Radiographic changes of the patellar ligament in dogs after tibial tuberosity advancement

Abstract

Patellar desmopathy in dogs after tibial plateau levelling osteotomy has been described in many studies. Tibial tuberosity advancement is a biomechanically different technique. It is assumed that the patellar ligament is loaded with little force similarly as after tibial plateau levelling osteotomy. Various aspects related to secondary patellar desmopathy are not completely understood. This study deals with computed radiography measurement of patellar ligament thickness after tibial tuberosity advancement in dogs with cranial cruciate ligament rupture. The thickness of the patellar ligament in exactly predetermined locations was measured from mediolateral radiographs of stifle joints. A total of 18 dogs (20 knee joints) with cranial cruciate ligament (ligamentum cruciatum craniale) rupture underwent three radiographic examinations of the knee (preoperative examination and control examination 7 and 15 weeks after the surgery). Significant difference was found between the thickness of the patellar ligament in the first and second examinations. Some of the demographic factors possibly related to patellar ligament thickness (age, sex, body weight, type of cranial cruciate ligament rupture, arthrotomy, cage size, meniscal injury, time between surgery and radiographic examination) were analyzed. However, statistical analyses did not show any effect of these factors on the thickness of the patellar ligament, except for the time between surgery and radiographic examination. These findings can extend the surgeons’ knowledge of biomechanical aspects of tibial tuberosity advancement.