Leg pain affects roughly 1 in 3 American adults in any given three-month period, making it one of the most common pain complaints after back pain. The causes range from a simple muscle cramp to a blood clot that needs emergency treatment, so the type of pain, where exactly you feel it, and what makes it better or worse all matter. Here’s a breakdown of the most likely reasons your legs hurt and what each one actually feels like.
Muscle Strains and Cramps
The most common and least worrying cause of leg pain is a strained or overworked muscle. This happens when you push harder than usual during exercise, skip warming up, or suddenly increase your activity level. The pain is usually localized, feels sore or tight, and gets better within a few days of rest. You can often pinpoint the moment it started.
Nighttime leg cramps are a related but distinct problem. Your calf or foot suddenly seizes up, often waking you from sleep. Dehydration, prolonged standing, and low levels of minerals like potassium and magnesium are frequently blamed, though the exact mechanism isn’t fully understood. These cramps are more common in older adults and during pregnancy. Stretching the affected muscle and staying well hydrated are the most reliable ways to reduce their frequency.
Poor Blood Flow From Artery Disease
Peripheral artery disease (PAD) affects about 6.5 million Americans age 40 and older. It develops when fatty deposits narrow the arteries supplying your legs, reducing blood flow. The hallmark symptom is a cramping or aching pain in your calves, thighs, or hips that starts when you walk and stops when you rest. This pattern is called claudication, and it’s one of the most reliable clues that your leg pain is vascular.
PAD pain tends to be predictable. You might notice it consistently after walking a certain distance, like two blocks or halfway up a flight of stairs. Over time, the distance you can walk without pain may shrink. Supervised exercise programs can actually improve walking distance significantly. Smoking, diabetes, high blood pressure, and high cholesterol all raise your risk, so if your leg pain follows this pattern, it’s worth getting checked.
Blood Clots in the Deep Veins
Deep vein thrombosis (DVT) is a blood clot that forms in the deep veins of your leg, usually the calf or thigh. It causes swelling, warmth, and a deep aching pain that doesn’t come and go with activity the way artery disease does. The affected leg may look red or discolored, and the calf can swell noticeably. In clinical assessments, a calf that measures at least 3 cm larger than the other side is considered a significant warning sign.
DVT is more likely after long periods of immobility (a long flight, bed rest after surgery, or wearing a cast), in people with active cancer, and in those with a history of previous clots. The danger isn’t just the leg pain itself. A clot can break loose and travel to the lungs, causing a pulmonary embolism. If you have sudden leg swelling with pain, especially on one side only, that combination warrants urgent medical evaluation.
Nerve Compression and Sciatica
When a nerve in your lower back gets compressed, typically by a herniated disc or bone spur, the pain often radiates down into your leg. This is called radiculopathy, and when it involves the sciatic nerve, most people know it as sciatica. The pain can feel sharp, burning, or electric, and it tends to follow a specific path depending on which nerve root is pinched.
A compressed nerve at the L4 level typically sends pain and numbness to the inner ankle and inner foot, and you may have trouble straightening your knee with full strength. Compression at L5 affects the top of the foot and can make it hard to pull your foot upward. At the S1 level, pain and numbness travel to the outer ankle and outer foot, and rising onto your toes may feel weak. These patterns are useful because they help distinguish nerve pain from muscle or vascular problems. Sciatica pain often worsens with sitting, coughing, or sneezing, which increases pressure on the compressed nerve.
Diabetic Nerve Damage
Persistently high blood sugar damages the small blood vessels that supply oxygen to your nerves, and over time, the nerves themselves start to malfunction. This condition, diabetic neuropathy, most often affects the feet and lower legs first. The pain is distinctive: burning, tingling, or sharp cramps, frequently worse at night. Some people become so sensitive to touch that even the weight of a bedsheet causes pain.
Unlike sciatica, which follows a clear line down one leg, diabetic neuropathy usually affects both legs symmetrically and starts at the toes before creeping upward. It develops gradually over months or years, so many people initially dismiss the early tingling. Keeping blood sugar well controlled is the most effective way to slow or prevent further nerve damage.
Chronic Venous Insufficiency
Your leg veins have one-way valves that push blood back up toward your heart. When those valves weaken, blood pools in the lower legs, a condition called chronic venous insufficiency (CVI). The earliest symptom is a heavy, tired, or achy feeling in your legs, especially after standing for long periods. You might not see anything wrong at first.
As CVI progresses, visible signs appear in stages. Spider veins come first, followed by more noticeable swelling. Eventually, the pressure in your veins becomes high enough to burst tiny capillaries near the skin surface, causing reddish-brown discoloration around the ankles. In advanced cases, the skin breaks down into open sores called venous ulcers, typically near the ankles. These ulcers heal slowly and can become painful, especially if infected. Compression stockings and leg elevation are the mainstays of management, with procedures to close damaged veins reserved for more severe cases.
Joint Problems That Refer Pain
Hip and knee arthritis can cause leg pain in places you wouldn’t expect. Hip arthritis, for example, is classically felt in the groin, but a study of patients awaiting hip replacement found that 69% also reported pain at the front of the knee, and 47% had pain below the knee. This happens because the hip and knee share overlapping nerve pathways, so the brain can misinterpret where the signal is coming from.
This referral pattern creates a common diagnostic trap. If your knee hurts but knee imaging looks normal, the problem may actually be in your hip. The reverse is less common but possible. Joint-related leg pain typically worsens with weight-bearing activity, feels stiff in the morning, and gradually improves with gentle movement over the first 20 to 30 minutes of your day.
Warning Signs That Need Immediate Attention
Most leg pain is manageable at home with rest, ice, compression, and elevation. But certain patterns signal a potential emergency. Acute limb ischemia, where blood flow to the leg is suddenly and severely blocked, produces five classic warning signs: rapidly worsening pain, loss of pulse in the foot, pale or white skin, numbness or tingling, and inability to move the foot or toes. This is a surgical emergency.
Other combinations that warrant urgent evaluation include sudden one-sided leg swelling with warmth (possible DVT), leg pain with chest pain or shortness of breath (possible clot that has traveled to the lungs), and any leg pain accompanied by fever and red, hot skin (possible infection). Leg pain that wakes you from sleep repeatedly, gets worse over weeks despite rest, or comes with unexplained weight loss also deserves prompt investigation rather than a wait-and-see approach.