Recurrence in traumatic anterior shoulder dislocations increases the prevalence of Hill–Sachs and Bankart lesions: a systematic review and meta-analysis

Purpose The extent of shoulder instability and the indication for surgery may be determined by the prevalence or size of associated lesions. However, a varying prevalence is reported and the actual values are therefore unclear. In addition, it is unclear whether these lesions are present after the first dislocation and whether or not these lesions increase in size after recurrence. The aim of this systematic review was (1) to determine the prevalence of lesions associated with traumatic anterior shoulder dislocations, (2) to determine if the prevalence is higher following recurrent dislocations compared to first-time dislocations and (3) to determine if the prevalence is higher following complete dislocations compared to subluxations. Methods PubMed, EMBASE, Cochrane and Web of Science were searched. Studies examining shoulders after traumatic anterior dislocations during arthroscopy or with MRI/MRA or CT published after 1999 were included. A total of 22 studies (1920 shoulders) were included. Results The proportion of Hill–Sachs and Bankart lesions was higher in recurrent dislocations (85%; 66%) compared to first-time dislocations (71%; 59%) and this was statistically significant (P < 0.01; P = 0.05). No significant difference between recurrent and first-time dislocations was observed for SLAP lesions, rotator-cuff tears, bony Bankart lesions, HAGL lesions and ALPSA lesions. The proportion of Hill–Sachs lesions was significantly higher in complete dislocations (82%) compared to subluxations (54%; P < 0.01). Conclusion Higher proportions of Hill–Sachs and Bankart were observed in recurrent dislocations compared to first-time dislocations. No difference was observed for bony Bankart, HAGL, SLAP, rotator-cuff tear and ALPSA. Especially when a Hill–Sachs or Bankart is present after first-time dislocation, early surgical stabilization may need to be considered as other lesions may not be expected after recurrence and to limit lesion growth. However, results should be interpreted with caution due to substantial heterogeneity and large variance. Level of evidence IV.

An assessment of SLAP type 5 lesions using proton density oblique sagittal imaging in magnetic resonance arthrography

Background Bankart lesions accompany superior labrum anteroposterior (SLAP) lesions; these are called SLAP type 5. Purpose To compare SLAP type 5 lesions using routine magnetic resonance arthrography (MRA) and thin-slice oblique sagittal proton density (PDW) sequences and correlation operation results. Material and Methods In total, 181 patients were admitted with shoulder instability. The study was completed with 44 patients. The presence or absence of isolated Bankart and SLAP type 5 lesions in routine MRA and PDW oblique sagittal images were evaluated separately. Absence of rupture scored 0 points, suspected ruptures scored 1 point, and apparent ruptures scored 2 points. The two scores were compared with the shoulder arthroscopy findings. Results According to the findings in the shoulder arthroscopy, 40 patients had Bankart lesions and 17 patients had accompanying SLAP type 5 lesions. To detect a Bankart lesion, there was no significant difference between routine MRA sequences and PDW oblique sagittal images ( P = 0.061). Routine MRA sensitivity was 95%, specificity 25%, positive predictive value (PPV) 92%, negative predictive value (NPV) 33%, while for PDW oblique sagittal images, sensitivity was 75%, specificity 100%, PPV 100%, and NPV 28.5%. In 8/17 type 5 SLAP lesions, routine MRA detected sensitivity 47%, specificity 92.6%, PPV 80%, and NPV 73.5%; in 14/17 SLAP type 5 lesions, PDW oblique sagittal images detected sensitivity 82%, specificity 100%, PPV 100%, and NPV 90% ( P = 0.015). Conclusion The PDW oblique sagittal images may play a significant role in assessing the anterior and superior extent of the tears.

Chondral Damage After Arthroscopic Repair Techniques for Acute Bony Bankart Lesions: A Biomechanical Study

Background: Bony Bankart lesions can be encountered during treatment of shoulder instability. Current arthroscopic bony Bankart repair techniques involve intra-articular suture placement, but the effect of these repair techniques on the integrity of the humeral head articular surface warrants further investigation. Purpose: To quantify the degree of humeral head articular cartilage damage secondary to current arthroscopic bony Bankart repair techniques in a cadaveric model. Study Design: Controlled laboratory study. Methods: Testing was performed in 13 matched pairs of cadaveric glenoids with simulated bony Bankart fractures, with a defect width of 25% of the glenoid diameter. Half of the fractures were repaired with a double-row technique, while the contralateral glenoids were repaired with a single-row technique. Samples were subjected to 20,000 cycles of internal-external rotation across a 90° arc at 2 Hz after a compressive load of 750 N, or 90% body weight (whichever was less) was applied to simulate wear. Cartilage defects on the humeral head were quantified through a custom MATLAB script. Mean cartilage cutout differences were analyzed by the Wilcoxon rank-sum test. Results: Both single- and double-row repairs showed macroscopic damage. The histomorphometric analysis demonstrated that the double-row technique resulted in a significantly ( P = .036) more chondral damage (mean, 57,489.1 µm2; SD, 61,262.2 µm2) than the single-row repair (mean, 28,763.5 µm2; SD, 24,4990.2 µm2). Conclusion: Both single-row and double-row arthroscopic bony Bankart fixation techniques resulted in damage to the humeral head articular cartilage in the concavity-compression model utilized in this study. The double-row fixation technique resulted in a significantly increased cutout to the humeral head cartilage after simulated wear in this cadaveric model. Clinical Relevance: This study provides data demonstrating that placement of intra-articular suture during arthroscopic bony Bankart repair techniques may harm the humeral head cartilage. While the double-row repair of bony Bankart lesions is more stable, it results in increased cartilage damage. These findings suggest that alternative, cartilage-sparing arthroscopic techniques for bony Bankart repair should be investigated.

Arthroscopic Bankart Repair and Open Bristow Procedure in the Treatment of Anterior Shoulder Instability With Osseous Glenoid Lesions in Collision Athletes

Background: Traumatic anterior shoulder instability in collision sports athletes often involves osseous glenoid lesions, which make surgical treatment challenging. High redislocation rates have been seen in collision sports athletes treated using arthroscopic Bankart repair. Purpose: To investigate the effectiveness of a combined arthroscopic Bankart repair and open Bristow procedure for the treatment of traumatic anterior shoulder instability in collision sports athletes, with a focus on osseous glenoid lesions. Study Design: Case series; Level of evidence, 4. Methods: We reviewed 149 shoulders in 141 competitive collision sports athletes (mean ± standard deviation age, 20.1 ± 4.1 years; 8 bilateral cases) who underwent a combined arthroscopic Bankart repair and open Bristow procedure with minimum 2 years of follow-up. Osseous Bankart lesions were arthroscopically reduced and fixed using a coracoid graft. Results: Clinical outcomes as indicated by mean Rowe score improved significantly from 50.0 preoperatively to 98.9 postoperatively ( P < .001) at a median follow-up of 3.4 years (range, 2.5-7 years). There were 2 recurrent dislocations (1.3%), both of which had nonunion of the transferred coracoid. Osseous Bankart lesions were observed in 85 shoulders, and osseous glenoid lesions ≥10% of the diameter of the nonoperative side were found in 58 shoulders, including 24 off-track cases. Clinical outcomes were not significantly different between patients with a glenoid defect ≥10% and <10%. Nonunion of the transferred coracoid was observed in 16 shoulders (10.7%), which had inferior Rowe scores; however, we could not define any risk factors for nonunion, including patient characteristics or bone morphology. Postoperative computed tomography performed in 29 patients >1 year after surgery showed successful repair of the osseous glenoid lesions, with a restored glenoid articular surface in all cases. Significant pre- to postoperative increases were seen in glenoid diameter (mean, 13.1% [95% CI, 9.9%-16.3%]; P < .001) and area (mean, 10.6% [95% CI, 8.5%-12.7%]; P < .001). Conclusion: A combined arthroscopic Bankart repair and open Bristow procedure improved bone morphology and was a reliable surgical method for treating collision sports athletes with traumatic anterior shoulder instability involving osseous glenoid lesions.

A Biomechanical, Cadaveric Evaluation of Single- Versus Double-Row Repair Techniques on Stability of Bony Bankart Lesions

Background: Previous studies comparing stability between single- and double-row arthroscopic bony Bankart repair techniques focused only on the measurements of tensile forces on the bony fragment without re-creating a more physiologic testing environment. Purpose: To compare dynamic stability and displacement between single- and double-row arthroscopic repair techniques for acute bony Bankart lesions in a concavity-compression cadaveric model simulating physiologic conditions. Study Design: Controlled laboratory study. Methods: Testing was performed on 13 matched pairs of cadaveric glenoids with simulated bony Bankart fractures with a defect width of 25% of the inferior glenoid diameter. Half of the fractures were repaired with a double-row technique, and the contralateral glenoids were repaired with a single-row technique. To determine dynamic biomechanical stability and ultimate step-off of the repairs, a 150-N load and 2000 cycles of internal-external rotation at 1 Hz were applied to specimens to simulate early rehabilitation. Toggle was quantified throughout cycling with a coordinate measuring machine. Three-dimensional spatial measurements were calculated. After cyclic loading, the fracture displacement was measured. Results: The bony Bankart fragment–glenoid initial step-off was found to be significantly greater ( P < .001) for the single-row technique (mean, 896 µm; SD, 282 µm) compared with the double-row technique (mean, 436 µm; SD, 313 µm). The motion toggle was found to be significantly greater ( P = .017) for the single-row technique (mean, 994 µm; SD, 711 µm) compared with the double-row technique (mean, 408 µm; SD, 384 µm). The ultimate interface displacement was found to be significantly greater ( P = .029) for the single-row technique (mean, 1265 µm; SD, 606 µm) compared with the double-row technique (mean, 795 µm; SD, 398 µm). Conclusion: Using a concavity-compression glenohumeral cadaveric model, we found that the double-row arthroscopic fixation technique for bony Bankart repair resulted in superior stability and decreased displacement during simulated rehabilitation when compared with the single-row repair technique. Clinical Relevance: The findings from this study may help guide surgical decision-making by demonstrating superior biomechanical properties (improved initial step-off, motion toggle, and interface displacement) of the double-row bony Bankart repair technique when compared with single-row fixation. The double-row repair construct demonstrated increased stability of the bony Bankart fragment, which may improve bony Bankart healing.