Patellar Luxation

Patellar luxation is a condition in which the patella, commonly known as the kneecap, slips out of its normal position in the trochlear groove of the femur, disrupting the normal function of the stifle joint. This condition affects the rabbit's ability to extend the hind leg properly, as the patella serves as an essential component of the quadriceps mechanism that straightens the leg during hopping. In rabbits, patellar luxation is most commonly a developmental or congenital condition, meaning it results from abnormal formation of the stifle joint structures during growth, though traumatic luxation can also occur following injury. The condition varies widely in severity, from occasional mild slipping that causes intermittent gait abnormalities to permanent displacement that significantly impairs mobility.

The patella normally sits within a groove called the trochlea, located on the front surface of the lower femur where it articulates with the tibia to form the stifle joint. During leg movement, the patella glides up and down within this groove, protected by the surrounding joint capsule and held in place by the alignment of the quadriceps muscle, patellar ligament, and the shape of the groove itself. In patellar luxation, abnormalities in one or more of these components allow the patella to slip out of the groove, typically moving toward the inside of the leg in medial luxation, which is more common, or toward the outside in lateral luxation. Once displaced, the patella may spontaneously return to position, may be manually replaceable, or may remain permanently luxated depending on severity.

The impact of patellar luxation on a rabbit's health depends greatly on the grade of luxation and whether one or both legs are affected. Mild cases may cause only occasional skipping gait during movement, with the rabbit appearing normal most of the time. More severe cases result in persistent lameness, abnormal leg carriage, and eventually degenerative changes in the joint from the abnormal mechanics. Bilateral involvement, affecting both hind legs, is particularly problematic as it compromises the rabbit's ability to hop, groom, and consume cecotropes properly. Because rabbits hide illness, the discomfort from patellar luxation may not be obvious even when present, requiring careful observation to detect gait abnormalities.

Treatment options for patellar luxation in rabbits range from conservative management with weight control, environmental modification, and pain management to surgical correction for more severe cases. Prognosis is generally good for mild cases managed conservatively and for surgically corrected moderate to severe cases, though some rabbits experience progressive joint degeneration despite treatment. Early detection and appropriate management by a rabbit-savvy veterinarian experienced in orthopedic conditions help achieve the best outcomes. Affected rabbits should not be bred, as the condition has a genetic component that would be passed to offspring.

The primary causes of patellar luxation in rabbits are developmental abnormalities affecting the structures that normally keep the patella in position within the trochlear groove. Shallow trochlear groove is a common finding, where the channel that should contain the patella is not deep enough to prevent displacement during movement. Abnormal alignment of the quadriceps muscle group and patellar ligament creates forces that pull the patella to one side rather than keeping it centered. Malformation of the distal femur or proximal tibia may angle the joint surfaces in ways that promote luxation. These developmental abnormalities typically become apparent during growth and may worsen as the rabbit matures and gains weight.

Genetic factors play a significant role in patellar luxation, with the condition showing familial patterns and breed predispositions. While specific genes responsible for patellar luxation in rabbits have not been definitively identified, the inheritance pattern suggests a polygenic trait influenced by multiple genes affecting limb development and joint formation. Breeding of affected individuals perpetuates the genetic predisposition in offspring. Dwarf breeds appear predisposed, likely related to the genetic changes that produce dwarfism also affecting limb conformation. Inbreeding within breed lines may concentrate genes predisposing to skeletal abnormalities. Responsible breeders should avoid breeding rabbits with patellar luxation or other conformational abnormalities.

Environmental factors during development may influence expression of genetic predisposition to patellar luxation. Nutritional factors affecting bone and cartilage development could potentially modify joint formation, though specific nutritional causes are not well documented in rabbits. Excessive growth rates, particularly in predisposed breeds, may outpace proper joint development. Activity levels during growth theoretically could influence how joints develop, though this is speculative. Slippery flooring during the growth period might affect leg muscle development and joint forces in ways that could promote abnormal patellar tracking. However, in most cases, the developmental abnormality is primarily genetic rather than environmentally caused.

Risk factors for patellar luxation include breed predisposition, particularly in dwarf breeds, and any observable limb deformities. Rabbits with bowed or crooked legs, angular limb deformities, or other skeletal abnormalities are more likely to have associated patellar problems. Obesity places increased stress on joints and may worsen symptoms in predisposed rabbits. Previous trauma to the stifle area could potentially cause or exacerbate luxation. Rabbits from pet stores or backyard breeders where health screening is not practiced may be at higher risk than those from responsible breeders who screen for orthopedic abnormalities.

The mechanism by which patellar luxation causes problems relates to disruption of normal leg extension. When the patella is in its proper position within the trochlear groove, the quadriceps muscle contraction is efficiently transmitted through the patella and patellar ligament to straighten the leg. When the patella luxates, this mechanism is disrupted, and the leg cannot extend properly. The rabbit may skip or hop abnormally as they compensate. If the patella remains displaced, the abnormal position causes stretching of supporting soft tissues on one side and contracture on the other, making return to normal position increasingly difficult. Over time, the abnormal mechanics cause cartilage wear and degenerative joint disease, creating a painful arthritic condition in addition to the mechanical dysfunction.

Early warning signs of patellar luxation may be very subtle, particularly in grade one luxation where the patella can be manually displaced but returns to position spontaneously. Owners may notice occasional hesitation or mild skipping gait in one hind leg that resolves quickly. There might be brief moments during hopping where the rabbit seems to stumble slightly or move awkwardly before resuming normal motion. Young rabbits during growth may show developing gait abnormalities that become more apparent over time. Because rabbits naturally hide weakness, early signs may be easy to miss without careful observation during active movement. Any rabbit who shows occasional hind limb abnormalities should be evaluated for possible patellar or other stifle problems.

Common symptoms of established patellar luxation vary by grade and chronicity. Intermittent skipping or hopping on three legs occurs when the patella is displaced and then returns to position. The affected leg may appear to suddenly give out briefly during movement. In more severe cases, the rabbit may consistently carry the affected leg in an abnormally flexed position. The hop may appear asymmetrical, with the affected side showing reduced push-off. Some rabbits develop a characteristic movement pattern where they seem to kick out or flick the affected leg during motion, which may represent attempts to replace a displaced patella. Over time, muscle wasting may develop in the affected thigh as the rabbit uses the leg less.

Behavioral changes associated with patellar luxation reflect adaptation to the condition and any associated discomfort. Rabbits may become less active overall, avoiding activities that stress the affected joint. Reluctance to hop, jump, or run that was previously enjoyed may indicate joint discomfort. Changes in posture, with more weight shifted to the unaffected limb, may be observable. If the condition causes pain, decreased appetite may occur, though this is less common in mild to moderate patellar luxation than in more painful conditions. Difficulty grooming the hindquarters or consuming cecotropes may develop if hind limb function is significantly compromised. Teeth grinding during rest may indicate pain in more severe cases.

Physical signs observable during examination include palpable displacement of the patella from its normal central position over the trochlear groove. The veterinarian can often feel the patella move out of position during manipulation and assess whether it returns spontaneously or must be replaced manually. In severe cases, the patella may be permanently displaced to the inside or outside of the joint. The affected leg may show reduced range of motion, particularly in extension. Muscle mass may be decreased in the affected thigh compared to the opposite leg. Crepitus, a grinding sensation, may be felt during joint manipulation if degenerative changes have developed. Angular limb deformities or other conformational abnormalities may be visible in affected rabbits.

Symptom progression in patellar luxation typically involves gradual worsening over time, particularly in untreated higher-grade luxations. The frequency of luxation episodes tends to increase as supporting structures stretch. Intermittent luxation may progress to more frequent or permanent displacement. Degenerative joint disease develops as abnormal mechanics cause cartilage wear, adding pain and stiffness to the mechanical dysfunction. Muscle atrophy becomes more pronounced. Rabbits may become progressively less mobile. In bilateral cases, overall mobility may become severely compromised.

Emergency symptoms associated with patellar luxation are uncommon, as this is typically a chronic condition rather than an acute emergency. However, if a rabbit with patellar luxation suddenly becomes completely non-ambulatory, stops eating, or shows signs of severe pain, emergency evaluation is warranted as concurrent problems may have developed. Any rabbit not eating for more than twelve hours requires urgent attention due to the risk of GI stasis. If patellar luxation has progressed to the point where the rabbit cannot reach cecotropes, cannot access food and water normally, or has no quality of life, urgent veterinary consultation is needed to discuss management options. Acute injury to an already compromised joint may cause sudden worsening requiring immediate evaluation.

Initial veterinary examination for suspected patellar luxation involves observation of gait and physical examination of the stifle joints by a rabbit-savvy veterinarian. The veterinarian will first observe the rabbit moving freely if possible, watching for skipping, limb carriage abnormalities, or gait asymmetry. Physical examination includes careful palpation of both stifle joints, comparing sides. The veterinarian locates the patella and assesses whether it is in normal position, can be manually displaced, returns to position spontaneously or only with manual replacement, and whether it remains permanently luxated. The direction of luxation, medial or lateral, is noted. Overall limb conformation is evaluated for angular deformities or other abnormalities that commonly accompany patellar luxation. Range of motion, joint stability, and pain response are assessed.

Grading systems for patellar luxation help characterize severity and guide treatment decisions. Grade one luxation means the patella can be manually displaced from the trochlear groove but returns to normal position spontaneously when released. Grade two means the patella luxates spontaneously during normal movement or can be manually displaced and remains displaced until manually replaced. Grade three means the patella is displaced most or all of the time but can be manually replaced, though it immediately reluxates. Grade four means the patella is permanently displaced and cannot be manually replaced. Higher grades generally indicate more significant structural abnormalities and greater impact on function. Both knees should be evaluated and graded independently as severity may differ between sides.

Diagnostic imaging confirms the diagnosis and helps plan any surgical intervention. Radiographs of the stifle joints show the position of the patella, the depth and conformation of the trochlear groove, alignment of the femur and tibia, and any degenerative changes such as osteophyte formation. Positioning for stifle radiographs in rabbits can be technically challenging and may require sedation. Comparison of affected and unaffected joints helps characterize abnormalities. Advanced imaging such as CT scanning may provide more detailed assessment of bone structure if surgery is planned, though this is not routinely necessary for diagnosis. Radiographs also help rule out other conditions that could cause similar symptoms.

Differential diagnosis considers other causes of hind limb lameness and abnormal gait in rabbits. Hip dysplasia or luxation causes similar hind limb lameness but affects a different joint. Stifle injuries including cruciate ligament rupture or other trauma cause acute stifle dysfunction. Fractures of the femur, tibia, or patella require differentiation. Spinal conditions causing hind limb weakness may initially appear similar. Infectious arthritis causes joint pain and lameness but typically includes systemic illness. Encephalitozoon cuniculi can cause hind limb weakness through neurological effects. Physical examination and imaging distinguish between these conditions, though multiple problems may coexist.

Conservative management is appropriate for grade one and some grade two patellar luxations, particularly when symptoms are mild and the rabbit maintains good mobility. Weight management is essential, as maintaining lean body condition reduces stress on the affected joint. Environmental modifications include non-slip flooring throughout the living area to prevent slipping that could exacerbate luxation. Activity modification may involve limiting high-impact activities while encouraging gentle movement that maintains muscle strength. Pain management with meloxicam or other rabbit-safe analgesics addresses any discomfort. Joint supplements containing glucosamine, chondroitin, and omega-3 fatty acids may provide supportive benefit for cartilage health. Regular monitoring tracks progression, with treatment intensity increasing if the condition worsens.

Medical management for symptomatic patellar luxation centers on pain control and slowing degenerative progression. Meloxicam is the mainstay of pain management in rabbits, providing both analgesic and anti-inflammatory effects. Dosing must be appropriate for rabbits, which metabolize the drug differently than cats or dogs. For rabbits with more significant pain, additional analgesics such as tramadol or gabapentin may be added. Long-term anti-inflammatory use requires periodic monitoring of kidney and liver function. Weight management is critically important, as even moderate obesity significantly increases joint stress. Dietary management emphasizes unlimited hay with carefully measured pellets and appropriate vegetables to maintain lean body condition without nutritional deficiencies.

Surgical treatment is indicated for higher-grade luxations, cases not responding to conservative management, and young rabbits where early intervention may prevent degenerative progression. Surgical options vary depending on the specific anatomical abnormalities present. Trochlear deepening procedures create a deeper groove to better contain the patella. Tibial tuberosity transposition moves the attachment point of the patellar ligament to correct alignment. Soft tissue procedures tighten loose structures and release contracted tissues to rebalance forces on the patella. Often, combinations of procedures are needed to address multiple abnormalities. Surgery in rabbits requires an experienced exotic animal orthopedic surgeon and careful anesthetic management. Rabbits should not be fasted before surgery. Post-operative care includes pain management, strict rest, and physical therapy.

Supportive care throughout treatment addresses the rabbit's overall wellbeing. Ensuring adequate nutrition with unlimited hay prevents GI stasis, a concern in any rabbit experiencing pain or undergoing medical treatment. Hydration should be monitored, with subcutaneous fluids provided if intake is inadequate. Comfortable housing with soft bedding supports rest without putting pressure on joints. Environmental enrichment appropriate to activity restrictions maintains mental wellbeing. Physical therapy exercises, when appropriate, help maintain muscle strength and joint mobility. Close monitoring of food intake and fecal output catches any developing GI issues early.

Alternative and complementary treatments may supplement conventional management. Gentle massage of the thigh muscles can improve comfort and circulation. Range of motion exercises maintain joint flexibility. Acupuncture has been used for pain management in animals with arthritis and may provide benefit. Laser therapy may help reduce inflammation and promote healing. These approaches should complement, not replace, appropriate veterinary care including pain management and surgical intervention when indicated.

Treatment decisions balance the severity of the condition, the rabbit's age and overall health, response to conservative measures, and practical considerations. Grade one luxation often needs only monitoring and preventive measures. Grade two requires conservative management and monitoring for progression. Grades three and four typically require surgical intervention for best outcomes. The owner's ability to provide post-surgical care, including strict rest and physical therapy, affects surgical success. Costs of surgery and long-term management should be discussed realistically. For bilateral cases, staging surgery on one leg at a time allows the rabbit to remain ambulatory on the unoperated leg during recovery.

Recovery from surgical patellar luxation correction requires several weeks of restricted activity followed by gradual return to normal function. The initial two to four weeks following surgery require strict cage rest to protect the repair while healing occurs. The rabbit is confined to a small, padded enclosure with food, water, hay, and litter box easily accessible. No jumping, running, or vigorous activity is permitted. Pain medication continues throughout this period, with adjustments based on the rabbit's comfort. Gentle passive range of motion exercises may be recommended after the first week to prevent joint stiffness. By four to six weeks, if healing is progressing well, gradually increasing activity is allowed under veterinary guidance. Full recovery may take eight to twelve weeks or longer.

Post-treatment care involves close monitoring during the recovery period. Incision site monitoring ensures proper healing without infection, swelling, or opening of the wound. Bandages or splints, if used, require regular changes and skin monitoring underneath. Medication administration continues as prescribed, with owners learning proper techniques for giving oral medications to rabbits. Food intake and fecal output must be monitored daily, with any decline prompting immediate intervention to prevent GI stasis. Follow-up veterinary appointments assess healing progress and determine when activity can increase. Physical therapy exercises progress as healing allows, gradually building strength and mobility in the repaired limb.

Prognosis for patellar luxation depends on grade, treatment approach, and presence of pre-existing joint degeneration. Mild cases managed conservatively often maintain acceptable function long-term with appropriate weight management and activity modification. Surgical correction of grade two through four luxation has good success rates in experienced hands, with most rabbits achieving significantly improved mobility and reduced pain. Higher grades and cases with significant pre-existing arthritis have somewhat less favorable outcomes. Young rabbits treated before significant degenerative changes develop generally have better prognosis than older rabbits with chronic luxation. Bilateral cases require careful management but can achieve good outcomes with staged surgical correction.

Long-term outlook following patellar luxation treatment requires ongoing attention to joint health. Even with successful treatment, degenerative joint disease may progress over time, particularly in rabbits who had significant arthritis before treatment. Regular veterinary monitoring, typically every six to twelve months for stable cases, allows early detection of progressive changes. Weight management remains critically important throughout life. Pain medication may be needed intermittently or continuously as the rabbit ages. Activity modification may be permanent for some rabbits. With appropriate management, many rabbits with patellar luxation maintain good quality of life for their normal lifespan, enjoying activities within their physical abilities.

Primary prevention of patellar luxation focuses on responsible breeding practices, as the condition has significant genetic components. Rabbits with patellar luxation should not be bred under any circumstances, even if the condition is mild. Breeding stock should be evaluated for orthopedic soundness before breeding. Physical examination by a rabbit-savvy veterinarian can identify patellar instability. Breeders should track health problems in their lines and select away from conformational abnormalities. Prospective pet owners should seek rabbits from responsible breeders who screen for health issues rather than from pet stores or casual breeders where health history is unknown. When adopting rescue rabbits with unknown backgrounds, orthopedic evaluation can identify existing issues.

Environmental prevention measures reduce the impact of existing patellar instability and may prevent traumatic luxation. Provide non-slip flooring throughout all areas where the rabbit moves, as slippery surfaces increase joint stress and injury risk. Avoid wire-bottom cages, which are harmful to rabbit feet and do not support normal movement. Ensure safe environments that minimize risk of falls or injuries. Appropriate enclosure size allows exercise without excessive jumping stress on vulnerable joints. Remove or modify access to high surfaces that require large jumps. For rabbits with known mild patellar instability, environmental modifications may prevent progression to more significant luxation.

Dietary prevention supports joint health and maintains appropriate body weight. Unlimited grass hay forms the foundation of rabbit nutrition and provides appropriate fiber without excessive calories. Measured pellet portions prevent obesity while ensuring adequate nutrition. Fresh leafy greens provide vitamins and minerals supporting overall health. Avoid high-calorie treats and sugary foods that promote weight gain. Clean, fresh water should always be available. Maintaining lean body condition throughout life reduces stress on all joints, including the stifle. For growing rabbits, appropriate nutrition supports proper bone and joint development without promoting excessively rapid growth.

Health maintenance practices help identify patellar problems early and maintain overall musculoskeletal health. Regular veterinary examinations with a rabbit-savvy veterinarian allow early detection of developing joint problems. Annual or twice-yearly wellness visits should include orthopedic assessment. Weight monitoring at home identifies trends before significant obesity develops. Appropriate exercise maintains muscle strength that supports joints. Grooming sessions provide opportunity to observe the rabbit's movement and detect any gait abnormalities. Report any lameness, skipping gait, or reluctance to move normally to the veterinarian promptly.

Early intervention when patellar instability is identified can prevent progression to more serious disease. Rabbits identified with grade one luxation should begin preventive management including weight control and environmental modification. Regular monitoring allows early detection of worsening. If progression occurs, treatment intensity can be increased before significant degenerative changes develop. Young rabbits with moderate luxation may benefit from early surgical correction before chronic changes make surgery less effective. Working with a veterinarian experienced in rabbit orthopedics ensures appropriate monitoring and timely intervention.

Daily management for rabbits with patellar luxation focuses on maintaining comfort, supporting joint health, and monitoring for changes. Administer any prescribed medications consistently, learning proper techniques for oral medication administration to minimize stress. Monitor the rabbit's mobility daily, noting any changes in gait, activity level, or apparent discomfort. Watch for signs of pain such as teeth grinding, decreased appetite, reluctance to move, or hunched posture. Track food and water intake to ensure adequate nutrition and hydration. Check fecal output daily, as any decrease may indicate developing GI issues requiring prompt attention. Regular gentle handling allows ongoing assessment of body condition and muscle mass.

Home environment should be optimized for rabbits with stifle problems. Non-slip flooring is essential throughout all areas accessible to the rabbit, as slipping stresses the stifle joint and can worsen luxation. Use textured mats, carpet, fleece blankets, or rubber mats over smooth surfaces. The living enclosure should be single-level or have very gentle ramps rather than requiring jumping. Low-entry litter boxes reduce strain when entering and exiting. Food and water should be easily accessible without requiring awkward movements. Soft, supportive bedding cushions joints during rest. Maintain comfortable temperatures, as cold may worsen joint stiffness. Ensure quiet, low-stress surroundings that promote calm rather than startling reactions that could stress joints.

Quality of life maintenance means finding ways for the rabbit to enjoy life within physical limitations. Mental stimulation remains important, so provide appropriate toys, foraging opportunities, and safe items to explore that do not require physical agility. Social needs should be met through bonded companions if appropriate or regular human interaction. Encourage gentle movement within the rabbit's comfort level, as complete inactivity promotes muscle wasting and joint stiffness. Allow activities the rabbit enjoys and can perform safely. Signs of good quality of life include appetite, engagement with environment, comfortable resting, and willingness to move about. Signs of poor quality of life include persistent pain despite treatment, loss of interest in surroundings, inability to perform basic functions, and progressive decline that cannot be reversed.

Ongoing monitoring and veterinary care ensure appropriate management throughout the rabbit's life. Schedule regular veterinary rechecks, typically every six to twelve months for stable patients, with more frequent visits if symptoms change. Report any worsening mobility, increased lameness, or changes in behavior to the veterinarian. Weight should be monitored monthly, with dietary adjustments if weight increases beyond ideal. Track any changes in medication response that might indicate progression. Radiographs may be repeated periodically to monitor for degenerative changes. Be prepared for adjustments in management as the rabbit ages or if the condition progresses.

Caregiver support helps owners maintain the commitment required for chronic condition management. Connect with rabbit owner communities for shared experiences and emotional support. The House Rabbit Society and online forums provide resources for owners of rabbits with special needs. Understand that managing chronic conditions requires ongoing commitment and may involve gradual changes in the rabbit's abilities over time. Discuss any concerns with the veterinarian openly, including quality of life questions when appropriate. Financial planning for ongoing veterinary care and medications reduces stress. Recognize that providing good care for a rabbit with patellar luxation is rewarding, allowing these animals to live happy lives despite their condition.

Dwarf rabbit breeds show the highest predisposition to patellar luxation, likely related to the genetic changes that produce the dwarf phenotype also affecting limb conformation and joint development. Netherland Dwarfs, with their compact body and short legs, are commonly affected. Holland Lops, which carry dwarf genes along with the lop ear trait, also show increased incidence. Other dwarf or small breeds including Polish, Britannia Petites, and dwarf versions of larger breeds may be predisposed. The specific genetic mechanisms linking dwarfism to patellar problems are not fully understood, but the association is clinically observed. Dwarf rabbits as a group should be monitored for orthopedic issues and evaluated by a veterinarian if any gait abnormalities are observed.

Other breeds and categories at moderate risk include rabbits with visible limb deformities of any breed, as angular leg deformities commonly accompany patellar abnormalities. Mixed breed rabbits may carry genetic predisposition from dwarf ancestry. Inbred populations of any breed may concentrate genes for skeletal abnormalities. Rabbits from sources that do not practice health screening, including many pet stores and casual breeders, may have higher rates of conformational problems including patellar luxation. Conversely, rabbits from responsible breeders who evaluate breeding stock for orthopedic soundness should have lower rates.

Screening recommendations for at-risk breeds include veterinary orthopedic evaluation as part of initial wellness examination for all dwarf breed rabbits. Breeders should have breeding stock examined and should not breed any rabbit with patellar instability. Prospective owners acquiring dwarf breeds should request health history and examine rabbits for any obvious gait abnormalities before purchase. For rescue rabbits with unknown backgrounds, thorough veterinary examination identifies existing orthopedic issues. Even rabbits without obvious symptoms may have mild patellar laxity that could progress, so familiarity with normal gait allows early detection of changes. All rabbit owners, regardless of breed, should report any gait abnormalities to their veterinarian for evaluation.

Conditions commonly co-occurring with patellar luxation include other developmental orthopedic abnormalities that reflect similar genetic or developmental processes. Angular limb deformities, where the legs are bowed or have abnormal angles, frequently accompany patellar problems as part of overall abnormal limb development. Hip dysplasia may occur in rabbits with generalized developmental joint abnormalities. Other joint laxity conditions may be present. Degenerative joint disease develops in affected stifle joints over time as a consequence of the abnormal mechanics created by patellar luxation. GI stasis is a potential secondary complication of any condition causing pain, reduced mobility, or stress, and should be watched for in any rabbit with patellar luxation, particularly during painful episodes or post-surgically.

Conditions with similar symptoms requiring differentiation from patellar luxation include other causes of hind limb lameness. Hip dysplasia or luxation causes hind limb lameness but affects the hip rather than stifle. Spinal conditions including spondylosis or intervertebral disc disease can cause hind limb dysfunction. Encephalitozoon cuniculi causes hind limb weakness through neurological effects. Stifle injuries including cruciate ligament rupture cause acute stifle dysfunction. Infectious arthritis affects any joint including the stifle. Trauma and fractures cause acute lameness. Physical examination with palpation of the stifle identifies patellar instability, and imaging confirms the diagnosis and rules out other conditions. Multiple conditions may coexist in the same rabbit.

Potential complications of patellar luxation primarily involve progressive degenerative changes and associated dysfunction. Osteoarthritis develops in the affected stifle as abnormal mechanics cause cartilage wear, creating progressive pain and stiffness. Muscle atrophy in the affected limb worsens over time if the rabbit does not use the leg normally. Bilateral involvement can severely compromise the rabbit's ability to hop, groom, and consume cecotropes. If the rabbit cannot reach cecotropes, malnutrition from inability to consume these essential nutrient sources occurs. GI stasis may develop if pain and immobility reduce eating. Obesity from reduced activity worsens joint stress. Prevention of complications involves appropriate treatment of the patellar luxation itself, weight management, environmental modification, and close monitoring with early intervention for any developing problems.