Patellar luxation in small breed dogs: Symptoms and treatment

Patellar luxation is a common orthopedic condition that affects small breed dogs more frequently than larger ones. Breeds such as Yorkshire Terriers, Pomeranians, Chihuahuas, and Miniature Poodles are particularly predisposed to this issue due to their anatomical structure and genetic tendencies.

The condition occurs when the patella, or kneecap, moves out of its normal groove in the femur. This displacement can be either medial (toward the inside of the leg), which is more common, or lateral (toward the outside), and it leads to instability of the knee joint, discomfort, and eventually long-term damage to the joint if not addressed properly.

Owners often first notice a skipping gait or intermittent lameness in their dogs. The dog may suddenly pick up one of its hind legs while walking or running, hold it up for a few steps, and then resume normal use as if nothing happened.

This behavior is due to the kneecap slipping out of place and then spontaneously returning to its normal position. Over time, especially in more severe cases, this can become more frequent and progress to constant lameness, reluctance to play or jump, and muscle atrophy in the affected limb. In chronic cases, the altered biomechanics can lead to arthritis and significant discomfort for the animal.

The severity of patellar luxation is often graded on a scale from I to IV, with Grade I involving occasional luxation that resolves spontaneously and Grade IV involving permanent displacement that cannot be manually reduced. Diagnosis is usually made through a combination of physical examination and radiographs, although advanced imaging such as CT scans may be helpful in surgical planning.

Treatment depends on the severity of the condition and the level of pain or dysfunction experienced by the dog. Mild cases might be managed conservatively with weight control, physical therapy, and anti-inflammatory medications, but moderate to severe cases often require surgical correction. The goal of surgery is to realign the patella and restore proper biomechanics of the stifle joint.

Common procedures include deepening the femoral groove, realigning the patellar tendon, and tightening or releasing the surrounding soft tissues.

Postoperative recovery involves strict rest, often crate confinement, and a gradual return to activity over several weeks, sometimes supported by physical therapy to regain strength and joint function.

The prognosis after surgery is generally very good, especially when the procedure is performed by a skilled veterinary orthopedic surgeon and followed by appropriate rehabilitation.

Early diagnosis and intervention are key to preventing long-term joint degeneration and ensuring the best possible outcome for the affected pet. Understanding the signs of patellar luxation and seeking veterinary guidance promptly can make a significant difference in a small dog’s quality of life.

References:

1. Piermattei DL, Flo GL, DeCamp CE. Brinker, Piermattei and Flo's Handbook of Small Animal Orthopedics and Fracture Repair. 5th ed. Elsevier; 2015.
   

2. Hayes AG, Boudrieau RJ. “Patellar luxation in dogs: pathogenesis and surgical management.” Veterinary Clinics of North America: Small Animal Practice. 1997;27(4):961–986.
   

About the autor

Felipe Garofallo is a veterinarian in Brazil, specialized in orthopedic and neurosurgical care for dogs and cats.

He is also the founder of Ortho for Pets – Veterinary Orthopedics and Specialties.