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Pet Health Guidance

Patellar Luxation

A structured information page for mobility and joint health guidance.

Veterinary Guidance

What Is Patellar Luxation in Pets?

Patellar luxation, also known as a slipped or dislocated kneecap, is a condition where the kneecap (patella) slips out of its normal position in the femoral groove. It is one of the most common orthopaedic conditions in dogs and cats, particularly affecting small breeds.

Normally, the patella slides up and down within the femoral groove as the knee bends. When it slips out, it causes joint instability, pain, and difficulty walking. Small breed dogs are 12 times more likely to develop this condition compared to large breed dogs.

Grading System (Grades 1 to 4)

Grade Characteristics Clinical Presentation
Grade 1 Kneecap can be manually pushed out but returns spontaneously. Usually no obvious symptoms or pain.
Grade 2 Luxates frequently; may require manual reduction. Intermittent "leg lifting" or skipping when walking.
Grade 3 Kneecap is out of position most of the time. Persistent lameness; abnormal knee bending.
Grade 4 Permanently displaced and cannot be reduced. Severe pain and mobility impairment.

Warning Signs

What You Observe

  • Sudden lifting of one leg while walking.
  • "Skipping" or hopping gait.
  • Reluctance to jump or climb stairs.
  • Clicking or popping sounds from the knee.

Common Causes

  • Congenital/Hereditary (Shallow groove).
  • Abnormal bone angles (Femur/Tibia).
  • Traumatic injury (Falls/Accidents).
  • Obesity (Additional joint stress).

Treatment Options

Conservative Management

For mild cases (Grade 1-2). Aims to strengthen muscles and reduce inflammation.

  • Weight Control: Reducing stress on the joint.
  • Physical Therapy: Underwater treadmill and massage.
  • Supplements: Glucosamine and Omega-3.

Surgical Correction

Recommended for Grade 2-4 to restore stability and prevent arthritis.

  • Trochleoplasty: Deepening the femoral groove.
  • Tibial Transposition: Realigning the ligament.
  • Recovery: Gradual activity return over 1-3 months.

Don't Delay Treatment

Patellar luxation is an irreversible condition. Without intervention, it leads to chronic pain and degenerative joint disease. Early diagnosis is key to maintaining your pet's quality of life.