Maggie, a 5-month-old female golden retriever, was presented 2 hours after her owner observed an acute onset of right pelvic limb lameness. No causative incident for the lameness had been observed.

Physical Examination

On physical examination, Maggie was bright, alert, and responsive. Vital parameters were within normal limits, aside from an elevated heart rate (140 bpm) presumably due to discomfort. Thoracic auscultation was within normal limits. She was nonweight-bearing on her right pelvic limb, and the stifle joint was visibly swollen with palpable pain. Range of motion in the right stifle was reduced. The remainder of the clinical examination was within normal limits.

Diagnosis

Differential diagnoses for this patient’s stifle swelling, pain, and lameness included fracture, patellar luxation, cranial cruciate ligament injury or avulsion, muscle or tendon strain, osteochondritis dissecans, and septic arthritis. Although there was no known trauma, fracture remained on the differential list, as juvenile bone is soft and the physes are weaker than the adjacent bone and ligaments, which can lead to fractures that can occur with little or no apparent trauma.^1-4 Early identification and treatment of physeal fractures are important to minimize the risk for development of significant limb deformities, joint incongruities, and intractable lameness.^1-3