Flat feet in dogs results primarily from genetic predisposition or trauma. The first condition is known as carpal subluxation, while the second is referred to as carpal hyperextension. Treatment for flat feet includes medication, splinting of the affected legs or surgery, all depending on the severity of the condition.
In the canine leg, the carpus is similar to the human wrist. In a dog suffering from carpal subluxation, this joint is dislocated. Over time, the dog starts to walk on the dislocated carpus, looking like he has flat feet. Walking on the joint causes tendon swelling and hardening of the ligaments. Carpal subluxation occurs more often in males than females, and in certain breeds. These include Labrador retrievers, Irish setters, Doberman pinschers, Shar-Peis and German shepherds.
Problems in Puppies
Puppies affected by carpal issues usually show signs between the ages of 6 to 12 weeks, although symptoms can appear later. While the pup isn't in pain, he might have trouble walking. In less serious cases, treatment consists of injecting steroids into the tendon sheath on the affected legs, with additional shots a few weeks later. Severe cases require surgery on the tendon sheath. While this might allow the tendons to move freely, it can cause early onset arthritis in the dog.
Carpal hyperextension usually results from an accident or fall, such as jumping from a substantial height. Immediate lameness generally occurs, along with carpal swelling and the flat-footed appearance of walking on the carpal joint. Take your dog to the emergency vet if he exhibits carpal hyperextension symptoms. The vet must take X-rays of the affected leg, with further X-rays necessary if other trauma is suspected. While pain management and splinting the leg can help, it's likely your dog will require surgery and an extended period of recuperation. He might not regain much, if any, range of motion in his carpus after recovery. However, surgery will allow him a more normal, pain-free gait in the long term.
Preventing Carpal Hyperextension
Prevention is always worth a pound of cure -- or the thousands of dollars you might spend treating a carpal hyperextension injury. Since falls cause the majority of carpal hyperextension injuries, keep windows and doors in upper level parts of your home secured and dog-proof. If you have a steep staircase in your home, limit your dog's access to the upper floor. When taking your dog out for a run, avoid steep slopes, embankments and uneven ground.
- University of Sydney: Disorder -- Carpal Subluxation
- Love My Pet: Carpal and Pedal Lameness in the Dog
- The Canadian Veterinary Journal: Canine Carpal Conundrums
- Pet Place: Carpal Hyperextension in Dogs
- Veterinary Specialty Center of Tucson: Surgery – Carpal Hyperextension Injury
- Grunfeld German Shepherds: Carpal Subluxation and Weak Pasterns -- Two Different Conditions?