Effect of lesions of the superior portion of the glenoid labrum on glenohumeral translation

Middle trapezius tendon transfer using Achilles allograft for irreparable isolated supraspinatus tendon tears effectively restores the superior stability of the humeral head without restricting range of motion: a biomechanical study

BACKGROUND

Middle trapezius tendon (MTT) transfer has been suggested for promising treatment of irreparable isolated supraspinatus tendon tears (IISTTs). However, there have been no attempts to assess the biomechanical efficacy of MTT transfer. This study aims to evaluate the biomechanical efficacy of MTT transfer in the setting of IISTTs.

METHODS

Eight fresh frozen cadaveric shoulders were tested in 3 conditions: (1) intact rotator cuff, (2) IISTT, and (3) MTT transfer using Achilles allograft for IISTTs. Total humeral rotational range of motion (ROM), superior translation of the humeral head, and subacromial contact characteristics were measured at 0°, 20°, and 40° glenohumeral abduction (representing 0°, 30°, and 60° shoulder abduction). Superior translation and subacromial contact pressures were measured at 0°, 30°, 60°, and 90° external rotation (ER). Two different MTT muscle loading conditions were investigated. A linear mixed effects model and Tukey post hoc test were used for statistical analysis.

RESULTS

Total ROM was significantly increased after IISTT at 20° abduction (P = .037). There were no changes in total ROM following MTT transfer compared to the IISTT condition (P > .625 for all comparisons). The IISTT condition significantly increased superior translation compared to the intact rotator cuff condition in 0° and 20° abduction with all ER angles (P < .001), 40° abduction-30° ER (P = .016), and 40° abduction-60° ER (P = .002). MTT transfer significantly decreased superior translation of the humeral head at all abduction angles compared to the IISTT condition (P < .026). MTT transfer significantly decreased peak contact pressure by 638.7 kPa (normal loading) and 726.8 kPa (double loading) at 0° abduction-30° ER compared to the IISTT condition (P < .001). Mean contact pressure was decreased by 102.8 kPa (normal loading) and 118.0 kPa (double loading) at 0° abduction-30° ER (P < .001) and 101.0 kPa (normal loading) and 99.2 kPa (double loading) at 0° abduction-60° ER (P < .001). MTT transfer at 20° abduction-30° ER with 24 N loading significantly decreased contact pressure by 91.2 kPa (P = .035).

CONCLUSIONS

The MTT transfer biomechanically restored the superior humeral head translation and reduced the subacromial contact pressure in a cadaveric model of IISTT, while not restricting total ROM. These findings suggest that MTT transfer may have potential as a surgical treatment for IISTTs.

3-Tesla T2 Mapping Magnetic Resonance Imaging for Evaluation of SLAP Lesions in Patients with Shoulder Pain: An Arthroscopy-Controlled Study

This study investigated the ability of T2 mapping to assess the glenoid labrum and to differentiate between healthy labral substances and superior labral anterior posterior (SLAP) lesions using arthroscopy as the gold standard. Eighteen patients (mean age: 52.4 ± 14.72 years, 12 men) with shoulder pain were examined using 3-Tesla T2 mapping. All the patients underwent shoulder arthroscopy. Using morphological sequences for correlation, regions of interest covering the entire labral substance were placed in the corresponding T2 maps. The diagnostic cutoff values, sensitivities, and specificities, as well as the inter-reader correlation coefficients (ICCs) determined by two independent radiologists, were calculated. The mean T2 value was 20.8 ± 2.4 ms for the healthy labral substances and 37.7 ± 10.63 ms in the patients with SLAP lesions. The maximum T2 value in normal labrum (21.2 ms) was lower than the minimum T2 value in the patients with SLAP lesions (27.8 ms), leading to sensitivities, specificities, and positive and negative predictive values of 100% (95% CI 54.1-100.0) for all the cutoff values between 21.2 and 27.8 ms. The ICCs ranged from 0.91 to 0.99. In summary, the data suggest that evaluation and quantification of the labral (ultra)structural integrity using T2 mapping may allow discrimination between arthroscopically confirmed SLAP lesions and a healthy glenoid labrum. T2 mapping may therefore be helpful in diagnosing patients with suspected labral damage.

The long head of biceps at the shoulder: a scoping review

BACKGROUND

This review aimed to explore the available literature to update our understanding of the long head of biceps (LHB) at the shoulder. Synthesise our findings to identify emergent themes and knowledge gaps to inform future research and management directions.

METHODS

PubMed, Embase, Cinahl, SportDiscus, CENTRAL, and Web of Science were searched from inception to 31st December 2021. Articles were included if they referenced adult participants > 18 years of age and were written in English.

RESULTS

214 articles were included in the final analysis, and results were categorised into six emergent themes: (1) Anatomy - Normal anatomical variation of the biceps from aberrant origins, third and fourth accessory heads, and an absence of the LHB tendon (LHBT) are not necessarily benign, with shoulder pain and instability a commonly reported theme. (2) Function - Bicep's role in glenohumeral elevation and stability in healthy shoulders is minimal. In contrast, LHB has a more significant role in shoulder stability and humeral head depression in subjects with rotator cuff failure or an absent LHBT. (3) Pathology - There is an association between LHB tendinopathy, rotator cuff disease, LHBT instability and occult rotator cuff tears. Early recruitment and hyperactivity of the LHB in subjects with symptomatic rotator cuff tears and instability suggest a potential compensatory role. (4) Assessment - The limited diagnostic utility of special orthopaedic tests in assessing LHBT pathology was a consistent theme. The utility of magnetic resonance imaging and ultrasound to identify full-thickness tendon tears and instability of the LHBT was moderate to high. However, the utility of clinical tests and imaging may be underestimated due to arthroscopy's limitations in fully visualising the proximal LHBT. (5) Non-Surgical Management - Ultrasound-guided injections into the biceps sheath show greater accuracy and patient outcomes than blinded injections; however, the entry of injectate into the intraarticular glenohumeral joint may have unwanted complications. (6) Surgical management - For the surgical management of biceps pathology with or without rotator cuff pathology, both biceps tenodesis and tenotomy report similar improvements in pain without any significant adverse effect on strength or function. Tenodesis favoured higher overall constant scores and a lower incidence of Popeye deformity and cramping arm pain, with tenotomy trending to be more cost and time effective. For patients with a healthy LHBT, rotator cuff repair with adjunctive tenodesis or tenotomy fails to provide additional clinical improvements compared to rotator cuff repair in isolation.

CONCLUSIONS

The scoping review highlights the variability of biceps anatomy, which is not necessarily benign and suggests a minimal role of the LHB in shoulder elevation and stability in healthy individuals. In contrast, individuals with rotator cuff tears experience proximal humeral migration and demonstrate hyperactivity of the LHB, suggesting a potential compensation role. The observed prevalence of LHBT pathology with rotator cuff tears is well established; however, the cause-and-effect relationship between LHBT pathology and rotator cuff disease is undetermined. The diagnostic utility of clinical tests and imaging to exclude LHBT pathology may be understated due to the limitations of arthroscopy to visualise the proximal LHBT fully. Rehabilitation programs for the LHB are understudied. Similar post-surgical clinical outcomes are observed for tenodesis and tenotomy for biceps and rotator cuff-related shoulder pain. Subjects undergoing biceps tenodesis are less likely to have cramping arm pain and a Popeye deformity than patients undergoing biceps tenotomy. The significance of routine surgical removal of the LHBT and sequelae on rotator cuff tear progression to failure and long-term shoulder function is unknown, and further research is required.

PRE-REGISTRATION

OSF: https://osf.io/erh9m.

A stabilizing role of the glenoid labrum: the suction cup effect

BACKGROUND

The glenoid labrum acts as a bumper, deepening glenoid concavity and amplifying the concavity-compression mechanism, and serves as the scapular attachment for glenohumeral ligaments. The role of the posterosuperior labrum in anteroinferior glenohumeral stability, and the role of the anterior labrum in posterior stability has been debated. The purpose of this study was to quantify the contribution of anteroinferior and posterosuperior labral tears to loss of glenohumeral stability in multiple directions.

METHODS

Fourteen fresh-frozen cadaveric shoulders were tested on a custom stability ratio measurement apparatus. The peak force that was required to translate the humeral head in anterior, anteroinferior, posterior, and posteroinferior directions was measured under 5 conditions: intact labrum (n = 14), anteroinferior labral tear (n = 7), posterosuperior labral tear (n = 7), combined labral tear (n = 14), and no labrum (n = 14). The stability ratio was defined as the peak translational force divided by the compressive force. Within force-translation curves, we defined the suction cup effect as the force required to release the negative pressure created by an intact labrum.

RESULTS

The suction cup effect was usually present with the intact labrum and always disappeared after removal of the labrum for anterior (100% vs. 0%) and posterior (86% vs. 0%) translations (P < .001). After creation of an anteroinferior labral tear, the stability ratio for posterior direction decreased (P < .001) and the suction cup effect disappeared (P < .001). After creation of a posterosuperior labral tear, stability ratios in the anterior and anteroinferior directions decreased (P ≤ .006) and the suction cup effect disappeared (P ≤ .015). The stability ratio for anterior and anteroinferior testing was more diminished by posterosuperior labral tears than anteroinferior labral tears, and the stability ratio for posterior testing was more diminished by anteroinferior labral tears than posterosuperior labral tears.

CONCLUSION

Anteroinferior labral tears decreased posterior stability and posterosuperior labral tears decreased anterior and anteroinferior stability, largely because of loss of the suction cup effect.

Biceps Tenodesis Combined With Arthroscopic Posterior Labral Repair for Type VIII SLAP Lesions in Active-Duty Military Patients Yields Excellent Return to Military Duty

PURPOSE

To report short-term outcomes following biceps tenodesis combined with arthroscopic posterior labral repair of type VIII SLAP lesions in active-duty military patients.

METHODS

All consecutive patients from January 2012 through December 2018 who underwent biceps tenodesis combined with arthroscopic posterior labral repair of type VIII SLAP tears performed by the senior surgeon with complete outcome scores and minimum 2.5 years follow-up were identified. Exclusion criteria included concomitant glenoid microfracture, rotator cuff repair, or other capsulolabral repair. Outcome measures were completed by patients within 7 days before surgery and at latest follow-up. Biceps tenodesis performed was a mini-open, through a subpectoral approach, using a double-loaded 2.9mm suture-anchor.

RESULTS

Thirty-two patients met the inclusion criteria for the study. All patients were active-duty military at time of surgery. Average follow-up was 73.53 ± 22.37 months. Thirty-one patients achieved the minimal clinically important difference, 30 of 32 reached the substantial clinical benefit, and 31 of 32 met the patient acceptable symptomatic state, as defined for the American Shoulder and Elbow Surgeons Shoulder Score. Similarly, 30 of 32 patients reached the minimal clinically important difference, 29 of 32 achieved the substantial clinical benefit, and 32 of 32 met the patient acceptable symptomatic state for the Single Assessment Numeric Evaluation. There were no significant changes in forward flexion, external rotation, or internal rotation between pre- and postoperative measurements. Three patients reported postoperative complications and 1 patient progressed to further surgery. Thirty (93.75%) patients remained on active-duty military service and were able to return to preinjury levels of activity.

CONCLUSIONS

Active-duty military patients with type VIII SLAP tears had statistically and clinically significant increases in outcome scores, marked improvement in pain, and high rates of return to unrestricted active-duty following mini-open subpectoral biceps tenodesis combined with posterior labral repair.

LEVEL OF EVIDENCE

IV, retrospective case series.

Outcomes of arthroscopic-assisted middle trapezius tendon transfer for isolated irreparable supraspinatus tendon tears: minimum 2-year follow-up

INTRODUCTION

Middle trapezius tendon (MTT) transfer has been proposed as a feasible option for managing isolated irreparable supraspinatus tears (IISTTs). However, no clinical study has been attempted. This study aimed to evaluate clinical and radiologic outcomes of arthroscopic-assisted MTT transfer in patients with IISTTs.

METHODS

This retrospective study included patients who underwent arthroscopic-assisted MTT transfer using fascia lata autograft for IISTTs. Clinical outcomes, including pain visual analog scale (VAS), Constant, American Shoulder and Elbow Society (ASES), University of California Los Angeles (UCLA) shoulder scores and active range of motion (aROM), were assessed. Radiographic analyses included the acromiohumeral distance (AHD), Hamada grade, and transferred tendon integrity at the final follow-up.

RESULTS

Twenty-two patients (mean age: 63.3 ± 6.8 [51‒74] years; mean follow-up period: 28.9 ± 4.9 [24‒44] months) met the study criteria. The mean VAS, Constant, ASES, and UCLA scores improved postoperatively at the final follow-up (p < 0.001). The mean aROMs for forward flexion and abduction were significantly increased postoperatively. No significant changes of AHD (p = 0.105) and Hamada grade (p = 0.815) were observed postoperatively. One patient had a re-tear of the transferred tendon at the footprint site at the final follow-up.

CONCLUSION

In this minimum 2-year follow-up study of the novel aMTT transfer using fascia lata autograft, we found significant improvement in pain relief, clinical scores, and active forward flexion and abduction. Additionally, no significant progression of cuff tear arthropathy was observed at the final follow-up. Therefore, aMTT transfer could be a promising treatment option for patients with IISTTs. However, further multicenter and long-term trials are needed to verify its effectiveness.

LEVEL OF EVIDENCE

Retrospective case series, level IV.

Anterior glenohumeral capsular ligament reconstruction with hamstring autograft for internal impingement with anterior instability of the shoulder in baseball players: preliminary surgical outcomes

BACKGROUND

Shoulder pain and dysfunction are common in baseball players, and although "internal impingement" is recognized as one of the most common pathologies of shoulder dysfunction, the optimal surgical treatment for internal impingement with anterior instability of the shoulder remains controversial. This study evaluated baseball players' preliminary outcomes following anterior glenohumeral capsular ligament reconstruction for internal impingement with anterior instability of the shoulder.

METHODS

Twelve baseball players (all male; mean age, 20.5 ± 2.2 years) with internal impingement and anterior instability managed via anterior glenohumeral capsular ligament reconstruction were examined. The mean follow-up period was 25.3 ± 4.6 months. Anterior glenohumeral capsular ligament reconstruction was performed with a knee hamstring autograft for balanced stability and laxity with two major targets: to prevent hyperangulation and translation in horizontal abduction and to mimic the individual arm cocking position at the final decision of tension. Preoperative and final follow-up evaluations were performed using Jobe's postoperative grading system; the Kerlan-Jobe Orthopaedic Clinic Overhead Athletes Shoulder and Elbow Score; Disabilities of the Arm, Shoulder and Hand sports module; plain radiographs; and magnetic resonance imaging.

RESULTS

Jobe's postoperative grading system score, the Kerlan-Jobe Orthopaedic Clinic Overhead Athletes Shoulder and Elbow Score, and the Disabilities of the Arm, Shoulder and Hand sports module score improved significantly from 20.4 ± 12.2, 28.4 ± 8.3, and 80.2 ± 11.1 points preoperatively to 88.8 ± 13.6, 80.8 ± 7.7, and 22.4 ± 18.7 points postoperatively, respectively (P < .001, .0025, <0.001, respectively). Both clinical and imaging evaluations revealed improved internal impingement with anterior instability after anterior glenohumeral capsular ligament reconstruction. The mean external rotation at abduction significantly decreased from 113° preoperatively to 104° postoperatively. At follow-up, 10 of the 12 athletes (83.3%) returned to their prior competitive level. Plain radiographs and magnetic resonance imaging revealed no obvious loosening of the graft or screws.

CONCLUSIONS

Anterior glenohumeral capsular ligament reconstruction resulted in preferable clinical outcomes for young baseball players who experienced pain during the throwing motion. Stabilization of the glenohumeral joint with autografting of the knee hamstring may thus represent a solution for internal impingement with anterior instability in overhead throwing athletes.

The role of the long head of the biceps tendon in posterior shoulder stabilization during forward flexion

BACKGROUND

The role of the long head of the biceps tendon (LHBT) in glenohumeral stability is not fully understood. Most objects are lifted in the sagittal plane with forward flexion, which stresses the posterior aspect of the unconstrained glenohumeral joint. Determining the mechanism by which the shoulder maintains stability with functional motions is important to understanding the pathoanatomy of degenerative shoulders. Our hypothesis was that the LHBT resists posterior translation of the humeral head (HH) during forward flexion by tensioning the posterior capsuloligamentous complex.

METHODS

Ten fresh-frozen cadaveric shoulders were tested using an established shoulder simulator that loads the LHBT, rotator cuff, and deltoid tendons through a system of pulleys. A motion tracking system recorded glenohumeral translations with an accuracy of ±0.2 mm. In each subject, the scapula was fixed and the humerus was tested in 6 positions: 30° and 60° of glenohumeral forward flexion at (1) maximum internal rotation (IR), (2) neutral rotation, and (3) maximum external rotation (ER). The deltoid was loaded with 100 N, and the infraspinatus and subscapularis were loaded with 22 N each. The difference in glenohumeral translation was calculated at each position comparing the LHBT loaded with 45 N or unloaded.

RESULTS

At 30° of glenohumeral forward flexion, unloading the LHBT increased HH posterior translation by 2.5 mm (±0.9 mm; P < .001), 1.7 mm (±1.0 mm; P < .001), and 1.0 mm (±0.9 mm; P = .01) at maximum ER, neutral rotation, and maximum IR, respectively. At 60° of glenohumeral forward flexion, unloading the LHBT increased HH posterior translation by 2.8 mm (±1.2 mm; P < .001), 2.4 mm (±1.6 mm; P < .001), and 1.7 mm (±1.4 mm; P < .001) at maximum ER, neutral rotation, and maximum IR, respectively.

CONCLUSION

LHBT loading resists posterior translation of the HH during forward flexion. These data support the role of the LHBT as a posterior stabilizer of the shoulder, specifically when a person is carrying objects in front of them. Further work is needed to determine if unloading the LHBT, as is done with biceps tenotomy or tenodesis, may eventually lead to posterior labral pathology, or to the posterior glenoid wear commonly seen with osteoarthritis.

Disabled Throwing Shoulder 2021 Update: Part 1-Anatomy and Mechanics

The purpose of this article is to provide updated information for sports health care specialists regarding the Disabled Throwing Shoulder (DTS). A panel of experts, recognized for their experience and expertise in this field, was assembled to address and provide updated information on several topics that have been identified as key areas in creating the DTS spectrum. Each panel member submitted a concise presentation on one of the topics within these areas, each of which were then edited and sent back to the group for their comments and consensus agreement in each area. Part 1 presents the following consensus conclusions and summary findings regarding anatomy and mechanics, including: 1) The current understanding of the DTS identifies internal impingement, resulting from a combination of causative factors, as the final common pathway for the great majority of the labral pathoanatomy; 2) intact labral anatomy is pivotal for glenohumeral stability, but its structure does not control or adapt well to shear or translational loads; 3) the biceps plays an active role in dynamic glenohumeral stability by potentiating "concavity compression" of the glenohumeral joint; 4) the ultimate function of the kinetic chain is to optimize the launch window, the precise biomechanical time, and position for ball release to most effectively allow the ball to be thrown with maximum speed and accuracy, and kinetic chain function is most efficient when stride length is optimized; 5) overhead throwing athletes demonstrate adaptive bony, capsular, and muscular changes in the shoulder with repetitive throwing, and precise measurement of shoulder range of motion in internal rotation, external rotation, and external rotation with forearm pronation is essential to identify harmful and/or progressive deficits. LEVEL OF EVIDENCE: Level V, expert opinion.

[Research progress on the relationship between shoulder instability and superior labrum anterior posterior lesion]

OBJECTIVE

To summarize the relationship between shoulder instability and superior labrum anterior posterior (SLAP) lesion.

METHODS

The characteristics of shoulder instability and SLAP lesion were analyzed, and the relationship between them in pathogenesis, clinical symptoms, and biomechanics was discussed by referring to relevant domestic and foreign literature.

RESULTS

Shoulder instability and SLAP lesion can occur both spontaneously and respectively. SLAP lesion destroys the superior labrum integrity and the long head of biceps tendon (LHBT) insertion, causing excessive humeral head displacement against glenoid, and leading to shoulder instability. While chronic repetitive or acute high-energy traumatic shoulder instability can in turn aggravate SLAP lesion, resulting in expansion and increased degree of the original lesion.

CONCLUSION

SLAP lesion destroys mechanisms of shoulder stability, while shoulder instability causes tears of the upper labrum and the LHBT, showing a connection between shoulder instability and SLAP lesion. However, the existing evidence can only demonstrate that shoulder instability and SLAP lesion induce and promote the development of each other, instead of a necessary and sufficient condition. Therefore, the specific causal relationship between the two remains unknown and needs to be further studied.

The Buford complex: prevalence and relationship with labral pathologies

BACKGROUND

This study aimed to determine the prevalence of the Buford complex and to investigate its association with labral pathologies (superior labrum anterior-posterior [SLAP] lesion and anterior, posterior, or multidirectional instability) using a very large patient database. Furthermore, the prevalence of the Buford complex in patients without any labral pathology was also determined.

METHODS

A total of 3129 consecutive shoulder arthroscopy procedures were retrospectively evaluated for the presence of the Buford complex and coexisting labral pathologies. The relationships between the Buford complex and SLAP lesions, as well as instability, were evaluated statistically.

RESULTS

The Buford complex was observed in 83 shoulders (2.65%). SLAP lesions were significantly more frequent in patients with the Buford complex than in those without it (81.9% vs. 33.1%, P < .001) Shoulders with the Buford complex presented a lower frequency of anterior instability (10.8% vs. 19.3%, P = .052) and a higher frequency of posterior instability (1.2% vs. 0.9%, P = .789). The prevalence of the Buford complex in patients with and without labral pathologies was 4.6% and 0.3%, respectively (P < .001).

CONCLUSIONS

This study, to our knowledge, includes the largest cohort in the literature reporting the prevalence of the Buford complex (2.65%). In the 1461 patients without labral tears or multidirectional instability, the prevalence of the Buford complex was 0.3%. This result suggests that the real prevalence of the Buford complex might be lower than that reported previously. In addition to the aforementioned conclusions, the identification of the Buford complex should prompt a thorough evaluation for concomitant SLAP lesions.

Cost Comparison of Open and Arthroscopic Treatment Options for SLAP Tears

Purpose

To identify cost drivers of open biceps tenodesis, arthroscopic biceps tenodesis, and arthroscopic SLAP repair in the setting of isolated SLAP tears and to perform a direct cost comparison between the procedures.

Methods

The 2014 State Ambulatory Surgery and Services Databases from 6 US states were used. Cases with Current Procedural Terminology codes 23430 (tenodesis of long tendon of biceps), 29807 (shoulder arthroscopy, repair of SLAP lesion), and 29828 (shoulder arthroscopy, biceps tenodesis) were selected, excluding patients who were >50 years old or had a concomitant rotator cuff repair. Generalized linear models were used to model costs based on surgical and patient variables.

Results

The mean patient age was 41.8 years for open biceps tenodesis, 31.6 for arthroscopic SLAP repair, and 41.3 for arthroscopic biceps tenodesis (P < .001). Open biceps tenodesis had cost reductions of $5,664 over arthroscopic biceps tenodesis (P = .001) and $2,320 over arthroscopic SLAP repair (P = .043). Male sex was associated with $3,798 more in costs (P < .001), presence of ≥1 comorbidities added $1,829 (P = .002), and each minute in the operating room added $37 (P < .001). Operative time for open biceps tenodesis averaged 114 minutes, and both arthroscopic procedures averaged 94 minutes (P < .001). Low-volume facilities were associated with $5,536 higher costs for arthroscopic biceps tenodesis (P = .001).

Conclusion

In patients aged ≤50 years with isolated SLAP tears, open biceps tenodesis provides cost savings over arthroscopic methods of treatment. There was no significant cost difference between arthroscopic SLAP repairs and arthroscopic biceps tenodesis. Given the increased emphasis on cost containment, surgeons should be aware of the procedural costs associated with the treatment of SLAP tears.

Level of Evidence

III, retrospective cohort study.

The Fifty Most-Cited Articles Regarding SLAP Lesions

Purpose

To identify and evaluate the top 50 most-cited articles pertaining to SLAP tears.

Methods

The ISI Web of Knowledge database was used to conduct a query for articles pertaining to SLAP tears. Our query was conducted in April 2020 with multiple Boolean operative combinations performed by 2 independent reviewers. Articles on the final list were further reviewed to extract the following data: manuscript title, first author, total citation count, year of publication, citation density since publication, current citation rate since 2013, journal, country of origin, and level of evidence.

Results

Our initial search yielded 2,597 articles. Within this cohort, the top 50 publications pertaining to SLAP tears were identified that met our search criteria. The top article was cited 802 times while the 50th ranked article was cited 46 times. The average number of citations per publication was 131, whereas the average citation density since year of publication was 7.3. No strong correlations were found between citation density and year published. Twelve journals published articles pertaining to SLAP tears, with Arthroscopy accounting for the greatest number (15 articles, 30%). Most articles were graded with a level of evidence (LOE) of IV (n = 24, 48%), followed by review articles without LOE (n = 8, 16%). Only 2 articles achieved an LOE of I (4%). Articles typically addressed the arthroscopic management (n = 11, 22%), whereas anatomy/classification (n =10, 20%), and outcomes (n = 9, 18%) also were reported.

Conclusions

This review provides a quantitative analysis of the most-referenced literature pertaining to SLAP tears. This body of knowledge helps surgeons search for literature regarding these injuries and identify trends regarding SLAP tear research.

Clinical Relevance

This research provides practitioners with an easily accessible and comprehensive collection of the major contributions regarding SLAP tears and offers insight into future areas for research.

Shoulder biomechanics in normal and selected pathological conditions

The stability of the glenohumeral joint depends on soft tissue stabilizers, bone morphology and dynamic stabilizers such as the rotator cuff and long head of the biceps tendon. Shoulder stabilization techniques include anatomic procedures such as repair of the labrum or restoration of bone loss, but also non-anatomic options such as remplissage or tendon transfers.

Rotator cuff repair should restore the cuff anatomy, reattach the rotator cable and respect the coracoacromial arch whenever possible. Tendon transfer, superior capsular reconstruction or balloon implantation have been proposed for irreparable lesions.

Shoulder rehabilitation should focus on restoring balanced glenohumeral and scapular force couples in order to avoid an upward migration of the humeral head and secondary cuff impingement. The primary goal of cuff repair is to be as anatomic as possible and to create a biomechanically favourable environment for tendon healing.

Cite this article: EFORT Open Rev 2020;5:508-518. DOI: 10.1302/2058-5241.5.200006

Comparison between SLAP Repair and Biceps Tenodesis with Concomitant Rotator Cuff Repair in Patients Older than 45 Years: Minimum 2-Year Clinical and Imaging Outcomes

Backgroud

There is controversy over how to surgically treat symptomatic superior labrum anterior to posterior (SLAP) tears in middle-aged patients with concomitant rotator cuff tears. The aim of the study was to compare the clinical and imaging outcomes of SLAP repair versus biceps tenodesis (BT) each combined with arthroscopic rotator cuff repair (ARCR).

Methods

We retrospectively reviewed 35 patients older than 45 years who underwent arthroscopic surgery to manage concomitant SLAP tears and rotator cuff tears. In addition to ARCR, 17 patients underwent SLAP repair, whereas 18 patients underwent BT. Shoulder range of motion (ROM), visual analog scale (VAS) for pain, American Shoulder and Elbow Surgeons (ASES) score, Constant score, and University of California at Los Angeles (UCLA) score were used for clinical assessment. The integrity of rotator cuff repair and change of superior labrum-biceps complex were evaluated by postoperative magnetic resonance imaging (MRI).

Results

There was significant improvement in the pain VAS and all functional scores in both groups (p < 0.001) at a mean followup of 29.4 ± 11.4 months (range, 24–84 months) postoperatively. Shoulder ROM showed significant improvement postoperatively (p < 0.05). No significant difference in outcomes could be found between the 2 groups after surgery. The retear rate of rotator cuff repair on MRI was 11.8% in the SLAP repair group and 11.1% in the BT group.

Conclusions

In middle-aged patients with combined SLAP lesions and rotator cuff tears, both SLAP repair and BT can be safe adjuncts to ARCR.

Comparison of the clinical results of isolated Bankart and SLAP 5 lesions after arthroscopic repair

OBJECTIVES

This study aims to compare the clinical results of patients with traumatic isolated Bankart lesions and type V superior labrum anterior to posterior (SLAP) lesions after arthroscopic repair.

PATIENTS AND METHODS

Patients who underwent arthroscopic repair for traumatic anterior glenohumeral instability were evaluated retrospectively between December 2014 and January 2019. Fifty-one patients (49 males, 2 females; mean age 25 years; range, 18 to 36 years) without bone defects affecting >20% of the glenoid fossa, off-track engaging Hills-Sachs lesions, multidirectional instability, or ligamentous laxity were included in the study. Group 1 had 31 patients with isolated Bankart lesions and group 2 had 20 patients with type V SLAP lesions. There were only two female patients in group 1 and all patients were male in group 2. The mean age was 25 years (range, 18 to 36 years) in group 1 and 25 years (range, 19 to 35 years) in group 2. Rowe, Constant, and Western Ontario Shoulder Instability (WOSI) scoring systems were used to evaluate the clinical outcomes of the patients preoperatively and at the last follow-up.

RESULTS

The mean follow-up time was 32 months (range, 12 to 48 months) in group 1 and 28.5 months (range, 12 to 42 months) in group 2. There were no statistically significant differences between the two groups in terms of the number of shoulder dislocations before the surgery, mean age at the time of surgery, and the mean time from the first dislocation to surgical treatment. When the Rowe, Constant, and WOSI scores were evaluated preoperatively and at the last follow-up, there were statistically significant changes within, but not between, the two groups.

CONCLUSION

In type V SLAP lesions, the affected and repaired labrum surface area is larger than isolated Bankart lesions. However, as a result of appropriate surgical treatment, the affected surface area does not have a negative effect on clinical outcomes, and similar clinical results can be obtained in patients with type V SLAP lesions compared to patients with isolated Bankart lesions.

The Effects of Treatment of Korean Medicine for Superior Labrum Anterior to Posterior Lesions: A Retrospective Chart Review

Background: This study aimed to investigate the clinical effectiveness of treatment of Korean medicine on superior labrum anterior to posterior (SLAP) lesions.Methods: A total of 55 inpatients diagnosed with SLAP lesions by magnetic resonance imaging, were investigated from May 1^st, 2014 to May 31^st, 2019 at Haeundae Jaseng Hospital of Korean Medicine. The patients were sorted by gender, age, causing factor, illness duration, period of hospitalization, SLAP lesion type, complications, and treatments. Treatments included acupuncture, pharmacopuncture, Chuna therapy, herbal treatment, and physiotherapy. After treatment, the Numeric Rating Scale, Shoulder Pain and Disability Index, and European Quality of Life 5-Dimension questionnaire were used to evaluate treatment effect.Results: There were more males than females in this study (1:0.83). Patients were more likely to be in their 50s (38.18%), have an unknown etiology (70.91%), and be in the subacute disease stage (41.82%). According to the SLAP lesion type, most of the inpatients had Type 2 lesions (69.09%). For inpatients diagnosed with SLAP lesions, the mean shoulder numeric rating scale score decreased from 5.55 ± 0.90, to 4.07 ± 1.18 (p < 0.001), the mean Shoulder Pain and Disability Index score decreased from 50.35 ± 18.36, to 39.90 ± 19.34 (p < 0.001), and the mean European quality of life 5-dimension index increased from 0.70 ± 0.16, to 0.75 ± 0.13 (p < 0.01) after treatment.Conclusion: Treatment of Korean medicine effectively decreased pain and increased the quality of life of the patients with SLAP lesions in this study.

Arthroscopic Repair of 270- and 360-Degree Glenoid Labrum Tears: A Systematic Review

PURPOSE

To review the current literature available and evaluate the efficacy of arthroscopic repair of 270° and 360° labral tears, as well as the complication rates associated with such. In addition, we intend to investigate whether consistent clinical findings can be observed in these patients.

METHODS

This review is registered in the PROSPERO database. The MEDLINE, Cochrane Library, Scopus, and EMBASE databases were queried, and additional searches were performed manually. Studies that reported outcomes after arthroscopic repair of a minimum of 270° of glenoid labrum were included. Technique articles, repairs of less than 270°, studies on atraumatic multidirectional instability, and studies that lacked observable outcomes were excluded.

RESULTS

In total, 3031 studies/documents were identified from database and manual searching. Screening, removal of duplicates, and assessment for inclusion/exclusion criteria resulted in 6 level IV studies for review. History and physical examination, as well as advanced imaging findings, were variable across studies. All studies reported satisfactory outcomes at short- to mid-term follow-up, although there was heterogeneity in type of outcomes used. Return to sport ranged from 75% to 100%. Complication rates ranged from 10% to 30%. Notably, recurrence of instability and need for secondary surgery occurred in up to 15% of patients.

CONCLUSIONS

The current literature suggests that although clinical and radiographic variability exist in the diagnosis of 270° and 360° glenoid labrum tears, successful outcomes and return to work/sport can be achieved with arthroscopic management at an average minimum follow-up of 1 year. These figures, however, are limited by heterogenous studies containing small numbers of patients. Complications occur in up to 30% of cases, including an instability recurrence rate of up to 15%.

LEVEL OF EVIDENCE

Systematic review of Level IV evidence.

Outcomes for Arthroscopic Repair of Combined Bankart/SLAP Lesions in the Treatment of Anterior Shoulder Instability: A Systematic Review and Meta-analysis

Background

Arthroscopic repair of combined Bankart/superior labral anteroposterior (SLAP) lesions is commonly performed to treat anterior shoulder instability, the clinical outcomes of which have not been widely studied.

Purpose

To compare the clinical outcomes for arthroscopic repair of combined Bankart/SLAP lesions in the treatment of anterior shoulder instability and to ascertain whether it is inferior to isolated Bankart repair.

Study Design

Systematic review; Level of evidence, 3.

Methods

A systematic review of the literature was performed through use of the MEDLINE, EMBASE, and Cochrane Library databases according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Study bias was assessed using the MINORS (Methodological Index for Non-Randomized Studies) scoring system. Randomized controlled trials, prospective or retrospective cohort studies, and case-control studies were included, whereas systematic reviews, literature reviews, conference abstracts, case reports, case series, and non-peer-reviewed studies were excluded to guarantee the quality of the study. Data on outcomes including recurrence rate, functional scores, and range of motion (ROM) were pooled, with statistical analysis performed. A P value of <.05 was considered statistically significant.

Results

The review included 7 studies with a total of 520 patients. The pooled recurrence rate after combined Bankart/SLAP repair was 6.47% (9/139). Significant improvements of postoperative versus preoperative functional scores were observed, including a reduction in the visual analog scale score for pain (mean ± SD: 0.99 ± 1.36 vs 4.13 ± 2.26; P < .00001) and an increase in mean Rowe score (89.56 ± 11.46 vs 43.16 ± 8.87; P < .00001) and mean Constant score (91.41 ± 7.57 vs 59.70 ± 5.63; P < .00001). In terms of ROM, no reduction was found in external rotation (66.56° ± 13.33° vs 67.22° ± 14.27°; P = .21), and a significant increase in abduction was found (157.67° ± 4.11° vs 144.18° ± 8.28°; P < .00001). No statistically significant difference was found between arthroscopic repair of combined Bankart/SLAP lesions and isolated Bankart repair regarding recurrence rate, functional scores, or ROM.

Conclusion

Of the pooled data, patients who underwent arthroscopic repair of combined Bankart/SLAP lesions in treatment of anterior shoulder instability showed a low recurrence rate, favorable functional scores, and no significant restriction on ROM, all of which were not significantly worse than outcomes of isolated Bankart repair. Therefore, combined repair was proven to be a viable option for extensive labral lesions.

Comparative study on clinical results of arthroscopic repair of anteroinferior, superior, and combined glenoid labral tear

BACKGROUND

The purpose of this prospective study is to compare and correlate the clinical results of arthroscopic repair of a combined anteroinferior and superior labral lesion with those of an isolated anteroinferior labral lesion or type II superior labral tear from anterior to posterior (SLAP) lesion.

METHODS

A comparative study involving patients who underwent arthroscopic labral repairs in a tertiary hospital between 2010 and 2014 was conducted. A total of 96 patients were divided into three groups: Group A consisted of 61 patients with the anteroinferior labral lesion, group B consisted of 16 patients with the type II SLAP lesion, and group C consisted of 19 patients with the combined anteroinferior and superior labral lesion. Patient demographics, preoperative and postoperative pain scores, shoulder functional scores (Constant Shoulder Score, UCLA (University of California at Los Angeles) Shoulder Score, and Oxford Instability Score), and shoulder ranges of motion were measured and compared.

RESULTS

Except that patients from group B were generally older (28.8 vs. 22.2 for group A and 22.0 for group C, p = 0.04) at the time of surgery, no significant differences exist among the three groups in patient demographics and relevant clinical data. Preoperative and 2-year postoperative clinical outcomes, as well as the improvements, were comparable among the three groups. Low failure rates were observed for all three groups (6% vs. 10% vs. 11%, p = 0.999).

CONCLUSIONS

Patients with the type II SLAP lesion underwent surgery at an older age. With appropriate surgical procedures, equivalent postoperative results can be expected for combined anteroinferior and superior labral lesion repair compared to isolated labral lesion repair.

Functional and Surgical Anatomy of the Upper Limb: What the Radiologist Needs to Know

The anatomy of the upper limb is complex and allows for exceptional functionality. The movements of the joints of the shoulder, elbow, and wrist represent a complex dynamic interaction of muscles, ligaments, and bony articulations. A solid understanding and of the characteristics and reciprocal actions of the anatomic elements of the joints of the upper limb helps explain the mechanisms and patterns of injury. This article focuses on the anatomy and functionality of the shoulder, elbow, and wrist, with emphasis on the stabilizing mechanisms, to set the foundation for understanding the occurrence of pathologic conditions.

Is arthroscopic repair superior to biceps tenotomy and tenodesis for type II SLAP lesions? A meta-analysis of RCTs and observational studies

Objective

Labral repair and biceps tenotomy and tenodesis are routine operations for type II superior labrum anterior posterior (SLAP) lesion of the shoulder, but evidence of their superiority is lacking. We conducted this systematic review and meta-analysis to compare the clinical outcomes of arthroscopic repair versus biceps tenotomy and tenodesis intervention.

Methods

The eight studies were acquired from PubMed, Medline, Embase, CNKI, and Cochrane Library. The data were extracted by two of the coauthors independently and were analyzed by RevMan 5.3. Mean differences (MDs), odds ratios (ORs), and 95% confidence intervals (CIs) were calculated. Cochrane Collaboration’s Risk of Bias Tool and Newcastle–Ottawa Scale were used to assess risk of bias.

Results

Eight studies including two randomized controlled trials (RCTs) and six observational studies were assessed. The methodological quality of the trials ranged from low to moderate. The pooled results of UCLA score, SST score, and complications showed that the differences were not statistically significant between the two interventions. The difference of ASES score and satisfaction rate was statistically significant between arthroscopic repair and biceps tenotomy and tenodesis intervention, and arthroscopic biceps tenotomy and tenodesis treatment was more effective. Sensitivity analysis proved the stability of the pooled results, and there were too less included articles to verify the publication bias.

Conclusions

Both arthroscopic repair and biceps tenotomy and tenodesis interventions had benefits in type II SLAP lesions. Arthroscopic biceps tenotomy and tenodesis treatment provides better clinical outcome in ASES score and satisfaction rate and comparable complications compared with arthroscopic repair treatment. In view of the heterogeneity and confounding factors, whether these conclusions are applicable should be further determined in future studies.

Type VIII SLAP Repair at Midterm Follow-Up: Throwers Have Greater Pain, Decreased Function, and Poorer Return to Play

PURPOSE

To evaluate and compare midterm outcomes and return to play (RTP) of throwers and nonthrowers who underwent type VIII SLAP repair.

METHODS

With 4-year minimum follow-up, stability, pain, range of motion (ROM), Kerlan-Jobe Orthopaedic Clinic (KJOC), and American Shoulder and Elbow Surgeons (ASES) scores; surgical satisfaction; and RTP were compared between throwing and nonthrowing athletes who underwent repair of type VIII SLAP lesions between 2003 and 2014.

RESULTS

46 patients (27 throwers and 19 nonthrowers) were included. The athletes were aged 24.2 ± 9.2 years at the time of surgery. The mean follow-up period was 6.6 ± 2.0 years. A significant improvement in stability, pain, ROM, KJOC, and ASES scores was seen after surgery in both throwers and nonthrowers (P < .05). When postoperative outcomes were compared, throwers had more pain (P = .047), decreased ROM (P = .03), lower KJOC scores (52.2 ± 24.0 in throwers vs 87.5 ± 18.8 in nonthrowers, P < .0001), and lower ASES scores (43.5 ± 7.1 in throwers vs 48.3 ± 3.0 nonthrowers, P = .02). There was no difference in stability (P = .06), surgical satisfaction (96.3% in throwers vs 100% in nonthrowers, P > .99), or overall RTP (70.4% in throwers vs 94.7% in nonthrowers, P = .06). However, throwers were less likely to RTP at their preoperative level (37.0% in throwers vs 73.7% in nonthrowers, P = .02).

CONCLUSIONS

Surgical repair of type VIII SLAP tears led to significant improvements in stability, pain, ROM, and outcome scores at midterm follow-up. Compared with nonthrowers, throwers had significantly more pain, less ROM, and worse function. Throwers were also less likely to RTP at their preoperative level. These findings suggest that type VIII SLAP tears should be repaired in all athletes because outcomes do improve, although throwers require specific counseling and expectation management regarding their ability to RTP at their preinjury level.

LEVEL OF EVIDENCE

Level III, therapeutic case-control study.

Normal Range of Humeral Head Positioning on the Glenoid on Magnetic Resonance Imaging: Validation through Comparison of Computed Tomography and Magnetic Resonance Imaging

Background

To determine the normal range of humeral head positioning on magnetic resonance imaging (MRI).

Methods

We selected normal subjects (64 patients; group A) to study the normal range of humeral head positioning on the glenoid by MRI measurements. To compare the MRI measurement method with the computed tomography (CT), we selected group B (70 patients) who underwent both MRI and CT. We measured the humeral-scapular alignment (HSA) and the humeral-glenoid alignment (HGA).

Results

The HSA in the control group was 1.47 ± 1.05 mm, and the HGA with and without reconstruction were 1.15 ± 0.65 mm and 1.03 ± 0.59 mm, respectively, on MRI. In the test group, HSA was 2.67 ± 1.47 mm and HGA with and without reconstruction was 1.58 ± 1.16 mm and 1.49 ± 1.08 mm, on MRI. On CT, the HSA was 1.72 ± 1.01 mm, and HGA with and without reconstruction were 1.54 ± 0.96 mm and 1.59 ± 0.93 mm, respectively. HSA was significantly different according to image modality (p=0.0006), but HGA was not significantly different regardless of reconstruction (p=0.8836 and 0.9234).

Conclusions

Although additional CT scans can be taken to measure decentering in patients with rotator cuff tears, reliable measurements can be obtained with MRI alone. When using MRI, it is better to use HGA, which is a more reliable measurement value based on the comparison with CT measurement (study design: Study of Diagnostic Test; Level of evidence II).

An Age and Activity Algorithm for Treatment of Type II SLAP Tears

Background

Type II SLAP tears predominantly occur in males between their third and fifth decades of life. The mechanism of injury is often repeated overheard activity but can also occur due to direct compression loads and traction injuries. The treatment options have changed over the years and include non-operative therapy, direct labral-biceps complex repair, and labral debridement with biceps tenodesis or tenotomy.

Objective

To review the existing literature on the management of Type II SLAP tears and provide clinical recommendations based on patient age and activity level.

Methods

A review of the existing literature through October 2017 investigating the management of Type II SLAP tears was performed. Emphasis was placed on distinguishing the outcomes based on age and activity level to provide an appropriate treatment algorithm.

Results

Patients with Type II SLAP tears should first be trialed with non-operative management and many patients will have a successful result with ability to return to their respective sports or activities. Surgical management should be considered if non-operative management does not provide symptomatic relief. Young, athletic, or high-demand patients should be treated with a SLAP repair while biceps tenodesis should be considered for older or worker's compensation patients. Patients undergoing revision surgery for a failed SLAP repair should be managed with biceps tenodesis.

Conclusion

Type II SLAP tears remain a difficult pathology to manage clinically, but the treatment indications are narrowing. The age and activity algorithm described in this review provides an effective method of managing this complex clinical condition.

Superior Labral Anterior to Posterior Tear Management in Athletes

Background:

The diagnosis and treatment of Superior Labrum Anterior to Posterior (SLAP) tears have been evolving and controversial. The lack of clear diagnostic criteria on physical examination, Magnetic Resonance Imaging (MRI), and arthroscopic evaluation clouds the issue. The high rate of MRI diagnosed SLAP lesions in the asymptomatic population of athletes and non-athletes warrants consideration when planning treatment for those with shoulder pain.

Objective:

To provide information on the evaluation, diagnosis and management of SLAP tears in athletes.

Methods:

The results of a structured non-operative rehabilitation program are discussed and compared to traditional surgical techniques. The evolution of the author’s treatment algorithm is presented. Results: The successful return to overhand throwing is more common with non-operative treatment than with surgical.

Conclusion:

A rehabilitation program focused on stretching the posterior capsule and correcting scapular posture is more successful than surgery for most throwers with SLAP lesions.

Anatomy and Biomechanics of the Unstable Shoulder

PURPOSE

To review the anatomy of the shoulder joint and of the physiology of glenohumeral stability is essential to manage correctly shoulder instability.

METHODS

It was reviewed a large number of recently published research studies related to the shoulder instability that received a higher Level of Evidence grade.

RESULTS

It is reviewed the bony anatomy, the anatomy and function of the ligaments that act on this joint, the physiology and physiopathology of glenohumeral instability and the therapeutic implications of the injured structures.

CONCLUSION

This knowledge allows the surgeon to evaluate the possible causes of instability, to assess which are the structures that must be reconstructed and to decide which surgical technique must be performed.

Arthroscopic Findings in Anterior Shoulder Instability

Background:

In the last years, basic research and arthroscopic surgery, have improved our understanding of shoulder anatomy and pathology. It is a fact that arthroscopic treatment of shoulder instability has evolved considerably over the past decades. The aim of this paper is to present the variety of pathologies that should be identified and treated during shoulder arthroscopy when dealing with anterior shoulder instability cases.

Methods:

A review of the current literature regarding arthroscopic shoulder anatomy, anatomic variants, and arthroscopic findings in anterior shoulder instability, is presented. In addition, correlation of arthroscopic findings with physical examination and advanced imaging (CT and MRI) in order to improve our understanding in anterior shoulder instability pathology is discussed.

Results:

Shoulder instability represents a broad spectrum of disease and a thorough understanding of the pathoanatomy is the key for a successful treatment of the unstable shoulder. Patients can have a variety of pathologies concomitant with a traditional Bankart lesion, such as injuries of the glenoid (bony Bankart), injuries of the glenoid labrum, superiorly (SLAP) or anteroinferiorly (e.g. anterior labroligamentous periosteal sleeve avulsion, and Perthes), capsular lesions (humeral avulsion of the glenohumeral ligament), and accompanying osseous-cartilage lesions (Hill-Sachs, glenolabral articular disruption). Shoulder arthroscopy allows for a detailed visualization and a dynamic examination of all anatomic structures, identification of pathologic findings, and treatment of all concomitant lesions.

Conclusion:

Surgeons must be well prepared and understanding the normal anatomy of the glenohumeral joint, including its anatomic variants to seek for the possible pathologic lesions in anterior shoulder instability during shoulder arthroscopy. Patient selection criteria, improved surgical techniques, and implants available have contributed to the enhancement of clinical and functional outcomes to the point that arthroscopic treatment is considered nowadays the standard of care.

Anteroposterior translation of the glenohumeral joint in various pathologies: differences between shoulder MRI in the adducted neutral rotation and abducted externally rotated positions

PURPOSE

The present study was performed to determine the translation of the glenohumeral joint in patients with and without shoulder lesions by comparing the magnetic resonance images obtained in the conventional adducted neutral rotation position with those obtained in the abducted externally rotated position.

METHODS

Two hundred and eighty-five consecutive shoulders without rotator cuff tears that had been subjected to magnetic resonance imaging (MRI) without arthrography in the abducted externally rotated position were reviewed retrospectively. Among them, 50 shoulders without pathology were selected at random to be compared with three shoulder pathology groups, comprising shoulders with superior labrum, anterior-to-posterior (SLAP) lesions without range of motion (ROM) limitation (group I, 47 shoulders), with massive rotator cuff tears without ROM limitation (group II, 20 shoulders), and with full-thickness subscapularis tendon tears without ROM limitation (group III, 20 shoulders). Glenohumeral translation in the anterior-to-posterior direction relative to the glenoid face was evaluated using a method based on the glenohumeral contact point (CP) and humeral head centre (HHC) in the adducted neutral rotation and abducted externally rotated views, which were measured by three orthopaedic surgeons. For each shoulder, the differences in translation for the glenohumeral CP and HHC between the adducted neutral rotation and abducted externally rotated views were calculated as relative posterior translation in millimetres.

RESULTS

The differences in ΔCP and ΔHHC between group I and the normal control group were not statistically significant. The differences in ΔCP (P = 0.001) and ΔHHC (P = 0.001) between group II and the normal control group were statistically significant. Additionally, the differences in ΔCP and ΔHHC between group III and the normal control group were not statistically significant.

CONCLUSIONS

The MRI in abducted externally rotated view in patients with SLAP lesions or full-thickness subscapularis tendon tears diagnosed by conventional MRI alone showed no significant glenohumeral posterior translation relative to the adducted neutral rotation view in the present study. However, the abducted externally rotated view in patients with massive rotator cuff tears showed significant glenohumeral anterior translation relative to the adducted neutral rotation view.

Biomechanical characterization of unicortical button fixation: a novel technique for proximal subpectoral biceps tenodesis

PURPOSE

Proximal biceps tenodesis is one method for treating biceps-related pain. Tenodesis protects the length-tension relationship of the biceps muscle, maintains strength, and provides a better cosmetic appearance than tenotomy. The purpose of this investigation was to compare the mechanical properties of a unicortical metal button and an interference screw in proximal biceps tenodesis.

METHODS

Six pairs of fresh-frozen shoulders were dissected, leaving the proximal biceps tendon as a free graft. On each pair of shoulders, a biceps tenodesis was performed using an interference screw or a unicortical metal button. The specimens were mounted and a cyclic load (10-60 N) was applied at 1 Hz for 200 cycles, followed by an axial load to failure. The displacement, ultimate load to failure, and mode of failure were recorded.

RESULTS

Displacement in response to cyclic loading was 3.7 ± 2.2 mm for the interference screw and 1.9 ± 1.0 mm for the cortical button (P = 0.03). Load at failure for the interference screw was 191 ± 64 N (stiffness: 24 ± 11 N/mm) and 183 ± 61 N (stiffness: 24 ± 7. N/mm) for the unicortical button (P = n.s. for both cases).

CONCLUSIONS

As a novel technique for subpectoral biceps tenodesis, a unicortical button demonstrated significantly less displacement in response to cyclic loading than the interference screw. The ultimate load to failure and stiffness for the two methods were not different. In this way, a unicortical button may provide a reliable alternative method of fixation with a potentially lower risk of post-operative humeral fracture and a construct that permits early mobilization following biceps tenodesis.

Assessment and treatment strategies for rotator cuff tears

Tears of the rotator cuff are common and becoming an increasingly frequent problem. There is a vast amount of literature on the merits and limitations of the various methods of clinical and radiological assessment of rotator cuff tears. This is also the case with regard to treatment strategies. Certain popular beliefs and principles practiced widely and the basis upon which they are derived may be prone to inaccuracy. We provide an overview of the historical management of rotator cuff tears, as well as an explanation for how and why rotator cuff tears should be managed, and propose a structured methodology for their assessment and treatment.

Surgical treatment of isolated type II superior labrum anterior-posterior (SLAP) lesions: repair versus biceps tenodesis

BACKGROUND

It is still unclear which patients with isolated type II superior labrum anterior-posterior (SLAP) lesions benefit from either superior labral repair or biceps tenodesis. This study evaluates the indications and outcomes of patients with isolated type II SLAP lesions who have undergone either procedure.

METHODS

A retrospective analysis was performed of patients who had surgery for an isolated type II SLAP lesion between 2008 and 2011. There were 25 patients: 15 underwent biceps tenodesis, with a mean follow-up of 31 months (range, 26-43 months), and 10 underwent SLAP repair, with a mean follow-up of 35 months (range, 25-52 months). The mean age was 47 years (range, 30-59 years) in the tenodesis group and 31 years (range, 21-43 years) in the repair group.

RESULTS

At latest follow-up, both groups showed significant improvements in subjective shoulder value and pain score. No difference was observed in American Shoulder and Elbow Surgeons score (93.0 vs 93.5, P = .45), patient satisfaction (93% vs 90%, P = .45), or return to preinjury sporting level (73% vs 60%, P = .66). Analysis of the indications for treatment showed that in the large majority, tenodesis was performed in older patients (>35 years) and patients who showed degenerative or frayed labrums whereas SLAP repairs were performed in younger and more active patients with healthy-appearing labral tissue. There was only 1 failure in the tenodesis group, and in the SLAP repair group, there were 2 cases of postoperative stiffness; all were treated nonoperatively.

CONCLUSION

In this study, we show that both biceps tenodesis and SLAP repair can provide good to excellent results if performed in appropriately selected patients with isolated type II SLAP lesions.

Superior labrum anterior-to-posterior repair incidence: a longitudinal investigation of community and academic databases

BACKGROUND

Superior labrum anterior-to-posterior (SLAP) lesion repair is controversial regarding indications and potential complications.

METHODS

Databases were used to determine the SLAP repair incidence compared with all orthopaedic procedures over a period of 10 years. In part A, the New York Statewide Planning and Research Cooperative System ambulatory surgery database was investigated from 2002 to 2009. In part B, the California Office of Statewide Health Planning and Development ambulatory surgery database was investigated from 2005 to 2009. In part C, the American Board of Orthopaedic Surgery (ABOS) database was investigated from 2003 to 2010.

RESULTS

In part A, from 2002 to 2009, there was a 238% increase in SLAP repair volume compared with a 125% increase in all orthopaedic procedures. In part B, from 2005 to 2009, there was a 20.17% increase in SLAP repair volume compared with a decrease of 13.64% in all orthopaedic procedures. In part C, among candidates performing at least 1 SLAP repair, there was no statistically significant difference in likelihood of performing a SLAP repair (95% confidence interval, 0.973-1.003) in 2010 as compared with 2003 (P > .10).

CONCLUSIONS

There has been a significant increase in the incidence of SLAP repairs in the past 10 years in statewide databases. This pattern was not seen in the ABOS database, in which the annual volume of SLAP repairs remained stable over the same period. This suggests that SLAP lesions have been over-treated with surgical repair but that part II ABOS candidates are becoming more aware of the need to narrow indications.

LEVEL OF EVIDENCE

Epidemiology study, database analysis.

Superior labral anterior posterior lesions of the shoulder

Superior labrum anterior and posterior (SLAP) lesion is of fairly recent description and its understanding is rapidly evolving. Its incidence and need for surgical treatment has increased exponentially in line with the increase in shoulder arthroscopies. It is of particular importance in the elite over head athlete and the young. A range of arthroscopic techniques and devices have been described with good functional results. The ability to return to pre injury level of sports remains a concern.

Glenohumeral contact pressure in a simulated active compression test using cadaveric shoulders

BACKGROUND

The active compression test has been described to detect superior labrum anterior and posterior (SLAP) lesions. Some have speculated that contact between the lesser tuberosity and the superior glenoid in the testing position causes a positive test. This study evaluated the location of peak glenohumeral contact pressures during a simulated active compression test in a cadaveric model with and without SLAP lesions.

MATERIALS AND METHODS

Six specimens were tested. A pressure sensor was used to record glenohumeral contact, and a motion analysis system was used to measure humeral head translation. Contact pressures and translations were measured during serial deltoid and biceps loads. These were repeated for small and large SLAP lesions.

RESULTS

There was a notable shift in the location of peak contact pressure from the anterior-inferior glenoid to the anterior-superior glenoid with increasing deltoid load. Deltoid loading translated the humeral head posteriorly relative to the glenoid. Conversely, biceps loads countered the pull of the deltoid only when the biceps load was greater than the deltoid load. The SLAP tears did not significantly alter the degree of humeral head translation or location of the contact pressures.

CONCLUSIONS

In the active compression test, the posterior capsule is taut and the anterior capsule is lax, which permits the deltoid to translate the humeral head posteriorly. This shift in the peak contact pressure to the superior glenoid may elicit a positive active compression test.

LEVEL OF EVIDENCE

Basic Science Study, Biomechanics, Cadaver Model.

Relationship between the extent of labral lesions and the frequency of glenohumeral dislocation in shoulder instability

PURPOSE

This study aimed to evaluate the relationship between the extent of the labral lesion and the frequency of glenohumeral dislocation in patients with shoulder instability.

METHODS

Ninety-three patients, who underwent surgical treatment at our clinic for chronic anterior shoulder dislocation, were selected and divided into 3 groups (group I: only Bankart lesion; group II: Bankart and SLAP lesions; group III: circumferential-labral lesion). The pre-operative frequency of dislocation, intraoperative findings, operation time, post-operative clinical score, and range of motion 2 years after surgery were analysed and compared among the 3 groups.

RESULTS

The time interval from the initial dislocation to operation was significantly shorter in group III than in groups I and II (P = 0.034 and P = 0.046, respectively). The median number of preoperative dislocations was also significantly less in group III than in groups I and II (P = 0.025 and P = 0.044, respectively). In all groups, the clinical scores (Constant, Rowe, and visual analogue scale) improved significantly post-operatively, and there were no significant differences in the scores between the different groups. All patients returned to work, and most patients returned to their preoperative sports activity levels.

CONCLUSION

The extent of the labral lesion is not always related to the number of dislocations; therefore, treatment should not be based on this.

LEVEL OF EVIDENCE

Retrospective comparative study, Level III.

The role of negative intraarticular pressure and the long head of biceps tendon on passive stability of the glenohumeral joint

BACKGROUND

The purpose of this study was to determine the effect of intraarticular pressure and the long head of biceps (LHB) tendon on passive translations of the glenohumeral (GH) joint. Tenotomy or tenodesis of the LHB are common procedures but the consequences on shoulder stability are unclear.

METHODS

A novel shoulder laxity testing rig permitting six degrees of freedom of motion was used to test passive translations in anterior, posterior, superior, and inferior directions in 10 cadaveric shoulders. Specimens were tested in neutral rotation with 0°, 30°, 60°, or 90° of GH abduction in the scapular plane. Translation loads up to 30N were applied, and displacements measured in an intact joint, vented joint and with the biceps tendon loaded (20N).

RESULTS

The GH joint was most lax at 30° GH abduction. Venting of the joint increased translations in all positions and directions (mean ± standard error of the mean), the greatest difference was 12.5 (3.9) mm in the anterior-posterior direction and 7.5 (3.9) mm in the SI direction. Loading the LHB tendon with 20N decreased translations in all directions. The largest difference was observed in the anterior direction, 13.9 (2.8) mm (P < .0005) and inferior direction, 12.0 (2.8) mm (P < .0005).

CONCLUSION

Negative intraarticular pressure and the LHB contribute significantly to overall passive stability of the GH joint. Surgical division or transfer of the LHB tendon may impact on joint stability and function.

The influence of superior labrum anterior to posterior (SLAP) repair on restoring baseline glenohumeral translation and increased biceps loading after simulated SLAP tear and the effectiveness of SLAP repair after long head of biceps tenotomy

HYPOTHESIS

Biomechanical studies have shown increased glenohumeral translation and loading of the long head biceps (LHB) tendon after superior labrum anterior to posterior (SLAP) tears. This may explain some of the typical clinical findings, including the prevalence of humeral chondral lesions, after SLAP lesions. The first hypothesis was that SLAP repair could restore the original glenohumeral translation and reduce the increased LHB load after SLAP lesions. The second hypothesis was that SLAP repair after LHB tenotomy could significantly reduce the increased glenohumeral translation.

MATERIALS AND METHODS

Biomechanical testing was performed on 21 fresh frozen human cadaveric shoulders with an intact shoulder girdle using a sensor-guided industrial robot to apply 20 N of compression in the joint and 50 N translational force at 0°, 30°, and 60° of abduction. LHB loading was measured by a load-cell with 5 N and 25 N preload. Type IIC SLAP lesions were created arthroscopically, and a standardized SLAP repair was done combined with or without LHB tenotomy.

RESULTS

No significant difference of glenohumeral translation and increased LHB load in SLAP repair compared with the intact shoulder was observed under 5 N and 25 LHB preload, except for anterior translation under 25 N LHB preload. After LHB tenotomy after SLAP lesions, no significant difference of translation was observed with or without SLAP repair.

CONCLUSIONS

SLAP repair without associated LHB tenotomy helps normalize glenohumeral translation and LHB loading. The stabilizing effect of the SLAP complex is dependent on the LHB. After biceps tenotomy, SLAP repair does not affect glenohumeral translation.

Effects of combined anterior and posterior plication of the glenohumeral ligament complex for the repair of anterior glenohumeral instability: a biomechanical study

BACKGROUND

Arthroscopic repair techniques for anterior instability most commonly address only the anterior band of the inferior glenohumeral ligament. This study quantitatively evaluated and compared the combined anterior and posterior arthroscopic plication by repairing both the anterior and posterior bands of the inferior glenohumeral ligament with the anterior arthroscopic plication alone.

MATERIALS AND METHODS

Six cadaveric shoulders were tested in 60° of glenohumeral abduction with 22 N of compressive force in the coronal plane for intact, after anterior capsular stretching, after anterior repair, and after posterior arthroscopic repair. Range of motion, glenohumeral translation, and glenohumeral kinematics throughout the rotational range of motion were measured with a MicroScribe 3DLX (Immersion, San Jose, CA, USA). Glenohumeral contact pressure and area were measured with a pressure measurement system (Tekscan Inc, South Boston, MA, USA).

RESULTS

Stretching the anterior capsule significantly increased external rotation and anterior translation (P < .05). After anterior plication, external rotation was restored to the intact condition, and anterior translation was significantly decreased compared with stretched condition (P < .05). The combined anterior and posterior plication significantly decreased internal rotation compared with the intact condition. The anterior plication shifted the humeral head posterior in external rotation, whereas the combined anterior and posterior plication shifted the humeral head anterior in internal rotation (P < .05). Both repairs led to a decrease in glenohumeral contact area at 45° external rotation (P < .07).

CONCLUSIONS

The addition of a posterior plication to anterior plication for anterior instability has no biomechanical advantage over a typical arthroscopic anterior repair for anterior glenohumeral instability.

Combined lesions of the glenoid labrum

Advances in shoulder arthroscopy and improved understanding of the pathoanatomy following shoulder instability have led to increased recognition of combined lesions of the glenoid labrum. Although the diagnosis of combined labral tears is often made with physical examination and magnetic resonance imaging, combined tears can be discovered intraoperatively. A high index of suspicion is necessary, especially in the setting of chronic recurrent shoulder instability or previous failed labral repair. Over a 6-year period at a military institution, combined labral repairs comprised 37% of all patients undergoing any labral repair. With accurate identification of all labral pathology and a systematic approach to labral repair, successful outcomes can be achieved.

Role of the long head of the biceps brachii muscle in axial humeral rotation control

This anatomical and biomechanical study focuses on the specific influence of the long head of biceps brachii muscle in controlling axial humeral rotation. The tendon of the long head of the biceps brachii (biceps tendon) is shown to either facilitate or restrict axial humeral rotation. Its effect on axial humeral rotation is strongly related to firstly the amount of biceps tendon load, secondly glenohumeral scapular plane elevation, and thirdly the rotatory position of the humerus. At 0° glenohumeral elevation, biceps tendon load caused an increase of internal humeral rotation, from 0° at 2.25 N biceps tendon load to 23° at 82.25 N. Under 45° glenohumeral elevation, biceps tendon load can restrict and facilitate as well internal and external axial humeral rotation, increasing the rotatory range of motion. Above 45° glenohumeral elevation biceps tendon load restricts internal and external axial humeral rotation, increasing actively joint stability by increasing torsional rigidity. These findings on the function of the biceps tendon could have consequences for the clinical interpretation. In the elevated arm position, extreme rotation loads the long head of the biceps tendon and may turn out to biceps or bicepslabrum complex injuries.