TL;DR: Sudden non-weight bearing lameness indicates significant pain or injury; you should seek veterinary care within 24 hours, or immediately if there is a visible deformity or severe distress.
What does it mean if my dog suddenly stops putting weight on a leg?
Sudden non-weight bearing lameness occurs when your dog abruptly stops using one of their hind legs, often holding it up entirely. This is a clear sign of significant pain or mechanical instability. Common causes include:
- A torn cranial cruciate ligament (CCL)
- A sharp object stuck in the paw pad
- A fractured bone
- A sudden joint dislocation
Is it an emergency if my dog is suddenly limping and not using their leg?
- Urgency Level: Medium. While a limp is rarely immediately life-threatening, a dog that cannot put weight on a limb is in considerable discomfort.
- You should aim to see a veterinarian within 24 hours for a physical exam.
- Seek emergency care immediately if you notice an obvious deformity or an open wound.
- Seek emergency care if your dog is excessively panting and unable to settle, as they may require immediate pain management and stabilization.
How can a photo or video help my veterinarian triage my dog's lameness?
- A clear photo of the paw or a brief video of your dog trying to move allows a professional to assess the limb's alignment and distress level before you arrive.
- This information helps the clinic determine how quickly your pet needs to be seen.
- Visuals help the veterinary team prepare for the specific diagnostic steps required for your pet's condition.
Clinical Context (Merck Veterinary Manual)
In dogs presenting with sudden non-weight-bearing lameness of a hind limb, common differentials include Achilles tendon rupture and thoracolumbar disc extrusion. Achilles tendon rupture, typically seen in mature working or athletic dogs, presents with severe non-weight-bearing lameness, tarsal hyperflexion, and a plantigrade stance, with palpation revealing swelling, pain, and torn tendon ends; radiographs may show avulsed bone fragments. Thoracolumbar disc extrusion may cause pelvic limb lameness with potential progression to ataxia, paraplegia, and incontinence; neurological deficits are usually more severe than in cervical disc disease, and the presence of deep pain perception caudal to the lesion is an important prognostic indicator.
Chapter: Orthopedics
Source: The Merck Veterinary Manual, 11th Edition (Page 1203)