TPLO (Tibial Plateau Leveling Osteotomy) surgery is one of the most common and successful procedures performed to stabilize the knee after a cranial cruciate ligament (CCL) tear in dogs.

While many pet parents expect their dog to immediately stop limping after surgery, recovery is a gradual healing process. It requires structure, careful activity restriction, and close adherence to surgical recommendations to achieve the best long-term outcome.

At SustainableVet, we emphasize that recovery is just as important as the surgery itself. The goal after TPLO surgery is not simply to get your dog walking quickly. It is to allow the bone and soft tissues to heal properly while safely rebuilding strength, comfort, and confidence in the limb.

When Can a Dog Start Walking After TPLO Surgery?

One of the most common questions after surgery is how soon dogs can walk again. The short answer: dogs are encouraged to begin controlled limb use early in recovery, but activity must remain extremely restricted while the bone heals.

We want your dog to use the operated leg, but not overuse it.

Most dogs will begin toe-touching on the operated leg within the first several days after surgery. Limping is expected during the early recovery period. What we want to see is gradual improvement over time:

• More consistent weight bearing
• Improvement in muscle mass
• Improved comfort during controlled, regimented leash walks

While early limb use is encouraging, it is crucial to understand that the bone itself is still healing internally. That process typically takes 8 to 12 weeks.

TPLO Recovery Timeline at a Glance

Indoor Recovery: 8 to 12 Weeks

During the entire recovery, exercise restriction is critical. Crate confinement or restriction to a small area with good traction is strongly recommended. Most dogs will slip and slide on hardwood floors and can easily injure themselves inside the house when not confined.

Days 1 to 10: Initial Rest Period

During the first 7 to 10 days after surgery, walking is restricted to short, slow leash walks only for bathroom breaks. These walks should be calm, controlled, and limited to what is necessary.

Days 10 to 14: First Recheck Appointment

By the first recheck appointment, many dogs are partially weight-bearing during a controlled, slow walk.

At this stage, your veterinary team will evaluate the incision, swelling, comfort level, and early limb use. Even if your dog is doing well, activity should still remain very restricted.

Weeks 2 to 8: Gradual Activity Increase

As healing progresses, 10 to 15 minute leash walks may be introduced to build more strength, reduce stiffness, and encourage bony healing without overloading the leg.

Walking activity and physical therapy are gradually increased according to your surgeon's recommendations. This stage is not about testing how much your dog can do. It is about safely rebuilding muscle mass while protecting the healing bone.

Weeks 8 to 12: Final Healing and Recheck

At the final recheck appointment, radiographs (X-rays) are typically performed to assess bone healing.

By this stage, many dogs have minimal or no lameness during controlled activity. If the osteotomy has healed adequately, your surgeon may recommend a gradual transition back toward more normal activity.

Why Strict Rest Is Required After TPLO: The Mechanics

During a TPLO procedure, a precise geometric cut is made in the tibia. The bone is then rotated into a new position and stabilized using a specialized metal plate and screws.

Until the bone heals, the plate and screws are responsible for maintaining the new bone position and protecting the osteotomy during normal controlled movement.

Excessive activity, slipping, jumping, or twisting too early can place forces on the repair that it is not yet ready to tolerate.

Even if your dog appears comfortable and eager to do more, unrestricted activity too early can create significant complications before the bone has fully healed.

Recovery after TPLO surgery is truly a situation where slow and steady wins the race.

Factors That Affect TPLO Walking Recovery Time

Recovery time depends on several individual factors. These influence how quickly walking progresses and how carefully activity must be advanced.

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Postoperative Care

Strict environmental management, appropriate pain control, and structured rehabilitation directly support a safer recovery. This includes using a leash at all times outdoors, preventing stairs and jumping, keeping floors non-slip, and following medication and activity instructions closely.

Presence of Complications

Issues such as incision problems, infection, implant failure, delayed bone healing, or fracture can extend the recovery timeline and delay walking progression.

Any sudden worsening in lameness, swelling, pain, or reluctance to use the limb should be reported to your veterinary team immediately.

How to Safely Support Your Dog's Mobility During Recovery

A structured support plan improves long-term outcomes and reduces the risk of setbacks.

Use a Short Leash and Harness at All Times

All walks during recovery must remain on a short leash with a slow, controlled pace. A harness can help control movement and prevent sudden lunging or twisting.

Your dog should not be allowed to run ahead, play, greet other dogs energetically, or move unpredictably during recovery walks.

Stick to Strict Exercise Limits

Follow your veterinarian's recommended walking times and avoid any off-leash activity, running, jumping, or rough play.

Many complications occur not because a dog was walking, but because the dog suddenly slipped, jumped, twisted, or did too much too soon.

Prioritize Pain Management

Administer all prescribed pain medications on schedule. Good pain control keeps your dog comfortable and encourages more even, controlled weight-bearing during brief walks.

Do not stop medications early unless your veterinarian advises you to do so.

Incorporate Professional Physical Therapy

Gentle range-of-motion exercises may help reduce stiffness early in recovery. As healing permits, rehabilitation options such as controlled strengthening exercises, hydrotherapy, or underwater treadmill sessions may help rebuild muscle while reducing stress on the limb.

Working with a certified canine rehabilitation specialist allows for a customized plan that helps restore joint flexibility, rebuild muscle, improve comfort, and support a safe return to normal mobility.

Risks of Walking Too Soon or Too Much After TPLO Surgery

Being cautious protects the surgical repair. Allowing your dog to run, jump, slip, or play too early carries real clinical risks.

Implant Strain or Failure

Excessive weight-bearing, sudden twisting, or impact forces too early can place abnormal stress on the plate and screws. In severe cases, implants can loosen or fail, requiring additional treatment or corrective surgery.

Delayed Bone Healing

Too much motion or repeated stress at the surgical site can slow the bone's ability to heal properly, prolonging the total recovery period.

Increased Pain and Inflammation

Overexertion can cause swelling, soreness, and joint inflammation. This may make your dog less willing to use the leg and can delay functional recovery.

Setbacks in Recovery

Too much activity too soon can cause limping, soft tissue irritation, swelling around the surgical site, or a slower return to comfortable walking. In some cases, setbacks require a longer rehabilitation plan or additional veterinary care.

Frequently Asked Questions

How long should my dog be confined after TPLO surgery?

Your dog needs indoor confinement for the entire two to three months of recovery. Confinement prevents accidental running, jumping, and rough movement.

Can I let my dog run or jump after TPLO surgery?

No. Running, jumping, stair use, and off-leash activity are restricted for approximately 8 to 12 weeks. The exact timeline depends on your dog's healing and X-ray findings.

What signs show my dog is recovering well and ready for longer walks?

Positive signs include reduced swelling, steady comfort levels, consistent toe-touching, and gradual improvement in walking quality. Always confirm with your veterinary team before increasing walk duration.

Is physical therapy necessary after TPLO surgery?

Some dogs recover well with structured home care alone, but physical therapy is always an excellent adjunct to build muscle strength and improve use of the operated leg.

When can my dog return to full, normal activity?

Most dogs achieve adequate bone and soft tissue healing between 8 and 12 weeks after surgery. Full activity should only resume gradually after follow-up X-rays confirm the osteotomy has healed and your surgeon provides formal approval.

Final Thoughts

Dogs are often ready to do more before their bone is ready to tolerate more. Dogs will not moderate their own activity. That is why TPLO recovery requires a balance between early controlled limb use and strict protection of the surgical repair.

With appropriate rest, controlled leash activity, pain management, follow-up care, and rehabilitation when needed, most dogs return to comfortable, active lives after TPLO surgery.

About this Collaboration: Successful healing happens both inside and outside the operating room. This article combines structured veterinary rehabilitation guidelines with direct clinical insights from veterinary orthopedic surgeons to support pet parents through every stage of the recovery journey.

Understanding TPLO Surgery and Why It’s Needed

Tibial Plateau Leveling Osteotomy (TPLO) is a surgical procedure used to repair a torn cranial cruciate ligament (CCL) in dogs — a common injury that causes pain and hind limb instability. The surgery reshapes the tibia bone to restore stable joint movement without depending on the damaged ligament.

• Purpose of TPLO Surgery: Recommended for active or large-breed dogs where conservative treatments cannot restore function.
• Recovery Period: Most dogs need 8–12 weeks for bone healing, followed by controlled physical therapy for full recovery.
• Cost Overview: TPLO surgery is one of the more expensive orthopedic procedures, often ranging from $3,000 to $6,000 depending on clinic and location.

Understanding these basics sets the stage for evaluating insurance coverage options.

Average Cost of TPLO Surgery for Dogs

TPLO surgery is a complex orthopedic procedure, and its cost varies widely based on case difficulty, hospital standards, and regional pricing. Understanding the range helps owners plan financially before exploring insurance options.

• National Cost Range: In the U.S., TPLO surgery typically costs between $3,000 and $6,000 for a single leg. In some specialty hospitals or metropolitan areas, costs can exceed $7,000, especially for large breeds.
• Simple vs. Complex Cases: Minor ligament tears with minimal complications are less costly, while complex fractures, bilateral surgeries, or infections increase total expenses significantly.
• Influence of Dog Size: Larger dogs require stronger plates, longer anesthesia, and extended recovery monitoring, leading to higher bills.
• Hospital and Surgeon Type: Referral centers and board-certified surgeons charge more due to specialized equipment and experience.
• Follow-Up and Rehabilitation: Post-surgical care, including X-rays and physiotherapy, can add $500–$1,500.

Because of these high expenses, many pet owners consider insurance coverage essential to make TPLO surgery affordable without compromising care quality.

Does Pet Insurance Cover TPLO Surgery?

Most modern pet insurance plans do cover TPLO surgery, but eligibility depends on policy terms and your dog’s medical history. The key factor is whether the cruciate ligament injury is considered pre-existing.

• General Coverage Rule: If your dog’s CCL injury occurs after the waiting period and is not pre-existing, TPLO surgery is usually included under accident or illness coverage.
• Waiting Periods: Many insurers enforce a 6–12 month waiting period for cruciate ligament coverage to prevent claims on undiagnosed injuries.
• Plan Type Differences: Comprehensive plans with illness and injury coverage are most likely to include TPLO, while accident-only policies may exclude it.
• Common Exclusions: Some policies do not cover congenital joint disorders or prior CCL injuries in the opposite leg.
• Importance of Documentation: Detailed veterinary records proving the injury is new are often required for claim approval.

In most cases, TPLO is covered when the policy is active before the injury, making early insurance enrollment a smart preventive decision.

How Pre-Existing Conditions Affect TPLO Coverage

Pre-existing conditions are the most common reason pet insurance denies TPLO-related claims. Understanding what qualifies as “pre-existing” helps you protect your dog’s future eligibility.

• Definition of Pre-Existing Conditions: Any medical issue diagnosed or showing symptoms before policy activation or during the waiting period is considered pre-existing.
• Prior Cruciate Ligament Injuries: If your dog previously tore a CCL or ACL in either leg, many insurers exclude future coverage for both knees under a bilateral condition clause.
• Breed Predisposition: Large or active breeds prone to ligament tears may face stricter review before approval.
• Importance of Early Enrollment: Getting insurance while your dog is young and injury-free ensures eligibility for full cruciate coverage later in life.
• Proof of Clean Health Record: Regular vet visits and medical documentation help verify no pre-existing issues existed at policy start.

Early planning and transparent medical history are crucial for securing TPLO coverage when unexpected injuries occur.

What Pet Insurance Typically Covers for TPLO Surgery

When TPLO surgery is approved under your insurance, most plans cover a wide range of medical services related to diagnosis, treatment, and recovery. This support can significantly reduce financial stress.

• Diagnostic Imaging: X-rays, CT scans, or MRIs used to confirm ligament rupture are usually included in coverage.
• Surgery and Hospitalization: The main surgical procedure, anesthesia, and hospitalization costs are covered up to policy limits.
• Post-Surgery Medications: Pain relievers, antibiotics, and anti-inflammatories prescribed during recovery are typically reimbursable.
• Physical Therapy: Many plans include hydrotherapy or physiotherapy sessions for rehabilitation under extended recovery benefits.
• Follow-Up Visits and Complications: Recheck exams, wound care, or treatment of infections that occur after surgery are generally included within your policy’s time and cost caps.

Comprehensive coverage ensures your dog’s TPLO treatment is managed safely from diagnosis through recovery, minimizing both physical and financial strain.

What’s Not Covered by Pet Insurance for TPLO Surgery

Even though many pet insurance plans include TPLO coverage, certain conditions and costs fall outside standard policies. Knowing these exclusions helps prevent surprises during reimbursement.

• Pre-Existing Injuries: If your dog showed signs of a cruciate tear before enrollment or during the waiting period, TPLO surgery won’t be covered.
• Bilateral Exclusion Clauses: Some insurers exclude the second knee once one cruciate injury occurs, even if it happens years later.
• Preventive or Elective Procedures: Pre-surgical screenings, optional rehab sessions, or supplements are often excluded from reimbursement.
• Rehabilitation Limits: Physiotherapy or hydrotherapy may only be covered for a set number of weeks or up to a cost cap.
• Deductibles and Co-Pays: Owners are responsible for annual deductibles, coinsurance percentages, and any charges beyond policy limits.
• Waiting Period Restrictions: Claims made before the orthopedic waiting period ends are automatically denied.

Understanding these exclusions helps you plan better and choose insurance that aligns with your dog’s long-term orthopedic needs.

Best Pet Insurance Providers That Cover TPLO Surgery

Several leading pet insurance companies offer coverage for TPLO surgery, but each has unique rules for cruciate ligament injuries. Comparing policies ensures you find the best fit for your dog’s medical and financial needs.

• Healthy Paws: Covers TPLO if the injury occurs after enrollment and the waiting period. Offers unlimited annual payouts but no coverage for pre-existing conditions.
• Trupanion: Known for 90% reimbursement on eligible costs and direct vet payments, but has a 30-day waiting period for orthopedic claims.
• Embrace: Includes TPLO surgery under illness coverage, with the option to reduce or waive the orthopedic waiting period through a vet exam.
• Spot and Fetch: Both cover cruciate ligament injuries after the waiting period, with flexible reimbursement and deductible options.
• ASPCA Pet Health Insurance: Offers comprehensive coverage but applies a 14-day illness waiting period for orthopedic procedures.

Selecting a provider with transparent cruciate coverage and high reimbursement rates ensures better financial protection for major surgeries like TPLO.

How to File a TPLO Surgery Claim

Filing a TPLO surgery claim correctly helps speed up reimbursement and avoids processing delays. Most insurers require detailed veterinary documentation and itemized invoices.

• Collect Required Documents: Obtain a full medical report, diagnostic imaging results, itemized invoices, and proof of payment from your veterinarian.
• Submit Through the Portal: Most insurance providers allow online submissions through their official portals or mobile apps for faster review.
• Attach Medical History: Include your dog’s previous health records to confirm the cruciate injury isn’t pre-existing.
• Timeline for Reimbursement: Claims are typically processed within 10–15 business days, though some complex cases may take longer.
• Follow Up Promptly: Contact your insurer if documentation requests arise or delays occur. Keeping communication open prevents claim rejection.
• Save Copies: Always keep digital or printed copies of every document for future claims.

Timely, organized submission of records ensures smoother claim approval and quicker financial relief after TPLO surgery.

Tips for Choosing the Right Pet Insurance for Orthopedic Coverage

Choosing the right insurance plan can make a major difference in managing expensive orthopedic procedures like TPLO surgery. Understanding policy details beforehand prevents financial stress later.

• Avoid Bilateral Exclusions: Choose insurers that cover both knees even if one is previously injured. This is critical for breeds prone to cruciate tears.
• Check Waiting Periods: Some plans have 6–12 month orthopedic waiting periods. Early enrollment ensures coverage is active when needed.
• Customizable Reimbursement Options: Plans allowing flexible deductibles and payout percentages help control monthly premiums.
• Understand Policy Limits: Review annual and lifetime caps to ensure coverage remains adequate for long-term orthopedic care.
• Read Fine Print Carefully: Always confirm whether physical therapy, imaging, and post-surgical complications are included.
• Ask About Direct Payments: Some insurers pay veterinarians directly, saving you from covering full costs upfront.

Selecting a policy that combines comprehensive coverage with transparency ensures peace of mind when facing orthopedic surgeries like TPLO.

Conclusion

TPLO surgery is one of the costliest orthopedic procedures for dogs, making strong insurance coverage essential. While most insurers cover the operation for non-pre-existing injuries, exclusions and waiting periods can greatly affect eligibility.

• Coverage Essentials: Understand plan inclusions, orthopedic waiting times, and bilateral condition policies.
• Early Enrollment: Starting coverage before injuries occur ensures full eligibility for TPLO claims.
• Policy Comparison: Review reimbursement rates, deductibles, and annual caps to choose the best protection for your dog’s long-term health.
• Consultation: Discuss all coverage details with your insurer before scheduling surgery to avoid claim denial or hidden costs.

With the right pet insurance plan and proper timing, you can manage TPLO expenses confidently while securing the best surgical outcome for your dog.

FAQs

Will insurance cover both legs if both cruciate ligaments tear?

Most pet insurance plans cover both legs only if the policy doesn’t include a bilateral exclusion clause. Some insurers consider cruciate injuries as linked conditions, meaning if one leg tears before enrollment, the other may not be covered. Always confirm your insurer’s bilateral coverage terms in writing before surgery.

Can I get coverage if my dog already tore one ligament?

If your dog had a previous cruciate ligament injury before the policy began, most insurers will treat future TPLO claims as pre-existing and deny coverage. However, enrolling early or choosing a plan without bilateral exclusions ensures future injuries can still qualify for reimbursement.

How long is the waiting period for TPLO coverage?

Orthopedic waiting periods vary by provider, typically ranging from 6 to 12 months after policy activation. Some companies allow a vet exam waiver to shorten this period. Starting insurance early ensures your dog’s coverage is active before any ligament injury occurs.

What if my dog needs a second TPLO later?

If both legs require TPLO surgery and your policy includes bilateral coverage, the second operation is usually covered as long as it occurs after the waiting period. Keep consistent records and ensure premiums remain active to avoid claim rejection for the second procedure.

Which pet insurance companies cover TPLO the best?

Top-rated providers for TPLO coverage include Trupanion, Embrace, Healthy Paws, and Fetch. These plans typically offer 80–90% reimbursement on approved orthopedic claims with clear terms for cruciate ligament injuries. Always compare waiting periods, bilateral rules, and annual payout limits before finalizing your plan.

CCL rupture in dogs is not the same injury as ACL rupture in humans.

In humans, the anterior cruciate ligament typically tears during sudden trauma a pivoting fall on a ski slope, a tackle on a football field.

In dogs, the same ligament almost always fails through slow, progressive degeneration that began months or years before the day the dog comes in lame.

Understanding why the canine CCL fails and which dogs are most at risk is essential for prevention strategies and for recognizing early warning signs.

Quick answer: The canine CCL fails through progressive degeneration, not sudden trauma. Key risk factors are breed, obesity, poor fitness, tibial slope, and genetics. At least 50% of dogs that rupture one CCL will rupture the other within 1 to 2 years.

Key takeaways

• CCL rupture results from degeneration, not trauma: ACVS confirms slow, progressive degeneration rather than acute injury to a healthy ligament
• Obesity is the most modifiable risk factor: excess weight increases compressive and shear forces on the CCL with every step
• High-risk breeds include Labrador, Rottweiler, Newfoundland, Mastiff, and Akita: genetic inheritance has been demonstrated in Newfoundlands and Labradors
• Partial tears almost always progress to complete rupture: ACVS confirms this and notes progression is the rule, not the exception
• At least 50% of dogs rupture the opposite CCL within 1 to 2 years of the first rupture
• Neuter status increases CCL risk: spayed and neutered dogs show higher rates in multiple studies

Why dog CCL disease differs from human ACL injury

Colorado State University: "In humans, trauma (such as skiing, football, or soccer injuries) is the most common reason for injury of the ACL.

This 'traumatic' rupture can happen in dogs but is quite rare."

CSU: "Most commonly, CCLD is caused by a combination of many factors, including aging of the ligament (degeneration), obesity, poor physical condition, conformation, and breed."

In humans, a healthy ACL tears from a single high-energy event. In dogs, the ligament is already weakened before it ruptures.

The moment of obvious lameness is the endpoint of a months-long degenerative process.

ACVS: ligament rupture is "the result of subtle, slow degeneration that has been taking place over a period of time rather than the result of sudden trauma to an otherwise healthy ligament."

Fitzpatrick Referrals: "In the vast majority of dogs, the CrCL ruptures as a result of long-term degeneration, whereby the fibres weaken and fray over time, losing their structure and function."

The main causes and risk factors

Degeneration (aging and immune-mediated)

The underlying degenerative process in CCL disease involves progressive breakdown of collagen fibers within the ligament.

PMC (Cranial Cruciate Ligament Rupture Review): "The structural weakening of this joint due to the progressive degeneration of the ligament is the most accredited etiopathogenetic hypothesis."

The degeneration appears to involve both mechanical fatigue and immune-mediated inflammatory processes within the joint.

Synovitis (joint inflammation) often precedes complete rupture and may be detected during veterinary examination before full failure occurs.

Breed and genetics

ACVS: "Certain dog breeds are known to have a higher incidence: Rottweiler, Newfoundland, Staffordshire Terrier, Mastiff, Akita, Saint Bernard, Chesapeake Bay Retriever, and Labrador Retriever."

ACVS: "A genetic mode of inheritance has been shown for Newfoundlands and Labrador Retrievers."

Fitzpatrick Referrals: "Genetic factors are likely very important, with certain breeds being predisposed including Labradors, Rottweilers, Boxers, West Highland White Terriers, and Newfoundlands."

Breeds with low CCL disease incidence include Greyhounds, Dachshunds, Basset Hounds, and Old English Sheepdogs.

Fitzpatrick: "Supporting evidence for a genetic cause was obtained by assessment of family lines and the knowledge that many animals rupture both knees relatively early in life."

Obesity

ACVS: "Poor physical body condition and excessive body weight are risk factors for the development of CrCLD. Both of these factors can be influenced by pet owners."

PMC: "A predisposing factor is obesity, in which the concentrations of circulating inflammatory mediators increase, such as the concentrations of pro-inflammatory adipokines released from adipose tissue, which may contribute to degenerative phenomena."

Obesity matters in two ways: it increases the mechanical load on the CCL with every step, and it elevates systemic inflammation, which accelerates ligament degeneration.

A dog 10% overweight places significantly more stress on both stifle joints with every stride.

Tibial plateau angle (conformation)

The tibial plateau is the top surface of the tibia. In dogs, it slopes caudally. During weight-bearing, this slope creates a cranial shear force on the tibia that the CCL normally resists.

Fitzpatrick: "Increased tibial plateau angle (backwards slope at the top of the tibia) may play a role" in CCL disease.

Dogs with steeper tibial plateau angles experience greater cranial thrust with each step, increasing CCL load.

This is why TPLO and CBLO surgery (which reduce the tibial plateau angle) neutralize the instability rather than replacing the torn ligament.

Neuter status

Multiple studies have found that spayed and neutered dogs have higher rates of CCL disease than intact dogs. The relationship is stronger in some breeds than others.

Proposed mechanisms include the loss of sex hormones that influence joint development and ligament maturation, longer bone growth periods in dogs neutered before skeletal maturity, and altered body composition.

Contralateral (opposite knee) risk

NCBi (Radiographic Risk Factors study): "Among dogs presented with unilateral CCL rupture, a large proportion will develop contralateral CCL rupture within 12 to 24 months of initial diagnosis.

This risk is in the range of 22 to 54% at 6 to 17 months of diagnosis."

CSU: "At least half of the dogs that have a cruciate ligament problem in one knee will likely, at some future time, develop a similar problem in the other knee."

This bilateral risk reflects the systemic nature of CCL degeneration both ligaments are affected by the same genetic, hormonal, and conformation factors.

Partial tears: the warning stage

The CCL typically does not rupture all at once. Partial tears are common and produce intermittent hind limb lameness that owners sometimes attribute to a sprain.

CSU: "Partial tearing of the CCL is common in dogs and frequently precedes complete rupture."

ACVS: "Partial tearing of the CCL is common in dogs and almost always progresses to a full tear over time."

A dog with a partial CCL tear that receives cage rest and returns to activity will almost always eventually progress to complete rupture.

Surgical intervention at the partial tear stage can be considered for active dogs, though evidence on whether it prevents eventual complete rupture is limited.

Signs of CCL disease

• Hind limb lameness, especially after exercise
• Sudden onset of non-weight-bearing on a back leg
• Stiffness when getting up, especially after rest
• Muscle atrophy on the affected hind limb
• Thickening on the inside of the knee joint (medial buttress)
• Positive cranial drawer test or tibial compression test on orthopedic examination

Can CCL tears be prevented?

Risk cannot be eliminated in predisposed breeds, but it can be reduced.

ACVS: "Consistent physical conditioning with regular activity and close monitoring of food intake to maintain a lean body mass is advisable."

Evidence-based prevention strategies:

• Maintain healthy body weight (most impactful modifiable factor)
• Consistent, regular exercise rather than intermittent intense activity
• Avoid sudden load increases (the "weekend warrior" pattern)
• Discuss neutering timing with your vet, particularly in high-risk breeds

For the surgical treatment of CCL rupture, see CBLO surgery in dogs: cost, recovery, and success rate. For the surgery vs. conservative management decision, see canine cruciate injuries: surgery vs. conservative management.

For meniscal injury that often accompanies CCL tears, see torn meniscus surgery cost in dogs. For when CCL disease requires specialist referral, see when to refer for orthopedic surgery.

Frequently asked questions

My dog tore its CCL running in the yard. Wasn't that traumatic?

The event may have looked sudden, but the ligament was almost certainly already degenerated.

ACVS: the rupture is "the result of subtle, slow degeneration... rather than sudden trauma to an otherwise healthy ligament." The yard run was the last straw, not the cause.

Which dog breeds are at highest risk for CCL tears?

ACVS identifies Rottweilers, Newfoundlands, Staffordshire Terriers, Mastiffs, Akitas, Saint Bernards, Chesapeake Bay Retrievers, and Labrador Retrievers as high-incidence breeds. Fitzpatrick Referrals adds Boxers and West Highland White Terriers.

Does obesity really make that much difference?

Yes. Obesity increases both mechanical load on the CCL and systemic inflammation via adipokines from fat tissue.

It is the most modifiable risk factor maintaining healthy body weight is the single most impactful thing an owner can do for CCL disease prevention.

My dog had surgery on one knee. How long before the other goes?

NCBi data: the risk of contralateral CCL rupture is 22 to 54% within 6 to 17 months of the first diagnosis. Monitoring the other knee closely after the first diagnosis is important.

Maintaining lean body weight and avoiding abrupt increases in activity are the main protective strategies.

Can a dog with a partial CCL tear be managed without surgery?

Conservative management (rest, weight loss, physical therapy) may be attempted for partial tears, particularly in small dogs. But ACVS states partial tears "almost always progress to a full tear over time."

Discuss with an orthopedic specialist whether surgery at the partial tear stage is appropriate for your dog.

What is the difference between CCL and ACL?

CCL (cranial cruciate ligament) is the correct term in dogs; ACL (anterior cruciate ligament) is the human equivalent. They are anatomically similar structures that stabilize the knee joint.

The key clinical difference: in humans, ACL tears are usually traumatic; in dogs, CCL tears are almost always degenerative.

Resources

• ACVS. Cranial Cruciate Ligament Disease. acvs.org
• CSU Veterinary Health System. Canine Cruciate Ligament Injury. vetmedbiosci.colostate.edu
• Fitzpatrick Referrals. Cruciate Ligament Disease or Injury. fitzpatrickreferrals.co.uk
• NCBi PMC. Radiographic Risk Factors for Contralateral Rupture in Dogs with Unilateral CCL Rupture. ncbi.nlm.nih.gov
• PMC. Cranial Cruciate Ligament Rupture in Dogs: Review on Biomechanics, Etiopathogenetic Factors and Rehabilitation. ncbi.nlm.nih.gov

The Modified Maquet Procedure (MMP) is an evolution of the Tibial Tuberosity Advancement (TTA) that uses a titanium foam wedge instead of a cage to advance the tibial tuberosity.

It has been positioned as a less invasive, faster-to-perform alternative to TPLO for dogs with CCL rupture.

Published clinical evidence shows both procedures produce good outcomes, with TPLO demonstrating a slight advantage in objective gait analysis at 3 months.

Quick answer: A prospective randomized study found TPLO achieves 93.9% of normal peak vertical force vs 89.4% for MMP at 6 months — no significant difference in complications or OA progression. MMP is less invasive, faster, and generally less expensive. Both are appropriate for medium-to-large breed dogs.

Key takeaways

• TPLO achieves 93.9% of normal ground reaction force at 6 months vs 89.4% for MMP — numerically superior but not statistically significant
• No significant difference in major complications or OA progression was found between TPLO and MMP in the comparative study
• MMP is less invasive and faster to perform: a titanium foam wedge and partial osteotomy instead of TPLO's full proximal tibial cut
• MMP is generally less expensive than TPLO: shorter surgical time and different implant costs reduce the procedure price
• Early partial weight-bearing may occur sooner after MMP due to less invasive fixation and the partial osteotomy
• TPLO has a much larger evidence base: 25+ years of data vs limited MMP evidence

How each procedure works

TPLO (Tibial Plateau Leveling Osteotomy)

TPLO addresses CCL rupture by making a curved osteotomy through the proximal tibia and rotating the tibial plateau to approximately 5 degrees.

This changes joint biomechanics so the stifle is stable during weight-bearing without a functioning CCL. The osteotomy is held in place with a bone plate and screws.

Modified Maquet Procedure (MMP)

MMP is an adaptation of TTA in which the tibial tuberosity is advanced cranially by making a partial osteotomy in the tibial crest.

A porous titanium foam wedge is inserted into the gap and a fixation staple holds the construct in position.

The cranial advancement of the tuberosity repositions the patellar tendon to neutralize the cranial thrust that occurs in the CCL-deficient stifle the same biomechanical principle as TTA, with different implants.

Animal Works Veterinary Surgery describes MMP as using improved implants and surgical techniques designed to reduce operating time and minimize complications compared to standard TTA.

The titanium foam wedge promotes bone ingrowth and healing without the need for a cage or plate system. Bone healing in the MMP osteotomy site is typically complete at 90 days radiographically.

Clinical evidence: TPLO vs MMP

Primary comparative study

PubMed (prospective randomized controlled study, 61 dogs, 76 joints): dogs were treated with TPLO (n=30, 41 joints) or MMP (n=31, 35 joints) and compared with healthy controls.

Outcomes were assessed by clinical examination, radiography, and treadmill force plate gait analysis at 6 weeks, 3 months, and 6 months.

Results at 6 months:

• TPLO: 93.9% of normal peak vertical force (PVF), 85.9% of normal vertical impulse (VI)
• MMP: 89.4% of normal PVF, 79.9% of normal VI

At 3 months, significantly more TPLO patients were within the reference range for healthy dogs on peak vertical force. By 6 months, the difference was not statistically significant.

No significant difference was found in major complications or OA progression at any time point.

Conclusion from the study: "Although no significant differences were found between the surgical methods, TPLO patients showed superiority with regard to clinical outcome."

MMP standalone study

PMC (35 dogs, unilateral CCL rupture, MMP): significant improvement in ground reaction forces at all time intervals. At 90 days, 54.2% of patients had a Symmetry Index suggesting normal gait.

Complete bone healing on radiographs at 90 days. Major complication rate: 8.5% (3 of 35), minor complication rate: 2.8%.

Practical comparison

Which dogs are best suited to each?

MMP is often chosen for:

• Medium and large breed dogs where a less invasive approach is preferred
• Cases where surgical time is a clinical consideration
• Practices experienced in MMP technique
• Dogs where cost is a factor

TPLO is typically recommended for:

• Large and giant breed dogs with high joint loads
• Dogs with steep tibial plateau angles where TPLO provides more precise biomechanical correction
• Cases where the largest available evidence base is preferred
• Surgeons with established TPLO experience

Animal Hospital of Adel notes that both surgeries are effective, with MMP being less invasive, less expensive, and quicker to perform.

Walkerville Vet's evidence review concludes that TPLO gives slightly better objective results and that MMP is expected to outperform standard TTA, though more evidence is needed.

For the full TPLO pros and cons, see TPLO surgery pros and cons for dogs. For the full alternatives overview, see alternatives to TPLO surgery for dogs.

Frequently asked questions

Is MMP as effective as TPLO for large dogs?

The evidence suggests TPLO has a slight advantage at 3 months, with equivalent outcomes by 6 months in the primary comparative study.

Most surgeons still prefer TPLO for large and giant breeds due to the larger evidence base and slightly superior short-term objective results. MMP is appropriate for many large dogs in experienced hands.

How much cheaper is MMP than TPLO?

MMP is generally less expensive than TPLO due to shorter surgical time and different implant costs. The specific difference varies by practice, region, and surgeon.

Ask your veterinarian for a direct cost comparison for your dog's specific case.

What is the complication rate for MMP compared to TPLO?

The MMP standalone study reported an 8.5% major complication rate. TPLO complication rates across the literature range from 14 to 34%.

However, these figures come from different study populations and settings, making direct comparison difficult. Neither procedure is free of risk.

How long does MMP recovery take compared to TPLO?

Both procedures require 8 to 12 weeks of restricted activity, though MMP's less invasive partial osteotomy may allow earlier partial weight-bearing in some dogs.

Full activity return for both procedures is typically at 4 to 6 months.

Can a dog have TPLO if MMP fails?

Yes. TPLO can be performed as a revision if MMP results in ongoing instability or poor function. The converse is less common.

Discuss revision options with an orthopedic specialist if your dog is not progressing as expected after MMP.

Resources

• PubMed. Outcome after Tibial Plateau Levelling Osteotomy and Modified Maquet Procedure in Dogs with CCL Rupture. pubmed.ncbi.nlm.nih.gov
• PMC. Outcome after Modified Maquet Procedure in Dogs: Force Plate Gait Analysis. ncbi.nlm.nih.gov
• Animal Works Veterinary Surgery. MMP vs TPLO. animalworksvets.com
• Dog Knee Injury. Modified Maquet Procedure (MMP Surgery) for Dogs. dogkneeinjury.com
• Walkerville Vet. Which ACL Surgery Is Best for Dogs? walkervillevet.com.au

TPLO has a high overall success rate, but complications do occur. The published overall complication rate ranges from 10 to 34%, with most complications being minor and manageable.

Knowing what to watch for -- and when a sign requires a same-day call vs. a mention at the next scheduled appointment -- allows owners to respond appropriately.

Quick answer: The 15 most common post-TPLO complications: surgical site infection, seroma, implant loosening or failure, osteomyelitis, late meniscal tear, tibial tuberosity fracture, delayed bone healing, persistent lameness, non-union, intra-articular screw placement, nerve damage, patellar tendon thickening, patellar luxation, progressive osteoarthritis, and contralateral CCL rupture. Most are minor and manageable.

Key takeaways

• The overall complication rate is 10 to 34%: most complications are minor (swelling, mild infection); serious complications such as implant failure or osteomyelitis are less common
• SSI is the most frequent single complication: reported in 2.9% to 17.3% of TPLO procedures; most are superficial and treatable with antibiotics if caught early
• Late meniscal tear occurs in 1.8% to 10.5% of cases where the meniscus was normal at surgery; it presents as sudden lameness return with meniscal click
• Tibial tuberosity fracture is reported in 1 to 9% of TPLO cases: incorrect positioning and oversized saw blades are the main risk factors
• Implant-associated infection occurred in 3.4% and osteomyelitis in 0.6% across numerous studies; osteomyelitis requires strong antibiotics for 4 to 6 months and sometimes plate removal
• Contralateral CCL rupture is a significant long-term risk: 30 to 40% of dogs develop rupture of the opposite CCL; owners should monitor the opposite stifle

Early complications (weeks 0 to 8)

1. Surgical site infection (SSI)

The most common complication. SSI ranges from superficial incisional infection (treatable with oral antibiotics and wound care) to deep implant-associated infection requiring plate removal.

Signs: redness spreading beyond the incision, warmth, swelling, cloudy or malodorous discharge.

Incidence: 2.9% to 17.3% per published literature; the PMC 769-TPLO study (769 procedures) found 8.5%.

Management: culture-directed antibiotics for superficial infections; surgical debridement and sometimes plate removal for deep implant infections.

2. Seroma

A localized collection of clear serous fluid under the skin near the incision, typically appearing 1 to 3 weeks post-surgery.

Signs: soft, fluctuant swelling at or near the incision; no warmth or redness; clear fluid if aspirated.

Incidence: common; most resolve without treatment.

Management: monitoring; aspiration if large or causing discomfort; bandaging in some cases.

3. Acute lameness from overactivity

The dog is over-active during the restriction period and bears too much load on the plate before the osteotomy heals.

Signs: sudden worsening of lameness after a period of improvement; may indicate implant stress or early failure.

Management: strict crate rest; radiographic assessment to rule out implant displacement.

4. Wound dehiscence

The incision edges separate before fully healing. More common in dogs that lick the incision despite an e-collar that fits incorrectly.

Signs: open wound edges, sometimes with tissue visible.

Management: cleaning and re-closure in most cases; e-collar compliance review.

Mid-term complications (weeks 4 to 16)

5. Delayed bone healing

The osteotomy is not showing expected consolidation on radiographs at the 6 to 8 week checkpoint.

Signs: radiographic evidence of widening osteotomy gap or absence of callus formation; may or may not produce clinical signs.

Risk factors: infection, excessive activity, poor bone quality (older dogs, large breeds), NSAIDs at high doses for extended periods.

Management: extended activity restriction; investigate for underlying infection; nutritional support.

6. Tibial tuberosity fracture

A fracture of the tibial tuberosity (the prominence where the patellar tendon attaches) caused by the osteotomy saw blade coming too close to this structure.

Incidence: 1 to 9% per Laguna Woods Vets; higher in dogs with high TPA, high body weight, and large TPA change.

Signs: acute severe lameness; radiographic evidence of fracture.

Management: surgical repair or conservative management depending on displacement.

7. Late meniscal tear

A meniscal tear occurring after TPLO in a meniscus that appeared normal at surgery. See the dedicated meniscal tear article for full detail.

Incidence: 1.8% to 10.5% of cases with normal meniscus at TPLO (Dog Discoveries).

Signs: sudden lameness regression; meniscal click on movement; pain on stifle manipulation.

Management: partial meniscectomy.

8. Implant loosening or failure

The plate or screws shift, bend, or break -- typically from premature overactivity before the osteotomy heals.

Signs: sudden severe lameness; pain at plate site; radiographic evidence of screw loosening, plate migration, or osteotomy displacement.

Management: revision surgery in most cases of significant displacement.

Long-term complications (months 3 and beyond)

9. Osteomyelitis

Bone infection extending from a superficial SSI or introduced via hematogenous seeding. Difficult to treat.

Incidence: 0.6% per Dog Discoveries citing multiple studies.

Signs: persistent lameness; draining tract; radiographic bone destruction, periosteal reaction, or sequestrum.

Management: Laguna Woods Vets confirms osteomyelitis requires strong antibiotics for 4 to 6 months; a wound culture aids antibiotic selection; plate removal is often required.

10. Non-union

The osteotomy fails to heal, resulting in permanent instability at the cut site.

Risk factors: infection, inadequate fixation, excessive motion, poor blood supply.

Signs: persistent lameness; radiographic evidence of osteotomy gap persisting beyond 16 weeks with no bridging callus.

Management: revision surgery, bone grafting, and often implant revision.

11. Intra-articular screw placement

A screw tip violates the joint space, causing joint damage and persistent pain. Best identified on the postoperative radiograph.

Signs: ongoing lameness; pain on stifle range of motion; radiographic evidence of screw in joint space.

Management: removal of the offending screw.

12. Persistent lameness without identifiable cause

Some dogs have persistent mild lameness despite uncomplicated bone healing and no identifiable complication. This may reflect residual arthritis progression, muscle atrophy, or subclinical meniscal issues.

Management: rehabilitation, joint supplements, and management of secondary osteoarthritis.

13. Patellar tendon thickening

Fibrous thickening of the patellar tendon develops in some TPLO dogs over time. This is typically not clinically significant.

Signs: palpable thickening of the patellar tendon on examination; usually incidental finding.

Management: generally none required; physiotherapy in some cases.

14. Patellar luxation

Medial patellar luxation can develop or worsen after TPLO, particularly if the plate is contoured in a way that affects patellar tracking.

Signs: intermittent lameness, popping of the patella medially on examination.

Management: surgical correction (trochleoplasty and tibial crest transposition) in symptomatic cases.

15. Progressive osteoarthritis

All dogs with CCL disease develop some arthritis progression regardless of surgical technique. TPLO slows but does not stop this process.

Signs: gradual stiffness, lameness that is worse after rest, reduced activity tolerance.

Management: joint supplements (omega-3 fatty acids, glucosamine), weight management, NSAIDs for flares, hydrotherapy.

Contralateral CCL rupture: a special consideration

Contralateral CCL rupture is not a complication of TPLO but deserves mention.

Midvalley Animal Clinic confirms it is very common (30 to 40% of patients) for both knees to develop this ligament injury.

Owners of dogs that have had unilateral TPLO should monitor the opposite stifle for early signs.

For the infection guide, see TPLO plate infection signs and treatment. For the meniscal tear guide, see dog meniscus tear after TPLO surgery.

For the failure rate overview, see TPLO failure rate in dogs. For the implant failure signs, see TPLO implant failure signs and causes.

Frequently asked questions

What is the most common serious complication after TPLO?

Deep implant-associated infection requiring plate removal is the most common serious complication, with an implant removal rate of 3.5 to 7.5% of procedures (ResearchGate).

Osteomyelitis (0.6%) and tibial tuberosity fracture (1 to 9%) are other serious but less common complications.

Is a 10 to 34% complication rate high for an orthopedic surgery?

The range is real but the majority of complications are minor -- a seroma, mild superficial infection treated with antibiotics, or a brief period of increased lameness.

Serious complications requiring revision surgery are significantly less common. TPLO's overall success rate (93% limb function restoration at 1 year per a 2013 study) reflects that most dogs recover well.

Can complications be prevented?

Most can be reduced in risk but not eliminated.

Owner-controlled risk reduction: e-collar compliance, strict activity restriction for 8 to 12 weeks, daily incision inspection, and attending all scheduled vet appointments.

What happens if my dog develops two complications simultaneously?

This is uncommon but does occur (for example, SSI leading to delayed bone healing). Management is coordinated by your surgical team based on the severity and interaction of the complications.

Contact your vet immediately for any concern.

Should I be worried every time my dog limps?

A degree of lameness is expected throughout the recovery period. The key signal is trajectory: steadily improving lameness is expected; suddenly worsening or reversed lameness is not.

Monitor for any sudden changes and contact your vet for trajectory reversals.

Resources

• PMC. Surgical Site Infection After 769 TPLOs. pmc.ncbi.nlm.nih.gov
• Laguna Woods Vets. TPLO Surgery Complications. lhah.com
• Dog Discoveries. TPLO Failure and Complications in Dogs. dogdiscoveries.com
• Clinician's Brief. Common Tibial Plateau-Leveling Osteotomy Complications. cliniciansbrief.com

Some degree of fluid accumulation after TPLO surgery is normal and expected.

The surgery involves cutting and rotating the tibia a significant tissue injury that triggers an inflammatory response, part of which is fluid production.

The question is not whether fluid will appear, but whether the fluid you are seeing is a normal healing response or a sign of something that needs attention.

Quick answer: Fluid buildup after TPLO is usually a seroma — clear serum under the skin that is not an infection. Small seromas resolve in 1 to 3 weeks with rest. Call your vet if swelling is hot, rapidly growing, producing discharge, or accompanied by fever.

Key takeaways

• Seroma is the most common fluid buildup after TPLO: clear serum under the skin, not an infection, resolving with rest in 1 to 3 weeks
• Small seromas are managed with rest: the body reabsorbs the fluid naturally; no intervention is needed for most small seromas
• Large or persistent seromas may require needle aspiration: this must be done under sterile veterinary conditions; never drain at home
• Ankle swelling at 3 to 5 days post-surgery is normal: gravity pulls post-surgical fluid downward to the ankle; TPLO Info confirms this is routine
• Warning signs requiring vet contact: rapidly increasing swelling, warmth, redness, pus, foul odor, fever, or lethargy
• Activity restriction is the most important prevention: excessive movement is the leading cause of seroma formation after TPLO

What is fluid buildup after TPLO surgery?

Fluid buildup after TPLO surgery typically takes one of two forms: seroma or post-surgical edema.

A seroma is a collection of serum the clear, protein-rich fluid component of blood that leaks from disrupted blood vessels and lymphatic channels during surgery.

It pools in the dead space beneath the skin at the surgical site. Seromas feel soft, fluctuant (squishy), and are usually not warm or painful when small. They are not infections.

Post-surgical edema is broader tissue swelling caused by the inflammatory response to surgery.

This is expected in the first few days after any major orthopedic procedure and typically peaks at 48 to 72 hours before gradually resolving.

Both are distinct from hematoma (a collection of blood) and from infectious fluid (which appears purulent, has an odor, and accompanies systemic illness signs).

Why fluid builds up after TPLO

TPLO surgery creates significant soft tissue disruption.

The curved osteotomy cut, muscle retraction, and plate placement create dead space under the skin.

Fluid accumulates in this space before the tissues close together during healing.

Key contributing factors:

Excessive activity after surgery: the most preventable cause. Every time the operated leg moves beyond gentle weight-bearing, tissue planes are disrupted and more serum leaks into the dead space. TPLO Info confirms that the most common post-surgical cause of seroma is excessive movement of the knee.

Surgical technique: a longer or more complex procedure increases tissue disruption and the resulting dead space. Most surgeons use subcutaneous sutures and tissue closure techniques to minimize this, but some seroma formation remains common even with optimal technique.

Dog size and body composition: larger dogs and those with more subcutaneous fat tend to have more dead space at the osteotomy site and are more prone to seroma formation.

Licking or chewing at the incision: disrupts the healing wound edges and can introduce bacteria into a seroma, converting a benign fluid collection into an infected abscess. The E-collar must remain on at all times.

Normal vs. abnormal fluid buildup: how to tell the difference

Treatment options

Observation and strict rest: for small seromas (under 2 to 3 cm), the standard approach is to enforce activity restriction and allow the body to reabsorb the fluid. Small seromas typically resolve within 1 to 3 weeks. Cold compresses in the first few days reduce new inflammation.

Needle aspiration: large or uncomfortable seromas may be drained by your veterinarian using a sterile needle and syringe. This is a simple outpatient procedure but must be performed aseptically to avoid introducing infection. Never drain a seroma at home.

Compression bandaging: gentle compressive bandaging reduces the dead space available for fluid accumulation and can help prevent reformation after aspiration. This is typically applied by the veterinarian.

Surgical drain placement: if fluid continues to accumulate despite aspiration, a closed suction drain can be placed temporarily. This is rarely needed but is an option for persistent, large seromas.

Antibiotics: only if bacterial infection is confirmed or strongly suspected. Most seromas do not require antibiotics. Prescribing antibiotics for a non-infected seroma is not appropriate and contributes to antimicrobial resistance.

When to contact your veterinarian

Contact your vet promptly if you notice any of the following:

• Swelling that is rapidly increasing in size, especially in the first week
• The swollen area becomes warm, red, or painful to touch
• Any discharge, pus, or unusual odor from the incision or the swollen area
• Your dog develops fever, lethargy, loss of appetite, or stops bearing weight
• The seroma persists beyond 3 to 4 weeks without improvement

For the related article on incision site complications, see seroma in dogs after TPLO surgery. For the full complications overview, see 15 common complications after TPLO surgery in dogs.

For incision infection specifics, see TPLO incision infection symptoms and prevention.

Frequently asked questions

Is it normal to have a lump under the TPLO incision?

Yes, in most cases. A soft, non-painful lump that develops within the first 1 to 2 weeks under the TPLO incision is typically a seroma.

As long as it is not hot, rapidly growing, or producing discharge, it is usually a benign post-operative finding. Monitor it daily and report any changes to your vet.

How long does post-TPLO swelling last?

Most post-surgical edema resolves within 3 to 7 days as the acute inflammatory phase subsides.

Seromas take longer typically 1 to 3 weeks for small ones, and potentially 4 to 6 weeks for larger ones if they reform after aspiration.

Can I massage the fluid away?

Gentle massage around (not directly over) the incision can encourage local circulation, but vigorous massage of a seroma risks rupturing it and introducing bacteria.

TPLO Info notes that ankle swelling that develops 3 to 5 days post-surgery can be massaged and iced. For the surgical site itself, follow your vet's specific guidance.

What happens if a seroma is left untreated?

Most small seromas reabsorb on their own without problems.

A larger seroma that is not treated may persist for weeks or months, become uncomfortable due to pressure, or rarely become infected if bacteria enter through the overlying skin.

Monitoring and reporting changes to your vet is the key strategy.

Can my dog's activity level cause more fluid to build up?

Yes. Excessive activity is the most preventable cause of seroma formation and recurrence after aspiration. Every unnecessary movement of the operated leg disrupts healing tissue planes and drives more fluid production.

Strict confinement and leash-only activity are essential.

Resources

• TPLO Info. Recovery FAQs. tploinfo.com
• Vetplayas. Understanding Swelling After TPLO Surgery. vetplayas.com
• VCA Animal Hospitals. Seroma in Dogs. vcahospitals.com
• ACVS. Cranial Cruciate Ligament Disease. acvs.org