Why is my shih tzu limping on his back leg?
If your Shih Tzu is limping on a back leg, the most likely culprit is patellar luxation, a knee condition common in small breeds. Other possibilities include hip dysplasia, a torn ACL (cranial cruciate ligament), intervertebral disc disease (IVDD), or a simple injury like a sprain or foreign object stuck in the paw. Because Shih Tzus are prone to certain orthopedic issues, you should consult your veterinarian for an accurate diagnosis. Here’s what you need to know about each cause and what to do next.
Patellar Luxation: The #1 Cause in Shih Tzus
Patellar luxation occurs when the kneecap (patella) slips out of its normal groove. In Shih Tzus, this is often due to shallow grooves or abnormal leg alignment. You might notice your dog suddenly lifting his back leg and then shaking it out to pop the kneecap back in place. Signs include intermittent limping, skipping steps while running, or holding the leg up for a few steps. Most cases are graded from 1 (mild, rare popping out) to 4 (severe, persistent luxation). Mild cases may be managed with weight management, joint supplements (like glucosamine and chondroitin), and physical therapy. Grade 3-4 often requires surgery to deepen the groove and realign the leg. Your vet will perform a physical exam and possibly x-rays to confirm.
Hip Dysplasia: A Genetic Concern
Hip dysplasia is a malformation of the hip joint that causes looseness and arthritis. While more common in large breeds, Shih Tzus can be affected. Symptoms include limping after exercise, difficulty rising, or a bunny-hopping gait. Your vet may diagnose it with a hip palpation (Ortolani test) or x-rays. Treatment ranges from weight control, anti-inflammatory medications, and joint supplements to physical therapy and, in severe cases, surgery (total hip replacement or femoral head ostectomy). Early intervention slows arthritis progression.
Cranial Cruciate Ligament (CCL) Tear
A torn ACL (or CCL in dogs) is another common cause of hind-leg limping. It often happens from a sudden twist or jumping. Symptoms include sudden onset of non-weight-bearing lameness, swelling on the inside of the knee, and difficulty sitting properly. Diagnosis is via a cranial drawer test (performed by your vet). Mild partial tears may heal with strict rest, but full tears typically require surgery (e.g., TPLO or TTA) especially for active dogs. Post-surgery rehab is critical.
Intervertebral Disc Disease (IVDD)
Shih Tzus are a chondrodystrophic breed, meaning they have a high risk of IVDD, where disc material bulges into the spinal cord. While IVDD often affects the back, it can cause hind-leg weakness, limping, or even paralysis. Symptoms include a hunched back, yelping when touched, wobbliness, or dragging a leg. This is a medical emergency. If your dog shows sudden inability to use his back legs or severe pain, go to an emergency vet immediately. Treatment ranges from strict crate rest for mild cases to surgery for severe compression.
Minor Injuries and Foreign Objects
Sometimes limping is from a simple cause like a cut paw pad, broken nail, or a burr stuck between toes. Examine your dog’s leg and paw gently. Look for swelling, bleeding, or an object. If you find a foreign body, you can try to remove it with tweezers (if safe) and clean the area, but always monitor for signs of infection. A sprain or strain from overexertion may resolve with a few days of rest. If limping persists more than 24 hours, see your vet.
When to See a Vet Right Away
Seek immediate veterinary care if your Shih Tzu:
– Cannot or will not put any weight on the leg.
– Has a visibly deformed or swollen joint.
– Shows signs of severe pain (whining, trembling, aggression).
– Has sudden hind-leg paralysis or loss of bladder control (possible IVDD).
– Has an open wound or a foreign object you cannot safely remove.
For mild, intermittent limping, you can rest your dog for 48 hours (no running, jumping, or stairs) and monitor. If limping persists or worsens, schedule a vet appointment. Do not give human painkillers (like ibuprofen) as they are toxic to dogs. Your vet may recommend dog-safe anti-inflammatories, joint supplements, or a treatment plan specific to the diagnosis.
What You Can Do at Home
- Keep your Shih Tzu at a healthy weight to reduce joint stress.
- Provide joint supplements containing glucosamine, chondroitin, and omega-3 fatty acids (consult your vet for the right dose).
- Use non-slip rugs on hard floors to improve traction.
- Limit jumping off furniture; use ramps or steps.
- Apply a warm compress to sore muscles (not to an open wound or hot joint).
- Follow your vet’s instructions for rehabilitation exercises or physical therapy.
Remember, early detection and treatment give the best outcome. Your vet is your partner in keeping your Shih Tzu pain-free and mobile.
Key Takeaway
If your Shih Tzu is limping on a back leg, prioritize a vet visit to diagnose patellar luxation, hip dysplasia, or other issues, and avoid home remedies that may delay necessary treatment.