Ultrasound in Adhesive Capsulitis of the Shoulder: The Value of the Coracohumeral Ligament Assessment
Authors: Marcelo Bordalo-Rodrigues, Carlos Homsi, Jader Silva, Xavier Stump
References: Presented at RSNA 2004
PURPOSE Primary adhesive capsulitis of the shoulder is an inflammatory and fibrotic process that mainly affects the rotator interval and the anterior capsule. It has been shown that thickening of the coracohumeral ligament (CHL) is an important pathophysiologic factor in shoulder motion restriction. Since ultrasound (US) is able to depict the CHL as a linear band extending from the coracoid process to the rotator interval, we sought to determine the accessibility of the CHL by US and study the CHL thickness in primary adhesive capsulitis shoulders.
METHOD AND MATERIALS In a prospective study, 494 shoulders were studied in 302 patients (192 women, 110 men, mean age 47 years); 121 asymptomatic shoulders, 12 shoulders with clinical and arthrographic diagnosis of primary adhesive capsulitis and 361 painful shoulders with clinical suspicion of rotator cuff and/or bursal pathology. Longitudinal and axial images of the CHL were obtained and maximal thickness was measured in both planes. Statistical significance for differences in CHL thickness among the three groups of patients was determined by the non-parametric Kruskall-Wallis test. Statistical significance was considered with p values less than .05.
RESULTS The CHL was assessed by ultrasound in 91%(11/12) of the patients with primary adhesive capsulitis, 63%(228/361) of patients with non adhesive capsulitis shoulder pain and in 76%(90/121) of the asymptomatic shoulders. The mean thickness of the CHL in the group of patients with primary adhesive capsulitis was 2.88mm (SD 1.01mm); in the group with non adhesive capsulitis shoulder pain was 1.39mm (SD 0.54mm) and in asymptomatic patients was 1.24mm (SD 0.32mm). The CHL thickness differences between the group of patients with adhesive capsulitis and the other groups was significant (p=.0001).
CONCLUSIONS Ultrasound is a promising method in the evaluation of patients with primary adhesive capsulitis, with emphasis on CHL assessment. Our data indicates that CHL thickening is highly suggestive of primary adhesive capsulitis, differentiating it from other causes of shoulder pain.