Diabetes

Diabetic amyotrophy: thigh pain and weakness in diabetes

Diabetic amyotrophy is a rare nerve condition of diabetes. Sudden, severe pain in the hip, buttock or thigh, usually on one side, is followed within weeks by weakness and shrinking of the thigh muscles. It mostly affects people over 50 with type 2 diabetes, often early in their diabetes and often with weight loss. Most people improve, but slowly, over months to a few years.

Written by the Managing Neuropathy editorial team under the direction of Dr. Tom Biernacki, DPM, FACFAS · Clinical review pending · Last updated 11 October 2026

An older man exercising at home, his arms held straight out in front of him

The short answer. Diabetic amyotrophy, also called diabetic lumbosacral radiculoplexus neuropathy or proximal diabetic neuropathy, affects about 1 in 100 people with diabetes. It usually starts with deep, severe pain in one hip or thigh, followed by weakness that makes rising from a chair, climbing stairs and walking hard, and many people lose weight. The cause is thought to be inflammation of the tiny blood vessels that feed the nerves, not simply high blood sugar. No single test confirms it, so doctors use nerve tests and an MRI to rule out look-alikes, such as a pinched nerve in the back. No treatment is proven to shorten it, so care focuses on pain relief, steady blood sugar control and physical therapy. Pain usually eases within about a year, and strength comes back slowly over months to years, though some weakness often remains.

What diabetic amyotrophy is

Diabetic amyotrophy is damage to the nerves that run from the lower spine to the hip and thigh. It affects three places at once: the nerve roots leaving the lower spine, the lumbosacral plexus (a network of nerves in the pelvis that supplies the leg), and the leg nerves themselves. That is why specialists call it diabetic lumbosacral radiculoplexus neuropathy, or DLRPN. You may also see it called proximal diabetic neuropathy, diabetic polyradiculopathy, Bruns-Garland syndrome or, in older writing, diabetic femoral neuropathy.

“Amyotrophy” means muscle wasting. The muscles hit hardest are usually at the front of the thigh (the quadriceps, which straighten the knee), along with the hip-flexor and inner-thigh muscles. That is very different from the usual diabetic neuropathy, which starts in the toes of both feet and mainly affects feeling, with numbness, tingling or burning. The four types of diabetic neuropathy.

It is usually a single episode: it builds up over weeks to months, levels off and then slowly improves. The same illness can occur without diabetes, where it is called lumbosacral radiculoplexus neuropathy and behaves almost identically. Similar attacks can also affect the nerves of the neck and arm, or of the trunk, where they cause chest-wall or belly pain.

Who gets it

It affects roughly 1 in 100 people with diabetes, mostly people with type 2 diabetes who are over 50, and men more often than women. In a review of 115 published cases, 95 percent had type 2 diabetes and the median age was 62.

It often appears early in diabetes. In that review, people had had diabetes for a median of 3 years, and their median A1c was 8.0 percent: raised, but not extreme. It can even occur in diabetes that has not yet been diagnosed. So diabetic amyotrophy does not mean your diabetes was badly managed.

In a Mayo Clinic study of everyone diagnosed in one Minnesota county over 16 years, about 4 people per 100,000 developed this kind of nerve attack each year, with or without diabetes. Two-thirds of them had diabetes, compared with about 1 in 5 people of the same age and sex. About a third of the episodes followed a trigger: starting intensive diabetes treatment, surgery, or a big change in exercise or lifestyle.

Because GLP-1 medicines can bring down A1c and weight quickly, they are being watched as a possible trigger. In 2025, neurologists described three men taking a GLP-1 medicine who developed it around the time they lost 20 to 40 pounds over a few months. Two of them also had a sharp fall in A1c. Three cases cannot show that the medicine caused it, so don’t stop a medicine because of this. If you develop new thigh pain or weakness, tell your prescriber.

Symptoms, and how it unfolds

Sudden, severe pain deep in the hip, buttock or thigh, sometimes in the lower back, usually on one side. Pain is usually the first symptom. In a review of published cases, it was one-sided in 70 percent.
Weakness within weeks. Getting up from a chair and going up or down stairs become hard, and the knee may buckle. Many people need a cane, crutches or a walker for a while.
Muscle wasting. The thigh visibly shrinks, and the knee-jerk reflex is often weak or lost.
Weight loss. Up to two-thirds of people lose weight around the time it starts, often more than 10 pounds and sometimes much more.
Spread to the other leg. In about half of people the other leg becomes involved, usually within 6 months, but the two sides usually stay unequal.
Other symptoms. Weakness is usually worst above the knee, but the lower leg can be involved too, sometimes with foot drop. Some people have numbness or tingling, and some have autonomic symptoms, such as dizziness on standing or bowel, bladder or sexual problems.

Symptoms usually worsen over weeks to months, level off, then slowly improve. At its worst it can be disabling: in the Minnesota study, about 1 in 4 people were using a wheelchair when they were diagnosed. A few people have weakness without pain.

What causes it

The leading explanation is inflammation of the tiny blood vessels that feed the nerves, called microvasculitis. The inflammation interrupts the blood supply to parts of the nerves and injures them. Nerve biopsies from people with the condition show this inflammation, and the immune system is thought to drive it.

Diabetes is the strongest risk factor, but poor control is not required. It has been described soon after very high blood sugar was brought under good control, and rapid changes in blood sugar are one of the recognized triggers.

It is a different condition from treatment-induced neuropathy of diabetes, sometimes called insulin neuritis. That is a small fiber neuropathy that causes nerve pain, autonomic symptoms or both, starting within 8 weeks of a large, fast fall in A1c: 2 percentage points or more over 3 months. Diabetic amyotrophy, by contrast, causes deep thigh pain followed by weakness, usually more on one side.

How it is diagnosed

There is no single test for diabetic amyotrophy. Doctors recognize it from the story and the examination, and use tests mainly to confirm the pattern and rule out other causes:

Nerve conduction studies and EMG show nerve damage in a root-and-plexus pattern, often including the muscles beside the spine. They are most informative after about 3 weeks of symptoms. What the nerve test is like.
An MRI of the lower spine, sometimes with MRI or CT of the pelvis, rules out a pinched nerve, a tumor or bleeding.
Blood tests check blood sugar and A1c and look for other causes. They often include a blood count, a chemistry panel, an inflammation marker (ESR), vitamin B12 and a thyroid test.
Spinal fluid, if a spinal tap is done, usually shows raised protein.
A nerve biopsy is not routinely needed.

These conditions can look similar, and they are the reason a new bout of thigh pain and weakness needs a proper work-up:

Condition	What sets it apart
A pinched nerve root in the lower back	Back pain spreading down the leg, often changing with position. An MRI shows the compression.
Lumbar spinal stenosis	Leg pain or cramping that comes on with standing or walking and eases with sitting or bending forward.
Femoral nerve damage alone	Similar front-of-thigh weakness and knee buckling, but the nerve test shows one nerve, not a root-and-plexus pattern. Bleeding in the pelvis is one cause.
Meralgia paresthetica	Numbness, tingling or burning on the outer thigh only, with no muscle weakness.
Bleeding in the pelvis or abdomen	In people taking blood thinners, a pool of blood (hematoma) can press on the same nerves.
Cancer, infection or other inflammation	Tumors in the pelvis, radiation damage, shingles, infections and CIDP, a chronic inflammatory nerve disease, can mimic it. Imaging, blood tests and nerve tests help sort these out.

Pinched nerve or neuropathy: how to tell. Femoral nerve pain and weakness. Meralgia paresthetica.

Treatment

No treatment has been proven to shorten diabetic amyotrophy, and most people improve even without specific treatment. Care focuses on four things:

Pain relief. The pain is usually treated with the medicines used for painful diabetic neuropathy. For that, a 2017 American Diabetes Association statement suggests pregabalin or duloxetine first, gabapentin as an alternative, and tricyclic antidepressants such as amitriptyline with caution, and it does not recommend opioids as first- or second-line drugs. A 2022 American Academy of Neurology guideline also lists tricyclic antidepressants and sodium channel blockers among the first choices, and it says opioids should not be used for painful diabetic neuropathy. Simple pain relievers may help, but ask your clinician or pharmacist before using anti-inflammatory ones such as ibuprofen or naproxen, which can harm the kidneys. Very severe pain sometimes needs a hospital stay. Nerve pain medicines compared.
Steady blood sugar control, along with blood pressure and cholesterol. It is recommended, but rapid swings are a recognized trigger, so agree on targets and pace with your diabetes team rather than making sudden big changes on your own.
Physical and occupational therapy to rebuild strength and keep you moving and independent. A walker, wheelchair or brace may be needed for a while.
Fall and foot protection. If foot drop develops, an ankle-foot brace holds the foot up. Clear floors and good lighting on stairs lower the risk of falls. If your feet are also numb from ordinary diabetic neuropathy, check them every day. Choosing a foot drop brace.

Steroids and IVIG. Because the nerve damage looks inflammatory, specialists have tried immune treatments. A Cochrane review found no evidence from randomized trials for or against any of them. The only completed trial, of intravenous (IV) methylprednisolone, a steroid, in 75 people, was never fully published; reports of it say the steroid eased pain and other nerve symptoms but did not improve strength more than a placebo. A UK neurology review says pulsed IV methylprednisolone may help pain if given within 2 to 3 months of onset. Steroids also raise blood sugar, which matters when you have diabetes. IVIG, an infusion of antibodies from donated blood, is not an established treatment.

Recovery and outlook

Most people improve, but slowly. Pain usually eases first, typically within a year. Strength comes back later and more slowly, over many months to a few years. The active phase of the illness lasts from a few months to about two years.

Full recovery of strength is not guaranteed. One review puts it at only 10 to 20 percent, and many people keep some weakness, pain on exertion or difficulty with stairs. Another review is more hopeful, saying most people end up with normal or near-normal strength. In the Minnesota study, after a median of 8 months, a little over half had measurably improved and about 1 in 8 still used a wheelchair. Cleveland Clinic puts wheelchair use at around 10 percent two years after symptoms start.

Two practical points. Thigh size is not a reliable guide to recovery, because wasted muscle can be replaced by fat. And it usually happens only once, although some people have a second episode. Can neuropathy be reversed?

When to get help urgently

Call 911 or go to an emergency department for numbness around the genitals or anus, new trouble starting or controlling urine or bowel movements, or weakness or numbness in both legs that is severe or getting worse. These can be signs of serious pressure on the nerves at the base of the spine.
Call 911 for sudden numbness or weakness of the face, arm or leg, especially on one side, sudden confusion or trouble speaking, seeing, walking or keeping your balance, or a sudden severe headache with no known cause. These can be signs of a stroke.
Call 911 for chest pain or discomfort that lasts more than a few minutes or goes away and comes back, especially with shortness of breath or feeling weak, light-headed or faint. This can be a heart attack. Don’t assume new chest pain is nerve pain, even though this condition can affect the chest wall.
Go to an emergency department for weakness that is spreading over hours or days, and call 911 if you also have trouble breathing or swallowing.
Seek care right away for back or hip pain with a fever or chills, and for back pain after a fall or injury.
Go to an emergency department for sudden severe groin, thigh or flank pain with leg weakness if you take a blood thinner. This can be a sign of internal bleeding.
Get seen promptly for any new bout of severe thigh pain and weakness, or for weight loss you can’t explain. These need checking rather than an assumption that they are diabetic amyotrophy.
See your doctor or foot doctor right away for a blister, sore or ulcer on a numb foot. Don’t wait for your next appointment.

Common questions

How long does diabetic amyotrophy last?

Symptoms usually build up over weeks to months, and the illness stays active for a few months to about two years. Pain typically eases within a year, and strength returns slowly over many months to a few years. Recovery is often incomplete.

Is diabetic amyotrophy permanent?

Usually not entirely. Most people improve a great deal, often without specific treatment, but full recovery of strength is not guaranteed, and many people keep some weakness or pain on exertion. Physical therapy helps you make the most of the recovery.

Can diabetic amyotrophy affect both legs?

Yes. It usually starts in one leg, and in about half of people the other leg becomes involved, usually within 6 months, though the two sides usually stay unequal. Less often, similar attacks affect the nerves of the arms or the trunk.

Can diabetic amyotrophy come back?

It usually happens only once, but some people have a second episode. New pain or weakness after recovery should be checked rather than assumed to be a recurrence.

Does diabetic amyotrophy mean my diabetes was badly controlled?

No. It often appears early in diabetes, when A1c is only moderately raised, and sometimes soon after blood sugar has been brought down quickly. Diabetes is the main risk factor, but poor control is not required.

Thigh pain and weakness,
and diabetes?

Diabetic amyotrophy is diagnosed and followed by a neurologist and your diabetes team. Weak legs and numb feet also call for a foot examination, protective footwear, bracing and help with falls, and Dr. Biernacki’s Michigan practice can help with that part.

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Dr. Tom Biernacki, DPM, FACFAS

Dr. Tom Biernacki, DPM, FACFAS is a double board-certified foot and ankle surgeon (ABFAS and ABPM) and a Fellow of the American College of Foot & Ankle Surgeons. He is the founder of Balance Foot & Ankle in Howell and Bloomfield Township, Michigan, where peripheral neuropathy, diabetic foot risk and loss of protective sensation are part of his weekly clinic. His patient education videos have drawn more than 950,000 subscribers on YouTube. Managing Neuropathy is written by its editorial team under his direction, to put the explanation he gives in the exam room in front of the people who cannot get to one — including when a product is worth buying and when it is not.