Anatomic Shoulder Arthroplasty in Walch C Glenoid Deformity: Mid-to-Long Term Outcomes

BACKGROUND

Hypoplastic glenoid morphology in the setting of glenohumeral osteoarthritis is a rare, yet complex surgical problem. Treatment of this patient population with an anatomic total shoulder arthroplasty (aTSA) remains controversial. Furthermore, there is no gold standard approach with limited guidance for surgeons on the need for glenoid version correction in the setting of a dysplastic glenoid. The purpose of this study was to evaluate mid-to-long term outcomes and reoperation rates of aTSA for treatment of primary glenohumeral osteoarthritis with Walch C glenoid deformity.

METHODS

This observational, retrospective cohort study reviewed patients with a Walch C glenoid undergoing aTSA at two institutions between 2007 and 2016. Patients were contacted to complete updated patient-reported outcome measures at a minimum of 5.5 years postoperatively. Outcome measures collected included the American Shoulder and Elbow Surgeons (ASES) score and Single Alpha Numeric Evaluation (SANE) score. Secondary outcomes included any additional surgery on the operative shoulder, patient satisfaction, and willingness to undergo aTSA again.

RESULTS

Thirty patients met inclusion criteria, and 26 (86.7%) were able to be contacted for final outcomes evaluation. Mean age at time of surgery was 61.3 (range, 40.9 to 75.5) and 20 patients (76.9%) were male. Mean follow-up was 8.5 years (range 5.5 to 11.3) after surgery. Nine patients were treated with an augmented component and 17 with a standard component. Of the 17 non-augmented components, 9 were partially corrected with asymmetric reaming, 3 cases utilized a mini inset glenoid, and 2 cases anteriorly offset the humeral component. At final follow-up, patients had a mean ASES score of 83.6 +/- 16.7, ASES pain score of 24.7 +/- 20.8, SANE score of 80.4 +/- 20.9, and percent patient satisfaction of 84.1%. There were no statistically significant differences in any outcome measure between those with augmented and non-augmented glenoid components. There was one revision to reverse for instability at 7 years postoperatively after a traumatic dislocation. All patients reported that they would want to undergo the same surgery again.

DISCUSSION

Despite variance in glenoid reconstructive approach, aTSA provides satisfactory and sustained improvements in patient-reported outcomes in patients with glenoid dysplasia and primary glenohumeral osteoarthritis with a low revision rate at mean 8.5 years. Anatomic shoulder arthroplasty should remain a surgical option in patients with Walch C glenoid deformity.

Biomechanical Analysis of Posterior Open-Wedge Osteotomy and Glenoid Concavity Reconstruction Using an Implant-Free, J-Shaped Iliac Crest Bone Graft

BACKGROUND

Posterior open-wedge osteotomy and glenoid reconstruction using a J-shaped iliac crest bone graft showed promising clinical results for the treatment of posterior instability with excessive glenoid retroversion and posteroinferior glenoid deficiency.

PURPOSE

To evaluate the biomechanical performance of the posterior J-shaped graft to restore glenoid retroversion and posteroinferior deficiency in a cadaveric shoulder instability model.

STUDY DESIGN

Controlled laboratory study.

METHODS

A posterior glenoid open-wedge osteotomy was performed in 6 fresh-frozen shoulders, allowing the glenoid retroversion to be set at 0°, 10°, and 20°. At each of these 3 preset angles of glenoid retroversion, the following conditions were simulated: (1) intact joint, (2) posterior Bankart lesion, (3) 20% posteroinferior glenoid deficiency, and (4) posterior J-shaped graft (at 0° of retroversion). With the humerus in the Jerk position (60° of glenohumeral anteflexion, 60° of internal rotation), stability was evaluated by measuring posterior humeral head (HH) translation (in mm) and peak translational force (in N) to translate the HH over 25% of the glenoid width. Glenohumeral contact patterns were measured using pressure-sensitive sensors. Fixation of the posterior J-graft was analyzed by recording graft micromovements during 3000 cycles of 5-mm anteroposterior HH translations.

RESULTS

Reconstructing the glenoid with a posterior J-graft to 0° of retroversion significantly increased stability compared with a posterior Bankart lesion and posteroinferior glenoid deficiency in all 3 preset degrees of retroversion (P < .05). There was no significant difference in joint stability comparing the posterior J-graft with an intact joint at 0° of retroversion. The posterior J-graft restored mean contact area and contact pressure comparable with that of the intact condition with 0° of retroversion (222 vs 223 mm², P = .980; and 0.450 vs 0.550 MPa, P = .203). The mean total graft displacement after 3000 cycles of loading was 43 ± 84 µm, and the mean maximal mediolateral graft bending was 508 ± 488 µm.

CONCLUSION

Biomechanical analysis of the posterior J-graft demonstrated reliable restoration of initial glenohumeral joint stability, normalization of contact patterns comparable with that of an intact shoulder joint with neutral retroversion, and secure initial graft fixation in the cadaveric model.

CLINICAL RELEVANCE

This study confirms that the posterior J-graft can restore stability and glenohumeral loading conditions comparable with those of an intact shoulder.

Total shoulder arthroplasty using an inlay glenoid component for glenoid deficiency: mid- to long-term follow-up of a previously published cohort

BACKGROUND

The short-term results of total shoulder arthroplasty with an inlay glenoid component performed by a single surgeon in patients with glenoid bone loss have previously been reported. The purpose of this study was to investigate the mid- to long-term clinical and radiographic outcomes of these patients.

METHODS

We identified a cohort of patients who underwent total shoulder arthroplasty with an inlay glenoid component performed by a single surgeon between 2010 and 2019 for severe glenoid dysplasia and/or glenoid bone loss. Patients with a minimum of 2 years' follow-up were evaluated regarding preoperative and postoperative range of motion, radiographic findings, visual analog scale pain scores, and Single Assessment Numeric Evaluation scores.

RESULTS

Overall, 39 shoulders in 33 patients were treated with an inlay glenoid component for severe glenoid bone loss. Four patients were lost to follow-up, and 1 patient died with a well-functioning implant in place. The final cohort included 34 shoulders in 28 patients (46.4% female patients [13 of 28] and 53.6% male patients [15 of 28]) with a mean age of 66.9 years (range, 58-81 years) and mean follow-up period of 68.3 months. Of the 34 cases, 5 were revision cases. One patient died following 2-year follow-up. Of the shoulders, 10 were classified as Walch type A2, 4 were classified as Walch type B3, and 15 were classified as Walch type C; 5 shoulders were unable to be classified. We observed statistically significant increases in range of motion (forward elevation, 38.1° [P < .001]; external rotation, 18.8° [P < .001]) and improvement in the Single Assessment Numeric Evaluation score (from 26.6 to 81.0, P < .001). Two patients underwent conversion to reverse shoulder arthroplasty at 2.2 and 1.7 years postoperatively.

CONCLUSION

Inlay glenoid components provide a low rate of revision and improved clinical and functional outcomes at mid- to long-term follow-up.

Long-term results after posterior open glenoid wedge osteotomy for posterior shoulder instability associated with excessive glenoid retroversion

BACKGROUND

Treatment of posterior shoulder instability (PSI) associated with excessive glenoid retroversion is a rare, challenging problem in shoulder surgery. One proposed technique is posterior open wedge glenoid osteotomy to correct excessive glenoid retroversion as described by Scott. However, this operation is rarely performed, and limited long-term outcomes using this approach are available. The goal of this study was to analyze the long-term outcomes of posterior open wedge glenoid osteotomy for PSI associated with excessive glenoid retroversion.

METHODS

Six consecutive patients (7 shoulders) with a mean age of 24 years (range 19-34) were treated with posterior open wedge glenoid osteotomy for PSI associated with a glenoid retroversion greater than 15° and followed up clinically and radiographically at a mean age of 15 years (range 10-19).

RESULTS

Recurrent, symptomatic PSI was observed in 6 of 7 shoulders (86%). One necessitated revision with a posterior (iliac crest) bone block procedure and was rated as a failure and excluded from functional analysis. One patient rated his result as excellent, 3 as good, 1 as fair, and 1 as unsatisfactory. Mean relative Constant Score (CS%) was unchanged from preoperation to final follow-up (CS% = 72%) and pain did not significantly decrease (Constant Score = 7-10 points; P = .969). The mean Subjective Shoulder Value (SSV) improved postoperatively, but with 6 patients the improvement did not reach statistical significance (SSV = 42%-67%, P = .053) and the total Western Ontario Shoulder Instability Index averaged 30% at the final follow-up. Mean glenoid retroversion of all 7 shoulders was corrected from 20° (range 16°-26°) to 3° (range -3° to +8°) (P = .018). In the 5 shoulders with preoperative static posterior subluxation of the humeral head, the humeral head was not recentered. All 7 shoulders showed progression of glenoid arthritic changes.

CONCLUSIONS

Posterior open wedge glenoid osteotomy for PSI associated with excessive glenoid retroversion neither reliably restored shoulder stability nor recentered the joint or prevent progression of osteoarthritis. Alternative treatments for PSI associated with excessive glenoid retroversion have to be developed and evaluated.

High incidence of posterior glenoid dysplasia of the shoulder in young baseball players

BACKGROUND

Rounding of the posterior glenoid rim is observed in young throwing athletes with internal shoulder impingement and is considered developmental dysplasia of the glenoid. The aim of our study was to determine the incidence rate of dysplastic changes of the glenoid within a group of 92 young baseball players.

METHODS

The study group included 92 male baseball players, with a mean age of 14.63 years. Of these patients, 30 were diagnosed with Little Leaguer's shoulder and 62 with a painful baseball-throwing shoulder with no abnormal findings on x-ray. The posterior glenoid rim of the affected shoulder was compared with the contralateral nonpainful shoulder, with the 2 following outcomes measured on radiographs obtained using the modified Bernageau imaging method: the distance between the anterior and posterior glenoid rims and the presence or absence of dysplasia of the posterior glenoid rim.

RESULTS

The mean distance between the anterior and posterior glenoid rims was significantly shorter in the painful shoulders (mean, 26 mm) than in the nonpainful shoulders (mean, 29 mm; P < .0001). Dysplasia of the posterior glenoid rim was identified in 89 painful shoulders (96.7%), with 9 cases (9.7%) identified on the unaffected contralateral side (P < .001). The presence of dysplasia was not correlated with the age at which baseball playing began.

CONCLUSION

The incidence of dysplasia of the posterior glenoid rim is high (96.7%) among young baseball players with a painful shoulder. The identified dysplasia may be related to impaired development of the inferior peripheral secondary glenoid ossification center due to repetitive throwing.

Shoulder Arthroplasty for Sequelae of Obstetrical Brachial Plexus Injury

PURPOSE

Shoulder arthroplasty following obstetrical brachial plexus injury (OBPI) is technically challenging because glenoid morphology, muscle balance, and humeral version are substantially altered compared with the neurologically intact shoulder. The purpose of this study is to report the outcome of shoulder arthroplasty in a group of patients with end-stage arthritis secondary to OBPI.

MATERIALS AND METHODS

Seven patients with OBPI and secondary glenohumeral arthritis were treated with shoulder arthroplasty between 1976 and 2014. Two underwent hemiarthroplasty (HA), 2 underwent total shoulder arthroplasty (TSA), and 3 underwent reverse shoulder arthroplasty (RSA). One HA was lost to follow-up and was excluded. The remaining 6 patients (mean age, 62.5 years old at the time of surgery) were followed for a minimum of 2 years (mean, 7.5 years; range, 2-13 years) Outcome measures included pain, range of motion, and postoperative modified Neer ratings.

RESULTS

Pain improved in all shoulders. Mean forward flexion was unchanged. No shoulders treated with HA/TSA regained forward elevation above 90°, compared with 1 out of the 3 RSAs. External rotation improved from a mean of -10° to 20°. Active internal rotation decreased from L1 to L5. Immediate postoperative radiographs showed either severe posterior or posterosuperior subluxation in all 3 patients treated with nonconstrained implants.

CONCLUSIONS

Shoulder arthroplasty is an acceptable option to relieve pain in patients with symptomatic shoulder arthritis as a sequel of OBPI. However, range of motion improvements are not expected.

TYPE OF STUDY /LEVEL OF EVIDENCE

Therapeutic V.

Guidelines for humeral subluxation cutoff values: a comparative study between conventional, reoriented, and three-dimensional computed tomography scans of healthy shoulders

BACKGROUND

The humeral subluxation index (HSI) is frequently assessed on computed tomography (CT) scans in conditions of the shoulder characterized by humeral displacement. An arbitrarily set HSI cutoff value of 45% for anterior subluxation and 55% for posterior subluxation has been widely accepted. We studied whether mean values and thresholds of humeral subluxation, in relation to the glenoid and scapula, were influenced by different imaging modalities.

METHODS

The HSIs referenced to the scapula (SHSI) and glenoid (GHSI) were compared between conventional CT scans, CT scans reoriented into the corresponding reference plane (ie, scapular plane for the SHSI and glenoid center plane for the GHSI), and 3-dimensional (3D) CT reconstructions of 120 healthy shoulders. The 95% normal range determined the cutoff values of humeral subluxation.

RESULTS

The SHSI thresholds for conventional, reoriented, and 3D CT scans were 33%-61%, 44%-68%, and 49%-61%, respectively. A different mean SHSI was found for each imaging modality (conventional, 47%; reoriented, 56%; 3D, 55%; P ≤ .014), with the conventional SHSI showing an underestimation in 89% of the cases. GHSI thresholds for conventional, reoriented, and 3D CT scans were 40%-61%, 44%-56%, and 46%-54%, respectively. The mean GHSI did not differ between each imaging modality (conventional, 51%; reoriented, 50%; 3D, 50%; P = .146).

CONCLUSIONS

The SHSI and GHSI are susceptible to different imaging modalities with consequently different cutoff values. The redefined HSI cutoff values guide physicians in the evaluation of humeral subluxation in conditions characterized by humeral displacement, depending on the available image data.

Arthroscopic treatment of posterior shoulder instability in patients with and without glenoid dysplasia: a comparative outcomes analysis

BACKGROUND

The purpose of this study was to evaluate the influence of glenoid dysplasia on outcomes after isolated arthroscopic posterior labral repair in a young military population.

METHODS

Thirty-seven male patients who underwent arthroscopic posterior labral repair for symptomatic posterior shoulder instability were evaluated at a mean duration of 3.1 years. A comparative analysis was performed for those with glenoid dysplasia and without dysplasia. Additional factors analyzed included military occupational specialty (MOS), preoperative mental health clinical encounters and mental health medication use, and radiographic characteristics (version, posterior humeral head subluxation, and posterior capsular area) on a preoperative standard shoulder magnetic resonance arthrogram. The groups were analyzed with regard to shoulder outcome scores (subjective shoulder value [SSV], American Shoulder and Elbow Surgeons [ASES] rating scale, Western Ontario Shoulder Instability Index [WOSI]), need for revision surgery, and medical separation from the military.

RESULTS

Of 37 patients, 3 (8.1%) underwent revision surgery and 6 (16%) underwent medical separation. Overall outcome assessment demonstrated a mean SSV of 67.9 (range, 25-100) ± 22.1, mean ASES of 65.6 (range, 15-100) ±  22, and mean WOSI of 822.6 (range, 5-1854) ± 538. There were no significant differences in clinical outcome scores between the glenoid dysplasia and no dysplasia groups (SSV, P = .55; ASES, P = .57; WOSI, P = .56). MOS (P = .02) and a history of mental health encounters (P = .04) were significantly associated with diminished outcomes.

CONCLUSIONS

The presence or absence of glenoid dysplasia did not influence the outcome after arthroscopic posterior labral repair in a young military population. However, a history of mental health clinical encounters and an infantry MOS were significantly associated with poorer clinical outcomes.

Critical Findings on Magnetic Resonance Arthrograms in Posterior Shoulder Instability Compared With an Age-Matched Controlled Cohort

BACKGROUND

Posterior shoulder instability is less common and potentially more difficult to diagnose clinically and radiographically compared with anterior shoulder instability. Radiographic findings including posterior labral tears, increased retroversion, presence of glenoid dysplasia, and increased capsular area are associated with symptomatic recurrent posterior shoulder instability.

PURPOSE

This study aimed to determine the prevalence and severity of associated radiographic parameters found on magnetic resonance arthrograms (MRAs) in patients with arthroscopically confirmed isolated posterior labral tears and symptomatic recurrent posterior shoulder instability, compared with an age-matched cohort of patients without posterior instability or labral injury confirmed with shoulder arthroscopy.

STUDY DESIGN

Cross-sectional study, Level of evidence, 3.

METHODS

Patients who received a preoperative standard shoulder MRA at an academic institution over a 5-year period and had symptomatic posterior instability and received a repair of an arthroscopically confirmed posterior labral tear (n = 63) were identified. These patients were compared with an age-matched control group of patients without posterior instability (n = 49) who underwent an isolated arthroscopic distal clavicle resection that included an arthroscopic glenohumeral joint evaluation. Glenoid version, posterior humeral head subluxation, glenoid dysplasia, and linear and capsular area measurements were evaluated between the 2 groups. Interobserver reliability for continuous and categorical variables was assessed for all measurements.

RESULTS

Multivariate logistic regression revealed that the presence of increased glenoid retroversion (P = .0018), glenoid dysplasia (P = .03), and increased axial posterior capsular cross-sectional area (P = .05) were significantly associated with posterior labral tears and symptomatic posterior shoulder instability compared with the age-matched control group. Posterior humeral head subluxation was found to be a statistically significant variable with univariate analysis (P = .001) for posterior shoulder instability but not with multivariate logistic regression (P = .53). Interobserver reliability was good to very good for all measurements (intraclass correlation coefficient [ICC] = 0.74-0.85; κ = 0.64) but was moderate for total capsular area and sagittal capsular area measurements (ICC = 0.43-0.56).

CONCLUSION

The presence of increased glenoid retroversion, glenoid dysplasia, and increased posterior capsular area on MRA are significantly associated with posterior labral tears and symptomatic posterior shoulder instability. Identification of these critical radiographic variables on magnetic resonance arthrography assists in the accurate diagnosis and management of clinically significant posterior shoulder instability.

Total shoulder arthroplasty using an inlay mini-glenoid component for glenoid deficiency: a 2-year follow-up of 9 shoulders in 7 patients

BACKGROUND

Glenoid bone loss and severe retroversion can pose difficulties when implanting a glenoid component for total shoulder arthroplasty for primary osteoarthritis. Mini-glenoid implants may be useful in the setting of severe glenoid wear in which a standard pegged glenoid component cannot be placed.

MATERIALS AND METHODS

This study is a retrospective review, performed over a 3-year period, of patients who received a total shoulder arthroplasty using an inset mini-glenoid in the setting of severe glenoid dysplasia and/or medial glenoid bone loss. We identified patients with a minimum of 2 years' follow-up and evaluated preoperative and postoperative range of motion, visual analog scale scores, Single Assessment Numeric Evaluation scores, complications, and patient satisfaction.

RESULTS

Seven patients (4 female and 3 male patients; 9 shoulders) with a mean age of 66 years were treated with the described procedure and had a mean follow-up of 34 months. There were 6 primary arthroplasties and 3 revision cases. Four shoulders were classified as Walch type A2 glenoids, 2 were classified as Walch type C, and 3 were unable to be classified. There was a statistically significant increase in range of motion (forward elevation, 48°; external rotation, 14°), decrease in pain scores (8 points to 1 point), and improvement in Single Assessment Numeric Evaluation scores (31.7% to 89.4%). The mean patient satisfaction score was 8.6 points on a 10-point scale.

CONCLUSION

At 2-year follow-up, total shoulder arthroplasty with a mini-glenoid component can offer adequate pain relief and functional results in the setting of glenoid bone loss or severe retroversion.

Surgical options for the young patient with glenohumeral arthritis

Young patients with glenohumeral arthritis are an ongoing treatment challenge. They typically have high demands of their shoulders, require long-term durability due to their young age, and often have altered local anatomy, through their disease process (instability arthropathy, juvenile rheumatoid arthritis, etc.) or from previous surgery (capsulorraphy arthropathy, chondrolysis, etc.). Workup to evaluate underlying causes of early arthritis, and to exclude infectious causes are necessary. When nonoperative management fails, arthroscopic debridement, hemiarthroplasty (isolated, with glenoid reaming, or with biological interposition), and total shoulder arthroplasty are treatment options available to the treating surgeon. Debridement or hemiarthroplasty can provide pain relief for a subset of patients, but results have not been reproducible across the literature and have not been durable over time. Total shoulder arthroplasty provides the most reliable pain relief, but long-term glenoid loosening and wear continue to lead to high revision rates in this patient population.