TPLO surgery is not a cure for arthritis it is a mechanical correction that stabilizes the stifle and slows the rate at which arthritis progresses.

Understanding what happens to the joint long-term is one of the most important conversations an owner can have with their veterinarian.

Quick answer: All dogs develop some OA after CCL rupture, and it continues after TPLO. Research shows OA progresses more slowly after TPLO than after TTA or non-surgical management. Long-term management includes weight control, joint supplements, NSAIDs, and controlled exercise.

Key takeaways

• OA develops in all dogs with CCL rupture: TPLO stops instability that accelerates OA but does not eliminate existing arthritis
• TPLO slows OA progression: a PubMed study found OA progressed significantly more after TTA than TPLO (p=0.003)
• Radiographic OA scores increase significantly at 24 months post-TPLO in dogs with complete CCL rupture
• MedVet confirms: all dogs develop arthritis within weeks of ligament tearing, but knee stabilization slows the progression
• Weight management is the most impactful owner intervention: excess weight increases stifle load and accelerates cartilage wear
• Long-term NSAID use requires veterinary guidance: kidney and liver monitoring is required for dogs on chronic NSAID therapy

Why arthritis develops after TPLO

CCL rupture damages the joint before surgery even begins. The instability the tibia sliding forward under the femur with each step causes:

• Cartilage microtrauma from abnormal loading
• Synovial membrane inflammation, releasing enzymes that break down cartilage
• Medial meniscus injury (30 to 40% of CCL dogs have concurrent meniscal damage)
• Subchondral bone remodeling in response to abnormal forces

TPLO corrects the mechanical instability, but the cartilage damage already present does not reverse.

The joint has a permanently altered surface that is more susceptible to progressive OA than an intact, never-injured stifle.

Surgical trauma from the TPLO procedure itself also contributes.

The operation creates local inflammation that can accelerate cartilage breakdown in the first months, even as it creates the long-term stability that slows OA over years.

What research shows about OA progression after TPLO

Rate of progression

A prospective radiographic study (Rayward et al., 40 dogs, JSAP) found a significant increase in mean osteophyte score between the preoperative assessment and 6-month post-surgical examination.

However, in the majority of dogs in this study, there was no further radiographic progression of osteophytosis during the study period.

A larger long-term study (94 TPLO dogs, 133 stifles, followed to 3+ years) found OA progressed more after TTA (p=0.003) and in dogs with bilateral stifle surgery (p=0.022).

Dogs treated with TPLO had less pain and fewer mobility issues than TTA dogs at long-term follow-up, including better scores for stiffness, limping, jumping, climbing, and quality of life.

Functional outcomes vs. radiographic findings

Radiographic OA does not always correlate directly with clinical signs. Many dogs have significant osteophyte formation on radiographs but remain comfortable and functional with appropriate management.

Conversely, some dogs with relatively mild radiographic changes show significant clinical signs.

Early signs of arthritis after TPLO

Signs typically appear gradually rather than acutely. Watch for:

Morning stiffness: reluctance to get up or moving stiffly for the first few minutes after resting, improving with gentle activity.

Reduced activity: decreased willingness to run, jump, climb stairs, or sustain exercise at previous levels.

Lameness after exercise: the dog is comfortable on a short leash walk but noticeably lame after a longer walk or play session.

Behavioral changes: irritability, reluctance to be touched on the operated limb, reduced interaction with family members.

Muscle loss: loss of thigh muscle mass on the operated limb as the dog offloads it.

Joint swelling: persistent low-grade swelling around the stifle due to chronic synovial inflammation.

Long-term management of post-TPLO arthritis

Weight management

The most impactful single intervention. Every pound of excess body weight multiplies the compressive force on the stifle joint with each step.

Dogs at ideal body condition score 4 to 5 out of 9 consistently have better long-term joint outcomes than overweight dogs.

Controlled, low-impact exercise

Regular, low-impact exercise maintains muscle mass, supports joint fluid circulation, and prevents joint stiffness. Leash walks on flat terrain, swimming, and underwater treadmill work are ideal.

High-impact activities ball chasing, jumping, sustained running accelerate cartilage wear.

Joint supplements

Glucosamine and chondroitin sulfate support cartilage health and reduce inflammation. Omega-3 fatty acids (EPA and DHA) have anti-inflammatory properties with evidence for benefit in canine OA.

These are maintenance-level interventions appropriate for all post-TPLO dogs as lifelong support.

NSAIDs

Non-steroidal anti-inflammatory drugs (meloxicam, carprofen, grapiprant) are the most effective pharmaceutical interventions for OA pain.

They are used on a needs basis for dogs with intermittent discomfort, or continuously for dogs with chronic significant OA pain.

Kidney and liver function monitoring is required for dogs on long-term NSAID therapy.

Disease-modifying osteoarthritis agents

Librela (bedinvetmab), an anti-nerve growth factor monoclonal antibody approved for canine OA pain, is a newer option for dogs that do not respond adequately to NSAIDs or cannot tolerate them.

Discuss with your veterinarian if your dog's arthritis is not well-controlled with standard approaches.

Physical rehabilitation

Certified canine rehabilitation practitioners can provide individualized programs combining therapeutic exercises, hydrotherapy, laser therapy, and acupuncture to maintain muscle mass, joint mobility, and overall comfort.

For the full recovery guide that sets the foundation for arthritis prevention, see 10 essential TPLO recovery tips for pet owners. For the long-term outcomes data, see long-term outcomes of TPLO surgery.

For the complications overview including OA, see 15 long-term effects of TPLO surgery on dogs. For the lameness guide covering OA-related limping, see lameness after TPLO surgery in dogs.

Frequently asked questions

Does every dog get arthritis after TPLO?

Yes. All dogs that rupture a CCL develop some degree of OA in that stifle the process begins at the time of ligament injury and is not fully stopped by surgery.

TPLO significantly slows the rate of progression compared to no treatment or less effective surgeries, but it does not prevent OA entirely.

How quickly does arthritis progress after TPLO?

Research shows a significant increase in radiographic OA scores at 6 months post-TPLO, then a more gradual increase over the following 24 to 36 months.

In many dogs, radiographic progression stabilizes after 2 to 3 years. Clinical signs depend on individual pain tolerance and concurrent management.

Can I see signs of arthritis before X-rays show it?

Yes. Dogs show clinical signs (stiffness, reduced activity, gait changes) often before radiographic changes are apparent.

This is why monitoring behavior and function not just waiting for X-ray evidence is important for timely intervention.

Is arthritis the same as TPLO failure?

No. Arthritis progression is expected and does not constitute surgical failure. TPLO failure refers to mechanical problems implant complications, non-union, persistent instability.

OA progression is a separate, expected degenerative process that is managed over the dog's lifetime.

What is the single best thing I can do to slow arthritis after TPLO?

Maintain your dog at an ideal lean body weight.

This single factor has the greatest impact on the rate of cartilage wear, joint inflammation, and long-term comfort of any intervention within owner control.

Resources

• PubMed. Extended Long-Term Radiographic and Functional Comparison of TPLO vs TTA. pubmed.ncbi.nlm.nih.gov
• PubMed. Progression of Osteoarthritis Following TPLO Surgery: A Prospective Radiographic Study of 40 Dogs. pubmed.ncbi.nlm.nih.gov
• MedVet. Dogs and Knee Surgery: Understanding TPLO Surgery. medvet.com
• ACVS. Cranial Cruciate Ligament Disease. acvs.org
• VCA Animal Hospitals. Tibial Plateau Leveling Osteotomy (TPLO) in Dogs. vcahospitals.com

Urinary incontinence after TPLO surgery is not a common complication, but it does occur and is understandably alarming for owners.

In most cases it is a temporary consequence of anesthesia, pain medication, stress, or reduced mobility not a sign of a serious surgical problem.

Knowing the causes, the timeline, and when to call your vet helps you respond appropriately.

Quick answer: Incontinence after TPLO is usually temporary from anesthesia, pain medications, reduced mobility, or stress. Most cases resolve within days to weeks. Call your vet if it persists beyond 2 to 4 weeks or comes with bloody urine or fever.

Key takeaways

• Immediate post-TPLO incontinence is most often from anesthesia or nerve irritation: both are temporary and resolve within days to weeks
• Opioid pain medications cause urinary retention or reduced bladder awareness in some dogs this resolves as medications are tapered
• Postoperative swelling may temporarily irritate nerves involved in bladder control; this resolves with swelling
• Reduced mobility is a practical contributor: a confined, painful dog may not signal in time or reach the door quickly
• Stress after major surgery can cause accidents in previously house-trained dogs; this is behavioral, not neurological
• Genuine nerve damage from TPLO is rare: incontinence persisting beyond 6 weeks warrants neurological evaluation

Why dogs may become incontinent after TPLO surgery

Anesthesia effects

General anesthesia temporarily suppresses normal nerve function throughout the body, including the neural pathways that control bladder filling awareness and sphincter tone.

As anesthetic drugs are metabolized over the 12 to 24 hours after surgery, some dogs have reduced bladder control.

This is the most common cause of immediate post-surgical incontinence. It resolves as anesthesia fully clears, typically within 24 to 48 hours.

Nausea, disorientation, and general sedation from anesthesia also mean the dog may not signal clearly when they need to go outside.

Scheduled outdoor bathroom trips every 2 to 4 hours in the first 24 to 48 hours post-surgery help manage this.

Opioid and sedative medications

Opioid pain medications commonly prescribed after TPLO affect bladder control in two ways: they reduce awareness of bladder fullness, and in some dogs cause urinary retention.

Both effects resolve as medications are tapered in the days following surgery.

Retention and incontinence are opposite problems retention is not urinating at all, while incontinence is involuntary urination but both can occur at different times as different medications have their effects.

As pain medications are tapered in the days after surgery, these effects resolve for most dogs.

Postoperative swelling and nerve irritation

The proximal tibia is surrounded by neurovascular structures. Postoperative swelling around the surgical site may temporarily compress or irritate nerves that travel to the bladder and urethra.

This is more likely in the first week after surgery when swelling is at its peak.

This type of incontinence improves as swelling resolves and typically does not indicate permanent nerve damage.

Reduced mobility

A dog recovering from TPLO is confined, in pain, and may not reach the door quickly enough when the bladder signals urgency.

This is a practical mobility problem, not a neurological one.

Frequent scheduled outdoor trips every 2 to 4 hours in the first week reduce accidents significantly. Waterproof mattress covers and washable bedding help manage the recovery period hygienically.

Stress and behavioral response

Major surgery is a significant stressor. Pain, an unfamiliar environment, an E-collar, restricted movement, and disrupted routine can cause previously house-trained dogs to have accidents unrelated to neurological dysfunction.

This type of incontinence typically resolves as the dog settles into a recovery routine at home, usually within 1 to 2 weeks.

Pre-existing urinary conditions

Dogs with pre-existing urinary sphincter mechanism incompetence (common in middle-aged spayed females), bladder infections, or weak bladder control may show worsened incontinence after surgery.

Anesthesia, medications, and reduced mobility all unmask or worsen underlying conditions.

If your dog was occasionally leaking urine before surgery, report this to your vet during the pre-surgical assessment so appropriate management can be planned for the recovery period.

Types of post-TPLO incontinence by timing

Immediate (within 24 to 48 hours): almost always anesthesia effects or opioid medication. Expected and self-limiting.

Early post-operative (days 3 to 14): medication effects, swelling-related nerve irritation, mobility limitation, or stress. Usually self-limiting with appropriate management.

Delayed onset (weeks 2 to 6): may indicate a developing urinary tract infection (UTI), which can occur after catheterization during surgery or from reduced immune response. A urinalysis is warranted if incontinence appears or worsens after initial improvement.

Chronic (beyond 6 weeks): uncommon. If incontinence persists beyond 6 weeks without improvement, veterinary evaluation for nerve damage or underlying urinary tract disease is appropriate.

Home management during recovery

• Scheduled outdoor bathroom trips every 2 to 4 hours for the first 1 to 2 weeks
• Waterproof mattress protectors and washable bedding in the recovery area
• Non-slip surfaces to reduce the effort required to stand and move toward the door
• Monitor urine color and odor cloudy, bloody, or foul-smelling urine suggests UTI
• Keep the genital area clean to prevent skin irritation from urine contact
• Use a belly band (for males) or absorbent dog diapers if incontinence is significant

When to contact your veterinarian

Call your vet if:

• The dog cannot urinate at all for more than 12 to 24 hours after surgery
• Urine is bloody, cloudy, or has a strong unusual odor (UTI signs)
• Incontinence is accompanied by straining, crying during urination, or frequent squatting without producing urine
• Incontinence worsens after initial improvement
• The dog has persistent incontinence beyond 2 to 4 weeks without any improvement
• Incontinence is combined with significant worsening lameness or systemic signs

For the not-peeing guide that covers urinary retention after TPLO, see dog not peeing after TPLO surgery: causes and care.

For the full TPLO complications reference, see 15 common complications after TPLO surgery in dogs.

For TPLO plate infection signs that may be contributing to systemic effects, see TPLO plate infection signs and treatment.

For post-op whining that may relate to the same pain driving accidents, see dog whining after TPLO surgery: causes and care.

Frequently asked questions

Is incontinence normal after TPLO surgery?

Temporary incontinence particularly in the first 24 to 48 hours is a recognized post-surgical finding related to anesthesia and opioid pain medications.

It is not an expected routine outcome, but it is not rare. If it resolves within a few days, it was almost certainly anesthesia-related.

Could my dog have nerve damage from TPLO surgery?

True nerve damage causing persistent incontinence from TPLO is rare. TPLO is performed at the proximal tibia, which is some distance from the pelvic nerves controlling bladder function.

Temporary nerve irritation from swelling is much more common than actual nerve injury and resolves as swelling subsides.

My dog was continent before TPLO and is now leaking at night. Why?

Nighttime leaking specifically is typical of urinary sphincter mechanism incompetence (USMI) a condition where the urethral sphincter relaxes during sleep or rest.

If this is new after surgery, anesthesia and opioid medications may have temporarily worsened underlying borderline sphincter function.

If it continues beyond 2 to 3 weeks, a vet visit for urinalysis and discussion of phenylpropanolamine (PPA) or other treatment is appropriate.

How do I know if my dog has a UTI after TPLO?

Signs of UTI include: cloudy or bloody urine, strong or unusual odor, frequent small amounts of urination, straining to urinate, and licking at the genital area more than normal.

Some dogs with UTI also show lethargy and decreased appetite. Urinalysis and culture confirm the diagnosis.

Should I limit my dog's water intake to reduce accidents?

No. Do not restrict water. Hydration is important for recovery and kidney function. Restricting water can concentrate the urine and increase UTI risk.

Instead, manage accidents through scheduled outdoor trips and waterproof bedding.

Resources

• VCA Animal Hospitals. Tibial Plateau Leveling Osteotomy (TPLO) in Dogs. vcahospitals.com
• ACVS. Cranial Cruciate Ligament Disease. acvs.org
• PetMD. Urinary Incontinence in Dogs. petmd.com
• Midwest Veterinary Specialists. Post-Operative Care Following TPLO. midwestveterinaryspecialists.com

TPLO surgery requires general anesthesia that is tailored to the individual patient. For most healthy adult dogs, TPLO anesthesia is straightforward and low-risk.

For older dogs, obese dogs, or those with concurrent medical conditions, the anesthetic plan requires additional planning.

Understanding what the protocol involves helps owners know what to expect and how to prepare their dog.

Quick answer: TPLO anesthesia includes a preoperative blood panel; premedication with an opioid and sedative; induction with propofol or alfaxalone; maintenance with isoflurane or sevoflurane; continuous monitoring; and multimodal pain management including NSAIDs, nerve blocks (sciatic/femoral or epidural), and post-operative opioids.

Key takeaways

• Preoperative blood work is standard for all TPLO patients: CBC and biochemistry identify organ dysfunction and conditions that increase anesthetic risk
• TPLO anesthesia is multimodal: combining opioids, NSAIDs, nerve blocks, and inhalant anesthetic reduces total drug doses and improves pain control
• Nerve blocks are now standard in TPLO anesthesia: femoral and sciatic blocks with bupivacaine reduce post-operative opioid requirements
• A published feasibility study achieved total opioid-free post-operative analgesia in TPLO dogs using nerve blocks, ketamine, isoflurane, and meloxicam
• Epidural analgesia reduces post-operative opioid requirements by 36% compared to no epidural, per PMC study data
• Food is withheld 8 to 12 hours before surgery to reduce aspiration risk; water restriction is typically shorter

Pre-anesthetic assessment

Every dog undergoing TPLO is evaluated before anesthesia to identify risk factors and optimize the anesthetic plan.

Physical examination: body weight, cardiovascular and respiratory status, mucous membrane color and capillary refill, hydration status, and assessment of concurrent conditions.

Blood work: complete blood count (CBC) detects anaemia, infection, and platelet abnormalities. Biochemistry panel assesses kidney function (creatinine, BUN), liver function (ALT, ALP, bilirubin), blood glucose, and electrolytes. These results determine anesthetic drug selection and guide fluid therapy.

ASA classification: anesthesiologists use the American Society of Anesthesiologists (ASA) physical status classification (1 to 5) to communicate overall health status. Most TPLO patients are ASA class 1 (healthy) or 2 (mild systemic disease). Dogs with significant cardiac, renal, or hepatic disease may be ASA 3 or higher and require additional monitoring or modified protocols.

Premedication

Premedication is given 20 to 40 minutes before induction.

It serves to calm the dog, reduce anxiety, provide early analgesia (preemptive analgesia), reduce the amount of induction and maintenance agent required, and make induction smoother.

Opioids (most common premedication component for TPLO):

• Hydromorphone: commonly used as a premedication; the PubMed perioperative analgesia study used hydromorphone plus acepromazine as premedication in all 56 TPLO dogs
• Methadone: provides both opioid analgesia and NMDA receptor antagonism; commonly used as a premedication in many European centres
• Morphine: used in some protocols, particularly when combined with epidural administration

Sedatives:

• Acepromazine: a phenothiazine tranquilizer that provides reliable sedation; use is reduced in patients with cardiovascular compromise due to vasodilatory effects
• Medetomidine or dexmedetomidine: alpha-2 agonists providing sedation, analgesia, and muscle relaxation; used in the opioid-free feasibility protocol (PMC 2024)
• Midazolam: benzodiazepine used particularly in geriatric or debilitated dogs for its minimal cardiovascular effects

Anesthetic induction

Induction agents produce rapid unconsciousness, allowing placement of an endotracheal tube for airway control.

Propofol: the most commonly used induction agent in healthy dogs. Provides smooth, rapid induction with a short duration, making induction-to-intubation management easy.

Alfaxalone: a neuroactive steroid with a similar profile to propofol. Used in some protocols as an alternative, particularly in smaller dogs or where propofol is not available.

Ketamine + midazolam: used in some protocols as an alternative induction combination, particularly when some degree of analgesia is desired at induction. Also used in opioid-sparing protocols.

Intraoperative maintenance

Inhalant anesthetics (isoflurane or sevoflurane) are delivered via endotracheal tube to maintain unconsciousness throughout the surgery.

Isoflurane is the most widely used agent in veterinary anaesthesia for TPLO. Sevoflurane provides faster recovery but is more expensive. Both are effective.

IV constant rate infusions (CRI) during surgery augment inhalant anesthesia and reduce inhalant requirements:

• Ketamine CRI: used in opioid-sparing protocols; the PMC feasibility study used ketamine CRI at 0.6 mg/kg/h throughout surgery
• Morphine-lidocaine-ketamine (MLK CRI): a well-established combination providing balanced intraoperative analgesia with reduced inhalant requirements
• Fentanyl CRI: an opioid CRI providing titratable intraoperative analgesia

Regional analgesia (nerve blocks)

Nerve blocks have become a key component of TPLO anesthesia because they provide superior post-operative pain control compared to systemic opioids alone.

Femoral and sciatic nerve blocks (FSNB): block the main sensory nerves to the stifle joint and hind limb. Performed before surgery with bupivacaine. PMC research comparing nerve blockade approaches for TPLO confirms that femoral and sciatic nerve blocks provide superior postoperative analgesia compared to IV CRI alone.

Lumbosacral epidural: injection of morphine and bupivacaine into the epidural space. PMC data (epidural + liposomal bupivacaine study) found epidural analgesia produced 36% fewer post-operative opioid injections compared to no epidural.

Intra-articular injection: bupivacaine injected directly into the stifle joint before or after surgery. Used as an alternative or supplement to nerve blocks in some protocols.

Intraoperative monitoring

Standard TPLO monitoring includes:

• ECG: continuous heart rate and rhythm monitoring
• Pulse oximetry (SpO2): peripheral oxygen saturation
• Capnography (end-tidal CO2): assesses ventilation adequacy; dogs are often placed on mechanical ventilation during TPLO
• Blood pressure: direct arterial or indirect Doppler/oscillometric
• Temperature: hypothermia is a common complication of long anesthetic events; warming devices are used routinely
• Depth of anesthesia assessment: clinical signs including eye position, jaw tone, and response to surgical stimulation

Post-operative pain management

TPLO is a significant orthopedic procedure and post-operative pain management directly affects recovery quality and rate of return to function.

NSAIDs: meloxicam or carprofen are administered in the peri-operative period and continued at home for 7 to 14 days minimum. The PMC opioid-free protocol administered meloxicam 0.2 mg/kg IV intraoperatively.

Opioids: hydromorphone or buprenorphine for 24 to 48 hours post-operatively, reducing as the nerve block wears off and NSAID analgesia covers the residual pain.

Gabapentin: increasingly prescribed for the first 1 to 2 weeks post-operatively to address neuropathic pain components associated with the surgical trauma and healing nerve tissues.

For the full recovery guide and what to expect after waking up, see what to expect after TPLO surgery in dogs.

For the leg shaking guide that often relates to anesthetic recovery, see dog leg shaking after TPLO surgery.

For the incontinence guide related to catheterization and anesthesia effects, see dog incontinence after TPLO surgery. For the post-surgical pain guide, see dog whining after TPLO surgery: causes and care.

Frequently asked questions

Is TPLO anesthesia safe for dogs?

For healthy adult dogs, TPLO anesthesia is considered low-risk. The most significant risks involve cardiovascular depression from the anesthetic agents and hypothermia during the procedure.

These are managed through continuous monitoring and supportive care. Pre-anesthetic blood work identifies dogs with conditions that increase risk.

How long is the dog under anesthesia for TPLO?

Total anesthesia time typically ranges from 1.5 to 2.5 hours for a standard TPLO, depending on the surgeon's experience and any complications.

Dogs are usually extubated within 15 to 30 minutes of the end of surgery as they recover consciousness.

What happens if my dog is in pain when it wakes up from TPLO?

Post-operative pain assessment is performed by the veterinary team as the dog recovers. Rescue analgesia (additional opioid doses) is given if pain scores exceed defined thresholds.

The goal of the multimodal protocol is to prevent pain peaks rather than treat pain after it occurs.

Contact the surgical team if your dog appears to be in significant pain after discharge.

My dog is older. Is anesthesia more dangerous?

Age increases anesthetic risk because older dogs are more likely to have subclinical cardiac, renal, or hepatic disease, slower drug metabolism, and reduced physiological reserve.

Thorough pre-anesthetic bloodwork and cardiac assessment (chest X-ray, echocardiogram in selected cases) helps quantify risk. The anesthetic team adjusts protocols for older patients with reduced drug doses and enhanced monitoring.

What does fasting before TPLO mean?

Food is typically withheld for 8 to 12 hours before anesthesia to reduce the risk of vomiting and aspiration during induction or recovery.

Water restriction is typically shorter often until the night before or only 2 to 4 hours before surgery.

Follow your surgeon's specific instructions, which are tailored to your dog's size and health status.

Resources

• PMC. Postoperative Opioid-Free Analgesia in Dogs Undergoing TPLO: A Feasibility Study. pmc.ncbi.nlm.nih.gov
• PMC. Incidence of Postoperative Opioids in TPLO Dogs After Liposomal Bupivacaine With or Without Morphine Epidural. ncbi.nlm.nih.gov
• PubMed. Comparison of Perioperative Analgesic Protocols for Dogs Undergoing TPLO. pubmed.ncbi.nlm.nih.gov
• PMC. Effects of Saphenous and Sciatic Nerve Blocks, Lumbosacral Epidural or MLK CRI on Postoperative Pain in TPLO Dogs. pmc.ncbi.nlm.nih.gov
• VCA Animal Hospitals. Tibial Plateau Leveling Osteotomy (TPLO) in Dogs. vcahospitals.com

Staphylococcus species are the most common cause of surgical site infections (SSI) after TPLO surgery in dogs.

The primary culprit is Staphylococcus pseudintermedius -- a bacterium that normally lives on the skin, nares, and perianal area of healthy dogs.

Understanding why this organism is so prevalent, how it produces infection, and what makes methicillin-resistant strains particularly challenging is essential for owners of TPLO dogs and the veterinary professionals treating them.

Quick answer: S. pseudintermedius is the most common cause of post-TPLO infection. MRSP accounted for 28% of infections in a 659-TPLO study. Signs include redness, swelling, warmth, and discharge -- or only lameness regression and plate-site swelling for deep implant infections. Culture and sensitivity testing is required; empirical treatment risks selecting for further resistance.

Key takeaways

• S. pseudintermedius is the most frequently identified pathogen in TPLO infections: a normal skin commensal in dogs; the PMC 769-TPLO study identified it in 37 of 65 SSI cases
• MRSP accounted for 28% of infections in a 659-TPLO study: a high proportion of resistant organisms in a single surgical population; MRSP does not respond to many first-line antibiotics
• Biofilm formation on the TPLO plate makes staph infections difficult to treat: once established on the metal plate, bacteria are protected from antibiotics; deep implant infections often require plate removal
• Signs of staph infection range from visible wound changes to none: superficial infections produce redness, warmth, and discharge; implant infections may show only lameness regression and plate-site swelling
• Diagnosis requires bacterial culture and sensitivity testing: MRSP cannot be diagnosed visually; empirical antibiotic treatment without culture risks selecting for further resistance
• Pre-operative MRSP carriage significantly increases SSI risk: preoperative MRSP colonization is an independent risk factor; dogs with known carriage require enhanced perioperative protocol

Why S. pseudintermedius is so prevalent in TPLO SSI

It is a normal resident of dog skin

S. pseudintermedius colonizes the skin, nares, and perianal area of most dogs as part of their normal flora. It is present on the surgical preparation area even after antiseptic skin preparation.

The preparation reduces the bacterial load but does not sterilize the skin.

SustainableVet.org confirms: S. pseudintermedius is naturally found on a dog's skin; in healthy dogs it rarely causes issues, but after TPLO surgery it can infect the surgical incision and implants.

The TPLO plate provides a preferred colonization surface

Metal implants dramatically lower the minimum infective dose -- the number of bacteria required to establish infection. On a plate surface, S. pseudintermedius can form biofilm with far fewer organisms than required to infect soft tissue alone.

SustainableVet.org confirms: TPLO surgeries are particularly prone to infection because of the metal implants, which provide a surface for bacteria to stick to and form biofilms.

Licking introduces oral cavity organisms to the incision

The oral cavity of dogs is also colonized with S. pseudintermedius. When a dog licks the incision, it introduces additional bacteria directly to the wound.

This is the most common mechanism of avoidable post-TPLO SSI.

ResearchGate MRSA TPLO case report confirms: the dog licked the surgical site, causing dehiscence, and MRSA was detected from the purulent discharge. This underscores the critical importance of e-collar compliance.

MRSP: the resistant strain that complicates treatment

MRSP (methicillin-resistant Staphylococcus pseudintermedius) is resistant to beta-lactam antibiotics via the mecA gene -- the same mechanism as MRSA in humans. Cephalexin, amoxicillin-clavulanate, and most penicillins are ineffective.

Why MRSP is a particular challenge in TPLO

Most perioperative antibiotic protocols use cefazolin (a cephalosporin). MRSP is resistant to cephalosporins by definition.

If a dog unknowingly colonized with MRSP receives cefazolin prophylaxis, the MRSP is not suppressed. If it reaches the plate, it establishes infection against which standard first-line antibiotics are ineffective.

SustainableVet.org confirms: MRSP has developed resistance to many commonly used antibiotics, making infections harder to treat and increasing the risk of complications.

MRSP incidence in TPLO infections

ResearchGate TPLO MRSA/MRSP study (659 TPLO procedures, SSI rate 11%): MRSP accounted for 20 of 71 infections (28%). This is a high proportion of resistant organisms in a post-surgical population.

Antibiotic options for MRSP

First-line options for susceptible S. pseudintermedius (cephalexin, amoxicillin-clavulanate) do not work for MRSP. Culture and sensitivity testing is required to identify effective agents. Common options based on sensitivity results include:

• Chloramphenicol: effective against many MRSP; requires bone marrow monitoring
• Clindamycin: effective if sensitivity confirmed; not all MRSP strains
• Doxycycline: bacteriostatic; used for some superficial MRSP infections
• Rifampin (rifampicin): excellent biofilm penetration; always combined with another agent to prevent resistance; used for implant-associated MRSP
• Vancomycin: last resort; the MRSA TPLO case report describes a rifampin-vancomycin combination resolving MRSA infection that persisted despite implant removal and vancomycin alone

SustainableVet.org confirms: one of the biggest challenges in treating staph infections after TPLO is the presence of multidrug-resistant bacteria, particularly MRSP; this strain has developed resistance to many commonly used antibiotics.

Signs of post-TPLO staph infection

Superficial incisional infection (SSI-S)

• Redness spreading beyond the incision line (after day 5)
• Warmth at the incision site increasing rather than decreasing
• Swelling that is not resolving or is increasing
• Discharge: cloudy, yellow, green, or malodorous from the incision
• Wound edges that are not healing or are separating

Deep implant-associated infection (SSI-D)

• New or worsening lameness after a period of improvement
• Swelling over the plate site (not necessarily at the incision)
• Warmth specifically at the plate site on palpation
• A draining tract opening near but not at the incision (typically weeks to months post-surgery)
• No discharge from the original incision despite significant clinical signs

SustainableVet.org confirms: signs of infection include redness, swelling, warmth around the incision, pus-like discharge, an unpleasant odor, and increased pain or tenderness.

Diagnosis

Wound swab culture: taken from discharge at the incision or from the draining tract. Provides the organism identification and sensitivity profile.

Deep tissue culture: more accurate than wound swabs because it avoids surface contamination. Obtained at surgery (arthrotomy or plate removal).

Plate surface culture: the most sensitive diagnostic for implant-associated infection. Obtained when the plate is removed.

Imaging: radiographs assess peri-implant bone changes (radiolucent halos, periosteal reaction); advanced imaging (CT) may be used for complex deep infections.

The PMC 769-TPLO study confirmed: bacterial culture was positive in 72% of samples submitted when SSI was first suspected.

Treatment

Superficial infection: culture-directed oral antibiotics for 2 to 4 weeks; wound cleaning; e-collar compliance to prevent licking; local wound care.

Deep implant-associated infection: surgical debridement (lavage and debridement of the plate site); culture; culture-directed antibiotics for 4 to 8 weeks; plate retention if the osteotomy is not yet healed (with the understanding that complete resolution may require later plate removal); plate removal once the osteotomy has healed.

MRSP-specific: culture results guide antibiotic selection. Rifampin combinations are used for biofilm-associated implant infections. Veterinary infectious disease consultation is appropriate for complex MRSP cases.

For the infection prevention guide, see how can TPLO infections be prevented post-operatively?. For MRSP specifically, see can MRSP or MRSA occur after TPLO surgery?.

For the SSI rate data, see how common are infections after TPLO surgery?. For the antibiotic guide, see antibiotics commonly used for TPLO infections.

Frequently asked questions

My dog had a culture and it came back as S. pseudintermedius. Is that MRSP?

Not necessarily. S. pseudintermedius can be methicillin-susceptible (MSSP) or methicillin-resistant (MRSP). The sensitivity panel on the culture report will indicate whether the organism is susceptible to cephalexin and other beta-lactam antibiotics.

If susceptible, it is MSSP and responds to standard first-line drugs. If resistant to cephalosporins, it is MRSP and requires second-line agents.

Can I prevent staph infection after TPLO?

Licking prevention (e-collar compliance for 10 to 14 days) is the single most impactful owner-controlled prevention measure. Licking is the most common avoidable cause of post-TPLO SSI.

Wound dryness, clean bedding, limited environmental contamination, and daily wound inspection are additional preventive measures.

My dog finished the antibiotic course but the discharge came back. What does that mean?

Recurrence after antibiotic completion most commonly indicates biofilm-associated implant infection that was suppressed but not eradicated by antibiotics. Plate removal is likely needed for definitive resolution.

Contact your vet immediately -- do not wait to see if it resolves again.

Can my dog spread MRSP to other dogs or people?

MRSP is primarily a veterinary pathogen. It is less commonly transmitted to humans than MRSA, but zoonotic transmission has been documented.

Standard hygiene measures (hand washing after wound care, gloves for wound dressing changes, avoiding face contact with the infected wound) are appropriate precautions during treatment.

How long does it take to clear a deep staph infection after TPLO?

Deep implant-associated infections typically require 4 to 8 weeks of culture-directed antibiotics plus plate removal once the osteotomy is healed.

MRSP infections that involve biofilm and require rifampin combinations may take 3 to 6 months of total treatment. Osteomyelitis extends this further.

Long courses are necessary because biofilm-associated bacteria are protected from antibiotics and resistant populations can regrow when treatment stops.

Resources

• PMC. Surgical Site Infection After 769 TPLOs. pmc.ncbi.nlm.nih.gov
• ResearchGate. Treatment of MRSA Infection Following TPLO in a Dog. researchgate.net
• SustainableVet. Staph Infection After TPLO Surgery. sustainablevet.org
• SustainableVet. Is Staph the Most Common Infection After TPLO Surgery? sustainablevet.org

Many owners are surprised to find their dog's ankle swollen after TPLO surgery especially when the surgery was performed on the knee, which is well above the ankle.

This gravity-dependent swelling is one of the most common post-TPLO findings, and in most cases it is a completely normal part of recovery.

Knowing what causes it, when it is expected, and when it becomes a reason to call your vet puts you in a much better position during recovery.

Quick answer: Ankle swelling 3 to 5 days post-TPLO is normal — gravity pools post-surgical fluid at the ankle. Resolves in 1 to 2 weeks with rest and cold packing. Call your vet if swelling is hot, fast-growing, or discharging.

Key takeaways

• Ankle swelling at 3 to 5 days post-TPLO is normal: fluid from the knee surgical site tracks down the leg; TPLO Info confirms this is routine
• Gravity pulls fluid to the ankle: dogs do not elevate the leg during recovery, so post-surgical fluid migrates downward
• Normal ankle swelling is mild, soft, and non-painful: not hot, red, rapidly growing, or producing any discharge
• Cold packing and gentle massage help resolve ankle swelling: they reduce inflammation and encourage fluid movement
• Excessive activity worsens ankle swelling: running, jumping, or sustained weight-bearing beyond short leash walks increases fluid accumulation
• Infection is the main abnormal cause: infected swelling is warm, painful, and accompanied by fever or lethargy

Why does ankle swelling happen after TPLO?

TPLO surgery is performed at the proximal tibia just below the knee. However, the inflammatory response and fluid production that result from surgery are not confined to the exact surgical site.

Gravity-dependent fluid migration: post-surgical serum and inflammatory fluid produced at the knee level migrate downward along tissue planes. Because dogs do not elevate their legs during recovery unlike a human keeping a leg raised on a pillow this fluid pools in the lower leg and ankle region.

TPLO Info confirms ankle swelling at 3 to 5 days post-TPLO is completely normal and recommends massage and icing if this occurs.

Lymphatic disruption: the surgery disrupts local lymphatic vessels that normally drain fluid from the lower leg. Until these pathways regenerate or compensate, fluid accumulation in the lower leg is common.

Reduced movement: when a dog is resting with the leg dependent (hanging down), fluid accumulates. Brief controlled leash walks stimulate the lymphatic pump and muscle contractions that help move fluid back up the leg.

Normal ankle swelling: what to expect

Normal post-TPLO ankle swelling typically:

• Appears at day 3 to 5 post-surgery
• Is soft and pitting (you can press on it and it indents temporarily)
• Is not warm to the touch
• Does not produce any discharge
• Does not cause significant additional pain beyond the expected post-operative discomfort
• Gradually reduces over 1 to 2 weeks with rest and activity restriction

VCA Animal Hospitals notes that mild to moderate swelling is expected after TPLO surgery as the body responds to tissue trauma and the healing process begins.

Abnormal ankle swelling: warning signs

Contact your veterinarian if you observe:

• Swelling that is rapidly increasing especially in the first 1 to 2 weeks
• Warmth or heat in the swollen area beyond mild
• Redness or skin discoloration around the ankle or lower leg
• Discharge or pus from the surgical incision or surrounding skin
• Your dog refusing to bear any weight on the leg
• Fever, lethargy, or loss of appetite alongside the swelling
• Swelling that is growing rather than shrinking after the first week

These signs suggest infection, hematoma, or a complication beyond normal gravity-dependent fluid pooling.

How to manage ankle swelling at home

Cold packing: apply a cold pack (frozen peas wrapped in a thin towel) to the ankle for 10 to 15 minutes, 2 to 3 times daily. Cold reduces local inflammation and provides mild pain relief. Always wrap the cold pack never apply ice directly to skin.

Gentle massage: TPLO Info recommends gentle massage if ankle swelling develops. Using a light hand, massage from the ankle upward toward the knee to encourage fluid to move back toward the body. Do not massage the surgical incision site itself.

Activity restriction: the most important intervention. Every unnecessary step the dog takes increases fluid production and worsens swelling. Strict confinement with leash-only bathroom walks is essential for the first 6 to 8 weeks.

Short controlled leash walks: paradoxically, very short leash walks (5 to 10 minutes) are better than complete immobility. Gentle controlled movement stimulates the lymphatic pump and helps clear fluid more effectively than prolonged rest. Do not allow the dog to run, jump, or play.

Timeline: when should ankle swelling resolve?

Most normal ankle swelling resolves within 1 to 2 weeks of surgery when activity restriction is maintained.

Vetplayas notes that swelling is a common response to surgical intervention and typically improves as healing progresses.

Persistent ankle swelling beyond 2 to 3 weeks, or swelling that worsens rather than improves, warrants a veterinary recheck.

This may indicate a seroma has formed in the lower leg, or that the dog is more active than recommended.

For the full fluid buildup and seroma guide, see fluid buildup after TPLO surgery in dogs.

For the full swelling timeline and duration guide, see how long does swelling last after TPLO surgery. For the complete complications overview, see 15 common complications after TPLO surgery in dogs.

For the incision infection guide, see TPLO incision infection symptoms and prevention.

Frequently asked questions

Is ankle swelling after TPLO always from the surgery?

In the first 1 to 3 weeks post-surgery, yes ankle swelling almost always relates directly to the procedure.

Rarely, a dog might develop an unrelated issue (insect sting, foreign body, contact dermatitis) but the timing overwhelmingly points to post-surgical fluid migration in most cases.

Should I wrap my dog's ankle if it's swollen after TPLO?

Only if your vet specifically recommends it. Improper bandaging can cut off circulation or cause pressure sores.

If you are concerned about the ankle swelling, contact your vet before applying any bandage or wrap at home.

My dog's ankle is swollen but the knee looks fine. Is that normal?

Yes. The surgical site at the knee may look relatively normal while the ankle is more visibly swollen because gravity pulls fluid downward.

This pattern is completely consistent with normal post-TPLO fluid migration and is not a sign that something is wrong at the ankle itself.

Can I use a compression sock on my dog's ankle?

Not without veterinary guidance. Human compression garments are not designed for canine anatomy and can cause pressure injury, especially around the hock joint.

If compression is indicated, your vet will apply an appropriate veterinary bandage.

When should I take my dog back to the vet for ankle swelling?

If the swelling appears within the first 1 to 2 weeks and is mild, soft, and not causing distress monitor at home with cold packing and massage.

If it is growing, warm, accompanied by redness or discharge, or if your dog is in significant pain, contact your vet promptly rather than waiting for a scheduled recheck.

Resources

• TPLO Info. Recovery FAQs. tploinfo.com
• VCA Animal Hospitals. Tibial Plateau Leveling Osteotomy (TPLO) in Dogs. vcahospitals.com
• Vetplayas. Understanding Swelling After TPLO Surgery. vetplayas.com
• Midwest Veterinary Specialists. Post-Operative Care Following TPLO. midwestveterinaryspecialists.com

A clicking or popping sound from the stifle after TPLO surgery is a common observation that owners report, especially during the first weeks of recovery.

It is not automatically a sign of a problem.

The clinical significance depends on what accompanies the click: is the dog bearing weight and recovering normally, or is clicking associated with lameness, pain, or a trajectory reversal?

Quick answer: Post-TPLO clicking most often reflects normal joint adjustment, soft tissue movement, or cavitation. The most clinically important cause is a meniscal tear, producing a meniscal click with pain and returning lameness. Clicking without lameness or pain in early recovery is usually benign.

Key takeaways

• Most post-TPLO clicking is benign: the click typically comes from joint adjustment to new mechanics; the dog usually feels fine even when a sound is present
• The meniscal click is the clinically significant type: dogs with meniscal tears exhibit a meniscal click accompanied by lameness and pain
• Clicking with lameness or pain warrants prompt veterinary evaluation: clicking with swelling, limping, or avoiding the leg could signal instability, implant issues, or a torn meniscus
• Clicking that is isolated, early in recovery, and not associated with lameness is usually normal and improves as healing progresses
• Late-onset clicking in a previously normal recovery is more concerning than early clicking; it suggests a new event such as meniscal tear or implant loosening
• Implant loosening is a rare but serious cause of clicking: abnormal joint mechanics from loosened screws or plate produce clicking accompanied by pain and radiographic changes

What causes clicking after TPLO surgery

Normal joint adjustment

After TPLO, the tibial plateau is repositioned to a new angle. The soft tissues, tendons, and joint capsule require weeks to adapt to this new geometry.

During this adaptation period, movement can produce audible sounds as structures slide over each other or snap slightly over new contours.

TPLO Info confirms: after CCL repair, the joints adjust to new motion. The click comes from the knees. The dog usually feels fine even when a sound is present.

Soft tissue movement over the implant

The TPLO plate sits against the medial tibial surface. Tendons and fascial layers that previously moved over the normal tibial contour now move over a plate with a different profile.

This can produce audible snapping or clicking sounds during flexion and extension, particularly in the first weeks before soft tissue accommodation occurs.

Gas bubble release (cavitation)

Joint capsule distension from post-surgical effusion can trap gas in the joint space. Movement releases this gas in small pops -- the same mechanism as knuckle cracking in humans.

This is painless and harmless.

Meniscal click (most significant cause)

The medial meniscus is vulnerable to injury in CCL disease. At the time of TPLO, the surgeon assesses the meniscus and removes damaged tissue.

However, meniscal injury can occur after TPLO -- either from previously undetected damage that progresses, or from new injury in a joint that has not yet fully stabilized.

Laguna Woods Vets confirms: dogs with meniscal tears frequently exhibit a meniscal click. If damage is noted during TPLO, the meniscus is removed. If not removed, it may tear later.

SustainableVet.org confirms: symptoms of meniscal damage include clicking when the dog moves, lameness, reluctance to use the affected leg, and discomfort when bending the knee.

The meniscal click is distinguished from benign clicking by:

• Accompanying lameness (often a sudden return of limping after initial improvement)
• Pain when the stifle is manipulated on examination
• Worsening trajectory rather than improvement

Implant-related clicking (uncommon)

Plate or screw loosening generates abnormal tibial motion during weight bearing, which can produce clicking.

This is uncommon in an uncomplicated TPLO but more likely if the dog has been overactive during recovery.

Signs include pain localized to the plate site and radiographic evidence of implant migration or peri-implant bone changes.

SustainableVet.org confirms: implant failure is rare but serious; plates or screws can loosen or break if the dog is too active early, leading to discomfort and joint noises.

Normal vs. concerning clicking: a practical guide

Likely normal (benign):

• Clicking present from the first days after surgery
• No lameness associated with the click
• Dog is bearing weight and improving week by week
• Click is quiet and intermittent
• Dog does not react (wince, pull back, vocalize) when the stifle is manipulated

Warrants veterinary evaluation:

• Clicking that appears new after a period of recovery without clicking
• Clicking accompanied by lameness or reluctance to bear weight
• Dog flinches or vocalizes when the stifle is flexed
• Clicking that is getting louder or more frequent over time
• Lameness that had been improving and then reverses

SustainableVet.org confirms: contact your vet if the clicking sound is persistent or getting worse over time; a mild clicking early in recovery is normal but it should improve as healing progresses.

Meniscal tear after TPLO: what happens next

If a meniscal tear is suspected or confirmed, management depends on severity.

Mild cases: pain management with NSAIDs, joint supplements, and controlled exercise restriction. The meniscus may stabilize with conservative management if the tear is small and the joint is otherwise stable.

Cases with ongoing pain or lameness: partial meniscectomy (surgical removal of the torn portion of the meniscus) is required. This is a second surgical procedure requiring general anesthesia and a repeat recovery period.

SustainableVet.org confirms: if a meniscal tear causes ongoing pain and instability, surgery is often needed; this may involve a partial meniscectomy.

Larger dogs and clicking

Larger dogs are more likely to produce audible joint sounds during recovery. Greater body mass means greater joint loading forces, which amplify soft tissue and implant movement sounds.

SustainableVet.org confirms: larger dogs are more likely to make joint sounds during recovery; their extra weight puts more pressure on the healing leg, which can make clicking more noticeable.

This does not mean clicking in large dogs is more likely to be pathological -- only that it is more audible when it occurs.

When to contact your vet about clicking

Contact your vet promptly (same day or within 24 hours) if:

• Clicking is accompanied by lameness or non-weight bearing
• A dog that was improving begins to worsen (trajectory reversal)
• The click is producing a visible pain response
• The click appears late in recovery (after weeks of silent healing)

Contact at your next scheduled appointment (can wait):

• Intermittent clicking early in recovery without lameness
• Click that is quieter week by week
• Dog is bearing full weight and improving in function

For the full TPLO complications guide, see common complications after TPLO surgery. For the toe-tapping guide, see dog toe tapping after TPLO surgery.

For the lameness guide, see lameness after TPLO surgery in dogs. For the leg shaking guide, see dog leg shaking after TPLO surgery.

Frequently asked questions

My dog's knee has been clicking for 3 weeks but she is not limping at all. Should I be worried?

Three weeks of clicking with no lameness and a normal, improving recovery trajectory is most likely benign joint adjustment. Monitor for lameness, pain on stifle palpation, or worsening of the click.

Mention it at your next scheduled vet appointment -- this is not an emergency call.

My dog's leg clicked once loudly while getting up, and then she held the leg up. What do I do?

Contact your vet the same day. A sudden loud click followed by acute lameness may indicate a meniscal injury event. This presentation warrants veterinary examination and likely radiographs.

Can clicking after TPLO get better on its own?

Yes -- benign mechanical clicking from joint adjustment and soft tissue accommodation typically resolves or reduces significantly over the first 4 to 8 weeks.

A meniscal click does not resolve without treatment of the meniscal tear.

Does clicking mean the plate is failing?

Not typically. Implant failure clicking is accompanied by pain and worsening lameness. Benign clicking in a comfortable, normally-recovering dog does not indicate implant failure.

Radiographs at the scheduled 6-week and 12-week appointments assess implant integrity.

My dog clicks on every step. Is that different from occasional clicking?

Consistent clicking on every step, particularly if it has a regular, reproducible pattern during weight bearing, is more likely to have a structural cause (meniscal click) than intermittent clicking.

Mention this to your vet and assess whether lameness is present.

Resources

• TPLO Info. Why Is My Dog's Leg Clicking After TPLO Surgery? tploinfo.com
• SustainableVet. Why Is My Dog's Leg Clicking After TPLO Surgery? sustainablevet.org
• Laguna Woods Vets (LHAH). TPLO Surgery Complications. lhah.com
• ACVS. Cranial Cruciate Ligament Disease. acvs.org