Reviewed by: Dr. David Allman, DVM, DACVS-SA | Surgical Director, VROC
If your veterinarian has diagnosed your dog with a luxating patella, one of the most important questions is whether the condition is mild enough to monitor or whether it is beginning to affect the knee in a way that warrants surgical correction.Mild luxations that cause little or no lameness may be monitored over time. But when the kneecap repeatedly slips out of position, causes persistent lameness or discomfort, affects normal movement, or is associated with progressive changes in limb alignment, surgery becomes an important consideration.Because patellar luxation can progress differently from one dog to another, understanding when to move from observation to surgical evaluation is key to protecting long-term comfort and function.
At a glance
Mild patellar luxation without lameness may only require monitoring. Surgery becomes more likely when luxation causes recurrent skipping or limping, progresses over time, or is associated with higher grades and abnormalities in limb alignment. A specialist orthopedic evaluation can determine whether surgical correction is appropriate.
What Is a Luxating Patella?
The patella is the kneecap, a small bone that normally tracks within a groove at the end of the thigh bone, or femur, as your dog bends and straightens the knee. A luxating patella is a kneecap that moves out of that groove.In small dogs, the patella most commonly moves toward the inside of the leg, called medial patellar luxation, or MPL. Lateral patellar luxation, where the kneecap moves toward the outside, can also occur but is less common.Many owners first notice a quick “skip” or hop in the back leg. A dog may briefly hold the leg up, take a few steps, and then return to walking normally once the patella moves back into place. Other dogs may show more persistent lameness, while mild cases can be discovered during a routine physical examination.If skipping becomes more frequent, develops into persistent limping, or begins to limit normal activity, it is worth having the knee reevaluated rather than assuming the condition remains mild.
Why Are Small Dogs More Prone to Patellar Luxation?
Patellar luxation is a common orthopedic condition in dogs and is seen particularly often in small and toy breeds.In most affected small dogs, the condition is developmental rather than the result of a single injury. Differences in the alignment of the bones and soft tissues of the hind limb can change the direction in which the kneecap is pulled as the dog moves. These may include a shallow femoral groove, altered alignment or rotation of the femur or tibia, or soft tissue imbalance around the knee.Over time, repeated abnormal movement of the patella can contribute to cartilage wear and degenerative changes within the joint. Some dogs may also have other orthopedic conditions affecting the same knee, including cranial cruciate ligament disease.
Understanding Patellar Luxation Grades
Veterinarians classify patellar luxation on a scale from Grade 1 to Grade 4. The grade describes how easily the patella luxates and whether it returns to its normal position.
Grade 1:The kneecap normally remains in its groove. A veterinarian can manually push it out of position during an examination, but it returns on its own. Clinical signs are often mild or absent.
Grade 2:The kneecap moves out of position intermittently and may remain luxated temporarily before returning to the groove. Dogs may show occasional skipping or intermittent lameness. Some remain comfortable for long periods, while others develop increasingly frequent symptoms.
Grade 3:The kneecap remains outside the groove most of the time. It can usually be manually returned to position but tends to luxate again. Lameness and abnormalities in limb alignment are more commonly present.
Grade 4:The kneecap is permanently luxated and cannot be manually returned to its normal position. Dogs may develop substantial changes in limb alignment and a persistently flexed or crouched posture.
When Patellar Luxation Requires Surgical Evaluation
The grade is important, but it is not the only factor that determines whether surgery is appropriate.Mild luxations that are not causing clinical signs can often be monitored, particularly in Grade 1 and some minimally symptomatic Grade 2 cases. Weight management, appropriate exercise, rehabilitation, and medications when needed may help support comfort, but conservative care does not correct the underlying mechanics of the knee.When luxation becomes recurrent or persistent, causes lameness, interferes with normal activity, or is associated with progressive abnormalities in limb alignment, surgical correction becomes more strongly indicated. Higher-grade luxations are also more likely to require surgery because the patella remains displaced more consistently and the mechanical abnormalities affecting the limb are often more pronounced.In these cases, delaying evaluation may allow abnormal patellar tracking, cartilage wear, and skeletal changes to continue.
The goal of orthopedic surgeryis not simply to place the kneecap back into its groove. It is to correct the mechanical factors preventing normal tracking and restore the best possible alignment and function of the limb.
What Does an Orthopedic Surgeon Consider Before Recommending Surgery?
Two dogs can have the same patellar luxation grade and still require different treatment plans.During an orthopedic evaluation, the surgeon considers several factors together:
How often the patella luxates
Whether it is causing pain or lameness
Whether clinical signs are progressing
Whether the patella can be returned to its normal position
The depth and shape of the femoral groove
The alignment and rotation of the femur and tibia
The direction of pull through the quadriceps mechanism
The presence of arthritis or other joint changes
Whether other orthopedic disease, including cruciate ligament disease, is present
Imaging may also be used to better understand the anatomy and degree of skeletal deformity, particularly in more complex cases.
For dogs with recurrent lameness, higher-grade luxation, or suspected skeletal deformity, evaluation by a board-certified veterinary surgeoncan help define the full mechanical problem and determine which combination of surgical techniques is most appropriate.
What Does Patellar Luxation Surgery Involve?
There is no single surgical procedure appropriate for every dog with patellar luxation. Depending on the dog’s anatomy, a surgeon may combine several techniques.A trochleoplasty deepens or reshapes the femoral groove to improve how the patella sits and tracks within it. A tibial tuberosity transposition repositions the bony attachment of the patellar tendon to improve alignment of the quadriceps mechanism. Soft tissue balancing procedures may also help restore normal tracking.In dogs with more substantial femoral or tibial deformity, corrective bone surgery may be required to restore more normal limb alignment.
At VROC, patellar luxation correction is performed by board-certified surgeonsin a surgeon-owned hospital dedicated exclusively to orthopedic and spine care. This specialized focus allows each surgical plan to be built around the individual patient’s anatomy, degree of luxation, limb alignment, and long-term functional needs.
What Does Recovery Look Like?
Dogs typically require a period of restricted activity and controlled leash walking while the surgical repair heals. Activity is then gradually increased, with physical rehabilitationoften incorporated to help restore strength, range of motion, and normal use of the limb.Most dogs can achieve good function following appropriate surgical correction, but outcomes depend on factors including the severity of the luxation, skeletal deformity, existing joint damage, and concurrent orthopedic disease. Your surgeon will provide an individualized recovery plan based on your dog’s condition and the procedures performed.
Frequently Asked Questions
Does a luxating patella always need surgery?
No. Mild luxations that are not causing pain, lameness, or functional problems can often be monitored. Surgery is more commonly considered when luxation is symptomatic, progressive, or associated with significant abnormalities in limb mechanics or alignment.
What grade of luxating patella usually needs surgery?
Surgery is most often considered for Grade 2 and higher luxations, but grade alone does not determine treatment. Some Grade 2 dogs remain comfortable with monitoring, while progressive Grade 2 cases and Grade 3 or Grade 4 luxations are more likely to require surgical correction.
Can a dog live with a luxating patella without surgery?
Yes. Some dogs with mild, low-grade luxation remain comfortable without surgery. Regular veterinary examinations are important because the frequency of luxation and clinical signs can change over time.
What happens if a luxating patella is left untreated?
A mild, asymptomatic luxation may remain stable. Repeated or persistent abnormal movement of the patella, however, can contribute to cartilage wear, arthritis, progressive lameness, and changes in the mechanics of the knee. Progressive or symptomatic cases should be reevaluated to determine whether surgical correction is indicated.
What is recovery like after luxating patella surgery?
Recovery typically involves restricted activity followed by a gradual, controlled return to movement. The timeline depends on the severity of the luxation and the procedures required, and physical rehabilitation may form part of the recovery plan.
Expert Patellar Luxation Care for Dogs in Austin
Not every luxating patella requires surgery, but progressive or symptomatic cases should not simply be left to worsen.
VROC, Veterinary Regional Orthopedic Center, is a surgeon-owned hospital dedicated exclusively to orthopedic surgeryand spine care for dogs and cats across Austin and Central Texas. For dogs with recurrent lameness, higher-grade luxation, or significant limb deformity, a focused orthopedic evaluation can help determine whether surgical correction offers the best opportunity to restore more normal knee mechanics and support long-term function.
If your dog is skipping more frequently, limping, becoming less active, or showing signs of discomfort, request a consultation with VROCor speak with your primary veterinarian about referral for an orthopedic evaluation.
Referring veterinarians: VROC welcomes referrals for evaluation and surgical management of patellar luxation, including progressive, higher-grade, and anatomically complex cases. Make a referralto partner with our surgical team on your patient’s care.
