Tendinopathy means “disease of a tendon.” In this case, it is the disease of the tendon of the supraspinatus muscle. The supraspinatus muscle is responsible for extension of the shoulder joint. Injury to the tendon of the supraspinatus muscle causes inflammation. Tearing of the tendon fibers and the resulting inflammation can lead to mineralization and calcification of the tendon. The calcium deposits are a source of pain and lameness.
Supraspinatus tendinopathy is most commonly seen in active adult, large breed dogs.
The most common clinical sign of supraspinatus tendinopathy is lameness that gradually worsens throughout the day, with minimal or moderate activity. The degree of lameness depends on the severity of the lesion. The dog will also experience pain in the shoulder, made worse by flexing and internally rotating the affected leg.
Diagnosis is based on history, clinical signs, and a thorough physical exam. Mineralization of the supraspinatus tendon is often visible on radiographs or using ultrasound. Arthroscopy is the most efficient way to thoroughly examine the joint. It is important to note however, that the calcifications may not be the sole cause of the lameness, and other orthopedic conditions must be ruled out.
Like many other orthopedic injuries, especially of the shoulder, supraspinatus tendinopathy is often a result of overuse or a repeated strain injury. As the damaged tendon heals, the body’s response is to lay down calcium deposits, causing lameness and pain.
Acute cases can be medically managed with rest, NSAIDs, and physical therapy, but treatment may need to be repeated. For dogs who do not respond to conservative treatment, surgery may be warranted.
Longitudinal incisions are made in the supraspinatus tendon, and the calcium deposits are removed.
Dogs that participate in strenuous activity, such as working, hunting, or agility dogs should be properly conditioned and “warmed up” prior to exercise. If your dog sustains an injury during exercise, it is important to seek veterinary treatment immediately. Physical therapy and anti-inflammatories can help limit the damage caused by inflammation. Additionally, weight management is key in preventing orthopedic conditions.
Provided this calcification was the cause of the lameness and no other shoulder condition exist, the prognosis is excellent. The dogs usually improve within 2 to 4 weeks and usually totally recover within 6 to 8 weeks.