Shoulder
Osteochondrosis (OC) / Osteochondritis Dissecans (OCD)
This condition occurs when cartilage does not transition to bone as part of the normal growth and development of bones and joints. The primary location is on the head of the humerus (the ball part of the shoulder joint). It causes mild to severe forelimb lameness in dogs that are 6 to 12 months of age. Both shoulder joints are often affected, but one is usually more lame and painful than the other. A key diagnostic test is pain with extension of the shoulder joint in a young dog. Confirmation of the diagnosis is a radiograph with a characteristic lesion seen. Surgical removal of the cartilage flap generally results in significant improvement. This can be performed with and incision and small opening in the shoulder joint, or by arthroscopy
Shoulder OCD lesion. Note the flattening of the head of the humerus, with mineralized fragment located over the flattened area.
Arthroscopic image of a shoulder OCD lesion.
The scapular part of the shoulder joint is here.
The cartilage fragment is in the grasper.
The bone under the flap is here.
Normal cartilage of the humerus is here.
Biceps Tenosynovitis
The biceps muscle crosses both the shoulder and elbow joints. Sometimes it becomes inflamed, stretched, and in advanced cases, partially or completely torn. Middle aged to older active dogs are most frequently affected. Lameness may be intermittently mild to severe, continuous non weight-bearing lameness. The test that is usually performed is to simultaneously flex the shoulder and extend the elbow to put maximum tension on the muscle-tendon unit; this results in pain. Palpation directly over the upper part of the biceps tendon also creates pain. A diagnostic test to more completely characterize the condition is ultrasound of the tendon and muscle. Treatment options include conservative management with rest and nonsteroidal anti-inflammatory medications, extracorporeal shockwave treatment, therapeutic laser, therapeutic ultrasound, biologic therapy with stem cells or platelet rich plasma, and surgery.
Partial tear of the biceps brachii tendon from its origin on the supraglenoid tubercle.
Supraspinatus Tendinpathy
This muscle runs along the front of the scapula and inserts on the upper part of the humerus (greater tubercle). The tendon insertion of this muscle may become inflamed, stretched, or torn. Chronic cases often have some calcification of the tendon insertion. Diagnostic ultrasound can more completely characterize the problem. Dogs generally have a mild to moderate forelimb lameness that progressively worsens if not treated. Pain may also be present when the area is palpated. Treatment options include conservative management with rest and nonsteroidal anti-inflammatory medications, extracorporeal shockwave treatment, therapeutic laser, therapeutic ultrasound, biologic therapy with stem cells or platelet rich plasma, and surgery.
Infraspinatus Contracture
This muscle runs along the back of the scapula and inserts on the upper part of the humerus below the supraspinatus muscle. The tendon/muscle may become damaged with fibrosis. Initially, owners may remember some degree of lameness, but as the muscle and tendon undergo fibrosis, the front limb assumes the characteristic position with the elbow rotated in to the chest, and the foot and forelimb externally rotated. Diagnostic ultrasound can more completely characterize the problem. Dogs generally have a mild to moderate forelimb lameness with inability to completely extend the shoulder joint. Treatment is generally very effective, and consists of completely releasing the scar tissue with rehabilitation after surgery to help prevent recurrence.
