Rotatory intra-articular dislocation of the patella in two dogs.

Two young (8 and 13 week old) dogs were referred for evaluation of acute lameness. Physical examination, radiography, and surgical exploration of their stifles confirmed rotatory intra-articular dislocations of the patella. The dislocated patellas were stabilized with wire into their anatomically correct positions and allowed to heal. Follow-up radiography revealed patellar elongation attributable to excessive peripatellar mineralization. Patellar orientation, as evident on radiographs obtained after trauma, may indicate whether closed or open reduction of these injuries is necessary.

Carpal accessorioulnar joint fusion in a dog.

Traumatically induced lateral subluxation of the accessory carpal bone in a dog resulted in chronic lameness with weight-bearing instability. Accessorioulnar carpal joint arthrodesis was performed, using one interfragmentary lag screw and a cancellous bone graft. The lameness subsided and clinical function has remained excellent for 32 months. Low-grade osteoarthritis of other carpal joints has progressed, but may relate to other damage sustained at the time of initial injury. Focal intercarpal joint arthrodesis in this dog provided clinical function that far surpassed that of pancarpal arthrodesis, the logical surgical alternative for such an injury.

Anterior cruciate ligament replacement using patellar tendon. An evaluation of graft revascularization in the dog.

UNLABELLED: We investigated the revascularization pattern of patellar tendon grafts used to replace the anterior cruciate ligament in thirty-six dogs by histological and tissue-clearing (Spalteholz) techniques. Initially the grafts were avascular, but by six weeks they were completely ensheathed in a vascular synovial envelope. The soft tissues of the infrapatellar fat pad, the tibial remnant of the anterior cruciate ligament, and the posterior synovial tissues contributed to this synovial vasculature. Intrinsic revascularization of the patellar tendon graft progressed from the proximal and distal portions of the graft centrally and was complete by twenty weeks. The tibial attachment of the patellar tendon graft did not contribute any vessels to the revascularization process. At one year, the vascular and histological appearance of the patellar tendon graft resembled that of a normal anterior cruciate ligament. CLINICAL RELEVANCE: The absence of perfused vessels within the patellar tendon graft immediately after transplantation within the knee joint and the failure of the osseous insertion of the graft to contribute vessels to the revascularization process suggest that although it is left attached at the tibia, the patellar tendon graft is essentially an avascular free graft at transplantation. The contribution of the soft tissues of the knee to the revascularization process of the graft suggests preservation and utilization of the infrapatellar fat pad and synovial tissue to optimize the graft's revascularization and ultimate viability.

Repair of fractured capital femoral epiphysis in two sheep.

Fracture of the capital femoral epiphysis occurred in two sheep. Both fractures were repaired via open reduction and lag screw fixation. A craniolateral approach to the hip (modified Watson-Jones) afforded good exposure and allowed manipulation with minimal soft tissue trauma. Rigid internal fixation in each case resulted in good long-term results. It was concluded that repair of this type of fracture in sheep is feasible if the animal is valuable.