Therapy for Cranial Cruciate Ligament Rupture - What Has Been Done so Far

Introduction
Little information exists in the literature about therapy outcomes after conservative or surgical treatment of cranial cruciate ligament rupture in cats.

For a long period conservative treatment has been advocated to be the best option. The cat is confined to cage rest for 4-6 weeks and treated for the first couple of days with NSAIDs. Study results showed that a nearly or complete restoration of gait was observed within 3-4 months. With the use of gait analysis, a study pointed out, that peak vertical forces in the affected hind limb never reached the same values. Many cats had progressive signs of osteoarthritis (>80%), joint instability, medial capsular thickening and muscle atrophy. Authors speculate that surgical intervention might minimize and reduce the progression of secondary degenerative joint changes and restore full limb function earlier.Similar to the dog, there are several surgical therapy options in cats. Depending on the surgeon’s preference either an intraarticular or extraarticular technique is chosen.

Intraarticular procedures use fascia, parts of the patellar tendon (over the top) or synthetic material (Westhues) to reconstruct the ruptured ligament. The lateral retinacular imbrication technique is most commonly used, because it is easy to perform, less invasive than intraarticular techniques and cheaper. A standard lateral approach to the stifle joint, debridement and closure of the joint capsule is performed. A nylon leader line (23kg breaking strain) or monofilament suture (2-0) is placed between a bone tunnel of the tibial tuberosity (drilled transversely or with a slight angle to reduce stress on the suture material) and the lateral fabella. In contrast to the medial fabella, which in non-pedigree cats consists mostly of fibrocartilage and is radiolucent, the lateral fabella is normally ossified. The lateral facia is imbricated and the subcutaneous and skin layers are closed continuously or in a simple interrupted pattern.  [...]