Bone Disorders

• Disorders of the bones of the legs and lower back can be a cause of sharp leg pain, according to the Mayo Clinic. A fractured, bulging or herniated disk in the lower back can cause sudden sharp pains in the leg that can radiate all the way to the toes. Cancer in the bones of the legs and arthritis in the joints of the hip, knee or ankle can also be a cause of sharp leg pains.
  
  

Broken Bones

• According to the Mayo Clinic, broken bones in the leg and foot can be a cause of sharp leg pains. A break in one of the large bones of the leg (tibia, fibula or femur) can cause sudden sharp pains and an inability to bear weight. A stress fracture in a leg or foot bone can also be a cause of sharp leg pains, and both fractures and broken bones require immediate medical attention.
  
  

Circulatory Problems

• According to the National Library of Medicine, certain types of circulatory problems may be a cause of sharp leg pains. Atherosclerosis can cause problems with blood flow to muscles in the legs, resulting in sharp pains referred to as claudication that occur while walking. Disorders of the veins in the legs, including varicose veins and blood clots can also cause sharp leg pains.
  
  

Muscle Disorders

• Disorders of the muscles, tendons and ligaments in the legs may be a cause of sharp leg pain, according to the National Library of Medicine. Inflammation of a tendon, which is referred to as tendinitis, can cause sharp leg pains, especially around the knees. A strained or torn muscle can also be a cause of sharp leg pain. Sometimes the pain is not felt until several hours after the muscle is damaged.
  
  

Nerve Disorders

• Disorders of the nerves in the legs can be a cause of sharp leg pain, according to the Mayo Clinic. Peripheral neuropathy is a chronic condition that causes damage to the nerves in the toes, feet and legs and can result in sharp pains. Sharp leg pains can also be a result of sciatica, which is an inflammation of the sciatic nerve that goes from the lower back to the toes.
  
  

Physical Activity

• Overuse or intense physical activity can be a cause of sharp leg pain, according to the National Library of Medicine. Shin splints are a common type of sharp pain in the front of the lower legs, and often occur after exercise on an incline or running. Prolonged or strenuous exercise can cause the leg's muscles to become fatigued or inflamed, which is another possible cause of sharp leg pains.