Progression of Erosive Changes of Glenoid Rim After Arthroscopic Bankart Repair

Arthroscopic Bankart repair with peeling osteotomy of the anterior glenoid rim preserves glenoid morphology

BACKGROUND

A decrease in the glenoid size after arthroscopic Bankart repair (ABR) was common in shoulders without osseous fragments compared with those with osseous fragments. For cases of chronic recurrent traumatic anterior glenohumeral instability without osseous fragments, we have performed ABR with peeling osteotomy of the anterior glenoid rim (ABRPO) to make an intentional osseous Bankart lesion. The aim of this study was to compare the glenoid morphology after ABRPO with it after simple ABR.

METHODS

The medical records of patients who underwent arthroscopic stabilization for chronic recurrent traumatic anterior glenohumeral instability were retrospectively reviewed. Patients with an osseous fragment, with revision surgery and without complete data were excluded. Patients were assigned to 1 of 2 groups: Group A, ABR without peeling osteotomy procedure or Group B, with ABRPO procedure. Computed tomography was performed preoperatively and 1 year after surgery. The size of the glenoid bone loss was investigated by the assumed circle method. The following formula was used to calculate the decreased size of the glenoid: (Δ) = (postoperative size of the glenoid bone loss) - (preoperative size of the glenoid bone loss). The size of the glenoid 1 year after surgery was assessed to determine if it had decreased (Δ > 0%) or not decreased (Δ ≤ 0%) relative to the preoperative size.

RESULTS

This study evaluated 39 shoulders divided into 2 groups: 27 shoulders in Group A and 12 shoulders in Group B. In Group A, postoperative glenoid bone loss was significantly greater than preoperative glenoid bone loss (7.8 ± 6.2 vs. 5.5 ± 5.3, respectively, P = .02). In Group B, postoperative glenoid bone loss was significantly lower than preoperative glenoid bone loss (5.6 ± 5.4 vs. 8.7 ± 4.0, respectively, P = .02). The P value for the interaction of group (A or B) × time (preoperative or postoperative) was 0.001. The decreased size of the glenoid was significantly larger in Group A than in Group B (2.1 ± 4.2 vs. -3.1 ± 4.5, respectively, P = .001). The rate of shoulders in which the size of the glenoid decreased 1 year after surgery relative to the preoperative size was significantly higher in Group A than in Group B (63% [17/27] vs. 25% [3/2], respectively, P = .04).

CONCLUSIONS

The study showed that ABRPO preserved the glenoid size better than simple ABR without a peeling osteotomy procedure.

New bone formation after arthroscopic Bankart repair for unstable shoulders with an erosion-type glenoid defect

BACKGROUND

The purpose of the present study was to retrospectively evaluate new bone formation after arthroscopic Bankart repair (ABR) and the influence of new bone formation on recurrence in shoulders with an erosion-type glenoid defect.

METHODS

We analyzed data on shoulders with an erosion-type glenoid defect. Participants were patients who underwent computed tomography to evaluate new bone formation after ABR performed from 2004 to 2021 and were followed for a minimum of 2 years. We investigated the factors influencing new bone formation, in particular the presence of an intraoperative bone fragment, and the influence of new bone formation and its size on postoperative recurrence.

RESULTS

A total of 100 shoulders were included. The mean glenoid defect size was 10.1% ± 6.3% (range, 1.2%-31.5%). New bone formed postoperatively in 15 shoulders (15.0%) and was seen in significantly more shoulders with an intraoperative bone fragment (11 of 18, 61.1%) than in those without a fragment (4 of 82, 4.9%; P < .001). Recurrence occurred in 22 shoulders (22.0%), and the rate of recurrence was not different between shoulders with new bone formation (3 of 15, 20.0%) and without new bone formation (19 of 85, 22.4%; P = .999). Among the 15 shoulders with new bone formation, the size of the new bone fragments relative to glenoid width was <5% in 2 shoulders, 5%-<7.5% in 8 shoulders, 7.5%-<10% in 3 shoulders, and ≥10% in 2 shoulders; in all 3 shoulders with postoperative recurrence, the relative size was <7.5%.

CONCLUSIONS

Even in shoulders with an erosion-type glenoid defect, new bone may form after ABR, especially in shoulders with an intraoperative bone fragment. However, new bone formation does not decrease the rate of postoperative recurrence.

Anterior glenoid rim erosion in the early stage after arthroscopic Bankart repair affects postoperative recurrence

Background

Recent studies reported that anterior glenoid rim erosion can occur in the early period after arthroscopic Bankart repair (ABR) for traumatic anterior shoulder instability. However, it is unknown whether such erosion is a risk factor for postoperative recurrence. This study evaluated risk factors for postoperative recurrence after ABR, specifically aiming to elucidate whether reduction of postoperative glenoid width due to anterior glenoid rim erosion is one of such factors.

Methods

A total of 220 shoulders that underwent ABR alone between 2013 and 2020 were retrospectively investigated. Patient age at surgery, whether the patient was a collision/contact athlete, anchor placement, preoperative glenoid bone defect (%), localization of the Hill-Sachs lesion, and change of glenoid width (%) in the 6 months after surgery were investigated for their statistical relation to recurrence by univariate and multiple logistic regression analysis.

Results

Postoperative recurrence occurred in 32 of 220 shoulders (14.5%). In univariate analysis, being a collision/contact athlete was the only variable with a significant effect on recurrence (odds ratio [OR], 2.555; 95% confidence interval [CI], 1.123-5.814; P = .03). Change of glenoid width reduction was larger in those with recurrence than without recurrence, but the difference was not statistically significant (-7.0 ± 6.6% vs. -5.0 ± 9.3%; P = .14). However, in multivariate logistic analysis, preoperative glenoid bone defect (%) (adjusted unit OR, 1.076; 95% CI, 1.018-1.137; P = .010) and postoperative change of glenoid width (%) (adjusted unit OR, 0.946; 95% CI, 0.900-0.994; P = .028) had a significant influence on postoperative recurrence.

Conclusion

Glenoid width reduction due to anterior glenoid rim erosion after ABR is a risk factor for recurrence.

Early Treatment of Shoulder Pathology Is Necessary but Not Enough Is Being Performed

Delayed treatment of shoulder instability results in bone loss requiring more-complicated surgery, in turn resulting in less-optimal outcomes. Similarly, delayed treatment of repairable rotator cuff tears results in irreparable tears requiring more-complicated surgery and resulting in less-optimal outcomes. Delayed treatment of shoulder pathology is a problem. Solutions include education and research investigation.

On-the-Edge Anchor Placement May Be Protective Against Glenoid Rim Erosion After Arthroscopic Bankart Repair Compared to On-the-Face Anchor Placement

PURPOSE

This retrospective study aimed to compare the effects of 2 different anchoring placements on glenoid rim erosion after arthroscopic Bankart repair (ABR).

METHODS

Shoulders that underwent ABR from January 2013 to July 2020 were divided into 2 groups according to anchor placement (on-the-face, group F; on-the-edge, group E). We retrospectively calculated the percent change of glenoid width (Δ) on the first postoperative computed tomography scan (CT; performed within 6 months) and second postoperative CT (performed at 6 to 12 months) relative to the width on the preoperative CT and compared percent changes between the 2 groups. Also, we investigated the influence of preoperative glenoid structures (normal, erosion, bony Bankart) and the postoperative recurrence rate.

RESULTS

We examined 225 shoulders in 214 patients (group F, n = 151; group E, n = 74). At first CT, anchoring placement was significantly associated with postoperative decrease of glenoid width (group F, -7.6% ± 7.9%; group E, -0.1% ± 9.7%; P < .0001). The difference between groups F and E was significant in shoulders with a preoperative glenoid defect (bony Bankart, -6.6% ± 8.8% vs 2.5% ± 11.2%, respectively; P < .0001; erosion, -6.6% ± 6.2% vs -2.6% ± 5.3%, respectively; P = .03). In 112 shoulders, CT was performed twice; Δ was -6.9% ± 7.3% in group F (n = 64) and -1.7% ± 10.1% in group E (n = 48; P = .005) at the first CT and -3.2% ± 10.0% and 1.0% ± 10.6% (P = .10), respectively, at the second CT, indicating recovery of glenoid width in both groups. The postoperative recurrence rate in patients with at least 2 years' follow-up was 14.7% in group F and 14.6% in group E.

CONCLUSIONS

In the early stage after ABR, on-the-edge glenoid anchor placement was associated with less glenoid rim erosion than on-the-face anchor placement.

LEVEL OF EVIDENCE

Level III, retrospective comparative trial.

Editorial Commentary: Anchor Position Affects Glenoid Resorption Rates After Arthroscopic Bankart Repair: Shoulder Stabilization Surgery Is a Game of Millimeters

The technical nuances of arthroscopic Bankart repair cannot be overstated. Previous literature has identified a number of risk factors for failure of arthroscopic stabilization procedures, and the implications of glenoid bone loss is widely recognized as a critical driver of postoperative outcomes. However, other technical considerations (inadequate number of suture anchors, improper position of suture anchors) have been acknowledged as risk factors for the failure of arthroscopic stabilization procedures. More recently, concerns have been raised regarding the observed rates of glenoid bone resorption following arthroscopic Bankart repair, which theoretically may predispose higher rates of clinical failure. Furthermore, certain techniques for placing anchors on the glenoid during arthroscopic Bankart repair may accelerate these resorptive changes. Precise measures of poststabilization surgery glenoid resorption coupled with comprehensive assessments of clinical outcomes are required to determine the optimal technique for anchor insertion during arthroscopic Bankart repair.

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.

Glenoid bone resorption after Bankart repair: finite element analysis of postoperative stress distribution of the glenoid

BACKGROUND

There are various modifications of the Bankart repair, and postoperative changes to the glenoid morphology after the repair are reported. Among the various procedures performed, a decrease in the lateral glenoid diameter might be related to the surgery that involves removal of the articular cartilage and repair of the labrum-anterior inferior glenohumeral ligament complex on the glenoid surface. This is in contrast to cases without significant bony Bankart lesions that are not on the edge of the glenoid. Thus, this study aimed to compare glenoid rim stress after Bankart repair using 2 methods of finite element analysis: a method of removing the anteroinferior cartilage and repairing the glenohumeral ligament complex on the glenoid and a method of preserving the cartilage and repairing the glenohumeral ligament complex on the glenoid edge.

METHODS

Five preoperative computed tomography scans of patients with traumatic anterior instability who underwent arthroscopic Bankart repair were used. Two models simulating different surgical procedures were created as follows: in model G, a 5-mm-thick cartilage on the glenoid rim was removed between 2 and 7 o'clock, and the glenohumeral ligament complex was repaired on the medial edge of the glenoid bone where the cartilage was removed. In model E, the cartilage on the glenoid rim was not removed, and the glenohumeral ligament complex was repaired on the glenoid edge. The load stresses on the anteroinferior area of the glenoid after Bankart repair with models G and E were measured using finite element analysis.

RESULTS

The stress on the glenoid at 3-4 o'clock was 3.16 MPa in model G and 6.42 MPa in model E (P = .043). The stress at 4-5 o'clock was 1.68 MPa in model G and 4.53 MPa in model E (P = .043). The stress at 5-6 o'clock was 2.26 MPa in model G and 3.93 MPa in model E (P = .043).

CONCLUSION

Significantly lower load stresses were observed at the anteroinferior rim of the glenoid in model G than in model E.

Editorial Commentary: Should We Worry About Progressive Glenoid Bone Loss After Arthroscopic Bankart Repair?

One of the key factors in shoulder stabilization surgery is how much glenoid bone loss is present. Too much glenoid bone loss, or the combination of glenoid bone loss combined with a humeral side Hill-Sachs deformity, can lead to an "off-track" lesion and significantly greater risk of recurrence. If the potential surgical solution for instability leads to greater glenoid bone loss, we could create more problems for our patients.