Radiological changes in anterior arm muscles after biceps long head tenotomy

Background Although a decrease in pain may be observed after tenotomy, conditions such as muscle cramp, limited elbow flexion, cosmetic deformity (Popeye sign), decreased elbow flexion-supination strength, and persistent pain are also seen, and the exact cause is not fully known.Purpose To evaluate the changes in the short head of the biceps brachii (SHB) tendon thickness and coracobrachialis muscle after tenotomy.Material and Methods In this original article, magnetic resonance imaging (MRI) was performed preoperatively and 6 months postoperatively on 77 patients who underwent biceps brachii long head tenotomy during shoulder arthroscopy and who met the inclusion criteria. Changes in the thickness of the SHB and the coracobrachialis muscle were evaluated. The location where the long head of the biceps brachii (LHB) terminated after tenotomy was also investigated.Results In the 6th postoperative month, we observed a significant increase in both the thickness of the SHB footprint and 2 cm distal to the tendon's origin. In addition, the LHB, which underwent tenotomy, was distracted on average 24.2 mm distally. However, no changes were observed in the thickness of the coracobrachialis muscle during the same period.Conclusion In this study, we demonstrated prospectively increased thickness of the SHB tendon and no increase in thickness in the coracobrachialis muscle on postoperative MRI.