What is Medial Patella Luxation? 

The patella, or kneecap, is typically stabilized by a groove in the femur. In cases of medial patellar luxation (MPL), this groove may be too shallow or the surrounding structures may be misaligned, allowing the patella to dislocate (slip out), especially during knee flexion.​ This occurs because the patella doesn't stay properly seated within the groove on the end of the femur (thigh bone). It's a common problem, especially in smaller breeds, and can lead to lameness and pain. Dogs with MPL may show a "skip" or "bunny hop" in their gait, suddenly lifting one hind leg while walking or running. Medial patella luxation is graded from 1 to 4, with grade 1 being mild and grade 4 being the most severe. Higher grades often require surgery. ​

This radiograph shows the patella out of the trochlear groove

Treatment for MPL

Since every dog is shaped differently, there are a variety of methods to treat MPLs. Typically a combination of multiple techniques are used to achieve greatest stability of the patella back into the groove without further dislocation. Techniques include but are not limited to: 
• Tibial Tuberosity Transposition (TTT)
• Desmotomy 
• Trochleoplasty 
• Lateral Retinacular Imbrication 
• Tibial Derotational Suture