Patellofemoral contact mechanics after transposition of tibial tuberosity in dogs

Abstract

Background: Tibial tuberosity transposition (TTT) causes caudalization of the patellar ligament insertion in canine medial patellar luxation, which can lead to increases in patellofemoral contact pressure. Objectives: The purpose of this study is to confirm the effect of patellofemoral contact mechanics after craniolateral and caudolateral transposition of tibial tuberosity in normal canine hindlimbs. Methods: Craniolateral and caudolateral transposition of tibial tuberosity was performed in 5 specimens, respectively. The pressure was measured in the specimen before TTT, and then in the same specimen after TTT. In this process, data was obtained in 10 specimens. The measurement results were output as visualization data through the manufacturer's software and numerical data through spreadsheet. Based on these 2 data and the anatomical structure of the patellofemoral joint (PFJ) surface, whole measurement area was analysed by dividing into medial, lateral and central area. Results: In craniolateralization of tibial tuberosity, total, medial, central contact pressure was decreased and lateral contact pressure was not statistically changed lateral contact pressure than normal PFJ. In caudolateralization of tibial tuberosity, total, lateral contact pressure was increased and medial contact pressure was not statistically changed than normal PFJ. Although not statistically significant changed, central contact pressure in caudolateralization of tibial tuberosity was increased in all 5 specimens. Conclusions: These results imply that traditional TTT, prone to caudal shift of patellar tendon, can increase retropatellar pressure may lead to various complications and diseases of the stifle joint.

Comparison of patellofemoral contact pressure after semi-cylindrical recession trochleoplasty and trochlear block recession in feline cadavers

“…Realistically, the side-effects of osteotomy procedures include higher contact pressures (18). Human TD patients showed increased contact pressure and decreased contact area (12), which is consistent with the results of this experiment.…”

“…In TBR procedures, distal trans-trochlear cuts are made perpendicular to the trochlear sulcus and a straight basilar cut connects proximal and distal trans-trochlear margins ( 19 ). Realistically, the side-effects of osteotomy procedures include higher contact pressures ( 18 ).…”

“…This study has some limitations. First, the cadaveric feline stifle model was modified from a previous ex vivo model ( 18 ). Although it reproduced the quadriceps and hamstring muscle mechanism in a standing posture for feline stifles in vivo , it cannot represent all elements.…”

“…In preparation for the experiment, the specimens were thawed at room temperature under moisture gauzes. The setting of the experiment was modified from selected previous studies ( 17 , 18 ). A Krackow suture was performed on the quadriceps muscle using a braided steel cable, and the cable was secured by connecting it to a screw placed at the proximal femur, imitating the mechanism of the quadriceps muscle.…”

“…The angles were measured by an electronic goniometer. The pressure on the PFJ was measured as a load of 30% body weight in the specimens ( 18 ). To prevent slipping, commercially available sandpaper was attached to the contact area of the palmar pad, with the force-sensitive resistor (TFM 4800, Kitronyx Inc., Seoul, South Korea) placed between the patella and the trochlear groove ( Figures 1B , C ).…”