MPL Surgery for Dogs
Medial Patellar Luxation Repair — Correcting a Slipping Kneecap
Antietam Valley Animal Hospital | Berks County, PA | Reading, PA
Understanding Medial Patellar Luxation (MPL)
The patella (kneecap) normally glides up and down within a groove at the end of the femur (the trochlear groove) as the knee bends and straightens. In medial patellar luxation, the kneecap slips out of that groove toward the inside of the leg, which is why it's called “medial” luxation — the most common direction in dogs. This is usually a developmental (congenital) issue related to the alignment of the leg bones, and it's especially common in small and toy breeds, though it occurs in dogs of any size.
MPL is graded on a scale of 1 to 4 based on severity:
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Grade 1: The kneecap can be manually luxated but returns to place on its own — often not causing noticeable lameness
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Grade 2: The kneecap luxates during normal activity and may stay out until manually or spontaneously repositioned — often causes an intermittent “skipping” gait
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Grade 3: The kneecap is luxated most of the time but can be manually repositioned
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Grade 4: The kneecap is permanently luxated and cannot be manually repositioned, often with a visibly bowed leg
Surgery is generally recommended for dogs with clinical signs (lameness, skipping, discomfort) at Grade 2 and above, since a chronically unstable kneecap leads to progressive cartilage wear, arthritis, and increased strain on the CCL over time.
What Does MPL Surgery Involve?
Because MPL is caused by a combination of anatomical factors, correction typically combines two or three techniques in the same surgery, tailored to your dog's specific anatomy:
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Trochlear groove deepening — the groove the kneecap rides in is deepened so it tracks properly and is less prone to slipping out.
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Tibial tuberosity transposition (TTT) — the bony attachment point of the patellar tendon on the tibia is cut and repositioned to properly align the pull of the quadriceps muscle with the kneecap and groove, then secured with a small pin and/or wire.
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Soft tissue reconstruction — the joint capsule and surrounding soft tissue are tightened on the loose side and released on the tight side to help hold the kneecap in correct position.
In more severe or long-standing cases, or in dogs with significant bowing of the leg bones, additional corrective procedures may be recommended — we'll explain exactly what your dog's case requires at your consultation.
Preparing for Surgery
Required Pre-Operative Workup
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Orthopedic exam to grade the luxation and assess for concurrent CCL instability, which occurs more frequently in dogs with chronic MPL
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Radiographs (X-rays) of the knee and, often, the full hind limb to assess bone alignment and plan the surgical correction
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Pre-anesthetic bloodwork (CBC and chemistry panel)
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Weight check and physical exam the morning of surgery
Preparing Your Home Before Surgery Day
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A confinement space — crate, gated room, or small area with minimal stairs
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Rubber-backed rugs or yoga mats over slick flooring, especially important for small-breed patients
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A sling or towel for support on walks and stairs (even for small dogs, extra support helps in the first days)
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An e-collar or recovery suit on hand
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A plan for short, controlled leash walks for bathroom breaks only
The Day Before Surgery
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No food after 8pm the night before; water is generally fine until the morning
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Bathe your dog if needed — the incision can't get wet for at least 10–14 days
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Confirm your confinement area and rugs are set up
Surgery Day
Your dog is admitted in the morning for a pre-anesthetic exam, then placed under general anesthesia with continuous monitoring throughout. The surgeon performs the specific combination of corrective techniques planned for your dog's anatomy, then closes the incision in layers.
We use a layered ("multimodal") anesthesia and pain-control protocol for every orthopedic surgery, designed to keep your dog calm and comfortable at every stage and to stay ahead of pain rather than catching up to it. Before surgery, your dog receives a combination of a calming sedative and pain-relieving medications (dexmedetomidine, midazolam, and methadone) to ease anxiety and provide the first layer of pain relief before anesthesia even begins. Anesthesia is then induced gently with propofol and maintained during surgery with isoflurane gas -- a well-established, closely monitored combination used in veterinary and human hospitals alike. Throughout the procedure, a dedicated team member continuously monitors your dog's heart rate, blood pressure, oxygen levels, and body temperature. At the surgical site, we use Nocita, a long-acting local anesthetic that numbs the area for up to 72 hours after surgery -- similar to a nerve block a person might receive after their own orthopedic surgery -- which meaningfully reduces how much pain your dog feels as they wake up and in the days that follow. We also give an anti-inflammatory pain medication (carprofen) during surgery to start reducing pain and swelling right away, and send you home with carprofen, gabapentin (a nerve pain medication), and an antibiotic to keep your dog comfortable and support healing over the following days and weeks.
Anesthesia and Pain Management
The First 12 Hours: Going Home (Outpatient Recovery)
As a general practice, we don't have overnight staffing on-site, so all of our surgical patients — including amputations — go home with their owners the same day, once they're comfortable, stable, and recovered enough from anesthesia to travel. In our experience, most pets do just as well, and often better, resting overnight in the comfort of home with their own family rather than in a hospital kennel, as long as you follow the aftercare instructions below closely. In the rare case that a pet needs a higher level of overnight monitoring than we can provide, we'll coordinate a direct transfer to a 24-hour emergency/specialty hospital such as BluePearl Pet Hospital in Wyomissing or Metropolitan Veterinary Associates, and stay in close contact with both their team and you throughout.
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Grogginess from anesthesia and pain medication for several hours — keep confined and supervised, especially important for small dogs who may try to jump off furniture
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First walk: short, leash-controlled bathroom breaks only, with support if needed
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Icing the knee for 10–15 minutes, 2–3 times the first evening
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Pain medication given exactly as prescribed and on schedule
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A reduced appetite the first evening is common; report a dog not eating or drinking at all by the next morning
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Mild swelling, bruising, and a small amount of clear or blood-tinged discharge is normal for the first few days
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Overnight confinement so your dog can't jump, slip, or attempt stairs unsupervised
Recheck Appointments & Healing Timeline
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14 days post-op: Suture/staple removal and incision check.
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6 weeks post-op: Recheck radiographs to confirm the tibial tuberosity transposition (if performed) has healed properly.
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3–4 months post-op: Full activity clearance for most dogs.
Home Rehabilitation Program
Weeks 0–2: Foundation Phase
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Strict confinement between exercise sessions
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Passive range of motion (PROM) and gentle massage 2–3 times daily once cleared
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Short, slow, leash-controlled walks for bathroom purposes only
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Ice therapy after activity; gentle heat to the surrounding muscles can begin around day 4
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E-collar worn at all times to prevent licking
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No jumping, off-leash activity, unsupervised stairs, or play with other dogs — particularly important for small breeds who tend to want to jump on and off furniture
Weeks 3–10: Strength & Balance Phase
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Longer, varied controlled leash walks — figure-8 patterns, gentle inclines, stepping over low obstacles
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Weight-shifting and three-legged standing exercises
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Sit-to-stand “doggy squats” and cookie stretches
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Controlled wading in water once sutures are removed
Months 3–4: Return to Normal Activity
With good healing confirmed on recheck films and consistent, confident use of the leg, most dogs return to normal activity — including jumping on and off furniture, if allowed in your household — by 3–4 months.
Incision Care: What's Normal vs. What Needs a Call
Normal
• Mild swelling and bruising for the first week
• A small amount of clear or blood-tinged discharge for the first few days only
• Mild discomfort and warmth around the leg
Contact Us Right Away If You Notice
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Swelling that lasts longer than a week, or any swelling around the knee itself
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Large amounts of discharge or active bleeding
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Discharge that is white, green, or thick/sticky
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A return of the “skipping” gait that was present before surgery, which could indicate the kneecap is luxating again
Frequently Asked Questions
How much does MPL surgery cost?
Pricing depends on the severity (grade) of the luxation and your dog's weight: Grade II–III MPL is $2,500 for dogs up to 80 lbs ($2,900 over 80 lbs), and Grade IV MPL — which typically needs more extensive correction — is $3,000 for dogs up to 80 lbs ($3,400 over 80 lbs). This includes pre-operative examination, anesthesia, surgery, pain management, and recovery/nursing care. Rechecks are included; follow-up radiographs/sedation are at an additional cost. If both knees need surgery, we'll walk you through pricing for staged versus same-day bilateral surgery at your consultation.
Does my dog need both knees done?
MPL is bilateral (affects both knees) in a large proportion of small-breed dogs, though severity often differs between the two sides. We'll assess both knees at your consultation and let you know if surgery is recommended on one or both, and whether we'd stage the surgeries or do them at the same time.
Will my dog need surgery again in the future?
Most dogs do very well long-term after MPL correction. Recurrence is possible, particularly in more severe (Grade 3–4) cases or dogs with significant bone deformity, which is part of why an accurate initial grading and thorough surgical plan matters.
How long until my dog walks normally again?
Many small-breed dogs show good weight-bearing within 1–2 weeks, with continued improvement over 6–12 weeks as the bone and soft tissue fully heal.
Will my dog need to stay overnight after surgery?
No. As a general practice, we don't have overnight staffing on-site, so all of our surgical patients go home with their owners the same day. In our experience, most dogs recover just as well, and often more comfortably, resting at home with their family than they would in a hospital kennel overnight. On the rare occasion a pet needs a higher level of overnight monitoring, we'll arrange a direct transfer to a 24-hour facility such as BluePearl Pet Hospital in Wyomissing or Metropolitan Veterinary Associates.
Can I do this surgery at your general practice instead of a referral hospital?
Yes. Dr. Lee and our surgical team perform MPL correction in-house. As a general practice rather than a large corporate referral center, we're able to offer this level of orthopedic care with less overhead, which often makes it more accessible for families, without cutting corners on anesthesia monitoring or aftercare.
What if my dog doesn't seem to be improving?
Contact us any time during recovery. If your dog plateaus, regresses, or you're simply unsure whether something is normal, we'd rather hear from you early.