Patella Luxation in Dogs: Symptoms, Grading, and Surgical Treatment

What is Patella Luxation?

Patella luxation occurs when the kneecap (patella) dislocates from its normal position in the trochlear groove of the femur. This causes pain, abnormal gait, and lameness. It is extremely common in small breed dogs such as Pomeranians, Chihuahuas, Yorkshire Terriers, Toy Poodles, and Maltese.

Signs Your Dog May Have Patella Luxation

• Intermittent Lameness: Your dog walks normally, then suddenly lifts a hind leg for a few steps before returning to normal.
• Bow-Legged Stance: When viewed from behind, the hind legs appear to curve inward.
• Skipping on Three Legs: Running or hopping using only three legs.
• Reluctance to Jump: Avoiding jumping onto furniture or into cars.
• Abnormal Sitting Posture: Sitting with one leg extended to the side instead of tucked normally.

Grading System (Grade 1-4)

Veterinarians assess severity using a standardized 4-grade system, which determines the treatment approach:

1. Grade 1: The patella can be manually luxated but returns on its own. Dogs rarely show symptoms. Surgery may not be needed, but monitoring is required.
2. Grade 2: The patella luxates spontaneously and sometimes returns on its own. Dogs show intermittent lameness. Surgery is recommended if symptoms are frequent.
3. Grade 3: The patella is permanently luxated but can be manually replaced, only to luxate again. Surgery is strongly recommended.
4. Grade 4: The patella is permanently luxated and cannot be manually replaced. The leg is deformed. Surgery is the only option.

Surgical Treatment Options

Multiple techniques may be combined depending on the severity:

• Trochleoplasty: Deepening the groove in the femur to better seat the kneecap.
• Tibial Tuberosity Transposition: Repositioning the attachment point of the patellar ligament to correct alignment.
• Lateral Imbrication: Tightening the lateral soft tissues to help hold the kneecap in place.

After surgery, most dogs return to normal walking within 4-8 weeks. At Makhamtia Animal Hospital, our veterinary team has over 22 years of experience in patella luxation surgery, with fully equipped, standard operating facilities.