Ultrasound demonstration of distal triceps tendon tears.

PURPOSE: Rupture of the distal triceps tendon is an uncommon injury that may be unrecognized on clinical examination. The purpose of the study is to describe the role of US in distal triceps tendon tears evaluation.

MATERIALS AND METHODS: IRB approval was obtained and patients gave written informed consent. Of 77 consecutive US examinations of the elbow obtained over a five-year period, eight patients with correlative MR and surgery available were identified having partial or complete distal triceps tendon tear.

RESULTS: N = 4 complete tears of the triceps tendon and n = 4 partial tears of the distal triceps involving the lateral/superficial head were identified. Patients with partial tear had a history of a single traumatic event that determined a sudden eccentric contraction of the triceps muscle against resistance. US demonstrated on axial and longitudinal planes a partial tear of the triceps brachii tendon that resulted in a fusiform swelling and retraction of the lateral/superficial head in four patients. It was possible to identify the normal insertion of the medial head of the triceps moving the transducer medially. MR and surgical findings were concordant with US findings in every patient.

CONCLUSION: Ultrasound is able to differentiate complete from partial triceps tendon tears. US has the potential to identify isolated lesions of the lateral/superficial head of the triceps with an intact medial head.