Veterinary Guide
Dog Knee Arthritis (Stifle Joint)
The knee is the most commonly treated joint in veterinary orthopaedics. Understanding the causes of knee arthritis is the first step to effective management.
Understanding the Dog Knee
The dog's knee, technically called the stifle joint, is the most complex joint in the body and the one most frequently affected by disease. It consists of the femur (thigh bone), tibia (shin bone), and patella (kneecap), held together by two cruciate ligaments, two meniscal pads, and a joint capsule. When any of these structures is damaged, arthritis follows.
Cruciate ligament disease alone accounts for an estimated $1.32 billion per year in veterinary treatment costs worldwide. In Australia, cruciate surgery (TPLO or TTA) typically costs $3,500-$6,500 per knee — and many dogs eventually need both knees treated. This makes knee arthritis not just a health concern but a significant financial one for dog owners.
Regardless of the initial cause — cruciate tear, patella luxation, OCD, or meniscal injury — once the knee joint is damaged, arthritis is inevitable. The goal of treatment is to slow progression, manage pain, maintain mobility, and preserve quality of life. Green-lipped mussel supplements like Joint Rejuvenate play an important role in this management, both before and after surgery.
Four Causes of Knee Arthritis in Dogs
Each cause requires a different treatment approach, but all lead to the same outcome: progressive osteoarthritis of the stifle joint.
Cranial Cruciate Ligament (CCL) Disease
Most CommonThe cruciate ligament stabilises the knee by preventing the tibia (shin bone) from sliding forward under the femur (thigh bone). In dogs, this ligament degenerates over time rather than rupturing in a single traumatic event (unlike ACL injuries in humans). Once the ligament weakens or tears, the knee becomes unstable, and arthritis develops rapidly.
Most Affected Breeds
Labrador Retriever, Rottweiler, Newfoundland, Staffordshire Bull Terrier, Golden Retriever, Bulldog
Surgical Options
TPLO (Tibial Plateau Levelling Osteotomy) or TTA (Tibial Tuberosity Advancement) is recommended for dogs over 15kg. Success rate: 85-95%.
Patella Luxation
Very CommonThe patella (kneecap) dislocates from its groove in the femur, usually medially (inwards). Ranges from Grade 1 (manually dislocatable, pops back) to Grade 4 (permanently dislocated). Grades 1-2 cause intermittent lameness and cartilage wear. Grades 3-4 cause chronic pain and arthritis.
Most Affected Breeds
Cavalier King Charles, Pomeranian, Yorkshire Terrier, Chihuahua, Pug, French Bulldog
Surgical Options
Surgical correction (trochleoplasty + tibial crest transposition) recommended for Grades 3-4 and symptomatic Grade 2.
Osteochondritis Dissecans (OCD)
UncommonA developmental condition where a flap of cartilage separates from the underlying bone in the stifle joint. Usually appears between 4-8 months of age in large breeds. The loose cartilage flap causes inflammation, pain, and mechanical damage to the joint surface, leading to early-onset arthritis.
Most Affected Breeds
Great Dane, Labrador Retriever, Rottweiler, Golden Retriever, Bernese Mountain Dog
Surgical Options
Arthroscopic removal of the cartilage flap. Prognosis is good if treated early, though some arthritis is inevitable.
Meniscal Injury
Common (Secondary)The menisci are C-shaped cartilage pads that cushion the knee joint. They are commonly damaged secondary to cruciate disease — when the tibia slides forward, it crushes the medial meniscus. Approximately 40-60% of dogs with cruciate tears also have meniscal damage. Meniscal tears cause a distinctive clicking sound and worsen arthritis progression.
Most Affected Breeds
Any breed with cruciate disease (same risk profile)
Surgical Options
Damaged meniscus is partially or fully removed during cruciate surgery. Dogs without a meniscus have reduced shock absorption and faster arthritis progression.
Signs Specific to Knee Arthritis
Knee arthritis produces distinctive signs that differ from hip or elbow disease. Knowing what to look for helps with early detection.
Bunny-hopping (both back legs moving together)
This is the hallmark of bilateral knee disease — both knees affected simultaneously. The dog avoids putting weight on either knee individually by hopping with both together. Up to 60% of dogs with cruciate disease in one knee will develop it in the other within 1-2 years.
Sitting with the leg kicked out to the side (“lazy sit”)
A dog with knee arthritis cannot comfortably flex the affected knee into a normal sitting position. They compensate by extending the leg to the side. This is one of the earliest signs and is often dismissed as a quirky habit.
Toe-touching lameness after rest
The dog briefly touches the affected paw to the ground but does not bear weight on it for the first few steps after getting up. After warming up (30-60 seconds of walking), they may appear normal. This is classic for early cruciate disease.
Sudden non-weight-bearing lameness
Sudden, severe lameness with the leg held up completely usually indicates a complete cruciate tear or acute meniscal tear. This is a veterinary emergency — see your vet within 24 hours.
Clicking or popping from the knee
An audible click during walking or when the dog stands up usually indicates meniscal damage. The sound comes from the torn meniscus catching and releasing as the joint moves. Always warrants veterinary investigation.
Thickened, swollen knee (“medial buttress”)
Chronic knee arthritis causes thickening of the joint capsule and fibrous tissue buildup on the inside of the knee. You can feel this as a firm, swollen area on the inner aspect of the knee, distinct from the normal bony landmarks. This is called a medial buttress and indicates established arthritis.
Conservative vs Surgical Management
Conservative (Non-Surgical)
Best for: dogs under 15kg, partial tears, patella Grade 1-2
- Strict rest for 6-8 weeks to allow scar tissue stabilisation
- Weight management — lean body condition is critical
- Joint Rejuvenate at treatment dose (40-60mg/kg) for anti-inflammatory and cartilage support
- NSAIDs (meloxicam, carprofen) for pain management during acute phase
- Physiotherapy and hydrotherapy once initial healing occurs
- Custom knee brace (stifle orthotic) for additional stability
- Lifelong exercise modification — no high-impact activities
Surgical (TPLO / TTA)
Best for: dogs over 15kg, complete tears, Grade 3-4 patella
- TPLO or TTA surgery to mechanically stabilise the knee
- 85-95% return to good function with proper rehab
- Cost: $3,500-$6,500 per knee in Australia
- 6-12 week rehabilitation period post-surgery
- Joint Rejuvenate supports recovery and long-term joint health
- Arthritis will still develop but progression is much slower
- 60% risk of needing the other knee done within 2 years
Post-Surgery Rehabilitation Timeline
Recovery from TPLO or TTA surgery follows a structured timeline. Joint Rejuvenate supports healing at every stage.
Weeks 1-2
Strict Rest
Crate or pen rest except for toileting on a lead. Ice the knee 3-4 times daily (10 minutes, wrapped in a towel). Joint Rejuvenate can begin immediately — the anti-inflammatory omega-3s support early healing.
Weeks 3-4
Controlled Movement
Short lead walks of 5 minutes, 3-4 times daily on flat surfaces. Passive range-of-motion exercises (gentle knee bending) as directed by your vet or physiotherapist. Continue Joint Rejuvenate at treatment dose (40mg/kg).
Weeks 5-8
Gradual Increase
Increase walks to 10-15 minutes. Introduce gentle slopes and varied terrain. Begin underwater treadmill or swimming if available — hydrotherapy is ideal at this stage. Maintain supplement dose.
Weeks 9-12
Building Strength
Walks of 20-30 minutes. Off-lead exercise in controlled environments. Swimming 2-3 times per week. The surgical site is healed, but the knee is still remodelling. Continue Joint Rejuvenate — the joint will benefit from ongoing cartilage support as it adapts.
3-6 Months
Return to Activity
Gradually return to near-normal activity levels. Some modifications will be permanent — avoid ball launchers, reduce jumping, maintain lean weight. Transition to prevention dose (20mg/kg) for lifelong joint support.
The Role of Joint Rejuvenate in Knee Arthritis
Whether your dog is managed conservatively or has had surgery, Joint Rejuvenate provides targeted support for the stifle joint. The omega-3 fatty acids from green-lipped mussel reduce the inflammatory cascade that drives cartilage destruction. Glucosamine and chondroitin provide raw materials for cartilage maintenance. Hyaluronic acid restores synovial fluid viscosity, reducing bone-on-bone friction in a joint that has lost its meniscal cushioning.
Joint Rejuvenate is safe to start immediately after surgery — there are no contraindications with post-operative medications including NSAIDs, antibiotics, or opioid pain relief. Dr John Stewart recommends the treatment dose (40-60mg/kg) during the recovery period, stepping down to the prevention dose (20mg/kg) once the dog has returned to normal activity.
For dogs managed conservatively, Joint Rejuvenate is a core part of the treatment plan, not just an add-on. The combination of anti-inflammatory action and cartilage support makes it the ideal supplement for ongoing knee arthritis management.
Support Your Dog's Knee Recovery
Joint Rejuvenate works alongside veterinary treatment to support stifle joint health before and after surgery.