Biceps Tendon Injury ( biceps tenosynovitis)

Dogs with a biceps tendon injury have an intermittent of progressive lameness in one or both front legs that may be worse following exercise. Some dogs can exhibit muscle atrophy of the muscles surrounding the shoulder joint. A painful response can be elicited with deep palpation of the biceps tendon in most dogs. Pain develops as the inflamed tendon and tendon sheath courses over a rough irregular surface of the biceps tendon groove near the shoulder joint. 

Most dogs with a biceps tendon injury are middle-aged to older medium to large breed dogs. Injuries to the biceps tendon can occur in athletic or sedentary dogs. 

Diagnosis is based on physical findings of pain localized to the shoulder and accentuation of pain with deep palpation of the tendon. Radiographs (X-rays) may demonstrate mineralization of the tendon or biceps tendon groove and osteophyte formation in other areas of the shoulder joint. An arthrocentesis (sample of joint fluid) may reveal evidence of degenerative joint disease. Diagnosis of biceps tendon injuries can be difficult and frustrating as clinical signs and radiographic changes can be subtle. A MRI evaluation of the biceps tendon is more sensitive at detecting subtle injuries to the tendon and chronic changes within the biceps tendon groove. Arthroscopic evaluation of the biceps tendon is also a sensitive means of detecting a biceps tendon injury. Arthroscopy has the additional advantage of being able to treat the condition at the time of diagnosis, whereas the MRI evaluation would require a separate anesthetic episode. 

Treatment options for biceps tenosynovitis medical management and surgical management techniques. Initially, most dogs with a biceps tendon injury can be addressed with intra-articular injection of corticosteroids and rest for 4-6 weeks. The steroid injection may provide a durable relief from pain cause by the tendon injury by relieving the inflammation associated with the injury. Recurrence of lameness occurs in approximately 50% of patients with a biceps tendon injury. If the response to the first injection was good a second injection can be considered. Overall the response rate to corticosteroid injection and rest is approximately 70%. Of the patients that fail initial conservative attempts to manage the condition or patients that exhibit severe chronic changes on MRI or radiographic studies, surgical management can be considered. Currently arthroscopic evaluation and treatment of tendon injuries is the treatment of choice. Arthroscopy allows less invasive and more effective evaluation of the tendon, cartilage surface and rotor cuff tendons of the shoulder. Whether surgical correction is performed arthroscopically or by an open technique the premise of surgery is to relocate the tendon away from the inciting cause of repetitive injury. Outcomes are good to excellent in patients that are not responding to medical management.