Ever noticed your pint-sized pooch taking an impromptu hop or running on three legs, only to miraculously revert to a four-legged dash? You might have witnessed the curious case of the medial luxating patella, often dubbed a "trick knee." Join us as we unravel this intriguing condition that frequently affects toy breed dogs, exploring its causes, severity grades, and the surgical solutions that can set your furry friend back on the right track.
A Misstep in the Groove
Imagine a scenario: your furry companion is frolicking around when suddenly, their kneecap (patella) decides to take a detour. Instead of gliding smoothly within its groove, the patella veers off track and heads medially toward the opposite leg. This phenomenon is the hallmark of a medial luxating patella, causing the knee to remain bent and impeding proper extension. Luckily, some dogs manage to pop the patella back into place, seemingly unfazed. But for others, surgical correction is the key to regaining normalcy.
Grading the Wobble
Medial patellar luxations come in varying degrees of severity:
- Grade I: The patella can be manually moved out of place but readily returns to its natural position when released.
- Grade II: The patella occasionally ventures out of its groove, leading to intermittent lameness. While surgical intervention might not be immediate, factors like frequency and duration of lameness play a role. Surgery can also prevent progression to Grade III by averting bone ridge wear.
- Grade III: The patella remains out of place but can be coaxed back manually, though it won't stay put. This stage brings persistent lameness, crouching, and rear weakness, resulting in a bow-legged appearance.
- Grade IV: The patella remains perpetually dislocated, defying all manipulation attempts. Dogs in this category find it challenging to extend their knees, often walking with perpetually bent legs. Here, the intricate bone rotation accompanying the luxation can hinder surgical correction.
Why Correct the Kneecap Conundrum?
While a luxating patella might not initially seem painful, it can trigger a series of structural changes over time. Alterations in weight-bearing stress eventually impact the hips and long bones and trigger the onset of arthritis. The severity of these changes depends on the grade of the luxation and its duration. As time goes on, legs can even twist outward as muscles turn inward, creating a bow-legged stance. Arthritis gradually sets in, causing discomfort.
Surgical Symphony
For Grade I cases, surgical repair might not be necessary, with weight management and anti-inflammatory medication potentially sufficing. However, Grade III and IV cases generally warrant surgery.
Various surgical procedures can address the issue:
- Lateral Imbrication: This technique involves adjusting the joint capsule to prevent patellar slipping.
- Trochlear Modification: By deepening the groove where the patella rests, this procedure ensures the patella stays in place.
- Tibial Crest Transposition: If leg bone rotation has occurred, repositioning the crest can straighten the leg.
- The Ridgestop Implant: A novel approach, this involves adding a small curved plate to prevent patellar displacement.
Single or Double Trouble?
Whether to repair one or both knees simultaneously depends on factors like the dog's age and the surgeon's philosophy. Consultation with a veterinary specialist can guide this decision-making process.
Nurturing the Healing Journey
Post-surgery, care involves weeks of confinement, with variations based on the procedure performed. Easy walking is recommended, with physical therapy potentially aiding dogs who take longer to use the treated leg comfortably.
Unveiling the mystery of the medial luxating patella showcases the intricate interplay between anatomy and surgical ingenuity. With the right approach, your canine companion can dance their way back to a comfortable, four-legged rhythm.
Don't have a vet in your area yet? We can help you find a local veterinarian.
If you have more questions, the GeniusVets Telehealth platform will give you unlimited access to text and/or video calls with board-certified veterinarians! To learn more click here.