Patellar luxation in rabbits (Oryctolagus cuniculus): 6 cases (2017-2020)

Abstract

Four cases of patellar luxation in rabbits have been reported in the literature, but the prevalence and etiology are unknown. This study aimed to characterize the presentation, anamnesis, prevalence, etiology, and treatment options for patellar luxation in rabbits. Medical records of 1249 rabbits presented to the Exotic Animal Service between January 2017 and March 2020 were reviewed. Data collection of the rabbits with patellar luxation included signalment, patient history, onset of lameness, position and grade of the luxation, radiographic findings, treatment, and clinical outcome. Six rabbits met the inclusion criteria (0.48% prevalence). The chief complaint in all rabbits was acute onset of hind limb lameness, ranging from weight-bearing to nonweight-bearing. The luxation was unilateral in all cases and ranged from grades II to IV. Four rabbits were managed medically with cage rest, but acute recurrence of the luxation was seen in two 18-month-old animals with grade III patellar luxation. Two 4-month-old animals with grade II patellar luxation responded well to medical treatment. Three rabbits, including one medically managed rabbit that reluxated, were managed surgically using soft tissue reconstruction described in dogs with traumatic patellar luxation. The methods included medial desmotomy, lateral imbrication, fabellotibial, and fabellopatellar sutures to stabilize supporting femoropatellar structures. A trochlear sulcoplasty was performed in one rabbit with grade IV luxation. At 12–24 months follow-up, reluxation had not occurred in the three rabbits. Patellar luxation is an uncommon cause of hind limb lameness in rabbits. Both medical and surgical treatment provided a good long-term outcome in five out of six patients. The surgery was relatively straightforward and took less than 1 hour in experienced hands. Further research is needed to determine the causes of patellar luxation in rabbits and to assess the indications, advantages, and complications of both treatments.