Recurrent Instability After Arthroscopic Bankart Repair in Patients With Hyperlaxity and Near-Track Lesions

Risk factors for recurrence following arthroscopic Bankart repair: a systematic review

BACKGROUND

Recurrent instability remains a major source of morbidity following arthroscopic Bankart repair. Many risk factors and predictive tools have been described, but there remains a lack of consensus surrounding individual risk factors and their contribution to outcomes. The purpose of this study is to systematically review the literature to identify and quantify risk factors for recurrence following arthroscopic Bankart repair.

METHODS

A literature search was performed using the PubMed/MEDLINE databases based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Studies were included if they evaluated risk factors for recurrent instability following arthroscopic Bankart repair.

RESULTS

Overall, 111 studies were included in the analysis, including a total of 19,307 patients and 2750 episodes of recurrent instability with 45 risk factors described. Age at operation was reported by 60 studies, with 35 finding increased risk at younger ages. Meta-analysis showed a 2-fold recurrence rate of 27.0% (171 of 634) for patients <20 years old compared with 13.3% (197 of 1485) for older patients (P < .001). Seventeen studies completed multivariable analysis, 13 of which were significant (odds ratio 1.3-14.0). Glenoid bone loss was evaluated by 39 studies, with 20 finding an increased risk. Multivariable analysis in 9 studies found odds ratios ranging from 0.7 to 35.1; 6 were significant. Off-track Hill-Sachs lesions were evaluated in 21 studies (13 significant), with 3 of 4 studies that conducted multivariable analysis finding a significant association with odds ratio of 2.9-8.9 of recurrence. The number of anchors used in repair was reported by 25 studies, with 4 finding increased risk with fewer anchors. Pooled analysis demonstrated a 25.0% (29 of 156) risk of recurrence with 2 anchors, compared with 18.1% (89 of 491) with 3 or more anchors (P = .06). Other frequently described risk factors included glenohumeral joint hyperlaxity (46% of studies reporting a significant association), number of preoperative dislocations (31%), contact sport participation (20%), competitive sport participation (46%), patient sex (7%), and concomitant superior labral anterior-posterior tear (0%).

CONCLUSION

Younger age, glenoid bone loss, and off-track Hill-Sachs lesions are established risk factors for recurrence following arthroscopic Bankart repair. Other commonly reported risk factors included contact and competitive sports participation, number of fixation devices, and patient sex.

Lateral femoral impaction fractures during an ACL tear extend posteriorly on the weight-bearing area of the tibiofemoral joint

PURPOSE

Posterior elongation of the physiological terminal sulcus (TS) due to lateral femoral condyle impaction fracture (LFC-IF) after an anterior cruciate ligament (ACL) tear could potentially decrease the weight-bearing area of the tibiofemoral joint, decrease the tension on lateral meniscus and cause flattening of the LFC which would influence rotational knee motion and cause anisometry of the lateral and anterolateral stabilizers. Therefore, the purpose of the study was to assess if the LFC-IF elongates the physiological TS posteriorly.

METHODS

One hundred patients magnetic resonance images (MRIs) (75 males, 25 females, mean age 32.2 years, SD = 8.2) were included with a 1:1 ratio between the full-thickness ACL tear group and the control group (patients with knee MRI performed due to other reasons, with no tear of ACL on MRI and negative clinical tests). Two independent raters evaluated the sagittal T1-weighted preselected MRI scans. The principal measurement of interest was the distance from the intersection of the Blumensaat line with subchondral bone to the posterior border of the TS/LFC-IF.

RESULTS

The median distance from the Blumensaat line to the posterior border of the TS/LFC-IF was significantly higher in the ACL tear group: 14.3 mm, interquartile range (IQR) = 11.6-16.4 mm versus control group: 12.8 mm, IQR = 9.0-15.0 mm, p = 0.038. Intrarater and inter-rater reliabilities were >0.90.

CONCLUSION

LFC-IF after full-thickness ACL tear significantly elongates the physiological TS in the posterior direction.

LEVEL OF EVIDENCE

Level III.

Defining Critical Humeral Bone Loss: Inferior Craniocaudal Hill-Sachs Extension as Predictor of Recurrent Instability After Primary Arthroscopic Bankart Repair

BACKGROUND

The glenoid track concept for shoulder instability primarily describes the medial-lateral relationship between a Hill-Sachs lesion and the glenoid. However, the Hill-Sachs position in the craniocaudal dimension has not been thoroughly studied.

HYPOTHESIS

Hill-Sachs lesions with greater inferior extension are associated with increased risk of recurrent instability after primary arthroscopic Bankart repair.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

The authors performed a retrospective analysis of patients with on-track Hill-Sachs lesions who underwent primary arthroscopic Bankart repair (without remplissage) between 2007 and 2019 and had a minimum 2-year follow-up. Recurrent instability was defined as recurrent dislocation or subluxation after the index procedure. The craniocaudal position of the Hill-Sachs lesion was measured against the midhumeral axis on sagittal magnetic resonance imaging (MRI) using either a Hill-Sachs bisecting line through the humeral head center (sagittal midpoint angle [SMA], a measure of Hill-Sachs craniocaudal position) or a line tangent to the inferior Hill-Sachs edge (lower-edge angle [LEA], a measure of Hill-Sachs caudal extension). Univariate and multivariate regression were used to determine the predictive value of both SMA and LEA for recurrent instability.

RESULTS

In total, 176 patients were included with a mean age of 20.6 years, mean follow-up of 5.9 years, and contact sport participation of 69.3%. Of these patients, 42 (23.9%) experienced recurrent instability (30 dislocations, 12 subluxations) at a mean time of 1.7 years after surgery. Recurrent instability was found to be significantly associated with LEA >90° (ie, Hill-Sachs lesions extending below the humeral head equator), with an OR of 3.29 (P = .022). SMA predicted recurrent instability to a lesser degree (OR, 2.22; P = .052). Post hoc evaluation demonstrated that LEA >90° predicted recurrent dislocations (subset of recurrent instability) with an OR of 4.80 (P = .003). LEA and SMA were found to be collinear with Hill-Sachs interval and distance to dislocation, suggesting that greater LEA and SMA proportionally reflect lesion severity in both the craniocaudal and medial-lateral dimensions.

CONCLUSION

Inferior extension of an otherwise on-track Hill-Sachs lesion is a highly predictive risk factor for recurrent instability after primary arthroscopic Bankart repair. Evaluation of Hill-Sachs extension below the humeral equator (inferior equatorial extension) on sagittal MRI is a clinically facile screening tool for higher-risk lesions with subcritical glenoid bone loss. This threshold for critical humeral bone loss may inform surgical stratification for procedures such as remplissage or other approaches for at-risk on-track lesions.