Medial Patella Luxation (MPL) may require surgery

Medial Patella Luxation (MPL)

Our Commitment to Excellence:

At Sandringham Veterinary Hospital, we are dedicated to providing the highest quality care without the high costs often associated with referral hospitals.

Patellar Luxation Correction: Restoring Comfort and Mobility

Patellar luxation is the dislocation of the patella bone in the knee, akin to our knee cap. When a healthy knee bends, the kneecap slides smoothly within a groove in the thighbone. However, when the kneecap dislocates from this groove, we call it Medial Patella Luxation (MPL), or a dislocating kneecap. MPL can cause pain, limping, and hindered mobility for your beloved pet.

Understanding MPL Severity:

MPL can affect one or both knees and ranges in severity from grade 1 to grade 4:

  • Grade 1: The kneecap is loose but generally stays in place. It may dislocate when forced but easily returns.
  • Grade 2: The kneecap occasionally dislocates but often returns by itself, with symptoms varying from mild to moderate.
  • Grade 3: The kneecap is permanently dislocated but can be manually repositioned by a vet before slipping again.
  • Grade 4: The kneecap is permanently dislocated and cannot be repositioned.

Causes of MPL:

MPL is primarily a genetic issue, often due to the abnormal alignment of the patella tendon, typically toward the inside of the leg. This condition is common in young, small breed dogs, including Poodles, Pomeranians, Shih Tzus, Maltese, and Chihuahuas, but can occasionally occur in larger breeds.

Identifying MPL Symptoms:

Your pet may show signs of MPL such as:

  • Skipping or lifting a leg during walks
  • Favoring one leg
  • Stiffness in one or both legs

In some cases, the kneecap may slip back into place, and your pet might adapt to kick it back when needed. However, the condition can worsen over time, leading to increased pain, inflammation, and the risk of early arthritis.

Treatment for MPL:

  • In cases of grade 1 or mild grade 2 luxation, conservative management with anti-inflammatory medication and controlled exercise on a leash can be effective. However, most grade 2 cases progress and may require surgical correction to prevent worsening symptoms.
  • Surgical correction involves repositioning the kneecap in three steps: adjusting the attachment point in the bone, deepening the kneecap groove, and tightening loose ligaments. This procedure is typically required for grade 3 or 4 luxations and pets experiencing discomfort.

Recovery Process:

  • Surgery at our clinic and includes an overnight hospital stay, post-operative rechecks, and medications.
  • Post-surgery recovery spans 6 weeks, during which your pet’s activity will be restricted. Weight bearing on the affected leg is not expected in the first two weeks.
  • Prognosis after surgical correction is generally good for grades 1, 2, or 3 luxations, with about 90% of cases achieving an excellent functional outcome.