Mineralization of the Supraspinatus Tendon: Clinical Observations in Seven Dogs

SummaryMineral-like densities in the supraspinatus tendon were determined to have different clinical significance according to their location. Those identified radiographically and surgically, near the biceps tendon sheath reflecting a deep location in the supraspinatus tendon, caused chronic and acute lameness in five large breed dogs. Pain in the shoulder and biceps tendon was elicited on examination in acute cases whilst chronic cases were painfree. Systemic and local anti-inflammatory treatment failed to improve any of the cases. Surgical removal was curative with slight lameness after exercise observed in some dogs during the longterm follow-up. Recurrence of lesions were not seen radiologically. It is suggested that mineralizations, located deep in the supraspinatus tendon, cause secondary tenosynovitis of the biceps brachii through mechanical irritation.Mineralizations found radiographically distant to the biceps tendon sheath in five cases reflecting a superficial location in the supraspinatus were determined not to be a primary cause of lameness.Similarities in the pathomechanism, aetiopathogenesis and clinical significance of mineralizations in the supraspinatus tendon in dogs and humans were noted.Mineralizations located deep in the supraspinatus tendon near the biceps tendon sheath caused lameness in large breed dogs. Diagnosis was established through physical examination, radiography, and surgical exploration of the lesion. Systemic steroidal and non-steroidal therapy and local steroid injection into the intertubercular groove failed to resolve any of the cases but surgical curettage of the mineralization resulted in clinical improvement. A secondary mechanical tenosynovitis of the biceps brachii as the cause of lameness, is suggested.Mineralizations located superficially in the supraspinatus tendon were found not to be a primary cause of lameness.