Leg stiffness is not only quite painful, but can also be quite disruptive to normal life. The causes of leg stiffness are quite varied, and can result from conditions as mild as a pulled muscle, or as serious as multiple sclerosis. Other common causes of stiff legs include arthritis and restless leg syndrome. Some causes of stiff legs can be quite serious, so individuals who experience unusual leg stiffness should see their physician as soon as possible in order to ensure rapid diagnosis and treatment. As with many other conditions, the sooner the problem is identified, the better the patient's prognosis.

One of the most common causes of stiff legs is a pulled muscle. Individuals who participate in high amounts of physical activity, such as runners, cyclists, or weight lifters, often experience pulled muscles. In addition, individuals who are very debilitated can also experience a pulled muscle. While this condition can be quite painful, it can usually be remedied through rest and stabilization. In the most severe cases, surgery may be required. Once the pulled muscle is treated, the pain and stiffness associated with it are rapidly alleviated.

Arthritis is another common cause of stiff legs. Individuals who experience severe arthritis in their knees or hips are at risk for the development of stiff legs. Those suffering from this condition are encouraged to participate in light cardiovascular exercise and perform range of motion exercises in order to prevent further joint deterioration. In the most severe cases of arthritis, surgery may be a necessity. While arthritis often occurs in old age, it can also develop in young individuals who put high amounts of stress on certain parts of their body.

Stiff legs have also been linked to restless leg syndrome. Though an compulsion to constantly move the legs is the most common symptom of restless leg syndrome, individuals may also experience stiffness, burning, or itching in the legs. Individuals will often need to use medical and behavioral treatments to overcome restless leg syndrome.

Autoimmune disorders, such as multiple sclerosis, can also be to blame for stiff legs. When these disorders are to blame, leg stiffness is often considered to be progressive in nature, and can be quite difficult to treat in later stages. Individuals whose legs stiffen unexpectedly or whose stiffness remains longer than usual are encouraged to seek medical assistance as soon as possible to identify the cause of the condition.