Leg Pain

Picture of the muscle and nerve anatomy of the leg

• While leg pain is a common occurrence after an injury, pain may also occur because of medical conditions or nontraumatic reasons.
• Pain in the legs may be due to injury or inflammation of any of the structures that are found in the leg, including bones, joints, leg muscles, tendons, ligaments, blood vessels, nerves, and skin. Inflammation of tissue is usually the cause of pain.
• Pain can also radiate from other parts of the body and manifest in the leg. Low back ailments may cause pain and numbness in the leg. Abdominal aorta and iliac artery aneurysms can also present with leg pain. A blood clot in the large veins and arteries located in the abdomen, pelvis, or legs is another cause of leg symptoms.
• Systemic diseases like diabetes can cause nerve or artery damage that can result in chronic foot pain and leg pain.

The structure of the leg begins with the skeleton. The large bones of the leg are the femur (thighbone) and the tibia and fibula of the shin. The patella (kneecap) is located in front of the knee joint where the femur and tibia meet. Smaller bones are in the feet and toes. Major joints of the leg include the hip, knee, and ankle, but the small joints in the feet and toes are important since they help support the body and cushion the force that is generated by walking and running.

Thick bands of tissue called ligaments stabilize the joints. The ends of a bone that make up part of a joint are covered with cartilage to help them glide through their range of motion and decrease the friction of bone rubbing on bone.

Muscles attach to bone and have tendons that stretch across a joint. When a muscle contracts, the joint moves. Major muscle groups that affect leg movement include the buttocks, the quadriceps (in the front of the thigh), the hamstrings (in the back of the thigh), and the gastrocnemius (in the back of the calf). There are other smaller muscles, including those in the foot, that help stabilize the multiple joints in the feet.

There are two sets of blood vessels in the leg. The arterial system delivers blood, rich with oxygen, from the heart. The aorta leaves the heart and descends into the abdomen, divides into the iliac arteries, and further splits into the femoral arteries at the level of the groin. The femoral artery runs along the back of the femur in the thigh, where at the back of the knee (the popliteal fossa) it begins branching into smaller and smaller arteries to supply the lower leg, feet, and toes with blood.

The venous system drains blood from the leg and returns it to the heart, allowing tissue like muscle to get rid of carbon dioxide and other waste products of metabolism. There are two sets of veins in the leg, the superficial and deep venous systems. The superficial system runs along the skin while the deep system is located deep within the muscles and along the bones. Blood drains from the superficial system to the deep system through connecting veins called perforators that prevent blood clots that occur in the superficial veins from entering the deep vein system and embolizing or traveling to the heart and lungs. The superficial and deep systems come together in the groin to form the femoral vein.

Nerves from the spinal cord supply information to the leg, transmitting signals from the brain that allow purposeful movement. They also return information or sensations to the brain. These include the sensations of pain, light touch, pressure, vibration, temperature, and position. As well, nerve impulses can flow from the legs to the spinal cord and back without going up into the brain. These nerve loops allow the health care professional to test deep tendon reflexes (when the knee or ankle are tapped with a hammer) to assess spinal cord function.

Illness and injury can affect any of these structures, causing inflammation, discomfort, and pain. More than one mechanism may occur at the same time to cause leg pain. Some examples include the following:

• People with poorly controlled diabetes may develop diabetic neuropathy, in which the nerves to the legs and feet malfunction. Symptoms may include pain and loss of sensation in the feet as well as a pins-and-needles or tingling sensation. Diabetes is also one of the risk factors for peripheral vascular disease, which may cause the narrowing of arteries in the legs, decreasing blood flow to muscles. Lack of blood supply may cause exercise-induced (exertional) pain or claudication, in which muscles start to ache with activity because not enough oxygen-rich blood can be delivered. Intermittent claudication is the term used to refer to pain in the legs that occurs while walking due to peripheral artery disease (peripheral vascular disease). This pain usually gets better with rest. As arteries narrow over time, decreased activity will bring on increased pain.
• An injured muscle will cause pain because of inflammation and swelling, but it may also affect the balance of muscles surrounding a joint. If this imbalance persists, the joint may start to hurt because of chronic stress placed upon it.
• People with back problems due to arthritis or a ruptured disc may develop sciatica, or pain from the sciatic nerve that radiates down the leg. Sciatica may also be associated with numbness and/or tingling in the leg.

Trauma

Trauma is the most obvious cause of leg pain. Falls, near falls, direct blows, and twisting injuries can damage bones, muscles, and joints of the leg or a combination of all three. Back pain, due to injury, can inflame the sciatic nerve and cause sciatica. This pain that radiates down the leg that follows the path of one of the many nerve roots that leave the spinal cord and make up the sciatic nerve. Sciatic pain usually begins in the back and radiates to the buttock and into the front or back of the thigh and potentially down the leg to the foot, depending upon which nerve root exiting the back is inflamed.

Overuse injuries may cause pain; these injuries are multiple minor traumatic injuries to muscles, tendons, and joints that occur over a longer time span.

• Fractures: When referring to a bone, the terms fracture, broken, and cracked all mean the same thing -- the integrity of the bone has been compromised. The most common symptom is pain that occurs because the nerve endings located in the fibrous tissue lining of the bone, called the periosteum (peri=surrounding +osteum=bone), have become damaged and inflamed. As well, the muscles surrounding the bone go into spasm and intensify the pain.
• Stress fractures: Some fractures occur because of repetitive small traumas to a specific area of the body. March fractures describe a fracture of one or more of the metatarsal bones in the foot (the long bones at the base of the toes) that are caused by overuse that fatigues the bone. The name comes from the fact that they are found in soldiers who are forced to march long distances as part of their training.
• Shin splints are an overuse injury to the tibia or shinbone. This condition is also known as tibial stress syndrome. Running, jumping, and dancing are the most common causes. Microscopic fractures occur in the tibia, causing pain and swelling. If the person continues to exercise and disregards the pain, a shin splint can progress to break the bone completely.
• Sprains and strains: A ligament injury is a sprain and occurs when the ligament fibers are stretched, or partially or completely torn. People can stretch or tear muscles and tendons, causing a strain. Both sprains and strains result in swelling and inflammation that causes pain. Sometimes a sprain or strain can occur at the location where the structures attach to bone, and a small fleck of bone pulls off at the insertion of the muscle, tendon, or ligament. This is an avulsion fracture that health care providers often treat in the same manner as a strain.
• Bursitis: There are small, fluid-filled sacs that cover large bony prominences and allow tendons to slide across the bone. Bursitis, or inflammation of the bursa sac, may occur with overuse or injury, like a direct blow. Two bursas in the leg that may commonly become inflamed are the trochanteric bursa, which covers the bony prominence of the femur on the outside of the hip, and the ischial bursa, which covers part of the pelvic bone where we sit.
• Bleeding: Injuries can also cause bleeding into tissues and joints. Since it isn't possible to compress blood, the swelling causes a significant amount of pain as the pressure increases. Blood is also very irritating to the surrounding tissues when it leaves blood vessels and causes pain by its presence alone.
• Compartment syndrome is a medical emergency. It describes the situation in which excessive swelling occurs within the sections or compartments of the leg that contain muscles. This may cause increased pressure within the compartment that is greater than the blood pressure generated when the heart beats. Blood supply cuts off within the compartment, causing pain, numbness, and an inability to move the foot or ankle. This is a true surgical emergency, requiring the opening of the compartments and relieving the pressure within to restore blood supply and prevent permanent disability. One of the hallmarks of the diagnosis is the finding of pain out of proportion to physical findings. Health care professionals confirm the diagnosis by measuring pressures within the compartment.

There are numerous causes of nontraumatic leg pain, and there is no single way of classifying all of these causes. Health care providers often develop their own individual approach to help decide upon a diagnosis. Sometimes it can help to classify the potential causes based upon the part of the leg that hurts, whether the pain is in one leg or both, whether related to activity or rest, and whether underlying medical conditions exist that can precipitate leg pain.

Pain in only one leg would tend to be due to local problems and not necessarily due to a systemic (involving the entire body) illness. The presumption would be that such an illness would affect both legs. This is not necessarily always true. For example, gout (a defect in the body's ability to process uric acid) often attacks only one joint during an acute flare.

• Peripheral artery disease (PAD): Pain in one leg, or both, may be due to peripheral artery disease, a decrease in arterial blood supply to the leg due to narrowing of arteries. Often the pain comes on with activity since walking requires more oxygen for the muscles. If the arteries are narrow and can't supply that need, the muscles begin to ache. Blood vessels can narrow at any level, from the aorta (the large blood vessel that leaves the heart) to any of the branch arteries. Depending upon the level of narrowing and the particular muscles involved, the areas of perceived pain may be different.
  
  Claudication is the term for leg pain from peripheral artery disease that occurs with walking. Since peripheral artery disease often affects more than one blood vessel, both legs may be affected, although the pain may be of different severity in each leg. The blood supply may decrease to the point that pain occurs at rest, even without exercise. Poor blood supply to the legs may also compromise the integrity of the skin and may allow infection to occur. As well, poor blood supply makes it difficult for wounds like lacerations or abrasions to heal.
• Blood clot: An arterial (in an artery) blood clot of a leg artery can completely obstruct blood supply, preventing tissues from getting oxygen-rich blood from the heart. This can cause the acute onset of pain. Aside from pain, the leg may become cool and pale. While there are many potential sources of a blood clot, one common place to look is the heart. If the cardiac arrhythmia known as atrial fibrillation is present, there is the potential that small clots can form on the lining of the heart and break off to travel through the arteries, obstructing blood flow at any points distant from the heart. Aside from the leg, the obstruction may occur in one of the blood vessels leading to the brain leading to stroke, or one of the arteries to the intestine, causing bowel ischemia. A blood clot can also occur acutely in a partially narrowed artery. Just like arteries in the heart that can narrow over time because of cholesterol or plaque buildup, the same situation may occur in the legs. If the plaque becomes irritated or ruptures, the body can form a clot at the site, occluding the artery and immediately stopping the blood supply to the part of the leg beyond the clot.
  
  A venous (in a vein) blood clot can also cause pain. Veins return blood from the legs to the heart. There are two systems of veins in the leg: superficial and deep. If a blood clot occurs in a deep vein (deep venous thrombosis, DVT), it causes a "damming" effect, trapping blood behind the blockage. This causes redness, swelling, warmth, and pain in the affected area. Calf pain and swelling are common symptoms.
  
  Superficial veins can also clot and cause pain, but the risk of complications from a deep vein thrombosis (breaking off and embolizing to the lungs [pulmonary embolism]) is not often present. A superficial thrombosis (blood clot) may not be able to travel to the lung because the valves in the perforator veins that connect the superficial vein system to the deep system act as a sieve. However, if the clot develops near the groin where the two systems come together, the clot can embolize into the lungs. Superficial veins can also chronically dilate and swell and form varicose veins. Varicose veins may cause pain from this swelling and inflammation.
• Low back pain: Low back pain from sciatica (inflammation of the sciatic nerve) may radiate into the buttocks and down the leg. The distribution of pain depends upon which nerve root is involved; therefore one may feel the pain in the foot, shin, or thigh. A variety of changes in the back from arthritis, a herniated disc, muscle spasm, or injury may cause sciatica. The common outcome is narrowing of the space where the nerve exits the spinal canal, and there is impingement upon the nerve and inflammation. Less commonly, tumors and infection can cause nerve root and spinal cord inflammation and resultant leg pain.
  
  While a herniated disc or arthritis can pinch a nerve root that exits the back at one or more levels, spinal stenosis may affect long segments of the spinal cord because the spinal canal itself becomes narrow, not leaving enough room for the spinal cord itself. Spinal stenosis may result in pain, numbness, and weakness.
  
  Cauda equina syndrome describes a neurosurgical emergency in which back pain may be associated with weakness, numbness around the perineal area (rectum, scrotum, vagina), inability to urinate, and loss of bowel control. The spinal cord ends in a mass of nerve roots that appear like a horse's tail (cauda equina in Latin) that can become inflamed if there is damage to the area due to trauma or any other type of compression, including tumors.
• Neuropathy: Pain may occur from peripheral nerve inflammation not associated with the spinal cord. These conditions are peripheral neuropathies. This can occur from direct nerve irritation or from a medical illness. Examples of this type of isolated nerve injury include foot and toe pain from a Morton's neuroma, most frequently a thickening and inflammation of a nerve that supplies the third and fourth toes, or meralgia paresthetica that causes pain in the anterior thigh resulting from entrapment of a nerve that leaves the pelvis. This neuropathy appears in pregnancy when the pressure of the uterus may cause the nerve to become inflamed. These types of pain tend to involve part of one leg only. Diabetes is a common cause of peripheral neuropathy that affects both lower extremities. Alcohol abuse is another common cause of peripheral neuropathy.
• Illness: Chronic illnesses like diabetes, alcoholism, cancer, and vitamin deficiencies (for example, B12 deficiency causing pernicious anemia) may also result in nerve pain that often affects both legs. There are some illnesses that cause leg weakness that may be associated with complaints of leg pain, including Guillain-Barré syndrome, transverse myelitis, and multiple sclerosis.
• Skin: Skin inflammation may also cause significant pain, especially if there are underlying illnesses like diabetes or peripheral artery disease that prevent adequate healing. The inflammation may be due to infection often caused by Streptococcus or Staphylococcus bacteria. Skin stretched due to edema or fluid accumulation in the tissues underneath the skin can cause significant pain especially when the legs are not elevated.
• Shingles can cause significant pain due to inflammation of the spinal cord nerve in the body. It is a reactivation of the chickenpox virus that resides in a dormant state in the nervous system following infection of the patient years previously. Since the nerve is inflamed, there can be significant amounts of pain. As well, a rash can occur along the course of the nerve. The rash may appear a few days after the pain begins and may resolve before the rash goes away. Sometimes the pain persists chronically even after the rash resolves (postherpetic neuralgia).

• Joint pain: Joint pain may occur because of a local injury but may also be due to medical conditions that can cause inflammation and swelling. Joint pain associated with swelling is called arthritis (arth=joint+ it is=inflammation) while pain without swelling is called arthralgia (arthr=joint + algia= pain). Some examples include the following:
  • Patients with progressive osteoarthritis may have days in which affected joints may hurt.
  • Similarly, patients with rheumatoid arthritis may have episodes of joint inflammation when their disease flares.
  • Exacerbations of gout can cause joints to become inflamed if uric acid crystals start to deposit within the joint. It is often the joints that are under significant workload that are affected. The joints in the great toe are commonly involved, but the ankle, knee, wrist, and fingers are also common sites of uric acid crystal deposition. Gout is due to an inborn error of metabolism and the inability of the body to regulate uric acid levels in the blood adequately.
  • Pseudogout can also cause joint inflammation. Instead of uric acid, calcium pyrophosphate crystals deposited in joints are the cause of this condition. Pseudogout often affects the knee, and the diagnosis is sometimes made when calcification of the cartilage is seen on plain X-rays of the knee joint (chondrocalcinosis). Pseudogout is also an inborn error of metabolism.
  • Systemic illnesses (there are too many to discuss in this article) may also cause joint inflammation. Some common conditions that may cause joint pain include inflammatory bowel disease (SLE), psoriasis, hepatitis, inflammatory bowel disease, and Lyme disease.
  • Joints may become inflamed as part of the body's generalized reaction to an infection. Infections may cause synovitis, or inflammation of the synovium (the lining tissue of a joint). Most often it is due to a virus, but in children, there is always a concern that a bacterial infection may be the cause. Other risk factors for joint infection include intravenous drug abuse and sexually transmitted diseases (STDs).
  • People who take anticoagulation medications like warfarin (Coumadin), enoxaparin (Lovenox), prasugrel (Effient), enoxaparin (Lovenox), dabigatran (Pradaxa), rivaroxaban (Xarelto), or apixaban (Eliquis) to thin their blood may spontaneously bleed into a joint or muscle, causing pain.
• Muscle pain: Muscle pain or myalgia (myo=muscle +algia=pain) is a common complaint and may be due to overuse (mild trauma) or associated with the generalized aches and pain of an infection. Muscles may also become inflamed for a variety of reasons (myositis: myo= muscle + itis=inflammation), including side effects of some cholesterol medications.
• Muscle cramps: Muscles may cramp, causing significant pain. This may be due to a lack of stretching, dehydration, or an imbalance of electrolytes in the bloodstream. The body needs to have the right amount of calcium, sodium, and potassium for muscles to function well. Calf and foot muscles are particularly prone to muscle cramps, especially at night.
• Muscles will also go into spasm to help protect an injured site. For example, when a hipbone is broken, the muscles that move the hip will go into spasm to help minimize the movement of the injury.
• Heat cramps occur as part of the spectrum of heat-related illnesses due to dehydration and electrolyte imbalances. They may occur immediately after exercising or working in a hot environment or their onset may appear a few hours later. Often it is the large muscles of the legs that are involved because of the amount of work they have to do.
• Muscle injuries: The muscles in the leg tend to be in balance with each other to promote joint stability and act as shock absorbers for the forces generated by walking and running. The quadriceps muscles on the front of the thigh extend or straighten the knee, and the hamstring muscles in the back of the thigh responsible for flexing or bending the knee balance them. If this balance is lost, the muscle fibers may become overstretched and tear. This is a strain.
• Hamstring injury: The hamstring (posterior thigh muscle group) makes up a group of individual muscles known as the semitendinosus, the semimembranosus, and the biceps femoris. While one can feel the tendons at the back of the knee, the muscle originates and is anchored in the pelvis bone. When the muscle contracts, the knee bends and the leg is able to generate power to push the foot away from the ground so that the body can walk. Walking also requires the quadriceps muscles to extend the knee fully so that the heel of the foot can strike the ground and begin the footstep.
  
  If the hamstring muscle tendon fibers are not flexible or if there is too much stretch placed on the structure, these fibers may be damaged if the knee extends too much or too quickly. One may stretch or even tear muscle or tendon fibers, causing pain and swelling. To protect itself, the muscle may go into spasm, which may cause even more pain.
• Skin abnormalities: Skin abnormalities may cause pain. Lacerations and skin tears, ranging from trauma to ulcers caused by poor blood flow, are among the causes of pain from skin conditions. The skin has numerous nerve fibers that can sense pain, and anything that damages the skin can cause pain. Skin infections may be painful, again because of inflammation and swelling.
• Leg pain in children: Leg pain in children is a special situation. While most leg pain in children is not serious, there are times when the pain has a significant cause. These may include joint infection, causing hip pain, trauma causing damage to growth plates, and pain due to systemic illnesses like Henoch-Schönlein purpura, juvenile rheumatoid arthritis, or rheumatic fever.
  • "Growing pains" are most likely due to muscle overuse, although they may be associated with mild stretching as the muscles grow along with the bone.
  • A health care provider should evaluate children with leg pain who limp or who will not bear weight on the leg. Often children will complain of knee pain, but the actual cause is in the hip joint, whether it is an injury, infection, or inflammation.
  • Some fractures in children may be difficult to diagnose because immature bones may not have completely calcified due to the presence of growth plates. Fractures may not be evident on plain X-rays, and clinical judgment may be needed to decide whether a broken bone is present.
  • Legg-Calve-Perthes disease describes avascular necrosis or loss of blood supply to the femoral head (the ball of the hip joint). The cause is unknown, but it most commonly affects children, especially boys, from ages 4-8 and causes hip pain and a limp. Treatment involves resting the hip joint to prevent long-term arthritis, and an orthopedic specialist usually supervises care.
  • Osgood-Schlatter syndrome describes an inflammation of the apophysis of the tibia, the bony protuberance where the patellar tendon attaches to the bone below the knee. This condition occurs because of excess strain on the growth plate of the upper tibia and is often due to excess jumping or running. It can cause a tender, swollen area just below the knee. The condition heals with ice and rest.
• Diabetes: Diabetes may cause leg pain in a variety of ways. If one doesn't control their blood sugar levels over a period of many years, nerves and blood vessels deteriorate and lose their function. Often the damage occurs in the feet and progresses up the leg. With the loss of sensation, skin infections and foot injuries may occur without the affected person feeling much discomfort. Alternatively, the nerves may be so inflamed that the patient feels intractable pain. Diabetes also causes blood vessels to narrow and cause symptoms of PAD (peripheral artery disease) or claudication.
  
  People with diabetes are also more prone to infection because of an impaired immune system. Along with poor blood supply to the legs, people with diabetes may have a decreased ability to heal skin damage and an increased risk of foot and leg infections.
• Phantom leg pain: People who have had a limb amputation may feel as if the limb is still there and develop pain. This is due to a brain response to the amputation and an attempt to rewire the body's nervous system to account for the missing part. The pain begins shortly after the operation and may be intermittent or continuous. Often people perceive the pain in the furthest part of the missing limb, so in a leg, it would be the foot or toes. Those affected describe the pain in a variety of ways, from shooting and stabbing to a pressure or burning sensation.

Depending upon the cause and the individual situation, symptoms of leg pain may have a wide range of presentation. People describe the pain in a variety of ways, including sharp, dull, heavy, aching, or burning. It may be constant or intermittent or made better or worse with activity or rest. There may be other associated symptoms, depending upon the cause.

People can often feel or palpate pain from muscles and joints, meaning that touching the area reproduces the pain. This may be difficult if the pain originates in one of the muscles deep in the buttock. An example is piriformis syndrome, where the piriformis muscle, one of the muscles that helps rotate the hip and located beneath the gluteus maximus, becomes inflamed and irritates the sciatic nerve that runs beneath it. Physical exam may not be able to confirm the diagnosis suggested by a history of increasing hip pain and sciatica with a normal back exam.

Pain also may radiate from its source to another location, sometimes confusing the patient and the care provider. For example, hip problems may initially present with knee pain; this is especially true in children and it is important to look at the hip whenever a child limps or complains of knee discomfort. With some injuries and arthritic conditions, the pain gradually resolves as the muscle or joint warms up during activity, but other times, the pain is worse with use.

Patients who suffer from claudication develop pain with exercise, but as the blood vessels narrow over time, the amount of activity required to bring on the pain decreases. Also, this type of pain tends to resolve with rest. As the disease progresses, at some point, the patient may complain of pain at rest, not requiring exercise or activity to bring it on.

Those who have a blood clot causing ischemia (decreased oxygen supply to the tissues) tend to have an acute onset of pain that is intense and involves the whole extremity below the area of the arterial blockage. There may be associated numbness or paralysis. Sometimes the body is able to dissolve the clot on its own and as the blood supply is restored, the pain resolves. Most often, though, this true emergency requires treatment to dissolve or remove the clot to prevent loss of the leg.

People with neuropathy tend to describe their pain as a burning sensation, while those who have sciatica describe intense sharp pain. Sciatica may also cause changes in sensation along the path of the inflamed nerve root.

Nighttime symptoms of pain and leg cramps may be associated with restless legs syndrome, a sleep disorder.

People often decide to seek care after an injury based upon their ability to stand, bear weight, and walk. This is often reasonable; however, if there is concern that a bone is broken or there is significant swelling to a joint, one should seek medical care in an urgent manner. A swollen joint is never normal. One important reminder: Just because the leg can move does not mean that it is not injured.

In most other situations, leg pain has a gradual onset and patients seek medical attention when the pain begins to interfere with their daily lives. Often, leg pain is a part of a larger collection of symptoms and is not evaluated independently.

However, when leg pain begins suddenly, it should be a cause for concern and one should seek medical care urgently. This is especially the case if the leg is warm and swollen and deep venous thrombosis is of concern, or if the leg is pale and cool and an arterial clot is a consideration.

If back and leg pain occurs with episodes of increased muscle weakness, falling, or changes in bowel or bladder function, this may signal an emergency involving the spinal cord called cauda equina. Access medical care immediately.

Children who develop leg pain and begin to limp or who develop a fever and a limp should be seen immediately for evaluation.

The evaluation of leg pain always begins with the health care provider interviewing the patient and performing a physical examination to help determine the potential cause of the leg pain. The decision about diagnostic testing, including blood tests and X-rays, depends upon the provider's concern as to what the cause of the leg pain might be. Sometimes testing and X-rays are not required.

Blood Tests

Blood tests including a white blood cell count, an erythrocyte sedimentation rate (ESR), and a C-reactive protein (CRP) measurement may help assess for an infection or inflammation. These nonspecific tests may give further direction to the health care provider. Please note that the white blood cell count may be elevated with an infection unless the patient has a compromised immune system, at which point it may be falsely normal. As with all tests, if the ESR and CRP are elevated, health care professionals need to interpret the results in light of the specific illness that is being considered.

If gout is a consideration, health care providers may perform a blood test to measure uric acid; however, in an acute attack, the uric acid level may be high, low, or normal. The result is helpful if the level is high and may confirm a gout flare if supported by the history and physical examination.

Your doctor may consider other blood tests depending upon the underlying medical illnesses being considered.

Imaging

• X-rays: If there is concern that a fracture or broken bone is present, medical professionals may perform plain X-rays. As well, health care providers may take X-rays as a screening to look for fluid or calcifications in a joint.
• Ultrasound: An ultrasound may be helpful in making the diagnosis of deep vein thrombosis (DVT). Doctors make a clinical diagnosis of superficial vein thrombosis based upon the physical examination, and no imaging may be required. Ultrasound may also be helpful to diagnose joint inflammation and swelling.
• Ankle-brachial index (ABI): Health care providers may assess arterial blood flow in the legs by an ankle-brachial index, in which blood flow is evaluated at rest and with exercise. This test involves comparing the blood pressure in the arms to the blood pressure in the legs.
• Arteriogram: If a physician needs further information about the arteries, an arteriogram may be performed to look directly at the arterial supply to the legs. This is accomplished by injecting contrast dye directly into the arteries and watching it flow through the arteries in the legs via X-rays. Arteriography may also be performed using CT or MRI studies (see below).
• CT scan: Computerized tomography (CT) may be used in a variety of situations. CT angiography may be able to take the place of arteriography in some situations to examine blood vessels. CT may also be used to evaluate bone and joint anatomy, looking for hidden fractures.
• MRI: Magnetic resonance imaging (MRI) may be used to examine the back for the causes of sciatica to evaluate bones, joints, and soft tissues such as muscles, tendons, and ligaments. MRI angiography may also be considered in place of formal angiography to evaluate blood vessels in the body. MRI is also of use in looking for hidden or occult fractures.
• Nerve conduction studies: Nerve conduction studies may be considered to evaluate nerve function and measure the ability of specific nerves to carry electrical impulses. This is helpful in deciding whether nerve pain is due to a central cause from the brain or spinal cord or a peripheral nerve injury. (For example, inflammation of the ulnar nerve from hitting the funny bone can cause the ring and little fingers to go numb and is not caused by a stroke.)
• Joint aspiration: If there is concern about infection or inflammation within a joint, a needle may be put into the joint to pull out or aspirate fluid for analysis. Often this fluid is sent to a laboratory to analyze the white blood cell count within the fluid (an elevated white blood cell count may signal inflammation), a gram stain and culture looking for bacterial infection, or crystal analysis looking for uric acid or calcium pyrophosphate crystals to make the diagnosis of gout or pseudogout, respectively.
• Compartment pressures: If compartment syndrome is suspected, compartment pressures may be obtained from the muscular compartments of the leg and/or thigh. Elevated compartment pressures may indicate the presence of compartment syndrome. This is an emergency situation that may require surgical release (incision) of the affected compartment(s) to relieve the elevated pressure and restore blood flow and nerve function.

The treatment of leg pain depends upon the diagnosis. Once the reason for the pain is established, treatment is focused on both pain control and controlling the underlying problem to prevent or lessen future occurrences.

Self-care at home depends upon the reason for the leg pain.

• For sprains and strains, RICE is the initial recommendation: rest, ice, compression, and elevation. Acetaminophen (Tylenol) and ibuprofen (Advil) may be used for pain control. Over-the-counter medicines are usually safe to take but may interact with other prescription medications. Health care providers or pharmacists are usually available for questions and advice.
• Hamstring and calf injuries generally heal with the body's production of collagen fibers to build scar tissue in the area of muscle damage. Depending upon the severity of damage, it may take days to weeks to completely heal. The treatment of a strain is RICE (rest, ice, compression, and elevation). Once the initial phase of recovery begins, it is important that the muscle regain its length. Often, stretching exercises and massage are used to help restore the hamstring muscles to their full length to allow full range of motion of the knee and leg. The decision as to when to start these exercises or to use other types of physical therapy is individualized for every patient and is often made by the health care provider.
  
  Crutches may be used in the first few days after injury to rest the leg. Elastic bandages (Ace wraps) may be applied to the thigh, beginning at the knee and moving upward to the hip joint to provide compression.
  
  Ibuprofen may be suggested as an anti-inflammatory medication and for pain control. As with any over-the-counter medication, it is important to check with a pharmacist or health care provider to make certain that it is safe to take ibuprofen in each specific case.
• People with sciatic pain should continue with activity as tolerated. Bed rest is no longer recommended. People with sciatic pain tend to return to normal activity more quickly if the amount of bed rest is minimized. Alternating ice and heat may be helpful; acetaminophen and ibuprofen may also be used. Chiropractic or physical therapy treatments may be of help. If the pain is associated with a change in bowel or bladder function, this may indicate cauda equina syndrome, in which the spinal cord is at risk of permanent damage, and emergency care should be accessed immediately.
• For patients with chronic medical conditions, prevention is often the best treatment. The pain of neuropathy in people with diabetes is very hard to control; a lifetime of blood-sugar control minimizes the risk of this and other complications in later life.
• Similarly, lifetime control of high blood pressure, high cholesterol, and diabetes along with smoking avoidance will minimize the risk of peripheral vascular disease, heart attack, and stroke.
• Most conditions that cause leg pain arise slowly, and home care should be individualized for each patient. One's health care provider is an important resource for diagnosis, prevention, and treatment.
• If acute pain with leg swelling or loss of feeling associated with a cold leg occurs, medical care should be accessed immediately.

Therapy for leg pain depends upon the cause. Once the diagnosis is confirmed, care will be tailored to the specific needs of the patient.

Depending upon the cause of leg pain, the need for further care may be minimal if it is due to an injury, or it may be lifelong if it is associated with a chronic condition such as diabetes or arterial disease.

There is a school of thought that says that all injuries are preventable, but in the real world, accidents happen and injuries are the result. Some acute situations are potentially avoidable:

• When traveling long distances by car, train, or by air, get up and walk every couple of hours to decrease the risk of deep venous thrombosis (DVT).
• For those prone to falls, using a cane or walker may be helpful. As well, footwear with good grips should be encouraged. Falls can occur when the walking surface changes, for example, walking from a carpeted room to one with bare floors or slipping on throw rugs. Home health-safety assessments to minimize these kinds of fall risks may be available through one's health care provider or the county health department.
• Maintaining an ideal weight will decrease the lifetime stress on bones and joints and decrease the potential for arthritis and obesity-related illnesses.
• A regular exercise program and a healthy balanced diet, including adequate calcium and vitamin D intake, will maintain strong bones and joint flexibility. Screening for osteoporosis is recommended for women over age 65 and younger women at higher risk for the condition.
• For those with long-term medical conditions, maintaining good control of the disease is a lifelong commitment and may minimize the risk of developing complications. This is especially true for diabetes, high blood pressure, and high cholesterol levels. Avoid smoking since it is a major risk factor for blood vessel disease.

Advances in the management of chronic pain are occurring routinely, and those with chronic leg pain may be beneficiaries of that research. For those patients who have pain due to chronic medical conditions, there is potential for relief. It is important to talk with your care provider so that he or she understands your specific situation in order to help meet your needs.