Pain in the Leg Below the Knee: Possible Causes

Pain below the knee can come from bone, muscles, blood vessels, or nerves. Below, the possible causes of such pain and the reason for an examination are discussed.

Where the area below the knee is located and what it consists of

The lower leg is the part of the lower limb from the knee to the heel. Its foundation is provided by two bones: the tibia and the fibula. At the top they articulate, along their entire length they are connected by a membrane, and at the bottom they end in the medial and lateral malleolus, where they are connected by ligaments. Muscles of three groups attach to the bones: the anterior muscles extend the foot and toes, the lateral muscles flex the foot and abduct it outward, and the posterior muscles flex the toes and foot. The gastrocnemius and soleus muscles merge into the Achilles tendon and attach to the calcaneus. In addition to bones and muscles, the leg contains blood vessels and connective tissue, so the source of pain can be in any structure.

Pain in the front: bone and periosteum of the lower leg

A classic in runners is pain and tenderness along the anterior surface of the lower leg, along the tibia. This is the so-called shin splints: a type of lower leg pain that is usually related to loading. The cause is excessive strain in the leg. The risk is higher if a person started training after a break, runs or jumps on hard surfaces, and running technique leaves much to be desired. Usually this condition subsides within a few weeks.

Injuries after a fall or accident can lead to fractures, including of the tibia. In shin splints, the diagnosis is usually made by examination and asking about symptoms; if there is no improvement, physical therapy may be needed.

Pain on the side, on the outer aspect

On the outside run the fibula and the lateral malleolus, and nearby lie the lateral muscles, which flex the foot and abduct it outward. Among the conditions considered for leg pain, impaired function of the common peroneal nerve is also mentioned.

Pain on exertion

For shin splints, pain on exertion, for example when running, has been described. Among the causes of leg pain, night cramps and intermittent claudication are mentioned.

Vascular and nervous causes of pain

Veins give rise to varicose veins and deep vein thrombosis; thrombophlebitis is also mentioned among the conditions. There can be leg edema, lymphedema, venous insufficiency, and ischemic ulcers. In older people, osteoarthritis of the knee joint can cause pain and limited movement, although this is already about the joint rather than the lower leg. Among nervous causes, peripheral neuropathy is mentioned. Blood vessels are assessed, among other ways, via the ankle-brachial index, and bones via X-ray of the lower leg, that is, the tibia and fibula.

When to see a doctor

If pain along the anterior surface of the lower leg does not ease but increases, a doctor is needed. Further, physical therapy and examinations may be needed, for example X-ray or the ankle-brachial index. Reasons for a scheduled visit would be the following situations:

• the pain intensifies or does not go away after home measures;
• severe pain;
• injury to the lower leg.

Lower leg pain by itself is not a reason to call an ambulance; 103/112 — for a life-threatening condition, for example after a serious accident or severe injury.

The material is for reference and does not replace a doctor's consultation.

This content is for reference and does not replace a doctor's consultation. Medical disclaimer