreased varus as measured by alignment percentage was correlated with baseline Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain (P = .023) and WOMAC Stiffness (P = .022). Alignment percentage was also significantly negatively correlated with postoperative WOMAC Stiffness (P = .005) and positively correlated with Lysholm (P = .003) and International Knee Documentation Committee (P = .009) scores. Higher baseline Kellgren-Lawrence grade was correlated with worse postoperative PROs (P < .05), except 12-Item Short Form Health Survey Mental Component Summary and satisfaction. Eight patients who underwent a concomitant high tibial osteotomy (HTO) achieved lower PROs in all scales analyzed, regardless of their alignment. When excluding patients who underwent HTO, postoperative Lysholm score (P = .004) and postoperative WOMAC Stiffness (p = 0.014) were inferior among the patients with >5° of varus.

CONCLUSION

Lower extremity alignment closest to neutral correlated with improved PROs. Patients who underwent a concurrent HTO had worse PROs than those who did not undergo HTO.

Open Fixation of Displaced Greater Tuberosity Fractures Yields Similar Patient-Reported Outcomes to Acute Arthroscopic Rotator Cuff Repair at 2 Years: A Matched Cohort Analysis

Purpose

To evaluate and compare patient-reported outcomes (PROs) after isolated greater tuberosity (GT) fracture fixation versus acute rotator cuff repair (RCR) at a minimum of 2 years.

Methods

Patients who underwent isolated GT fracture fixation were compared in a 1-to-3 fashion with patients who underwent arthroscopic RCR for an acute rotator cuff tear by a single surgeon from January 2006 and to July 2018. Data were prospectively collected and retrospectively reviewed. PROs were compared pre- and postoperatively as well as between groups (American Shoulder and Elbow Surgeons [ASES], General Health Short Form-12 Physical Component [SF-12 PCS], Single Assessment Numerical Evaluation [SANE], Quick Disabilities of the Arm, Shoulder, and Hand [QuickDASH], and satisfaction). Reoperation rates were analyzed.

Results

A total of 57 patients (14 with isolated GT fracture fixation, mean age 45.7 years; and 43 who underwent ARCR for acute tears, mean age 56.6 years) were evaluated (P = .050). ASES scores significantly improved from 39.7 to 94.1 (P = .018) in the isolated GT fracture fixation group and from 51.0 to 95.2 (P < .001) in acute RCR group. At final follow-up, mean QuickDASH scores were 8.9 and 7.9 (P = .677) and SANE scores were 91.1 and 87.3 (P = .616) for the GT and acute RCR groups, respectively. The median satisfaction was 10/10 for the GT group and 10/10 for the RCR group. Additional comparison of patients who underwent double-row repair for an acute rotator cuff tear or isolated GT fracture revealed no significant difference in outcomes (P > .404).

Conclusion

Minimum 2-year PROs after fixation of isolated GT fractures show relatively high outcome scores whether treated by open reduction and internal fixation or arthroscopic fixation using a double-row bridging technique. The improvements in PROs are similar to those achieved with acute rotator cuff tears that were fixed arthroscopically with RCR. Further analysis of these results suggest that the functional outcomes of tendon-to-bone healing with linked, double-row rotator cuff repairs are similar to those of bone-to-bone healing as seen with GT fractures.

Level of Evidence

III, retrospective comparative study.

Midterm Outcomes After Hip Labral Augmentation in Revision Hip Arthroscopy

BACKGROUND

Labral augmentation has emerged as an essential procedure to address a deficient or irreparable labrum while preserving native labral tissue and restoring the hip suction seal mechanism.

PURPOSE

To evaluate midterm outcomes of arthroscopic hip labral augmentation for labral insufficiency after previous hip arthroscopy.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients were identified from a prospectively collected database who underwent arthroscopic hip labral augmentation between January 2011 and January 2017 with a minimum 3-year follow-up. Pre- and postoperative patient-reported outcome scores were compared and included the 12-Item Short Form Health Survey physical and mental component summaries, Western Ontario and McMaster Universities Osteoarthritis Index, modified Harris Hip Score (mHHS), and Hip Outcome Score (HOS) (Activities of Daily Living [ADL] and Sport). Postoperative Tegner Activity Scale and patient satisfaction (1-10) scores were also evaluated. The minimal clinically important difference (MCID) and Patient Acceptable Symptom State (PASS) between the preoperative and minimum 3-year follow-up scores were calculated.

RESULTS

A total of 88 patients (39 men, 49 women) underwent revision hip arthroscopy with labral augmentation. The average age was 32.8 ± 11 years. Of these, 77 patients (88%) were available for the minimum 3-year follow-up. The survivorship (absence of conversion to total hip arthroplasty) at 3 years and 5 years was 93% at both time points, with a mean survival time of 8.5 years (95% CI, 8.0-8.9). Eleven patients (14%) required revision arthroscopic surgery for continued pain. Revisions occurred at a mean of 2.6 ± 1.4 years after augmentation. The mean follow-up was 5.2 ± 1.2 years (range, 3-9 years). For patients not requiring subsequent surgery (n = 61), all patient-reported outcome measures significantly improved, which included a 20-point increase in HOS-ADL (MCID, 82%; PASS, 72%) and mHHS (MCID, 78%; PASS, 70%). The median postoperative Tegner score was 4 (range, 1-10). The median postoperative patient satisfaction score was 9 out of 10 (range, 1-10).

CONCLUSION

Arthroscopic hip labral augmentation is a successful treatment option for patients with labral insufficiency after previous hip arthroscopy, demonstrating improved patient-reported outcomes and survivorship of 93% at 3 years and 5 years. This technique provides a valuable labral preservation option when addressing hip labral pathology when viable native labral tissue remains.

Arthroscopic Characterization, Treatment, and Outcomes of Glenoid Labral Articular Disruption Lesions

BACKGROUND

The pathoanatomy of glenoid labral articular disruption (GLAD) lesions has been inconsistently and poorly defined in the literature.

PURPOSE/HYPOTHESIS

The purpose was to characterize GLAD lesions as they pertain to the pathoanatomy of labrum, cartilage, and bony structures, and to correlate findings with patient-reported outcomes (PROs). We hypothesized that greater degrees of bony and cartilaginous involvement would correlate with worse outcomes.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

All patients with a diagnosis of a GLAD lesion or a reverse GLAD (RGLAD) lesion at the time of diagnostic arthroscopy (January 2006-February 2019) were included in this study. Patients with ≥13.5% bone loss or previous ipsilateral shoulder surgery were excluded. Patient charts and operative reports/photos were used to identify the location of injury, extent of injury (labral, chondral, and bony), associated injuries, demographic factors, and treatment performed. Three injury patterns were identified: small (type 1), with no chondral defect after labral repair; large (type 2), with residual chondral defect after labral repair; and bony (type 3), with associated glenoid bone loss amenable to labral repair. Characterizations were cross-referenced to PROs at a mean follow-up of 5.5 years (range, 2.6-10.5 years): American Shoulder and Elbow Surgeons (ASES), Single Assessment Numeric Evaluation, shortened version of Disabilities of the Arm, Shoulder and Hand, and patient satisfaction.

RESULTS

In total, 50 patients were included, with 40 having GLAD and 10 having RGLAD lesions (mean age, 34.7 and 33.2 years, respectively). There were 14 (35%) type 1, 22 (55%) type 2, and 4 (10%) type 3 GLAD injuries. All PROs improved without any differences in the 3 subgroups postoperatively (ASES, 95.1 vs 91.3 vs 98.8, type 1, 2, and 3, respectively). RGLAD injuries were majority type 2 (7/10; 70%) with the remainder being type 1 (3/10; 30%).

CONCLUSION

With GLAD and RGLAD injuries, 3 distinct injury patterns can be observed correlating with the presence/absence of chondral loss after labral repair or the presence of associated bone loss. This descriptive characterization can facilitate arthroscopic treatment decisions. Future large studies are needed to determine if this is prognostic in nature.

Comprehensive Arthroscopic Management of Shoulder Arthritis

Glenohumeral arthritis is a challenging problem, especially in the young, active patient. After nonoperative treatment, including activity modification, anti-inflammatory medications, physical therapy, and injections, is exhausted, surgical treatment ranging from simple debridement to arthroplasty is commonly offered. Given concerns regarding arthroplasty implant longevity, there is an interest in joint-preserving procedures. In this difficult population, the authors recommend a systematic, inclusive approach to the array of pathologies encountered in the setting of early glenohumeral arthritis: the Comprehensive Arthroscopic Management (CAM) procedure. CAM consists of the combination of arthroscopy, glenohumeral chondroplasty, synovectomy, loose body removal, microfracture, capsular release, humeral osteoplasty, axillary nerve neurolysis, subacromial decompression, and biceps tenodesis. Key perioperative care includes the use of regional nerve blocks to allow immediate physical therapy with the goal of restoring range of motion by 4 to 6 weeks with strengthening beginning at 6 to 12 weeks and return to full activities at 4 to 6 months. Although this is still considered a bridging procedure, the literature has reported 92% survival at 1 year, 85% survival at 2 years, 77% survival at 5 years, and 63% survival at 10 years. Predictors of failure of the CAM procedure include joint space <2 mm, flattening of the humeral head, and abnormal posterior glenoid morphology. Patient selection and education is therefore essential for optimizing outcomes.

Arthroscopic Subcoracoid Decompression, Coracoplasty, and Subscapularis Repair for Subscapularis Tears in the Setting of Subcoracoid Impingement

Subscapularis tears have been found to occur in the setting of subcoracoid impingement and are related to the narrowing of the coracohumeral interval. The advancement of arthroscopic techniques has allowed for improved identification and treatment of this historically overlooked pathology. Challenges of arthroscopic subscapularis treatment include nearby neurovascular structures, tendon retraction, and adhesions, which are further complicated by diminished arthroscopic visualization, resulting from the concomitant subcoracoid impingement. The purpose of this Technical Note is to describe our preferred technique for arthroscopic management of subscapularis tears in the setting of subcoracoid impingement that is simple and reproducible, as well as cost-effective and efficient with limited additional morbidity to that of a standard diagnostic shoulder arthroscopy.

Shoulder Pathology on Magnetic Resonance Imaging in Asymptomatic Elite-Level Rock Climbers

Background:

The prevalence of findings on shoulder magnetic resonance imaging (MRI) is high in asymptomatic athletes of overhead sports.

Purpose/Hypothesis:

The purpose of this study was to determine the prevalence of atypical findings on MRI in shoulders of asymptomatic, elite-level climbers and to evaluate the association of these findings with clinical examination results. It was hypothesized that glenoid labrum, long head of the biceps tendon, and articular cartilage pathology would be present in >50% of asymptomatic athletes.

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

A total of 50 elite climbers (age range, 20-60 years) without any symptoms of shoulder pain underwent bilateral shoulder examinations in addition to dedicated bilateral shoulder 3-T^† MRI. Physical examinations were performed by orthopaedic sports medicine surgeons, while MRI scans were interpreted by 2 blinded board-certified radiologists to determine the prevalence of abnormalities of the articular cartilage, glenoid labrum, biceps tendon, rotator cuff, and acromioclavicular joint.

Results:

MRI evidence of tendinosis of the rotator cuff, subacromial bursitis, and long head of the biceps tendonitis was exceptionally common, at 80%, 79%, and 73%, respectively. Labral pathology was present in 69% of shoulders, with discrete labral tears identified in 56%. Articular cartilage changes were also common, with humeral pathology present in 57% of shoulders and glenoid pathology in 19% of shoulders. Climbers with labral tears identified in this study had significantly increased forward elevation compared with those without labral tears in both active (P = .026) and passive (P = .022) motion.

Conclusion:

The overall prevalence of intra-articular shoulder pathology detected by MRI in asymptomatic climbers was 80%, with 57% demonstrating varying degrees of glenohumeral articular cartilage damage. This high rate of arthritis differs significantly from prior published reports of other overhead sports athletes.

Outpatient Joint Arthroplasty: Practical Guidelines for Success, Effect of COVID--19, and the Roles of Technology and Partnering With Industry

The COVID-19 pandemic has had a drastic effect on the landscape of outpatient joint arthroplasty. By accelerating the migration to ambulatory surgery centers and hospital outpatient departments, protocols and techniques had to adapt quickly. In addition, the roles of technology and partnering with industry became more appealing in some cases to address specific voids and needs during this transition period. The COVID-19 pandemic abruptly affected the state of outpatient joint arthroplasty in 2020 with long-lasting effects that will continue to shape the practice of outpatient total joint arthroplasty for years to come.

Systematic Review of Platelet-Rich Plasma for Rotator Cuff Repair: Are We Adhering to the Minimum Information for Studies Evaluating Biologics in Orthopaedics?

Background

The therapeutic efficacy of orthobiologic therapies for rotator cuff repair is difficult to evaluate owing to reporting inconsistences. In response, the Minimum Information for Studies Evaluating Biologics in Orthopaedics (MIBO) guidelines were developed to ensure standard reporting on orthobiologic therapies.

Purpose

To systematically review clinical studies evaluating platelet-rich plasma (PRP) for full-thickness rotator cuff repair and adherence to MIBO guidelines.

Study Design

Scoping review; Level of evidence, 4.

Methods

A search was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using PubMed, EMBASE, and the Cochrane Library databases. Inclusion criteria were clinical studies reporting on rotator cuff tears (≥1 cm) surgically repaired with PRP. Patient demographics, biologic intervention, and adherence to the MIBO guidelines were systematically reviewed.

Results

A total of 19 studies (1005 patients) were included in this review. Across all studies, 58.5% of the MIBO checklist items for PRP were reported. Out of 47 checklist items, 19 were reported in over 85% of studies, whereas 22 were reported in less than half of studies. Details of whole-blood processing and characteristics, as well as PRP processing and characteristics, were reported inconsistently, and no study provided adequate information to enable the precise replication of preparation protocols for PRP.

Conclusion

This systematic review highlights the current reporting deficiencies within the scientific literature of important variables for evaluating PRP for full-thickness rotator cuff repair. There was widespread variability among published studies that evaluate PRP for this application and, more specifically, studies were limited by inconsistent universal reporting of whole-blood and PRP processing and postprocessing characteristics. To improve our understanding of biologic efficacy and to promote repeatability, stricter adherence to the MIBO guidelines is necessary. We propose that the checklist limitations be addressed and that modification of the MIBO guidelines be considered to improve the reporting of individual components within certain categories.

Anchor Arthropathy of the Shoulder Joint After Instability Repair: Outcomes Improve With Revision Surgery

PURPOSE

To report clinical and patient-reported outcome measures (PROMs) in patients undergoing revision surgery after diagnosis of anchor-induced arthropathy.

METHODS

Patients who underwent revision arthroscopic shoulder surgery and were diagnosed with post-instability glenohumeral arthropathy performed from January 2006 to May 2018 were included in the current study. Patients were excluded if they underwent prior open shoulder procedures, if glenoid bone loss was present, or if prerevision imaging and records were incomplete or not available. Data included initial diagnosis and index procedure performed, presenting arthropathy symptoms including duration, exam findings before revision surgery, and surgical intervention. PROMs were prospectively collected before surgery and at minimum 2-year follow-up.

RESULTS

Fourteen patients were included with a mean (± standard deviation) age at presentation of 35.2 ± 12.1 years (range 16 to 59). The follow-up rate was 86%, with a mean follow-up of 3.8 years (range 1.1 to 10.6). Mean time to development of arthropathy symptoms was 48.2 months (range <1 month to 13.8 years), all presenting with pain and decreased range of motion on exam. At time of revision surgery, all patients underwent either open or arthroscopic removal of previous implants, including anchors and suture material. Six patients underwent additional revision stabilization procedures, 1 underwent total shoulder arthroplasty, and 7 underwent arthroscopic intraarticular debridement, capsular release, and chondroplasty with or without microfracture. Pain significantly improved in 79% of patients (P = .05). Significant improvements in all PROMs were observed, including 12-item Short Form (43.8 to 54.8, P < .01); Disabilities of the Arm, Shoulder, and Hand, shortened version (31.8 to 8.4, P < .01); Single Assessment Numeric Evaluation (47.0 to 84.5, P < .05); and American Shoulder and Elbow Surgeons (61.6 to 92.1, P < .01). Average external rotation significantly improved, from 31° ± 22° to 52° ± 24° (P = .02).

CONCLUSION

Rapid intervention after diagnosis, through either revision arthroscopic or open debridement and stabilization, can lead to significant improvement in range of motion, pain, and overall patient function and satisfaction.

LEVEL OF EVIDENCE

IV, retrospective case series.

Intra- versus inter-pitcher comparisons: Associations of ball velocity with throwing-arm kinetics in professional baseball pitchers

BACKGROUND

The association between ball velocity and elbow varus torque has shown differences when evaluated within a single pitcher and within a cohort. The impact of increasing ball velocity on additional throwing-arm kinetics, in particular shoulder distraction forces, with intra- vs. inter-pitcher evaluations has not been evaluated, even though these kinetic measures have been implicated in injury risk. The purpose of this study was to compare intra- vs. inter-pitcher relationships between ball velocity and all major kinetics at the shoulder and elbow in professional pitchers.

METHODS

A total of 323 professional baseball pitchers threw 8-12 fastball pitches while simultaneously being evaluated with 3-dimensional motion-capture technology (480 Hz). A linear regression analysis was performed to evaluate pitch velocity as a predictor of peak kinetic values at the shoulder and elbow among pitchers. A linear mixed model with random intercepts was then created to evaluate ball velocity as a predictor of peak kinetic values when comparing pitches within an individual pitcher.

RESULTS

91 pitchers were included in the analyses. Ball velocity among pitchers had weak correlations with shoulder distraction force (R² = 0.228, P < .001) and elbow distraction force (R² = 0.175, P < .001). Within an individual pitcher, strong correlations (R² > 0.85) were observed for (1) shoulder internal rotation torque (P < .001), (2) shoulder horizontal adduction torque (P = .006), (3) shoulder superior force (P < .001), (4) shoulder anterior force (P < .001), (5) elbow varus torque (P < .001), (6) elbow medial force (P < .001), (7) elbow anterior force (P < .001), (8) elbow flexion torque (P < .001), (9) shoulder distractive force (P < .001), and (10) elbow distractive force (P < .001).

CONCLUSION

Faster pitch velocity is a weak predictor of shoulder and elbow distraction forces experienced among professional pitchers. However, when controlling for an individual pitcher, peak kinetics at the shoulder and elbow can be strongly predicted by ball velocity. Therefore, the assumption that higher peak throwing-arm kinetic values are experienced by pitchers with faster ball velocity is likely an inappropriate assumption among pitchers but may be correct for each player who increases pitch velocity.

Autograft Versus Allograft: The Evidence in Hip Labral Reconstruction and Augmentation

BACKGROUND

Labral augmentation and labral reconstruction have emerged as essential procedures for restoring the anatomic and functional characteristics of the hip joint in patients with a deficient hip labrum or irreparable labral tear.

HYPOTHESIS/PURPOSE

The purpose of this study was to compare allograft and autograft hip labral reconstruction and augmentation. We hypothesized that autografts would entail fewer revision arthroscopic procedures.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients were identified who underwent labral reconstruction or labral augmentation using iliotibial band (ITB) allograft or ITB autograft performed by a single surgeon between 2011 and 2017. Patient-reported outcome measures collected before surgery and at minimum 2-year follow-up included the following: Hip Outcome Score Activities of Daily Living and Hip Outcome Score Sports-Specific Subscale and, at follow-up, patient satisfaction (range, 1-10, with 10 being very satisfied). Patients followed a standardized rehabilitation protocol after surgery with relative individualization to address each patient's needs. For continuous variables, comparisons between allografts and autografts were made using Student t tests or Mann-Whitney tests. Categorical comparisons were assessed using chi-square or Fisher exact test. Multiple logistic regression was performed to determine the influence of graft choice on risk of revision or THA.

RESULTS

A total of 205 hips met 2-year inclusion criteria. ITB allografts were used for 55 patients (37 augmentations, 18 reconstructions) and ITB autografts for 150 patients (34 augmentations, 116 reconstructions). Females represented a greater proportion of allograft versus autograft patients (71% vs 46%, respectively; P = .001). Overall, autograft patients had larger alpha angles (66.6° vs 59.1°; P = .001) and longer grafts (46 vs 41 mm; P = .03) compared with allograft patients. A total of 13 (23.6%) patients required revision surgery in the allograft group compared with 11 (7.3%) in the autograft group (P < .001). After controlling for sex, procedure (reconstruction vs augmentation), and previous surgery, the odds of revision were higher for allograft patients (OR, 4.1; 95% CI, 1.5-11.6). No significant differences in conversion to THA were observed between groups (allograft = 9%; autograft = 6%; P = .50), even after adjustment for the above covariates (OR, 2.3; 95% CI, 0.6-7.9). No differences in postoperative patient-reported outcome measures or patient satisfaction were observed between groups.

CONCLUSION

Labral augmentation or reconstruction with autograft has a significantly lower revision rate than labral augmentation or reconstruction with allograft.

Grade III Acromioclavicular Separations Treated With Suspensory Fixation Techniques: A Systematic Review of Level I Through IV Studies

Purpose

To perform a systematic review comparing clinical outcomes, radiographic outcomes, and complication rates after acute (surgery ≤6 weeks from injury) versus chronic (surgery >6 weeks from injury) acromioclavicular joint reconstructions for grade III injuries using modern suspensory fixation techniques.

Methods

We performed a systematic review of the literature examining acute versus chronic surgical treatment of Rockwood grade III acromioclavicular joint separations using the Cochrane registry, MEDLINE database, and Embase database over the past 10 years according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines. The inclusion criteria included techniques using suspensory fixation, a minimum study size of 3 patients, a minimum follow-up period of 6 months, human studies, and English-language studies. The methodology of each study was evaluated using the Methodological Index for Non-randomized Studies (MINORS) tool for nonrandomized studies and the revised Cochrane risk-of-bias (RoB 2) tool for randomized controlled trials.

Results

The systematic review search yielded 20 studies with a total of 253 patients. There were 2 prospective randomized controlled trials, but most of the included studies were retrospective. On comparison of acute surgery (≤6 weeks) and chronic surgery (>6 weeks), individual studies reported a range of Constant scores of 84.4 to 98.2 and 80.8 to 94.1, respectively. The ranges of radiographic coracoclavicular distances reported at final follow-up also favored acute reconstructions, which showed improved reduction (9.2-15.7 mm and 11.7-18.6 mm, respectively). The reported complication rates ranged from 7% to 67% for acute reconstructions and from 0% to 30% for chronic reconstructions.

Conclusions

The ranges in the Constant score may favor acute reconstructions, but because of the heterogeneity in the surgical techniques in the literature, no definitive recommendations can be made regarding optimal timing.

Level of Evidence

Level IV, systematic review of Level I through IV studies.

Arthroscopic Labral Repair Using Knotless Suture Anchors in the Setting of a 270° Labral Tear of the Shoulder

Extensive glenoid labral tears, whether the result of repetitive instability or first-time dislocation, compromise the mechanical stability of the glenohumeral joint due to disruption of the anterior, inferior, posterior, and/or superior portions of the labrum. These lesions often result in recurrent multiplanar instability and pain that is nonresponsive to conservative management and difficult to diagnose due to variability in clinical presentation and advanced imaging findings. Arthroscopic repair techniques to address symptomatic shoulder instability have showed positive patient-reported outcomes, low failure rates, and high return-to-sport rates. The evolution of knotless suture anchors offers a fixation method that has proven to be functionally equivalent to knotted suture anchors while avoiding the risks of knotted anchors (knot loosening, knot migration, articular abrasion) and allowing easier placement and decreased operative time. The purpose of this technique is to describe our preferred method to treat a 270° labral tear through arthroscopic knotless anchor repair and demonstrate the expanded application of this technique for extensive glenoid labral pathology.

Does dual plating clavicle fractures increase the risk of refracture after hardware removal? A biomechanical investigation

BACKGROUND

Dual orthogonal plating of midshaft clavicle fractures is increasingly used for osteosynthesis. The risk of refracture after hardware removal remains unknown. The purpose of this study was to compare the torsional and 3-point bending loads to failure of the clavicle following removal of single-plane, superior 3.5-mm plate fixation vs. dual orthogonal plating 2.7-mm constructs.

METHODS

This study used 12 pairs of clavicles (N = 24) harvested from cadaveric specimens with a mean age at death of 56.5 years (range, 46-65 years). One clavicle from each pair was randomly assigned to either superior plating (SP, n = 12) or double plating (DP, n = 12). For SP, a superior 3.5-mm plate was used as a template to drill 3 bicortical 2.8-mm holes medial and lateral to the center of the clavicle. For DP, two 2.7-mm plates were used as a template to drill 4 bicortical 2.0-mm holes medial and lateral to the center of the clavicle. Clavicle pairs were randomly and evenly distributed to undergo either 3-point bending (n = 12) or posterior torsional loading (n = 12). Cyclic loading was performed, followed by load-to-failure testing. Stiffness, displacement at failure, load to failure, and failure mode were assessed and compared between SP and DP constructs.

RESULTS

No significant differences between the SP and DP groups were observed for stiffness (768.2 ± 281.3 N/mm vs. 785.5 ± 315.0 N/mm, P = .872), displacement at failure (8.1 ± 2.8 mm vs. 5.4 ± 1.2 mm, P = .150), and ultimate load at failure (1831.0 ± 229.6 N vs. 1842.0 ± 662.4 N, P = .964) under the condition of 3-point bending. Similarly, no significant differences between the SP and DP groups were observed for torsional stiffness (1.3 ± 0.8 N · m/° vs. 1.1 ± 0.4 N · m/°, P = .844), rotation at failure (17.3° ± 4.4° vs. 14.4° ± 1.2°, P = .205), and ultimate torque at failure (14.8 ± 6.5 N · m vs. 14.7 ± 6.9 N · m, P = .103) under the condition of posterior torsional loading. The most common mode of failure for 3-point bending testing was an oblique fracture (7 of 12 clavicles, 58.3%), with no significant difference between groups (3 of 6 in SP group [50%] vs. 4 of 6 in DP group [66.7%], P > .999). The most common mode of failure with posterior torsional loading was a spiral fracture (10 of 12 clavicles, 83.3%), with no significant difference between groups (4 of 6 in SP group [66.7%] vs. 6 of 6 in DP group [100%], P = .455).

CONCLUSION

Following clavicle plate removal of either DP or SP, there is no statistically significant difference in the amount of force, under the condition of 3-point bending or torsional loading, required to fracture the diaphyseal clavicle in vitro.

Salvage Revision Hip Arthroscopy Including Remplissage Improves Patient-Reported Outcomes After Cam Over-Resection

PURPOSE

To evaluate outcomes of arthroscopic hip remplissage with folded iliotibial band allograft to treat cam over-resection.

METHODS

Patients who underwent arthroscopic iliotibial band hip remplissage from May 2013 to April 2018 were prospectively evaluated. Pre- and postoperative patient-reported outcome scores were compared and included the 12-Item Short Form Survey (SF12) Physical Health Composite Score (PCS), SF12 Mental Health Composite Score (MCS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), modified Harris Hip Score (mHHS), and Hip Outcome Score (HOS) (Activities of Daily Living [ADL] and Sport). Postoperative Tegner Activity Scale and patient satisfaction (1-10) were also evaluated.

RESULTS

Thirteen patients (2 men, 11 women) with an average age of 39.8 ± 9 years underwent arthroscopic hip remplissage with minimum 2-year and mean 3.1-year follow-up (range, 2.1-4.1 years). One hundred percent follow-up was achieved. The average number of previous surgeries was 1.38 (range, 1-3). One patient underwent total hip arthroplasty 2 years after remplissage. All 12 patients who did not undergo total hip arthroplasty had improved patient-reported outcomes after remplissage (mean scores: SF12 PCS 36 vs 42, P = .02; SF12 MCS 45 vs 51, P = .14; mHHS 45 vs 66, P < .001; minimal clinically important difference [MCID] 83%; WOMAC 42 vs 28, P < .001; HOS ADL 52 vs 69, P = .003; MCID, 67%; HOS Sport 27 vs 46, P = .015; MCID, 67%). All improvements met statistical significance, besides the SF12 MCS. Median postoperative Tegner score was 2.9. Median postoperative patient satisfaction was 7 out of 10 (range, 5-10).

CONCLUSIONS

Arthroscopic hip remplissage is a successful salvage treatment option for hip instability caused by previous cam over-resection. Care must be taken during primary surgery not to over-resect the cam as patient-reported outcomes after remplissage are inferior to those undergoing primary hip arthroscopy.

LEVEL OF EVIDENCE

Level IV, case series.

Influence of fixation on CA4+ contrast enhanced microCT of articular cartilage and subsequent feasibility for histological evaluation

CA4+ is a novel cationic iodinated contrast agent utilized for contrast-enhanced microCT (CECT). In this study, we compared CA4+ CECT for cartilage quantification of unfixed and neutral buffered formalin (NBF)-fixed rabbit distal femur cartilage after 8-, 24- and 30-hours of contrast agent diffusion. The stability of CA4+ binding to cartilage after PBS soak and decalcification was also investigated by CECT. We further assessed the feasibility of cartilage histology and immunohistochemistry after CA4+ CECT. Contrast-enhanced CA4+ labeled unfixed and NBF-fixed cartilage tissues facilitate articular cartilage quantification and accurate morphological assessment. The NBF fixed tissues demonstrate higher cartilage intensity and imaging characteristics distinct from subchondral bone than unfixed tissues while maintaining stable binding even after decalcification with 10% EDTA. The unfixed tissues labeled with CA4+, after CECT imaging and decalcification, are amenable to H&E, Alcian blue, and Safranin O staining, as well as Col2 immunohistochemistry. In contrast, only H&E and Alcian blue staining can be accomplished with CA4+ labeled NBF fixed cartilage, and CA4+ labeling interferes with downstream immunohistochemistry and Safranin O staining, likely due to its positive charge. In conclusion, CA4+ CECT of NBF fixed tissues provides high quality microCT cartilage images and allows for convenient quantification along with feasible downstream H&E and Alcian blue staining after decalcification. CA4+ CECT of unfixed tissues enables researchers to obtain both quantitative microCT as well as cartilage histology and immunohistochemistry data from one set of animals in a cost-, time-, and labor-efficient manner.

Comparison of Autologous Blood Clots with Fibrin Sealant as Scaffolds for Promoting Human Muscle-Derived Stem Cell-Mediated Bone Regeneration

Background. Fibrin sealant has been used as a scaffold to deliver genetically modified human muscle-derived stem cells (hMDSCs) for bone regeneration. Alternatively, autologous blood clots are safe, economic scaffolds. This study compared autologous blood clot (BC) with fibrin sealant (FS) as a scaffold to deliver lenti-BMP2/GFP-transduced hMDSCs for bone regeneration. Methods. In vitro osteogenic differentiation was performed using 3D pellet culture and evaluated using microCT and Von Kossa staining. The lenti-GFP transduced cells were then mixed with human blood for evaluation of osteogenic differentiation. Furthermore, a murine critical- sized calvarial defect model was utilized to compare BC and FS scaffolds for lenti-BMP2/GFP-transduced hMDSCs mediated bone regeneration and evaluated with micro-CT and histology. Results. Lenti-BMP2/GFP transduced hMDSCs formed significantly larger mineralized pellets than non-transduced hMDSCs. hMDSCs within the human blood clot migrated out and differentiated into ALP⁺ osteoblasts. In vivo, BC resulted in significantly less new bone formation within a critical-sized calvarial bone defect than FS scaffold, despite no difference observed for GFP⁺ donor cells, osteoclasts, and osteoblasts in the newly formed bone. Conclusions. Human lenti-BMP2/GFP-transduced hMDSCs can efficiently undergo osteogenic differentiation in vitro. Unexpectedly, the newly regenerated bone in BC group was significantly less than the FS group. The autologous blood clot scaffold is less efficacious for delivering stem cells for bone regeneration than fibrin sealant.

The Beneficial Effect of an Intra-articular Injection of Losartan on Microfracture-Mediated Cartilage Repair Is Dose Dependent

BACKGROUND

A previous publication demonstrated that the oral intake of losartan promoted microfracture-mediated hyaline-like cartilage repair in osteochondral defects of a rabbit knee model. However, an intra-articular (IA) injection of losartan may have direct beneficial effects on cartilage repair and has not been studied.

PURPOSE

To determine the dosage and beneficial effects of an IA injection of losartan on microfracture-mediated cartilage repair and normal cartilage homeostasis.

STUDY DESIGN

Controlled laboratory study.

METHODS

Rabbits were divided into 5 groups (n = 6 each): a microfracture group (MFX group) and 4 different losartan treatment groups that received varying doses of IA losartan (0.1, 1, 10, and 100 mg per knee). An osteochondral defect (5 mm) was created in the trochlear groove cartilage of 1 limb in each rabbit, and 5 microfracture perforations were made in the osteochondral defect. Both the injured and the contralateral knee joints were injected with IA losartan immediately after microfracture and at 2 and 4 weeks after surgery. Rabbits were sacrificed at 6 weeks after surgery for analysis including gross observation, micro-computed tomography, histology, and reverse transcription quantitative polymerase chain reaction.

RESULTS

Micro-computed tomography and gross observation demonstrated comparable subchondral bone healing and hyaline-like cartilage morphology in the 0.1-, 1-, and 10-mg losartan groups relative to the MFX group. Conversely, the 100-mg losartan group showed neither bony defect healing nor cartilage repair. Histology revealed higher O'Driscoll scores and hyaline-like cartilage regeneration in the 1-mg losartan group compared with the MFX group. In contrast, the 100-mg losartan group showed the lowest histology score and no cartilage repair. An IA injection of losartan at the doses of 0.1, 1, and 10 mg did not cause adverse effects on uninjured cartilage, while the 100-mg dose induced cartilage damage. Quantitative polymerase chain reaction results showed downregulation of the transforming growth factor β (TGF-β) signaling pathway after IA losartan injection.

CONCLUSION

An IA injection of losartan at the dose of 1 mg was most effective for the enhancement of microfracture-mediated cartilage repair without adversely affecting uninjured cartilage. Conversely, a high dose (100 mg) IA injection of losartan inhibited cartilage repair in the osteochondral defect and was chondrotoxic to normal articular cartilage.

CLINICAL RELEVANCE

An IA injection of losartan at an optimal dosage represents a novel microfracture enhancement therapy and warrants a clinical trial for future clinical applications.

Defining Critical Glenoid Bone Loss in Posterior Shoulder Capsulolabral Repair

BACKGROUND

Although critical bone loss for anterior instability is well defined, a clinically significant threshold of posterior bone loss has not been elucidated.

HYPOTHESIS

Patients with failed arthroscopic posterior shoulder capsulolabral repair will have increased posterior glenoid bone loss with a defined critical threshold.

STUDY DESIGN

Case control study; Level of evidence, 3.

METHODS

Athletes older than 18 years with unidirectional posterior instability treated with arthroscopic repair were evaluated at 2-year minimum follow-up. Failure was defined as revision surgery, American Shoulder and Elbow Surgeons (ASES) score of <60, or subjective stability score of >5. Magnetic resonance imaging (MRI) measurements from 19 patients with failed arthroscopic posterior shoulder capsulolabral repair were compared with 56 patients whose surgery was successful. MRI measures included glenoid version, labral version, glenoid width, labral width, percentage bone loss using the circle technique, labral height, percent subluxation, and recently described measures of defect slope, bone loss angle, and defect length. The P value threshold was set at .05, and a multivariable logistic regression analysis was performed for evaluation of risk of surgical failure.

RESULTS

Smaller glenoid width and greater percentage glenoid bone loss (25.5 ± 0.68 mm vs 28.8 ± 0.47 mm; P < .001; 6.8% ± 0.64% vs 4.6% ± 0.43%; P = .008) were seen in those patients with failed surgery. There was no difference in glenoid version or other measurements between the failures and nonfailures. A cutoff of 11% glenoid bone loss resulted in a 10.4 times statistically higher surgical failure rate, while a 15% bone loss resulted in a 24.4 times statistically higher failure rate. Six patients had >11% bone loss (range, 11.1 to 19.3) and 1 patient had >15% bone loss.

CONCLUSION

Risk factors for failure of arthroscopic posterior shoulder capsulolabral repair include smaller glenoid bone width and greater percentage of glenoid bone loss. A threshold of 11% posterior glenoid bone loss implicated a 10 times higher surgical failure rate, while a threshold of 15% led to a 25 times higher surgical failure rate. Surgical failure of posterior capsulolabral repair, however, is relatively rare as it is an overall successful intervention.

Editorial Commentary: High Level of Evidence Randomized Controlled Trials May Report Statistically Fragile Conclusions

Randomized controlled trials (RCTs) are considered the gold standard for evidence-based medicine, and although a well-designed and executed RCT can be extremely powerful, many RCTs have significant flaws that may significantly impact the strength of their conclusions. The fragility index is a metric that objectifies the strength of results from RCTs and is one such metric that should be considered when critically evaluating individual studies. Although the RCTs pertaining to hip arthroscopy have a median value of 4, which is slightly greater than other orthopaedic subspecialties investigated thus far, this is far from a robust result, which mostly highlights the difficulty in performing an RCT in the surgical realm. Some topics of investigation may be better suited for well performed case-control, matched cohort, and meta-analysis studies (among other investigation types), which may provide better and more robust conclusions than a poorly performed RCT. In essence, don't be enamored by level of evidence alone.

Intra-articular Injection of Bevacizumab Enhances Bone Marrow Stimulation-Mediated Cartilage Repair in a Rabbit Osteochondral Defect Model

BACKGROUND

Bone marrow stimulation (BMS) via microfracture historically has been a first-line treatment for articular cartilage lesions. However, BMS has become less favorable because of resulting fibrocartilage formation. Previous studies have shown that angiogenesis blockade promotes cartilage repair. Bevacizumab is a Food and Drug Administration-approved medication used clinically to prevent angiogenesis.

HYPOTHESIS

The intra-articular injection of bevacizumab would prevent angiogenesis after BMS and lead to improved cartilage repair with more hyaline-like cartilage.

STUDY DESIGN

Controlled laboratory study.

METHODS

The dose of bevacizumab was first optimized in a rabbit osteochondral defect model with BMS. Then, 48 rabbits (n = 8/group/time point) were divided into 3 groups: osteochondral defect (defect), osteochondral defect + BMS (BMS group), and osteochondral defect + BMS + bevacizumab intra-articular injection (bevacizumab group). Rabbits were sacrificed at either 6 or 12 weeks after surgery. Three-dimensional (3D) micro-computed tomography (microCT), macroscope score, modified O'Driscoll histology scores, collagen type 2, Herovici staining, and hematoxylin and eosin staining were performed. Angiogenesis markers were also evaluated.

RESULTS

The intra-articular dose of 12.5 mg/0.5 mL bevacizumab was found to be effective without deleteriously affecting the subchondral bone. Intra-articular injection of bevacizumab resulted in significantly improved cartilage repair for the bevacizumab group compared with the BMS or the defect group based on 3D microCT, the macroscope score (both P < .05), the modified O'Driscoll histology score (P = .0034 and P = .019 vs defect and BMS groups, respectively), collagen type 2, Herovici staining, and hematoxylin and eosin staining at 6 weeks. Cartilage in the bevacizumab group had significantly more hyaline cartilage than did that in other groups. At 12 weeks, the cartilage layer regenerated in all groups; however, the bevacizumab group showed more hyaline-like morphology, as demonstrated by microCT, histology scores (P < .001 and .0225 vs defect and BMS groups, respectively), histology, and immunohistochemistry. The bevacizumab injection did not significantly change mRNA expressions of smooth muscle actin, vascular endothelial growth factor, or hypoxia-inducible factor-1 alpha.

CONCLUSION

Intra-articular injection of bevacizumab significantly enhanced the quality and quantity of hyaline-like cartilage after BMS in a rabbit model. Future large-animal and human studies are necessary to evaluate the clinical effect of this therapy, which may lead to improved BMS outcomes and thus the durability of the regenerated cartilage.

CLINICAL RELEVANCE

The use of bevacizumab may be an important clinical adjunct to improve BMS-mediated cartilage repair.

Segmental Meniscus Allograft Transplantation

Meniscal tears treated with partial meniscectomies have been shown to significantly increase contract pressures within the tibiofemoral joint, and a complete focal meniscal deficiency may render the entirety of the meniscus functionally incompetent. Although various techniques of meniscal transplantation have been described, these techniques may require the excision of a considerable amount of healthy meniscal tissue. Furthermore, failures continue to frequently occur. Therefore, attempts to restoring normal knee kinematics and biomechanical forces are essential. Segmental meniscus allograft transplantations may offer the advantage of a robust repair by both maintaining knee biomechanics and biology while maximizing preservation of native meniscal tissue. Also, most meniscal deficiency involves only a portion of the meniscus, and thus we developed this technique to segmentally transplant only the deficient portion. The purpose of this Technical Note is to describe a technique of segmental medial meniscus allograft transplantation in a patient with focal medial meniscus deficiency.

Full-Thickness Radial Medial Meniscal Tear: Fixation With Inside-Out Technique With Tibial Knotless Suture Anchors

Complete radial tears of the meniscus render the entirety of the meniscus functionally incompetent (known as an ameniscal state); therefore, attempts at repair are essential. Although various techniques have been described, repair failures continue to frequently occur, especially with the medial meniscus. Inside-out repair and anchoring of the preserved meniscus to both the capsule and tibia may offer the advantage of a more robust repair. The objective of this Technical Note is to describe a method of repair for complete radial tears of the medial meniscus using a combination of inside-out sutures and secondary reinforcement to the tibia using all-suture knotless anchors.

Open Popliteal Tendon Repair

Popliteal tendon tears without concomitant damage to the cruciate ligaments or other posterolateral corner ligaments are rare entities with few studies reporting on their existence, with rare case reports discussing their treatment. Continued pain, instability, and effusions are typical symptoms, with magnetic resonance imaging being the main tool for diagnosis. Furthermore, monosodium urate crystals that induce gout have been shown to collect in the popliteal groove and thus may lead to degeneration and isolated tearing. Most case reports have reviewed arthroscopic debridement of the tendon in patients with continued pain. However, in the young athletic population, open repair, if the tissue appears to be of adequate quality, should be a consideration. The use of suture anchors to restore the popliteus to its anatomic footprint is desired. This Technical Note describes a safe and reliable technique for open popliteal tendon repair of an isolated avulsion injury.