Numbness in the legs: causes, what to do and is it your veins?
Varicose veins rarely cause true leg numbness: nerves, the spine, diabetes or arteries are far more often to blame. How to tell the causes apart, who to see first and how to rule out a vascular cause.
Varicose veins on their own rarely cause true numbness in the legs: diseased veins give heaviness, evening swelling and night cramps. Legs usually go numb because of the nerves: pressure from a posture, problems in the lower back, or polyneuropathy in diabetes, and less often because of narrowed arteries. If the numbness keeps coming back, start with a general practitioner or a neurologist. If the foot is cold, your calves hurt when you walk, or you have visible veins, start with a vascular surgeon and an ultrasound of the leg veins and arteries.
A familiar picture: your leg goes numb from the knee down when you sit with your legs crossed, and there is a twisted vein on your shin. Most of the time that vein is just a neighbour, and the pins and needles come from a nerve. Let us work out who you should see first.
Can varicose veins cause leg numbness?
My answer as a vascular surgeon: usually there is no direct link. Blood pooling in widened veins feels different:
- heaviness and tiredness in the lower legs by the evening;
- a bursting, humming or aching feeling that eases after resting with your legs up;
- swollen ankles and marks left by sock elastic;
- night cramps in the calves;
- itchy skin over the affected veins.
Chronic venous insufficiency can cause tingling or restlessness in the legs. But persistent numbness, where the skin barely feels a touch, is not a typical venous symptom. If it is there, I look for another cause, even when the varicose veins are obvious.
Veins can be involved in three situations: compression stockings that are too tight or the wrong size, severe swelling that squeezes the tissues, and the first weeks after vein surgery.
Myth: numbness is a sign of varicose veins, so the veins need treating
If the numbness comes from the spine or from polyneuropathy, vein surgery will not take it away, and valuable time is lost. Vein tablets and creams do not repair a nerve either.
The opposite mistake is to blame everything on the nerves and never check the arteries, especially in smokers, people with diabetes and older patients. When varicose veins need treatment, they are treated for heaviness, swelling and to prevent complications, not for numbness.
Why do my legs go numb? Possible causes
Numbness is a signal from a nerve: either the nerve itself is affected, something is pressing on it, or it is not getting enough blood. The main groups of causes:
- Nerve pressure from posture. The peroneal nerve wraps around the outer side of the knee just under the skin and is easy to squeeze when you sit cross-legged or squat. The outer shin and the top of the foot go numb, and it passes once you change position. If your foot starts to slap the floor when you walk, see a neurologist.
- The spine. A disc herniation or narrowing of the spinal canal in the lower back presses on nerve roots: the numbness runs in a strip down the leg, often with shooting pain from the lower back.
- Polyneuropathy. The small nerves of the feet are affected, usually on both sides, in a sock pattern: burning, tingling and numbness that get worse at night. Common causes are diabetes, heavy drinking, vitamin B12 deficiency and thyroid disease.
- Arteries. Atherosclerosis narrows the leg arteries, so nerves and muscles do not get enough blood: a cold, pale foot, calf pain when walking and a weak pulse in the foot. More on the page about atherosclerosis of the leg arteries.
- Outside pressure. Tight shoes, skinny jeans, a tight waistband or belt: when the nerve is squeezed near the bony point at the front of the pelvis, the outer thigh goes numb and burns.
- Pregnancy. The growing bump, swelling and extra load on the lower back can compress nerves: the outer thigh often goes numb, or pain shoots down the leg. Tell your obstetrician. Swelling and pain in one leg during pregnancy is a reason to rule out a blood clot the same day.
Numbness below the knee or from knee to foot: what the pattern tells you
Where and when the numbness appears is the main clue to which doctor to start with. This is not a diagnosis, it is a route:
| How it goes numb | Most likely system | Who to start with |
|---|---|---|
| After long sitting with legs crossed, passes after changing position | Nerve compression | Change the habit; if it keeps happening or the foot feels weak, a neurologist |
| Burning and numbness in both feet in a sock pattern, worse at night | Polyneuropathy, often with diabetes | GP or endocrinologist, then a neurologist |
| Numbness in a strip down the leg with shooting pain from the lower back | Spine, nerve roots | Neurologist |
| Cold, pale foot; calves go numb and ache when walking and settle within a few minutes of stopping, even standing | Arteries | Vascular surgeon |
| Legs go numb when walking and ease only when you sit down or lean forward | Narrowing of the spinal canal in the lower back | Neurologist |
| Heaviness and a bursting feeling by evening, swelling, visible veins | Veins | Phlebologist, vein ultrasound |
| A patch of numb skin after EVLA | Irritation of a skin nerve | The surgeon who operated |
Legs go numb when lying down
If your legs go numb while you lie on your side or back and the feeling passes when you turn over, posture and nerves are the usual reason.
A warning sign is numbness and pain in the foot at night that ease when you hang the leg over the side of the bed. This is how a significant problem with arterial blood flow shows up, and you need to see a vascular surgeon without delay. I covered other night-time sensations, such as pain, burning and cramps, in the article on why legs hurt at night.
Leg numbness after EVLA: why it happens and what to do
In endovenous laser ablation (EVLA) the vein is sealed with a laser from the inside. The saphenous nerve runs next to the great saphenous vein, and the sural nerve next to the small saphenous vein. Heat can irritate them and leave a patch of numbness, tingling or extra sensitivity: on the inner side of the shin and ankle after surgery on the great saphenous vein, and on the back of the calf and the outer edge of the foot after surgery on the small one.
The numbing fluid injected around the vein protects the surrounding tissue, so this is uncommon. In the first hours, numbness is simply the local anaesthetic at work. If a patch lasts longer, feeling usually comes back over weeks or months.
What to do:
- tell the surgeon who operated; outline the patch with a pen and take a photo so you can track changes;
- do not warm the patch with a hot-water bottle or rub it: skin with reduced feeling burns easily;
- if your toes go numb under the compression stocking or bandage, loosen it and contact your doctor.
Call your surgeon urgently if the numbness comes with swelling of the whole lower leg, a bursting pain in the calf, weakness of the foot or cold, pale toes. Normal recovery in the first weeks is described in the article on recovery after EVLA day by day.
Numb legs: what to do today and who to see
Answer six questions and write the answers down; they will save time at your appointment:
- 1Is it one leg or both?
- 2When does it happen: in a particular position, when walking, at night or all the time?
- 3Does it pass within a few minutes of changing position?
- 4Is one foot colder and paler than the other, and do your calves ache when you walk?
- 5Do you have evening swelling and visible veins?
- 6Do you have diabetes, do you smoke, do you have lower back pain?
A simple check at home: stroke the same areas of both shins and feet with a cotton pad. If the touch feels weaker on one side, or as if through fabric, that is numbness, a signal from a nerve or from blood flow. If the feeling is the same on both sides but the legs are heavy, the complaint is more likely venous.
Compare your answers with the table above. If the numbness appears only in one position and passes quickly, start with habits: do not sit cross-legged, and get up and walk every hour. If both feet are numb and you have diabetes or suspect it, a GP will check your blood glucose and HbA1c and, if needed, vitamin B12 and thyroid hormones.
Until the cause is clear, do not put on compression stockings just in case if your foot is cold or has poor feeling: with impaired arterial flow and reduced sensation, compression can damage the skin. It is prescribed only after the arteries have been checked, and with severe arterial narrowing it is not prescribed at all. If you have diabetes, check your feet every day; more in the article on varicose veins and diabetes.
When to see a doctor urgently
- Sudden numbness or weakness on one side of the body, a drooping face or slurred speech: call an ambulance immediately (103 in Uzbekistan). These are signs of a stroke.
- A leg suddenly goes numb, cold, pale and painful, and the toes barely move: call an ambulance. This is how an acute arterial blockage shows up, and every hour counts.
- Numbness in the groin and between the legs, trouble passing urine or controlling the bowels, increasing weakness in the legs: go to hospital urgently. The nerve roots may be compressed.
- Numbness rising quickly up the legs over hours or days, with weakness: see a doctor the same day; if breathing or swallowing becomes difficult, call an ambulance.
- Swelling and pain in one leg, especially in the calf: a blood clot must be ruled out the same day. If sudden shortness of breath, chest pain, coughing up blood or fainting appear, call an ambulance right away.
- Pain or numbness in the foot at night that eases when you hang the leg off the bed: see a vascular surgeon without delay, within the next few days.
- A small wound, redness or darkening of a toe appears on a numb foot: see a doctor within 24 hours, because with reduced feeling an infection is easy to miss.
What a vascular surgeon will check
At the appointment I ask about your symptoms, compare the temperature and colour of both feet and check the pulses in the feet. Then I do a duplex vein ultrasound, and an arterial scan if needed: it shows reflux, clots and arterial narrowing. If I suspect narrowed arteries, I measure the ankle-brachial index, comparing blood pressure at the ankle and the arm; in diabetes the arteries can be stiff, so the pressure is also measured on a toe. Sometimes other tests are needed, for example CT angiography.
If the vessels are fine, that is a result too: the cause is more likely in the nerves, and I refer you to a neurologist or GP, who arrange tests of the nerves and spine. If varicose veins are found, I explain which symptoms their treatment can relieve and which it cannot.
The bottom line: numb legs are a reason to find the cause, not to rush into treating your veins. The vascular side of the question is usually settled by an examination and a duplex ultrasound of the leg veins and arteries; the rest is for a GP and a neurologist.
Frequently Asked Questions
My legs go numb: what can I do at home?
Change position, loosen tight shoes, a belt or compression stockings, and walk around: numbness from nerve compression usually passes within a few minutes. Do not warm numb skin with a hot-water bottle, as it burns easily. If the numbness keeps returning, note when and where it happens and see a doctor; sudden numbness with a drooping face or slurred speech means calling an ambulance.
What causes numbness from the knee to the foot?
Most often it is compression of the peroneal nerve from posture, a pinched nerve root from lower back problems, or polyneuropathy, for example in diabetes; less often it is narrowing of the leg arteries. Treatment depends on the cause: start with a GP or neurologist, or with a vascular surgeon if the foot is cold and your calf hurts when you walk. The causes are the same in men and women, but older men who smoke should be especially careful to have their arteries checked.
Is leg numbness normal with varicose veins?
Numbness is not typical of varicose veins, which cause heaviness, swelling and cramps. If your legs go numb and you have varicose veins, the doctor looks for another cause, such as the nerves, spine or arteries, and checks whether compression stockings are too tight.
My leg is numb after EVLA: will it go away?
In most cases, yes. In the first hours it is the local anaesthetic; if a numb patch lasts longer, a skin nerve next to the treated vein is usually irritated, and feeling returns over weeks or months. Tell your surgeon, and loosen the stocking if your toes go numb under it. Numbness of the whole leg, swelling of the lower leg, calf pain, a weak foot or cold toes mean contacting your doctor urgently.
Why do my hands and feet go numb?
When both hands and feet go numb, veins are almost never the cause: it is more often polyneuropathy (diabetes, vitamin B12 deficiency, alcohol) or a spine problem. Start with a GP and a neurologist; sudden numbness of an arm and a leg on the same side is a reason to call an ambulance.
This article is for informational purposes only and does not replace a consultation with a qualified physician. If you are experiencing symptoms, please see a specialist.