Reverse TPLO for asymmetrical -premature closure of the proximal tibial physis in a dog.

A 4.5-month-old, 13.8 kg, female neutered mixed breed dog was presented for evaluation of acute non-weight bearing right pelvic limb lameness. Radiographs revealed a tibial tuberosity avulsion fracture for which open reduction/internal fixation was performed. Asymmetrical premature closure of the cranial aspect of the proximal tibial physis ensued with a tibial plateau angle of -12°. Abnormal stifle biomechanics resulted in lameness and caudal cruciate ligament fraying. Tibial plateau levelling osteotomy was performed in standard fashion with the exception that the proximal tibial fragment was rotated cranioproximally to increase the tibial plateau angle from -12° to +5° (reverse tibial plateau levelling osteotomy). Normal healing and resolution of lameness followed and the dog remained clinically healthy 2 years postoperatively. This case report demonstrates that any change in proximal tibial anatomy, whether traumatic, iatrogenic or with therapeutic intent, can cause altered stifle biomechanics and should not be underestimated. Surgical management through corrective osteotomy can be used to restore adequate function.