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Patella Groove Replacement (PGR) in a Staffordshire Bull Terrier
Patella Groove Replacement
Stifle Stifle Cranio Caudal 07 03 2017 17 51 49 803
Patella Luxation Image

Patella Groove Replacement (PGR) is a partial joint replacement surgery where the groove in which the patella sits (trochlear groove) is replaced with a prosthesis.

PGR can be used in certain cases of patella (kneecap) luxation where the trochlear groove has been damaged due to osteoarthritis or if other options are not viable. You can read about canine patella luxation surgery here.

Diagnosis of patella luxation:

Signs of patella luxation include lameness and hopping or skipping on a back leg whilst walking A veterinary surgeon can diagnose this during a physical examination and may suggest x-rays to assess the problem and rule out other causes of knee pain.


This patient had a fracture of the tibial tuberosity as a puppy resulting in poor patella tracking leading to patella luxation. The deformity resulting from the original fracture excluded Tibial Tuberosity Transposition (TTT/TCT - please see the Patella Luxation information sheet) as a treatment. Surgery involved an incision over the knee joint, the groove removed using a specialist orthopaedic saw and a base plate secured to the new surface. Once the surgeon was happy it was in the correct position by checking it using a ‘dummy’ implant, the titanium implant was attached to the plate and the patella relocated into the artificial groove.

Post operative:

After 6 weeks of strict rest x-rays showed that the patient had good boney growth into the base plate and that the patella was moving through the groove correctly. This patient made a full recovery and returned to full activity.