Soft tissue-based surgical techniques for treatment of posterior shoulder instability

Does glenoid bone loss accompany posterior shoulder instability with only labral tear? A magnetic resonance imaging-based study

BACKGROUND

The primary aim of this study was to investigate bone loss in the glenoid with magnetic resonance imaging in posterior shoulder instability with only a labral tear.

METHODS

A total of 76 patients operated on because of posterior and anteroposterior shoulder instability only with a labral tear between 2006 and 2019 (n = 40 and n = 36, respectively) were included in this study. The instability type, a presence of an additional superior labrum anteroposterior (SLAP) lesion, the number of dislocations, and the magnetic resonance imaging-based measurements (the glenoid diameter and the bone defect size in the glenoid, the Hill-Sachs lesion [HSL] and the reverse HSL [rHSL] length, the angle and the arc length of HSL and rHSL, and the humerus head diameter and its area) were analyzed.

RESULTS

The size of the anterior glenoid defect, the rHSL measurements (length, angle, and arc length), and the ratio of the anterior glenoid defect size to the glenoid diameter were significantly higher for anteroposterior instability (P < .01) cases. There was no significant difference (P = .49, .64, and .82, respectively) for the presence of an additional SLAP pathology, the glenoid diameter, the posterior glenoid defect, and the ratio of the posterior glenoid defect size to the glenoid diameter in posterior and anteroposterior instability groups. The increased number of dislocations was associated with increased rHSL length and total arc length (P = .04 and .03, respectively). An additional SLAP lesion in posterior shoulder instabilities was not associated with the bone defect size (P = .29).

CONCLUSION

Although the posterior shoulder instability with only a labral tear is likely to cause a bone defect, we have shown that the instability is not expected to be caused by the bone defect. Therefore, this study points out that only soft tissue repair without considering the bone defect could be promising in this patient group.

The O'Brien test demonstrates a higher diagnostic value in identifying posteroinferior labral tears than superior labral anterior to posterior (SLAP) tears

Background

The primary aim was to determine the diagnostic value of the O'Brien test in localizing labral tears of the shoulder.

Methods

A consecutive series of patients electing for labral repair between January 2005 and March 2021 were included in this retrospective study. Inclusion criteria were as follows: (1) any patient with a labral tear who was elected for arthroscopic labral repair and (2) had documentation of the O'Brien test in the preoperative evaluation. Exclusion criteria were patients that had a negative arthrographically enhanced computed tomography or magnetic resonance imaging scan. During arthroscopy, the localization and extension of the labral tear was documented in a standardized 12-o'clock configuration. Anteroinferior, posteroinferior, superior labrum anterior to posterior (SLAP), and combined labral tears were documented. The sensitivity, specificity, positive and negative predictive values, accuracy, positive and negative likelihood ratios, receiver operating characteristic curve, and area under the curve were calculated to determine the diagnostic value.

Results

The cohort consisted of 271 patients (77% male) and included 105 anteroinferior, 86 posteroinferior, 46 SLAP, and 32 combined parts of the labrum. The mean age at time of surgery was 30 (±10.2) years. The O'Brien test was positive in 142 (52%) patients and showed the highest sensitivity and specificity for the posteroinferior tears (83% and 62%) compared to the anteroinferior (16% and 25%), combined labral parts (69% and 50%), and SLAP (65% and 50%) tears. In addition, receiver operating characteristic-analysis demonstrated a significantly higher area under the curve for posteroinferior tears compared to the other tears (P < .001).

Conclusion

The O'Brien test demonstrates more diagnostic value for posteroinferior tears than other labral tears. This includes the SLAP tear, for which the O'Brien test was originally designed.

Clinical Relevance

These findings are helpful towards reinterpreting the O'Brien test as well as diagnosing, and more specifically localizing labral tears in clinics.

Posterior Shoulder Dislocation with Engaging Reverse Hill-Sachs Lesion: A Retrospective Study of Ten Patients Treated with Arthroscopy or Open Reduction and Stabilization

This study compares two surgical techniques used to treat patients with posterior shoulder dislocation with an engaging reverse Hill–Sachs lesion. We assessed ten patients who were treated at the Surgical Orthopedic and Traumatological Institute (ICOT) of Latina and the Clinic of Orthopedic and Traumatological Surgery of the ASST Sette Laghi of Varese between 2016 and 2019. The patients were divided into two groups: the first comprising six patients who underwent the open surgery McLaughlin procedure as modified by Neer, the second including four patients who underwent the arthroscopic McLaughlin procedure. All patients received postoperative rehabilitation to achieve the best possible functional recovery of the affected shoulder. We then assessed the shoulder range of motion, the pain level, and the impact on quality of life with four tests: the Constant Scale, the Simple Shoulder Test (SST), the OXFORD Scale, and The University of California—Los Angeles (UCLA) Shoulder Scale. The mean scores of the first group were: 81.3 ± 9.8 SD (Constant Scale), 10.8 ± 1.06 SD (SST), 42.5 ± 5.4 SD (Oxford Scale), 30.8 ± 3.02 SD (UCLA Shoulder Scale); we calculated the following mean scores in the second group: 80.25 ± 4.1 SD (Constant Scale), 11.5 ± 0.8 SD (SST), 42 ± 4.06 SD (Oxford Scale), 32 ± 2.9 SD (UCLA Shoulder Scale). We found no significant differences between the two groups.

Arthroscopic "Bone Block Cerclage" Technique for Posterior Shoulder Instability

Many open and arthroscopic techniques have been described to treat posterior glenohumeral instability. Multifactorial features of posterior shoulder instability pathoanatomy and varied patient characteristics have challenged the understanding of this condition and have led to dissimilar results, without a strong consensus for the most adequate technique to treat it. We describe an arthroscopic anatomical metal-free posterior glenoid reconstruction technique, using a tricortical iliac crest allograft with 2 ultra-high strength sutures (FiberTape Cerclage System; Arthrex, Naples, FL) with concomitant posterior capsulolabral complex reconstruction procedure.

Arthroscopic Management of Locked Posterior Shoulder Dislocations

Locked posterior shoulder dislocations occur relatively uncommonly but pose aunique array of challenges for the treating surgeon. Posterior labral detachments and capsular damage along with reverse Hill-Sachs lesions are commonly present in these patients and must often be addressed at the time of surgical intervention. Multiple open and arthroscopic procedures that address these pathologic lesions have been described. Arthroscopic shoulder stabilization for patients with locked posterior shoulder dislocations for whom significant posterior instability and subluxation persist following closed reduction is described. A specific patient who underwent both arthroscopic posterior stabilization and supplemental advancement of the subscapularis into the reverse Hill-Sachs defect serves as a case example of this technique.