Summary

Biceps sheath fluid may not be an important finding to consider when determining treatment for individuals with symptomatic tears isolated to the supraspinatus tendon.

Abstract

Introduction

Biceps sheath fluid is often found in patients with rotator cuff tears. Because the supraspinatus and subscapularis tendons are connected to the entrance of the long head biceps (LHB) tendon into the glenohumeral joint, when these tendons are torn, the LHB tendon becomes unstable. This can result in LHB tendonitis and accumulation of fluid in the biceps sheath, causing shoulder pain and loss of function. However, the influence of biceps sheath fluid on patient-reported outcomes (PROs) and factors associated with the presence of fluid in the biceps sheath are unclear. Therefore, this study aims to identify factors associated with biceps sheath fluid and their impact on PROs in individuals with isolated supraspinatus tendon tears.

Methods

A total of 106 individuals (mean age, 60.2 ± 9.9 years; 50 females) who had a symptomatic isolated tear more than 50% partial- or full-thickness of the supraspinatus tendon confirmed by ultrasound were prospectively enrolled. All individuals participated in a personalized 12-week exercise therapy program. Fluid in the biceps tendon sheath was evaluated as more than 2 mm of fluid thickness, which was measured at the longest distance from the sheath to the margin of the LHB tendon in the transverse plane of the acquired ultrasound images at the time of enrollment. The individuals were divided into fluid, or no fluid groups based on the presence of biceps sheath fluid. The factors associated with the presence of biceps sheath fluid that were explored included age, height, BMI, hand dominance, onset of shoulder pain, history of smoking, working status (current or retired), symptom duration (>3 months or <3 months), tear size (anterior-posterior direction) and thickness (partial or full), and the Western Ontario Rotator Cuff Index (WORC) score at the time of enrollment. To identify factors associated with biceps sheath fluid, variables were compared between groups using the chi-square tests for categorical variables and the independent-samples t-test or Mann-Whitney U tests for continuous variables. Additionally, multivariate logistic regression analysis with a backwards stepwise technique was performed using variables with P < 0.10 during the univariate analysis. Statistical significance was set at P < 0.05.

Results

More than 2 mm of fluid thickness in the biceps sheath was found in 35 (33.0%) individuals at baseline. The fluid group was significantly older than non-fluid group (65.1 ± 8.5 years vs 57.8 ± 9.8 years, p < 0.001). Other variables including the WORC score were not significantly associated with biceps sheath fluid at baseline (Table 1). The multivariate analysis including age, sex, and hand dominance, showed that only age was significantly associated with fluid in the biceps sheath at baseline (p < 0.001).

Conclusion

Biceps sheath fluid in isolated supraspinatus tear was not associated with patient reported symptoms or function as measured by the WORC. Thus, biceps sheath fluid may not be an important finding to consider when determining treatment for individuals with symptomatic tears isolated to the supraspinatus tendon.