Rotator cable at MR imaging: considerations on morphological aspects and biomechanical role

Area of Science:

• Orthopedic Surgery
• Radiology
• Biomedical Engineering

Background:

• The rotator cable (RC) is an anatomical structure formed by the thickening of the coracohumeral ligament.
• It extends to the infraspinatus tendon and may play a role in maintaining shoulder function, potentially compensating for rotator cuff tears.
• Its thickening with age has been suggested as a factor in preserving shoulder function despite cuff lesions.

Purpose of the Study:

• To evaluate the rotator cable (RC) using magnetic resonance (MR) imaging.
• To investigate the potential biomechanical role of the RC in shoulders affected by rotator cuff lesions.
• To determine if the presence of RC correlates with preserved shoulder function in patients with cuff lesions.

Main Methods:

• Shoulder MR examinations were performed on 104 shoulders from 94 patients (age range 16-79 years) between November 2007 and May 2008.
• The rotator cable was identified and its presence noted.
• Statistical analyses, including Student's t-test and chi-squared test, were used to compare patient age and functional outcomes (Jobe's test) between groups with and without RC, and with different types of rotator cuff lesions.

Main Results:

• The rotator cable was detectable via MR imaging in 62% of the examined shoulders, appearing as a crescent-shaped structure.
• The mean thickness of the RC was measured at 2.8 ± 0.3 mm.
• No statistically significant differences in age were found between patients with and without detectable RC. Furthermore, the presence or absence of RC did not significantly correlate with disability on Jobe's test in patients with partial- or full-thickness supraspinatus tendon lesions.

Conclusions:

• The rotator cable is a discernible structure on MR imaging in over 60% of cases.
• In this study cohort, the rotator cable did not appear to significantly influence shoulder function in patients diagnosed with rotator cuff lesions.