Lameness is usually the first sign of a dog sprained leg — this indicates your dog is in pain. Swelling may follow. If the leg becomes warm or hot, however, it's unlikely that the limping is due to a simple sprain. If the sprain goes unaddressed, lameness may continue and, over time, leg muscles may weaken. When atrophy occurs in one limb, the opposite limb absorbs additional pressure and stress, putting the otherwise unaffected limb at risk of ligament injury.

Your veterinarian should be able to accurately diagnose the cause of lameness in a single office visit. According to the Merck Veterinary Manual, the vet will likely conduct a lameness exam and may also use imaging such as X-rays and/or MRI. In addition, they may perform blood work to rule out infectious causes of limping, like Lyme disease, and to verify whether your dog is a good candidate for certain medicines.

Because of humans' upright posture, ankles bear the brunt of our weight and walking impact. It's no wonder that sprained ankles are the most common type of sprain among humans. But your dog's weight is distributed differently. The knees of a dog's rear legs absorb the bulk of the stress and pressure of their body weight, making them more predisposed to knee sprains rather than ankle sprains.

Obese dogs are more likely to suffer from ligament injuries such as cranial cruciate ligament injury. By keeping your dog at a healthy weight, you can decrease their chance of developing lameness-associated sprains and injuries. Talk to your veterinarian about nutritional support as well. If your veterinarian determines your dog is obese, they might recommend a therapeutic food to help your dog reach a healthier weight or one that helps with joint and mobility support.

Additionally, because dogs often get most of their sprains from jumping down, consider not allowing them on furniture like couches or beds, or provide them with an easier method for getting down like steps or a ramp.

While a sprain is more serious than a simple strain, most dogs make a full recovery from a sprained leg. The biggest challenge most pet parents face is convincing their active and energetic canine companions to take it easy for the roughly six weeks it takes for a sprain to heal. If it doesn't fully heal, there's a risk of re-injury. Over time, chronic repeated ligament injuries are more likely to require surgery, so remember to follow the vet's orders and do your best to restrict your pet's exercise — even if that means crate rest.