Lameness related to the stifle (knee) can be the result of many different conditions. Some of the more common causes are patella luxation, cruciate ligament disease and traumatic arthritis.  Other causes of stifle related lameness include trauma related fractures and luxations, infections, tumors and immune- mediated disease.

Patella luxation (dislocation of the knee cap)

This condition may be the result of a congenital defect or trauma.  The patella usually slips medially and produces intermittent non-painful lameness. Most respond to conservative therapy. Occasionally patella luxation can produce significant lameness, pain and even locking the leg in extension. Surgery is recommended in these cases.

Cruciate ligament injuries (tearing or stretching this ligament inside the knee)

Many times the ligament is injured during vigorous play. Diabetes, obesity and patella luxation are predisposing factors. Partial tears produce less clinical signs and heal more quickly than complete rupture of the ligament. The most common clinical sign is acute non-weight bearing lameness with joint swelling. Conservative therapy is appropriate initially for most patients.   If the cat does not improve during this period surgery will be recommended.

Traumatic arthritis (inflammation of the joint)

This can result from an awkward fall, fights with other cats and many other types of feline accidents. The least severe form of injury is a joint sprain in which there is stretching and tearing of the joint capsule and ligaments. Most sprains will heal with conservative therapy.

Diagnosis of these conditions is made by palpation of the joint and radiographs. Sometimes a sedative is needed to allow the relaxation needed to fully examine the joint.

Conservative therapy:

1.     Weight optimization

2.     Confinement

3.     Pain control

a.      Aspirin 81 mg tablet- ½ tablet every 48 – 72 hours- It may produce gastric irritation and should be given with food. It is useful for mild  pain.

b.  Buprenorphine –Good for acute pain. It is most useful the first 72 hours after injury. It is a liquid that is absorbed through the mucosa of the mouth.

c. Meloxicam – a non-steroidal anti-inflammatory that may be given with Buprenorphine for severe pain- but cannot be given with aspirin. It is a potent anti-inflammatory medication and excellent for orthopedic injuries. It cannot be given if the patient has any kidney disease. In addition kidney values must be monitored after the first week of therapy and then every three months if therapy is continued.

Most cats respond well to conservative therapy but if your cat does not respond, he/she will be referred to an orthopedic specialist for evaluation and surgery if indicated. Our goal for every patient is a pain free recovery to normal activity levels.