What is a patellar test in dogs?

What is a patellar test in dogs? - briefly

The patellar test in dogs is a diagnostic procedure used to assess the stability and proper functioning of the patella (kneecap) within the dog's hind leg. This test involves gently manipulating the knee joint to determine if the patella can be dislocated or if it slides out of its normal position, which may indicate issues like patellar luxation.

What is a patellar test in dogs? - in detail

The patellar test, also known as the patellar luxation test or the cranial drawer test, is a critical diagnostic procedure used by veterinarians to evaluate the stability of the patella (kneecap) in dogs. This test is particularly important because patellar luxation, where the patella dislocates or moves out of its normal position, is a common orthopedic issue among dogs, especially small and toy breeds.

During the patellar test, the veterinarian will carefully examine the dog's hind legs, focusing on the stifle joint (the equivalent of the human knee joint). The dog is typically positioned in a way that allows for full visualization and palpation of the joint. In most cases, the dog may be standing or lying down with its leg extended slightly to facilitate access to the patella.

The veterinarian will then gently manipulate the patella by applying pressure to it and attempting to displace it either medially (towards the inside) or laterally (towards the outside). The goal is to assess the integrity of the ligaments and other supporting structures that maintain the patella in its normal position within the trochlear groove.

If the patella moves easily or completely out of the groove with minimal effort, it indicates a degree of luxation. Veterinarians classify patellar luxation into four grades based on the severity and frequency of dislocation:

  1. Grade 1: The patella can be manually displaced but returns to its normal position without any intervention.
  2. Grade 2: The patella dislocates with manual pressure and may return spontaneously, but there is some degree of laxity in the supporting structures.
  3. Grade 3: The patella consistently dislocates with minimal or no manual effort and does not return to its normal position without intervention.
  4. Grade 4: The patella is permanently luxated and cannot be manually replaced within the trochlear groove.

The results of the patellar test help veterinarians determine the appropriate course of treatment, which may range from conservative management with physical therapy and weight control to surgical intervention in severe cases. Early diagnosis and timely treatment are essential to prevent further damage to the joint and associated structures, ensuring the dog's long-term comfort and mobility.