Use of a Custom-Made Patellar Groove Replacement in an American Staffordshire Terrier Puppy with a Severe Bone Defect in the Femoral Trochlea Caused by Hematogenous Osteomyelitis

An 8-months old male American Staffordshire terrier was referred for a no weightbearing lameness of the right pelvic limb, hyperthermia, lethargy and inappetence caused by hematogenous osteomyelitis. Orthopedic, radiographic and tomographic examinations revealed a bone sequestrum of 4 x 1.4 cm and active periosteal reaction of the caudo-lateral cortical in the metaphysis and the distal third of the right femoral diaphysis, medullary osteolysis and interruption of the cranio-medial cortical profile, with involvement of the femoral trochlea leading to a secondary medial patella luxation. Once skeletally mature, after 4 months from surgical debridement and aggressive antibiotic therapy against Klebsiella oxytoca revealed by bacteriological exam, the patient underwent prosthetic surgery for the application of a custom-made patellar groove replacement (PGR) to fill the bone defect and restore the femoral trochlea surface. Despite the serious injury that afflicted the right pelvic limb, the surgery had satisfactory outcomes until the last 18-months postoperative follow up.