Leg pain has dozens of possible causes, ranging from something as simple as overworked muscles to circulation problems, nerve compression, or joint disease. The cause usually depends on where exactly the pain is, what it feels like, and what makes it better or worse. Most leg pain is musculoskeletal, meaning it comes from muscles, tendons, or bones, and resolves on its own. But some types signal a problem that needs prompt attention.
Muscle and Joint Causes
The most common reason for leg pain is plain muscle strain or overuse. You pushed harder during a workout, walked more than usual, or spent hours on your feet. This kind of pain tends to feel sore and achy, affects a specific muscle group, and improves within a few days with rest.
Muscle cramps are another frequent culprit, especially at night. These sudden, involuntary contractions hit the calf most often and can wake you from sleep. Despite what you may have heard, there’s no proven link between electrolyte levels and routine muscle cramps. Blood tests typically can’t explain them. Cramps are more common in older adults, during pregnancy, and after intense exercise, but they often have no identifiable trigger.
Joint problems cause a different kind of pain. Osteoarthritis, the wear-and-tear type, commonly affects knees and hips and creates stiffness that’s worst in the morning or after sitting for a while. Gout tends to strike suddenly and intensely, often in a single joint. Inflammatory types like rheumatoid or psoriatic arthritis can cause pain, swelling, and warmth around joints in the legs.
Tendinitis (inflamed tendons) and bursitis (inflamed fluid-filled cushions near joints) usually develop from repetitive motion. Shin splints, Achilles tendon pain, and runner’s knee all fall into this category. The pain typically worsens with the activity that caused it and eases with rest.
Circulation Problems
When leg pain is caused by blood flow rather than muscles or joints, it tends to follow distinct patterns. Two vascular conditions are especially worth knowing about.
Peripheral artery disease (PAD) causes cramping or aching in the legs during physical activity, like walking. The pain usually hits the calves, though it can affect the thighs or buttocks. It starts at a predictable point during exercise and goes away within minutes of resting. This happens because narrowed arteries can’t deliver enough blood to working muscles. As PAD progresses, the pain can begin showing up at rest too.
Chronic venous insufficiency is the opposite problem: blood has trouble flowing back up from the legs to the heart. This creates a heavy, tired, achy feeling in the legs that worsens through the day, especially if you’ve been standing. Visible signs include varicose veins, swelling around the ankles, and skin changes near the lower legs. Elevating your legs brings relief because gravity helps the blood return.
Nerve-Related Leg Pain
Nerve problems produce a distinctive type of leg pain that feels different from a sore muscle. Two of the most common are sciatica and peripheral neuropathy, and they’re worth telling apart because their behavior and treatment differ significantly.
Sciatica happens when a nerve root in the lower back gets compressed, usually by a herniated disc or a narrowing of the spinal canal. The pain shoots from the low back or deep in the hip down the back of one leg. It’s typically one-sided. Sitting often makes it worse, and many people notice it flares in the morning but eases as they move around during the day. The sensation can range from a dull ache to sharp, electric jolts, sometimes with numbness or tingling along the nerve’s path.
Peripheral neuropathy, by contrast, affects the nerves in the legs and feet themselves rather than the spine. It causes numbness, tingling, or burning that’s usually present in both feet and doesn’t change much with position or movement. People with neuropathy often become hypersensitive to touch, finding even the pressure of socks or shoes uncomfortable. Diabetes is the most common cause, but it can also result from certain medications (particularly cholesterol-lowering statins), vitamin deficiencies, or alcohol use.
Less Obvious Causes
Some causes of leg pain aren’t immediately intuitive. Low vitamin D levels can produce vague, widespread aching in the legs and bones. Imbalances in calcium or potassium can contribute to muscle discomfort and cramping. Certain medications cause leg pain as a side effect. Statins are the best-known example, sometimes causing muscle soreness or weakness that ranges from mild to severe.
Spinal stenosis, a narrowing of the space around the spinal cord, can cause leg pain, numbness, or weakness that gets worse with walking or standing and improves when you sit or lean forward. It’s most common in people over 50 and is often confused with PAD because both cause pain during walking that stops with rest. The key difference: PAD pain eases simply by standing still, while spinal stenosis pain typically requires sitting down or bending forward.
In children and adolescents, growing pains cause aching in the legs, usually in the thighs, calves, or behind the knees, most often in the evening or at night. They’re harmless and resolve on their own.
How to Tell What Type You Have
A few questions can help you narrow down the cause before you see anyone about it:
- Where is the pain? Pain in a specific muscle suggests strain or overuse. Pain that travels from your back down one leg points toward sciatica. Pain in both feet and lower legs that’s constant suggests neuropathy. Pain in a single joint suggests arthritis or injury.
- When does it happen? Pain that comes on during walking and stops with rest suggests a circulation or spinal problem. Pain that’s worse in the morning and loosens up suggests joint stiffness. Night cramps that hit suddenly and resolve within minutes are usually benign.
- What does it feel like? Shooting or electric pain is usually nerve-related. Deep aching or heaviness points toward vascular causes. Sharp pain at a specific spot after an injury could mean a tear, fracture, or sprain.
Pain lasting longer than three months is considered chronic and is more likely to need medical evaluation and a structured treatment plan rather than simple rest.
Signs That Need Prompt Attention
Most leg pain isn’t dangerous, but certain combinations of symptoms suggest something more serious. A blood clot in a deep leg vein (DVT) is one of the most important to recognize. Warning signs include swelling, redness, and warmth in one lower leg, especially after prolonged sitting like a long flight or car ride. Recent surgery, cancer, or extended bed rest all increase the risk.
Seek care quickly if you notice any of the following:
- One leg is swollen, pale, or noticeably cooler than the other
- Pain, swelling, redness, and warmth concentrated in the lower leg
- You can’t walk or bear weight on the leg
- You heard a pop or grinding sound during an injury
- Signs of infection: redness, warmth, tenderness, or fever above 100°F
- Swelling in both legs along with difficulty breathing
- Calf pain that started after extended sitting
Any serious leg pain that starts suddenly with no obvious cause also warrants a prompt evaluation, even if none of the above red flags are present.