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Tampa Bay K9 Rehabilitation Center

Luxating Patella

Luxating patella, or trick knee, is a condition in which the patella (kneecap) dislocates or moves out of place. Causes for this may include some form of blunt trauma, or possibly a congenital defect.

Luxating patella is a common orthopedic condition that affects many dogs. Many pet owners have had to deal with the effects of the condition on their pets. A luxating patella occurs when the kneecap moves from its normal position. While the condition most often affects small breeds like Yorkshire terriers, Pomeranians, and Chihuahuas, it can also affect larger dogs. The condition can be quite painful, but fortunately, it is treatable.


Some causes of canine luxating patella include genetics where skeletal deformities are involved and poor nutrition. Dogs that are overweight risk developing the condition due to excessive pressure on the knee joint. Too much exercise for certain dog breeds can also cause stress on the joints, especially with dog breeds that grow too fast.


The symptoms of luxating patella in canines will depend on the severity of the condition. Some common symptoms include mild-to-severe pain, a popping sound coming from the knee, and abnormal gait during movement. The animal will try to avoid placing weight on the affected knee or leg.  Many dogs will be non-weight bearing for a few steps, then extend the leg—which releases the patellar ligament.  In grade I & II luxations, the patella often will pop back into its normal position and the dog becomes instantly sound.


The severity of the problem is divided into four grades. 

Grade I – Otherwise known as “sloppy knee cap.”  The patella will come out of the trochlea or groove it rests in.  It will pop back in on its own.  With Grade 1 luxations, if the patella is manually luxated, it realigns into the trochlea on its own. 

Grade II – The patella luxates and stays out of the trochlea.   When manually reduced into the trochlea, it stays inplace until it luxates again at a later time. 

Grade III – The patella is luxated all the time.   When reduced back into the trochlea, it won’t stay in place.  It pops back out immediately.  Generally, osteoarthritis is present in many cases. 

Grade IV – Same as Grade III, with significant bone remodeling and osteoarthritis.  Many of these cases have little to no trochlea present.


Surgery is required for Grades II through IV luxations.  Generally, a tibial crest transposition surgery is required at the same time as the trochlear wedge osteoplasty.


When treatment requires surgery, it is important to find out about post-operative care. Rehabilitation usually involves physiotherapy, hydrotherapy, medication, and regular vet visits. Some tips to speed up recovery include providing a nutrient-rich diet and avoiding strenuous activity or exercise initially. Professional therapy and rehab will help aid a quick recovery. Total recovery time after surgery usually takes 8-10 weeks.

Several exercises can help your dog in the recovery process. However, careful observation, appropriate exercise, and proper nutrition can help relieve discomfort and aid in the recovery process.  Over time, your pet will be back to his or her former self.

Not only does the Tampa Bay K9 Rehabilitation Center offer post-surgical physiotherapy, but we also can provide the surgery as well.

To know more about luxating patella, visit Tampa Bay K9 Rehabilitation Center at our office in St. Petersburg, Florida. You can also call us to book an appointment today.