Comparison of Trochlear Block Recession and Trochlear Wedge Recession in Four Dogs with Bilateral Patellar Luxation Confronto Fra “solcoplastica a Cuneo” E “solcoplastica En Block” in Quattro Cani Con Lussazione Rotulea Bilaterale

Patellar luxation is the result of progressive structural abnormalities in the soft and/or skeletal tissues of the dog’s pelvic limbs. There is an alteration of the patella-trochlear groove interaction with negative effects on the stifle stability and extensor mechanism integrity, on the trochlear articular cartilage nutrition and the adequate trochlear depth and length development and maintenance. This is the reason for which there is a progressive trochlear groove levelling in the cases of severe patellar luxation; therefore, it is necessary to correct the trochlear depth abnormality to make patellar sliding action into the trochlear recess easier and to achieve consistent success with surgical treatment. Traditional methods to improve trochlear depth include the chondroplasty in the very young dogs, and the wedge recession trochleoplasty or TWR (trochlear wedge recession) in adult subjects. A modification of the technique called “trochlear block recession” (TBR) has recently been described from Talcott et al. in 2000. Block recession is identical in principle to wedge recession, except that a rectangular piece of cartilage and bone, rather than a wedge, is removed. The TBR seems to guarantee an adequate trochlear depth and width, the maximal preservation of hyaline articular cartilage and the secure implantation of the osteochondral autograft. The Authors report their clinical experience about four dogs affected by bilateral patellar luxation, treated with the TWR at one stifle and the TBR at the controlateral one in the same surgical session. In our study, we compared the trochleoplasty techniques, evaluating both the recuperated function of the limb, and the anatomic correction obtained, through clinical and computer tomography examinations. Both the trochleoplasty techniques proved clinical efficiency; at the postoperative examinations, all the articulations were adequatelly stabilised and there were no complications or relapses in any of the cases; also the return to complete function of limb was rather rapid. The TBR, notwithstanding the modest executive difficulties and the slower recovery caused by a more invasive procedure, assures the best anatomical correction of the trochlear defect and increases the patellar stability in extended stifle position; it assent to obtain an adequate trochlear depth without weakening either the trochlear ridges or femoral distal epiphysis, not even in small dogs.