Medial Patella Luxation (MPL) is a common orthopedic condition in dogs where the kneecap (patella) slips out of its normal position, leading to discomfort and mobility issues. Understanding the causes, symptoms, and treatment options can help pet owners manage this condition effectively.

What is Medial Patella Luxation?

MPL occurs when the patella moves out of its normal groove in the femur, usually toward the inside of the leg. This misalignment can range from mild to severe and may affect one or both knees.

Causes of Medial Patella Luxation

  • Genetic predisposition – Small and toy breeds like Pomeranians, Chihuahuas, and Yorkshire Terriers are more commonly affected.
  • Congenital deformities – Abnormal bone structure can contribute to improper patella alignment.
  • Trauma or injury – Sudden impacts or falls may lead to patella displacement.
  • Muscle imbalances – Weakness in the muscles surrounding the knee joint can cause instability.

Grades of Luxation

  • Grade 1 – Patella can be manually moved out of place but returns on its own.
  • Grade 2 – Patella moves out of place spontaneously but can be repositioned manually.
  • Grade 3 – Patella is out of position most of the time but can be manually repositioned.
  • Grade 4 – Patella is permanently out of position and cannot be manually repositioned.

Signs & Symptoms

  • Intermittent skipping or “hopping” on one leg
  • Sudden lifting of the leg while running or walking
  • Stiffness or difficulty standing after rest
  • Bow-legged stance in severe cases
  • Pain or reluctance to move (especially in higher grades)

Diagnosis

A veterinarian will diagnose MPL through:

  • Physical examination – Assessing knee stability and patella movement.
  • X-rays – Evaluating bone alignment and identifying arthritis.
  • Advanced imaging (CT or MRI) – For complex cases requiring surgical planning.

Treatment Options

1. Non-Surgical Management (For mild cases)

  • Weight management – Maintaining an ideal weight to reduce joint stress.
  • Physical therapy & strengthening exercises – Targeted exercises to improve muscle stability.
  • Joint supplements – Glucosamine and chondroitin to support cartilage health.
  • Pain management – NSAIDs or other pain relievers for inflammation control.

2. Surgical Treatment (For moderate to severe cases)

Surgery is recommended for dogs with frequent pain, reduced mobility, or severe luxation. Common surgical procedures include:

  • Trochlear groove deepening – Creating a deeper groove for the patella to sit securely.
  • Tibial tuberosity transposition (TTT) – Adjusting the position of the bone to realign the patella.
  • Soft tissue reconstruction – Tightening or loosening structures around the knee to stabilize movement.

Post-Treatment Care & Recovery

  • Limited activity – Restricting running and jumping for several weeks post-surgery.
  • Rehabilitation therapy – Guided exercises to strengthen muscles and improve flexibility.
  • Long-term joint care – Continued weight management, joint supplements, and routine check-ups.

Final Thoughts

Medial Patella Luxation can range from a minor inconvenience to a serious mobility issue. Early detection and appropriate management can greatly improve a dog’s comfort and quality of life. If your dog is showing signs of MPL, consult us for a tailored treatment plan.

For more information or to discuss treatment options, contact us today!