Abstract

Background:
Patellar luxation is a common orthopedic disorder in small-breed dogs that may result in persistent lameness, abnormal gait, and progressive joint degeneration. Bilateral grade III patellar luxation with opposite luxation directions in the same dog is rarely described in a previous study.

Case Description:
A two-year-old intact male Toy Poodle weighing 4.2 kg presented with chronic abnormal gait and persistent reduced right pelvic limb use. Orthopedic examination revealed bilateral patellar instability; both patellae could be manually reduced but readily eluated. Cranial drawer testing was negative. The hematologic and serum biochemical findings were within the reference intervals, and no clinically important systemic abnormalities were identified. Radiographic evaluation of both stifles confirmed bilateral grade III patellar luxation, lateral patellar luxation on the right side and medial patellar luxation on the left side, shallow trochlear grooves, and mild femorotibial malalignment. A staged surgical approach was selected. Trochlear ridge elevation was performed first on the right stifle and 20 days later on the left stifle using a comparable technique adapted to the luxation direction. Postoperative radiographs confirmed the reduction of both patellae within the TGs. Recovery was uneventful. Functional weightbearing returned after each procedure, and the dog showed normal walking and trotting, stable patellae on palpation, and no short-term postoperative complications 40 days after the first surgery.

Conclusion:
This case suggests that staged trochlear ridge elevation may be a feasible option in selected small dogs with bilateral grade III patellar luxation and opposite luxation directions, particularly when trochlear shallowness is the predominant anatomic abnormality and skeletal deformity is mild, as objectively confirmed by quantitative radiographic assessment (femoral angulation

Key words: Lateral patellar luxation; Medial patellar luxation; Patellar luxation; Toy Poodle; Trochlear ridge elevation.