A two-and-a-half-year-old giant lop-eared rabbit, weighing 5.1？kg, presented with a one-month history of intermittent right hind limb lameness. The limb locked in extension during hopping. On examination, a grade-2 medial patellar luxation of the right hind was diagnosed, with associated stifle joint swelling. Radiographic findings of the right stifle comprised periarticular osteophyte formation consistent with mild degenerative joint disease and joint effusion. Surgical correction involving right trochlear wedge recession sulcoplasty and lateral imbrication was carried out to stabilise the patella in the trochlear groove. The right hind limb lameness resolved, and the patella was stable at a 6-month postoperative examination. One year postoperatively, the right patella was luxating again concurrent with bilateral stifle effusions. Euthanasia was performed twenty months after surgery due to recurrent lameness in the right hind limb. 1. Introduction Patellar luxation is a common disorder of the stifle, predominantly affecting small-breed dogs [1] but increasingly prevalent in larger-breed dogs [2] and cats [3, 4]. Medial luxation is reported more commonly in young, small-breed dogs with developmental disease and in cats [3, 5]. Approximately 50% of medial patellar luxation cases in dogs display bilateral involvement [6]. Clinical signs vary, according to the severity of the anatomical derangements and the degree of luxation, from intermittent, nonpainful, “skipping” lameness, reluctance to jump, and crouched gait to severe lameness and skeletal deformities. In contrast to patellar luxation in dogs and cats, there is a lack of the literature regarding this condition, and other developmental orthopaedic abnormalities, in the rabbit species. Unilateral (left) medial patellar luxation with degenerative joint disease of the stifle has been described in a 1-year-old rabbit, concurrent with a shortened left femur, a shallow trochlear groove, a rotated proximal left tibia, and a left hip subluxation [7]. As this rabbit was ambulatory and not apparently painful, no treatment was given. Another report described bilateral medial patellar luxation in a 5-month-old rabbit [8] resulting in impaired mobility, but conservative management was elected. To the authors’ knowledge, no reports of surgically corrected patellar luxation in the rabbit currently exist. This case report describes clinically significant patellar luxation in a pet rabbit in the UK and demonstrates the role of surgery in its management. 2. Case Presentation A two-and-a-half-year-old, male neutered,
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