What went wrong and what was done about it: pitfalls in the treatment of common shoulder surgery

Functional Anatomy and Biomechanics of Shoulder Instability

The glenohumeral joint is the least congruent and least constrained joint with a complex relationship of static and dynamic stabilizers to balance its native mobility with functional stability. In the young athlete, anterior shoulder instability is multifactorial and can be a challenge to treat, requiring a patient-specific treatment approach. Surgical decision-making must consider patient-specific factors such as age, sport activity and level, underlying ligamentous laxity, and goals for return to activity, in addition to careful scrutiny of the underlying pathology to include humeral and glenoid bone loss and surrounding scapular bone morphology.

Open Anatomic Coracoclavicular Ligament Reconstruction for Acromioclavicular Joint Injuries

Open reconstruction of the coracoclavicular (CC) and acromioclavicular (AC) ligaments results in excellent reduction of severely displaced AC dislocations, most commonly Grades III and V. Anatomic CC reconstruction through clavicular bone tunnels can prevent vertical instability, whereas the addition of an acromial limb of the graft can increase horizontal stability. Autograft tendon is preferred in the young athletic group of collision sports participants, although allograft has had acceptable results. Accessory fixation may be placed to protect the graft during healing, or for severe instability, especially for athletes involved in contact sports.

Remplissage for Anterior Shoulder Instability: History, Indications, and Outcomes

Remplissage is a nonanatomic capsulotenodesis of the infraspinatus tendon used to fill engaging or "off-track" Hill-Sachs lesions in patients at high risk of recurrent instability with isolated Bankart repair. Indications for remplissage are expanding, as the importance of subcritical bone loss and the glenoid track on patient outcomes and recurrence rates continues to be investigated. Remplissage is also suggested in patients at high risk of recurrent instability following isolated anterior labral repair, such as collision and contact athletes with Hill-Sachs lesions that have not reached the threshold of "off track." Multiple arthroscopic remplissage techniques exist including, more recently, knotless techniques.

Modified Mason-Allen Knot for Arthroscopic Complex Bankart Lesion Repair in Recurrent Anterior Shoulder Instability

The arthroscopic Bankart repair is a safe and reliable procedure for the treatment of recurrent shoulder instability for the well-indicated patient. Many repair techniques have been described to restore both labral height and width and recreate a dynamic concavity-compression effect. The modified Mason-Allen knot was first described for rotator cuff tear repair and consists of a horizontal mattress knot with a simple vertical stitch on the same anchor. The purpose of this work is to present the use of the modified Masen-Allen knot for the repair of the capsular labral complex during an arthroscopic Bankart procedure.

Accuracy of Currently Available Methods in Quantifying Anterior Glenoid Bone Loss: Controversy Regarding Gold Standard-A Systematic Review

PURPOSE

To determine the accuracy of glenoid bone loss-measuring methods and assess the influence of the imaging modality on the accuracy of the measurement methods.

METHODS

A literature search was performed in the PubMed (MEDLINE), Embase, and Cochrane databases from 1994 to June 11, 2019. The guidelines and algorithm of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) were used. Included for analysis were articles reporting the accuracy of glenoid bone loss-measuring methods in patients with anterior shoulder instability by comparing an index test and a reference test. Furthermore, articles were included if anterior glenoid bone loss was quantified using a ruler during arthroscopy or by measurements on plain radiograph(s), computed tomography (CT) images, or magnetic resonance images in living humans. The risk of bias was determined using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool.

RESULTS

Twenty-one studies were included, showing 17 different methods. Three studies reported on the accuracy of methods performed on 3-dimensional CT. Two studies determined the accuracy of glenoid bone loss-measuring methods performed on radiography by comparing them with methods performed on 3-dimensional CT. Six studies determined the accuracy of methods performed using imaging modalities with an arthroscopic method as the reference. Eight studies reported on the influence of the imaging modality on the accuracy of the methods. There was no consensus regarding the gold standard. Because of the heterogeneity of the data, a quantitative analysis was not feasible.

CONCLUSIONS

Consensus regarding the gold standard in measuring glenoid bone loss is lacking. The use of heterogeneous data and varying methods contributes to differences in the gold standard, and accuracy therefore cannot be determined.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II, III, and IV studies.

Comparison of Clinical and Radiographic Outcomes of Vertical Simple Stitch Versus Modified Mason-Allen Stitch in Arthroscopic Bankart Repairs: A Prospective Randomized Controlled Study

BACKGROUND

In spite of the probable advantages of Bankart repair with modified Mason-Allen technique, there has been no study to evaluate the clinical outcomes of the modified Mason-Allen technique for Bankart repair.

PURPOSE

To prospectively compare the anatomic and clinical outcomes between the vertical simple stitch and the modified Mason-Allen stitch with respect to the labral height, retear rate, redislocation/apprehension, and various functional outcome scores.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 2.

METHODS

Patients who underwent arthroscopic Bankart repair with double-loaded suture anchors were randomly allocated to 1 of 2 groups: the vertical simple stitch method (SS; n = 45) or the Bankart repair using modified Mason-Allen technique (BRUMA; n = 41). All patients underwent computed tomography arthrography at 6 months postoperatively and various functional outcome measurements at least 2 years postoperatively. The labral height and width at the 3-, 4-, and 5-o'clock positions were measured preoperatively and at 6 months after surgery on axial computed tomography arthrography; the redislocation/apprehension rate, the retear rate, and various functional outcome scores were evaluated at each follow-up visit.

RESULTS

Postoperative labral height and width were significantly increased at all locations (all P < .001) in both groups, but they were not statistically different between groups (all P > .05). Two patients in the SS group (4.4%) and 2 in the BRUMA group (4.9%) experienced redislocation after surgery, and 4 patients in the SS group (8.9%) and 2 in the BRUMA group (4.9%) group showed apprehension after surgery. Additionally, 5 patients in the SS group (11.1%) and 2 in the BRUMA group (4.9%) showed retear at 6 months ( P = .239). There were no differences in any functional outcome scores (all P > .05).

CONCLUSION

There was no difference in the radiologic outcomes at 6 months and the clinical outcomes assessed at least 2 years after surgery between the groups.

Management of Complex Anterior Shoulder Instability: a Case-Based Approach

PURPOSE OF THE REVIEW

The goal of this review is to provide a guide on surgical decision-making options for complex anterior shoulder instability using a case-based approach.

RECENT FINDINGS

Arthroscopic Bankart repair is well documented for having successful outcomes in patients with isolated labral tear involvement with minimal bone loss. Latarjet is a generally accepted procedure in patients with 20-30% glenoid bone loss. When bone loss exceeds that which cannot be managed through Latarjet, a range of options exist and are highly dependent upon the extent of osseous deficiency on both the glenoid and humeral sides, surgeon experience, and patient-specific factors. The use of reverse total shoulder arthroplasty for the management of chronic locked shoulder dislocations has been described as a successful management option. Treatment options for complex anterior shoulder instability range widely based on patients' presenting exam, surgical history, amount of glenoid bone loss, size of Hill-Sachs lesion, and surgeon preference. When selecting the appropriate surgical intervention, the treating surgeon must consider the patient history, physical exam, and preoperative imaging along with patient expectations.

Critical Value of Anterior Glenoid Bone Loss That Leads to Recurrent Glenohumeral Instability After Arthroscopic Bankart Repair

BACKGROUND

Generally, a glenoid bone loss greater than 20% to 25% is considered critical for poor surgical outcomes after a soft tissue repair. However, recent studies have suggested that the critical value should be lower.

PURPOSE

To determine the critical value of anterior glenoid bone loss that led to surgical failure in patients with anterior shoulder instability.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

The study included 169 patients with anterior glenoid erosion. The percentage of glenoid erosion was calculated as the ratio of the glenoid loss width and the glenoid width to the diameter of the outer-fitting circle based on the inferior portion of the glenoid contour. The critical value of the glenoid bone loss was analyzed by means of receiver operating characteristic (ROC) curve analysis. Patients were divided into 2 groups based on the amount of glenoid bone loss: group A (less than the critical value) and group B (more than the critical value). Patients evaluated their shoulder function as a percentage of their preinjury level using the Single Assessment Numeric Evaluation (SANE) score, and postoperative clinical outcomes were assessed with the American Shoulder and Elbow Surgeons (ASES) score and Rowe score. Surgical failure was defined as the need for revision surgery or the presence of subjective symptoms of instability.

RESULTS

The optimal critical value of glenoid bone loss was 17.3% (area under the curve = 0.82; 95% confidence interval, 0.73-0.91; P < .001; sensitivity 75%; specificity 86.6%). Group A and B contained 134 and 35 patients, respectively. Shoulder functional scores were significantly lower in group B than in group A ( P < .001). Five patients (3.7%) in group A and 15 (42.9%) in group B had surgical failure ( P < .001). The SANE score was significantly lower in group B (83.8 ± 12.1) than in group A (92.9 ± 4.7, P = .001).

CONCLUSION

An anterior glenoid bone loss of 17.3% or more with respect to the longest anteroposterior glenoid width should be considered as the critical amount of bone loss that may result in recurrent glenohumeral instability after arthroscopic Bankart repair.

Hemiarthroplasty versus reverse shoulder arthroplasty for treatment of proximal humeral fractures: a meta-analysis

BACKGROUND

We performed a meta-analysis of studies with at least Level IV evidence to compare outcomes between hemiarthroplasty and reverse shoulder arthroplasty for the treatment of proximal humeral fractures.

METHODS

Three electronic databases (PubMed, Cochrane, and EMBASE) were searched. The quality of each study was investigated, and data on radiographic and functional outcomes were extracted and analyzed.

RESULTS

The analysis included 1 Level I study, 1 Level II study, 3 Level III studies, and 2 Level IV studies. Reverse shoulder arthroplasty was more favorable than hemiarthroplasty in forward elevation (P < .001), abduction (P < .001), tuberosity healing (P = .002), Constant score (P < .001), American Shoulder and Elbow Surgeons score (P < .001), and Disabilities of the Arm, Shoulder and Hand score (P = .001). Only external rotation (P = .85) was not in favor of reverse shoulder arthroplasty.

CONCLUSIONS

The available literature suggests that reverse shoulder arthroplasty performed to address complex proximal humeral fractures might result in more favorable clinical outcomes than hemiarthroplasty performed for the same indication.

Redefining "Critical" Bone Loss in Shoulder Instability: Functional Outcomes Worsen With "Subcritical" Bone Loss

BACKGROUND

Glenoid bone loss is a common finding in association with anterior shoulder instability. This loss has been identified as a predictor of failure after operative stabilization procedures. Historically, 20% to 25% has been accepted as the "critical" cutoff where glenoid bone loss should be addressed in a primary procedure. Few data are available, however, on lesser, "subcritical" amounts of bone loss (below the 20%-25% range) on functional outcomes and failure rates after primary arthroscopic stabilization for shoulder instability.

PURPOSE

To evaluate the effect of glenoid bone loss, especially in subcritical bone loss (below the 20%-25% range), on outcomes assessments and redislocation rates after an isolated arthroscopic Bankart repair for anterior shoulder instability.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Subjects were 72 consecutive anterior instability patients (73 shoulders) who underwent isolated anterior arthroscopic labral repair at a single military institution by 1 of 3 sports medicine fellowship-trained orthopaedic surgeons. Data were collected on demographics, the Western Ontario Shoulder Instability (WOSI) score, Single Assessment Numeric Evaluation (SANE) score, and failure rates. Failure was defined as recurrent dislocation. Glenoid bone loss was calculated via a standardized technique on preoperative imaging. The average bone loss across the group was calculated, and patients were divided into quartiles based on the percentage of glenoid bone loss. Outcomes were analyzed for the entire cohort, between the quartiles, and within each quartile. Outcomes were then further stratified between those sustaining a recurrence versus those who remained stable.

RESULTS

The mean age at surgery was 26.3 years (range, 20-42 years), and the mean follow-up was 48.3 months (range, 23-58 months). The cohort was divided into quartiles based on bone loss. Quartile 1 (n = 18) had a mean bone loss of 2.8% (range, 0%-7.1%), quartile 2 (n = 19) had 10.4% (range, 7.3%-13.5%), quartile 3 (n = 18) had 16.1% (range, 13.5%-19.8%), and quartile 4 (n = 18) had 24.5% (range, 20.0%-35.5%). The overall mean WOSI score was 756.8 (range, 0-2097). The mean WOSI score correlated with SANE scores and worsened as bone loss increased in each quartile. There were significant differences (P < .05) between quartile 1 (mean WOSI/SANE, 383.3/62.1) and quartile 2 (mean, 594.0/65.2), between quartile 2 and quartile 3 (mean, 839.5/52.0), and between quartile 3 and quartile 4 (mean, 1187.6/46.1). Additionally, between quartiles 2 and 3 (bone loss, 13.5%), the WOSI score increased to rates consistent with a poor clinical outcome. There was an overall failure rate of 12.3%. The percentage of glenoid bone loss was significantly higher among those repairs that failed versus those that remained stable (24.7% vs 12.8%, P < .01). There was no significant difference in failure rate between quartiles 1, 2, and 3, but there was a significant increase in failure (P < .05) between quartiles 1, 2, and 3 (7.3%) when compared with quartile 4 (27.8%). Notably, even when only those patients who did not sustain a recurrent dislocation were compared, bone loss was predictive of outcome as assessed by the WOSI score, with each quartile's increasing bone loss predictive of a worse functional outcome.

CONCLUSION

While critical bone loss has yet to be defined for arthroscopic Bankart reconstruction, our data indicate that "critical" bone loss should be lower than the 20% to 25% threshold often cited. In our population with a high level of mandatory activity, bone loss above 13.5% led to a clinically significant decrease in WOSI scores consistent with an unacceptable outcome, even in patients who did not sustain a recurrence of their instability.

Managing and recognizing complications after treatment of acromioclavicular joint repair or reconstruction

Complications of the acromioclavicular joint injuries can occur as a result of the injury itself, conservative management, or surgical treatment. Fortunately, the majority of acromioclavicular surgeries utilizing modern techniques and instrumentation result in successful outcomes. However, clinical failures do occur with frequency. The ability to identify the causative factor of failures makes revision surgery more likely to be successful. The purposes of this review are to highlight common problems that can occur following acromioclavicular joint surgery and discuss techniques that can be utilized in revision surgery.