Spontaneous Femoral Capital Physeal Fracture with Proximal Tibial Epiphyseal Dysplasia in a Cat

An 11-month-old, 5.6 kg, grade 4 on a 5-point scale body condition score, castrated male Korean short hair cat was presented with right hindlimb lameness for 3 days without trauma. On physical examination, severe pain with crepitation was elicited at the hip region but not at the stifle. Radiographic examination and computed tomography revealed a Salter-Harris type 1 fracture of the femoral capital physis and dysplasia of the proximal tibial epiphysis. Spontaneous femoral capital physeal fracture was suspected and femoral head and neck osteotomy was performed. Treatment for proximal tibial dysplasia was not performed. On histopathologic examination of femoral head, a cluster of chondrocytes in a proliferative zone at the epiphyseal plate was observed. Therefore, spontaneous femoral capital physeal fracture was diagnosed. The patient recovered his gait, and no related clinical signs were observed during 6 months of follow-up.