A luxating patella occurs when the kneecap moves out of its natural position. Medial patella luxation (MPL) is a common problem in dogs. While it affects any breed and size, toy breeds such as Yorkshire Terriers, miniature Poodles, and Chihuahuas are over-represented.

MPL can be the result of an injury but is usually a developmental problem with a bone deformity in the tibia and/or femur. This leads to an inward pull of the quadriceps muscles encompassing the patella (kneecap). With a significant pull, the patella dislocates (luxates) inwardly (medial).

Severity varies and is classified on a grading scale (I-IV). We recommend surgical treatment for dogs showing signs of the patella luxation or with a grade III or grade IV luxation.

Veterinary Surgery for MPL Procedure

Surgical management may require a variety of procedures. Most importantly the insertion of the patellar tendon should be realigned so the patella is pulled in the proper direction (tibial tuberosity transposition). Often, the trochlear groove of the femur, where the patella normally resides, has become flattened and a new groove needs to be created (tracheloplasty).

In addition to these bone modification procedures, soft tissue around the knee may be released or tightened as needed to allow the kneecap to ride smoothly in the groove.

Your dog’s recovery from knee surgery

After surgery, pets must be confined for 6-8 weeks to allow for proper healing. Short leash walks and controlled physical therapy exercises are appropriate. Implants usually stay for the rest of the animal’s lifetime, however, can be removed if they migrate or cause irritation.

Complications are rare but include premature migration of implants and reluxation of the patella. The board certified surgeons at WestVet have extensive training and experience with MPL and knee procedures.

Please see your family veterinarian for a referral for a consultation with a WestVet surgeon. If you have any questions regarding your dog’s knee surgery, contact us directly at 208.375.1600.