Tibial tuberosity transposition-advancement for treatment of medial patellar luxation and concomitant cranial cruciate ligament disease in the dog. Surgical technique, radiographic and clinical outcomes.

OBJECTIVE

To report surgical technique, morphometric effects and clinical outcomes for tibial tuberosity transposition-advancement (TTTA), sulcoplasty and para-patellar fascial imbrication for management of concomitant medial patellar luxation (MPL) and cranial cruciate ligament (CCL) disease in 32 dogs.

STUDY DESIGN

Case series.

METHODS

A previous technique for tibial tuberosity advancement was modified to incorporate lateral and distal tibial tuberosity transposition. Preoperative, immediate, and six to eight week postoperative radiographs were reviewed with morphometry of a range of tibial and stifle anatomic parameters. Findings of sequential clinical examinations to six to 20 months postoperatively were recorded.

RESULTS

Thirty-nine stifles were treated by surgery. Medial patellar luxation grade ranged from II to IV/IV. The CCL rupture was complete in 17/39 stifles, and incomplete in 22/39. Complications occurred in 11/39 stifles including MPL recurrence (n=4). Resolution of subjectively-assessed lameness occurred in 29/39 stifles at the six to eight week assessment. Resolution of lameness was eventually documented in 35/39 stifles (4/39 lost to follow-up), and was maintained at the six to 20 month reassessment where available. The TTTA induced relative patella baja in 31/39 stifles. Magnitude of actual tibial tuberosity advancement was lower than that predicted by cage size.

CLINICAL SIGNIFICANCE

Tibial tuberosity transposition-advancement is a potential treatment modality for concomitant CCL disease and MPL in the dog, but refinement of planning is required, while biomechanical and kinematic effects remain unknown.