Multiple Subscapularis Tendon Sign: A New Risk Factor for Recurrence After Arthroscopic Anterior Shoulder Instability Surgery

Abstract

Background: Being able to predict recurrence after the treatment of shoulder instability would be helpful in planning the appropriate treatment. Purpose: To define the multiple subscapularis tendon sign (MSTS) as a novel anatomic variant and a possible risk factor for the recurrence of shoulder instability after anterior stabilization and to evaluate it, together with the other risk factors as described in the literature. Study Design: Case-control study; Level of evidence, 3. Methods: A total of 87 patients met the study criteria and underwent arthroscopic stabilization for anterior shoulder instability. The MSTS was evaluated in this study group. Age, sex, hand dominance, number of preoperative shoulder dislocations, history of overhead or contact sports participation, type of labral lesion, number of anchors used in surgery, presence of the drive-through sign, presence of the MSTS, Oxford Shoulder Score results, and the association of these parameters with recurrence were assessed. The mean follow-up time was 81.0 ± 27.9 months (range, 48-139 months). Results: Nine (10.3%) patients experienced recurrent instability. The presence of the MSTS ( P = .009), existence of an anterior labroligamentous periosteal sleeve avulsion (ALPSA) lesion ( P = .04), and history of overhead or contact sports participation ( P = .04) were significant risk factors for recurrence. The recurrence rates were as follows: 30.7% with the MSTS; 40% with the MSTS and an ALPSA lesion; and 75% with the MSTS, an ALPSA lesion, and a history of overhead or contact sports participation. Conclusion: The MSTS is a variation of the anterior shoulder joint capsule. It is a sign of capsular insufficiency or thinning, which may be a risk factor for recurrence after anterior stabilization. Considering the low success rates of anterior capsulolabral repair in patients participating in overhead or contact sports, especially when an ALPSA lesion is present, encountering the MSTS during surgery in this at-risk group may be an indicator for the surgeon to choose the surgical procedure more carefully.

Age, participation in competitive sports, bony lesions, ALPSA lesions, > 1 preoperative dislocations, surgical delay and ISIS score > 3 are risk factors for recurrence following arthroscopic Bankart repair: a systematic review and meta-analysis of 4584 shoulders

“…Seven studies (1,380 shoulders demonstrated a higher recurrence risk in patients with an ISIS > 3 compared to patients with an ISIS ≤ 3 (RR = 3.28; P = 0.0007; I 2 = 77%; supplementary 4, Figure 18); four studies (1136 shoulders) demonstrated a higher recurrence risk in patients with an ISIS > 6 compared to patients with an ISIS ≤ 6 (RR = 4.88; P < 0.00001; I 2 = 71%; supplementary 4, Figure 19). A meta-analysis for MSTS was not feasible, however, Kanatli et al found a higher recurrence rate in patients with the MSTS (31%) compared to patients where the sign was not reported (7%)[ 23 ].…”

“…1. Seven prospective [4, 5, 10, 37, 46, 48, 53] and 22 retrospective studies [1, 3, 6, 7, 14–17, 22–25, 30, 31, 33, 35, 36, 43, 45, 49, 57, 58] were included (Table 1). The included studies comprised a combined sample size of 4584 shoulders (range 51–670) in 4564 patients (supplementary 2).…”

Patients Have a 15% Redislocation Rate After Arthroscopic Bankart Repair With a Knotless Technique

“…An overview of studies with mid- to long-term results after ABR can be found in Table 3 . 4 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 The majority of these studies were undertaken at dedicated sports medicine clinics and university hospitals. Redislocation rate after ABR varies considerably, as do inclusion criteria and patient selection.…”

“… 4 , 5 , 6 , 7 The vast majority of published literature conveys results from dedicated sports medicine centers or large university clinics. 4 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 It is unknown whether these results can be applied to small regional hospitals carrying out this procedure.…”

Failure Rates After Revision Arthroscopic Stabilization for Recurrent Anterior Shoulder Instability Based on Anterior Capsulolabral Complex Conditions

“…Ligamentous laxity or anterior labroligamentous periosteal sleeve avulsion lesions have been reported as soft tissue factors for postoperative recurrence, which are different from anterior capsular tears or fibrotic changes in terms of the pathogenesis and tear location. 11,22 An anterior capsular tear can occur after a traumatic anterior shoulder dislocation, and the anterior capsule loses elasticity after repetitive capsular tears. 4,5 This damage and recurrent dislocation events eventually lead to plastic deformation with scarring and fibrotic changes of the anterior capsule.…”