Glenoid Bone Loss in Recurrent Shoulder Instability After Arthroscopic Bankart Repair: A Systematic Review

No Difference in Outcome Scores or Persistent Instability After Latarjet Procedure for Anterior Instability in Patients With Shoulder Hyperlaxity Versus Those Without Hyperlaxity

BACKGROUND

The prevalence of hyperlaxity in patients with shoulder instability is high, and its management is challenging. Shoulder hyperlaxity denotes a redundant anterior capsule with an elongated or weak glenohumeral ligament that may be associated with worse functional outcomes after procedures for instability. The functional outcomes and postoperative recurrence after a Latarjet procedure for recurrent instability in shoulders with hyperlaxity versus those without hyperlaxity has not been studied.

QUESTIONS/PURPOSES

(1) What are the differences in functional outcomes (Rowe score and shoulder subjective value [SSV]) after a Latarjet procedure for unidirectional anterior instability in shoulder hyperlaxity versus no hyperlaxity, and what proportion of shoulders achieve the patient acceptable symptom state (PASS) in both groups? (2) What is the difference in the proportion of patients who experienced a recurrence after a Latarjet procedure for unidirectional anterior instability in shoulder hyperlaxity versus no hyperlaxity? (3) What are the differences in radiologic outcomes after a Latarjet procedure for unidirectional anterior instability in shoulder hyperlaxity versus no hyperlaxity?

METHODS

Between January 2014 and January 2022, one surgeon performed the Latarjet procedure for anterior shoulder instability in 155 patients. During that time, he performed the Latarjet for all patients with recurrent instability, with or without bone loss and with or without shoulder hyperlaxity. Of those who fit the prespecified inclusion criteria, 37% (48 of 131) had shoulder hyperlaxity (defined as external rotation [elbow adducted] ≥ 85° in the opposite normal shoulder) and 63% (83 of 131) had no hyperlaxity. A total of 90% (43 of 48) of the patients with shoulder hyperlaxity and 87% (72 of 83) of patients without hyperlaxity had a minimum follow-up time of 2 years and were evaluated for the first two study questions by comparing functional outcomes (SSV, Rowe scores, ROM) and the proportion of patients who experienced recurrent instability after a Latarjet procedure. We also compared the hyperlaxity group with a subgroup of 32 patients with no hyperlaxity who had ≥ 15% glenoid loss (defined as the "critical defect, no hyperlaxity" group). In addition, 84% (36 of 43) of patients in the hyperlaxity group and 81% (58 of 72) in the no hyperlaxity group had CT scans at a median (range) 3 years (1 to 7) after surgery, and this subset of patients was analyzed for radiologic outcomes. The PASS was defined as an SSV of 82.5%, per an earlier study. Recurrent instability after the procedure was defined as any overt instability (dislocation, subluxation) or anterior apprehension noted in the postoperative period. Subluxation was evaluated clinically based on the patient's history of a subjective instability event or a dislocation of the glenohumeral joint that could be self-reduced. The patients in the hyperlaxity group were younger (mean ± SD age 23 ± 4 years) and had a smaller preoperative glenoid defect (4% ± 7%) than those in the no hyperlaxity group (age 28 ± 7 years, p < 0.001; glenoid defect 11% ± 9%, p < 0.001) and those in the critical defect, no hyperlaxity group (age 27 ± 8 years, p = 0.01; glenoid defect 19% ± 6%, p < 0.001). A priori sample size calculation showed that at a power of 90% and an alpha value of 0.05, a total of 18 patients were needed in each group to detect a difference in SSV of 12 ± 11 points.

RESULTS

The hyperlaxity group did not differ from the no hyperlaxity group in terms of SSV (median [IQR] 85 [80 to 95] versus 90 [80 to 95], difference of medians -5; p = 0.17), Rowe score (median [IQR] 95 [90 to 100] versus 98 [88 to 100], difference of medians -3; p = 0.61), or Duplay-Walch score (median [IQR] 90 [86 to 100] versus 90 [80 to 100], difference of medians 0; p = 0.73). We found no difference between the hyperlaxity and the no hyperlaxity group in terms of the proportion of patients who achieved the PASS (56% [24 of 43] versus 71% [51 of 72], OR 0.5 [95% CI 0.23 to 1.14]; p = 0.10). The hyperlaxity group did not differ from the no hyperlaxity group in the proportion of patients who experienced postoperative instability (12% [5 of 43] versus 11% [8 of 72], OR 1.1 [95% CI 0.32 to 3.45]; p = 0.93). We found no difference between the hyperlaxity and the no hyperlaxity group in terms of bony healing (97% [35 of 36] versus 98% [57 of 58], OR 0.6 [95% CI 0.04 to 10.13]; p > 0.99). We found no difference between the hyperlaxity and the no hyperlaxity group in the proportion of patients who had major graft resorption at the superior screw level in the sagittal section (86% [31 of 36] versus 90% [52 of 58], OR 0.7 [95% CI 0.20 to 2.54]; p = 0.74), minor graft resorption at the inferior screw level in the sagittal section (100% [36 of 36] versus 97% [56 of 58], OR 3.2 [95% CI 0.15 to 69.2]; p = 0.45), and acceptable mediolateral graft positioning at the superior screw level (75% [27 of 36] versus 79% [46 of 58], OR 0.8 [95% CI 0.29 to 2.10]; p = 0.62) and the inferior screw level (75% [27 of 36] versus 86% [50 of 58], OR 0.5 [95% CI 0.17 to 1.39]; p = 0.18).

CONCLUSION

The Latarjet procedure for unidirectional shoulder instability does not result in inferior functional outcomes or higher postoperative recurrence in patients with preexisting shoulder hyperlaxity compared with patients without hyperlaxity. Therefore, our findings suggest that shoulder hyperlaxity may not necessarily be an exclusion criterion for performing the Latarjet procedure. Future studies may need to compare the functional outcomes and complications after the Latarjet procedure with those of capsular plication procedures in patients with hyperlaxity and shoulder instability.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Assessment of Primary Stability and Micromotion of Different Fixation Techniques for Scapular Spine Bone Blocks for the Reconstruction of Critical Bone Loss of the Anterior Glenoid-A Biomechanical Study

Anteroinferior shoulder dislocations require surgical intervention when related to critical glenoid bone loss. Scapular spine bone blocks have emerged as a promising alternative to traditional bone augmentation techniques. However, limited data exist on their biomechanical stability when using different suture-based fixation techniques. This study aimed to evaluate primary stability and micromotion after glenoid augmentation using a scapular spine bone block. A total of 31 fresh-frozen human shoulder specimens underwent bone block augmentation. The specimens were randomized into three groups: double-screw fixation (DSF), single-suture bone block cerclage (SSBBC), and double-suture bone block cerclage (DSBBC). Biomechanical testing was conducted using cyclic loading (5000 cycles at 1 Hz) and micromotion was analyzed using an optical 3D measurement system. Statistical analysis showed that medial irreversible displacement was significantly greater in the SSBBC group compared to DSF (p = 0.0386), and no significant differences were found in anterior or inferior irreversible displacements. A significant difference was noted in posterior reversible displacement (p = 0.0035), while no differences were found in inferior or medial reversible displacements. Between DSF and DSBBC, no significant differences were found in irreversible or reversible displacements in any direction. DSBBC provided stability comparable to DSF while offering a viable metal-free alternative. In contrast, SSBBC displayed inferior biomechanical properties, raising concerns about its clinical reliability.

The Coraco-Gleno-Scapular line: A simple tool for assessing glenoid bone defects

BACKGROUND

The treatment decisions for shoulder instability often necessitate surgical intervention, with glenoid bone loss being a key factor. Currently, various techniques exist to identify glenoid bone loss, each with its own advantages and disadvantages. This study introduces the Coraco-Gleno-Scapular (CGS) line as a tool for assessing critical glenoid bone defects. The objective is to define the CGS line and evaluate its utility in guiding clinical decisions regarding bone loss, proposing that defects extending posterior to this line indicate critical bone involvement requiring surgical intervention.

METHODS

The study analyzed 50 normal right shoulders from individuals aged 18-40 years. Using 3D en face views of the glenoid, the CGS line was defined from the anteroinferior base of the coracoid process, crossing the anterior glenoid, to the anteroinferior pole of the scapula. The best-fit circle area method and the glenoid index linear method were used to calculate the percentage of the bone area located anterior to the CGS line.

RESULTS

The best fit circle area method revealed a mean glenoid surface area anterior to the CGS line of 22.19%, while the glenoid index linear method indicated a mean area of 27.2% anterior to the CGS line. Of the 50 shoulders, 14 had a glenoid surface area <20% anterior to the CGS line using the best-fit circle method, with no cases below 17.5%, while 36 individuals had a glenoid surface area >20%.

CONCLUSION

The Coraco-Gleno-Scapular line is a reliable and simple tool for assessing glenoid bone loss, providing valuable guidance in managing shoulder instability. Its ease of use makes it a promising candidate for standard application in clinical practice.

LEVEL OF EVIDENCE

Prospective observational study, Level III.

Arthroscopic Bankart repair augmented with glenoid bone dry allograft

Background

The recurrence rate of shoulder instability after arthroscopic isolated Bankart repair is up to 25% at long term, especially in case of bipolar bone loss. Bony augmentation with free bone dry allograft would be an option to reconstruct a glenoid subcritical bone defect and to minimize the failure rate.

Methods

This case series included patients with anterior shoulder instability treated by arthroscopic free bone dry allograft (Supercrit, BIOBank, Lieusaint, Ile-de-France, France), fixed with a cortical button as an augmentation of Bankart repair and reviewed with a minimum follow-up of 2 years. Clinical assessment was based on active range of motion, shoulder apprehension test, as well as Walch-Duplay Score, Rowe Score, and Subjective Shoulder Value. Radiological evaluation was based on postoperative and last follow-up computed tomography scan to assess bone block positioning, glenoid enlargement, allograft healing, and/or resorption.

Results

Five patients were included with a mean follow-up of 50 months (range 44-56). None of the patients reported a recurrence, but apprehension test was positive in one. Mean Walch-Duplay Score, Rowe Score, and Subjective Shoulder Value were 88 points (70-11), 93 points (75-100), and 89% (80-95), respectively. No surgical complications were recorded. The mean preoperative anterior glenoid bone loss was 13.8% (7-19). At last follow-up, graft resorption was observed in all patients, reaching 100% of the initial volume in 4 cases.

Conclusion

This study showed satisfactory clinical results of Bankart repair augmented with dry bone allograft in the treatment of anterior shoulder instability with glenoid subcritical bone loss. However, anatomical results were disappointing, with graft resorption that raises the question of going ahead with such a procedure.

Biomechanical Analysis Reveals Shoulder Instability With Bipolar Bone Loss Is Best Treated With Dynamic Anterior Stabilization for On-Track Lesions and With Remplissage for Off-Track Lesions

PURPOSE

To compare the biomechanical effects of augmenting Bankart repair (BR) with either remplissage or dynamic anterior stabilization (DAS) in the treatment of anterior shoulder instability with on-track or off-track bipolar bone loss.

METHODS

Eight fresh-frozen cadaveric shoulders were tested at 60° of glenohumeral abduction in the intact, injury, and repair conditions. Injury conditions included 15% glenoid bone loss with an on-track or off-track Hill-Sachs lesion as previously recommended. Repair conditions included isolated BR, BR with remplissage, and BR with DAS (long head of biceps transfer). The glenohumeral stability was assessed by measuring the anterior translation under 0, 10, 20, 30, 40, 50 N load and maximum load without causing instability at mid-range (60°) and end-range (90°) external rotation (ER). Maximum range of motion (ROM) was measured by applying a 2.2-N·m torque in passive ER and internal rotation.

RESULTS

Isolated BR failed to restore native glenohumeral stability in both on-track and off-track bipolar bone loss models. Both remplissage and DAS significantly decreased the anterior instability in the bipolar bone loss models, showing better restoration than the isolated BR. In the on-track lesions, DAS successfully restored native glenohumeral stability and mobility, whereas remplissage significantly decreased anterior translation without load (-2.12 ± 1.07 mm at 90° ER, P = .003; -1.98 ± 1.23 mm at 60° ER, P = .015). In the off-track lesions, remplissage restored native glenohumeral stability but led to significant ROM limitation (-8.6° ± 2.3° for internal rotation, P < .001; -13.9° ± 6.2° for ER, P = .003), whereas DAS failed to restore native stability at 90° ER regarding the increased anterior translation under 50 N (4.10 ± 1.53 mm, P < .001) and decreased maximum load (-13.8 ± 9.2 N, P = .021).

CONCLUSIONS

At time-zero, both remplissage and DAS significantly reduced residual anterior instability compared with isolated BR in the bipolar bone loss models and restored the native glenohumeral stability under most translational loads. However, remplissage could decrease the anterior translation without load for on-track lesions and may restrict ROM for off-track lesions, whereas DAS failed to restore native stability under high translational loads for off-track lesions.

CLINICAL RELEVANCE

DAS could be recommended to treat on-track bipolar bone loss with less biomechanical adverse effects, whereas remplissage might be the preferred procedure to address off-track bipolar bone loss for better stability.