In the absence of trauma, a dog's legs suddenly become lame for several reasons: foot pad injury, calcium deficiency, arthritis, or damage to the nervous system.

1. Injury to the foot pads: If the dog's foot pads are injured by stones or wooden thorns, the dog is likely to limp due to pain. The owner should carefully check and pull out the foreign body, clean and disinfect the dog's wound with saline and alcohol, apply medicine and bandage, and reduce outdoor activities until the wound heals to avoid further injury.

2. Calcium deficiency: During the growth and development of dogs, if the dog eats a single diet, it is likely to be lame due to calcium deficiency due to unbalanced nutrition. Pet owners should pay attention to strengthen the dietary nutrition management of dogs and do a good job in calcium supplementation. They can supplement high-calcium foods such as dried shrimps, kelp, beans, etc. on the basis of feeding high-quality dog ​​food with comprehensive nutrition, and can also take it together. Calcium powder or tablets for dogs can help restore normal calcium levels.

3. Arthritis: Dogs that are old, obese or have been exercising excessively for a long time may have joint wear and aging problems, and arthritis can lead to lameness. In the early stage, it is necessary to supplement calcium, control weight, and strictly regulate the amount of exercise. In severe cases, surgery or acupuncture is required for treatment.

4. Nervous system damage: Drug abuse and improper injection of vaccines may damage the dog's nervous system, and the legs cannot be effectively controlled, resulting in lameness.