Medial humeral epicondylitis (MHE) is caused by tearing and calcification of the flexor tendons at their attachment site on the inside of the elbow joint. Cats with MHE can present with/without concomitant arthritis and other changes. MHE has been associated with subluxation or dislocation of the elbow joints, which may cause arthritis over time. Bone spurs may develop in this region, resulting in impingement of the ulnar nerve which sits near these muscles. This can cause discomfort and weakness. The cause of MHE is unknown but may be related to trauma or repetitive overuse.
Cats with medial humeral epicondylitis can present with a varying degree of front limb lameness. Other signs of MHE include atrophy of the affected front leg (especially at the lower leg), swelling, and pain with bending and straightening of the elbow. Cats with MHE may also limit their own activity level, such as decreasing their jumping/landing activities, negotiating stairs, running, and playing.
MHE is often diagnosed by radiographs, which can show subtle rounding and slight irregularity of the medial humeral condyle. However, radiographs may be completely normal in the early stages of the disease. In severe cases, large semicircular mineralized structures may be seen at the back and inside of the elbow joint.
For mild cases of MHE, conservative treatment may be successful. Conservative treatment focuses on reducing pain and inflammation at the medial elbow, increasing blood flow to encourage soft tissue repair and tissue remodeling, and gentle exercise to build up strength of the front limb.
For more severe cases, surgery may be needed to relieve symptoms. After surgery, cats are placed in a flexion splint that keeps their wrist in a flexed position to avoid overstretching the repaired muscle. Each week, gradually more range of motion is allowed. Typically cats are in the splint for 3-4 weeks. In the beginning of rehab, we will focus on decreasing pain and inflammation, relaxing muscles, and improving range of motion as tolerated. Once out of the splint, we will begin gentle isometric exercises and slowly progress to harder exercises to rebuild strength.
