Leg Weakness – Causes and Treatment

Leg weakness is a serious symptom which is commonly ignored by many people. Leg weakness is highly based on ones own perception, so many people may not even realize that they have leg weakness. However, for practical purposes it is the first sign of paralysis because of nerve compression in the lower back. Leg weakness is frequently accompanied by loss of touch sensation and shooting pain, which generally come before the leg weakness. Thus, loss of sensation or shooting pain can be taken as an alarming signals, which tell us that leg weakness is on its way. Hence, it should be taken very seriously and any prompt medical help should be sought. This is especially important for people having low back problems, who have a greater chance of getting leg weakness.

What is leg weakness ?

Leg weakness should not be confused with tiredness or a heavy feeling that one gets after a long day of work. It is the weakened strength of the leg muscles, which is manifested by inability to do certain movements with the foot or leg. Leg weakness should also not be confused with a muscle cramps or arthritis which cause a painful inability to move the foot or leg. Leg weakness also interferes with walking especially when it is involving the foot muscles. This is known as foot drop, in which a person unable to lift the foot upwards.

How does leg weakness occur ?

The leg is supplied by nerves which come out of the spinal cord and back bone in the lower part of the back. These nerves travel all the way from the lower back to the various parts of the leg, imparting it touch sensation and movement. The vertebrae in the lower part of the back are a common site of diseases like slip disc (slipping of cartilage intervertebral disc (Picture 1, 2) which normally lies between two vertebrae causing compression of nerves or spinal cord), sciatica (compression of a nerve bundle as it comes out of the hip bones), and leprosy (fibrosis of superficial nerves near the skin). The nerve damage caused by these diseases results in abnormal functioning of the parts supplied by the nerves (generally muscles and touch sensation). Consequently, when a large part of the leg looses its nerve supply, like a major muscle, it makes the person unable to do the movement performed by this part (muscle) or makes the part insensitive to touch.

Picture 1: Intervertebral disc, top view
(source: Chiro Org Images)

Picture 2: Intervertebral disc, side view
(source: Chiro Org Images)

Why is leg weakness an emergency ?

Nerve damage is almost always permanent as nerve tissue does not grow back easily. One can only prevent further damage by identifying its cause and taking treatment, but the damaged nerve can not be repaired. There is a window period of a few days between getting leg weakness and the nerve being permanently damaged. Thus, if leg weakness is treated during this period, the permanent damage to nerves can be avoided and leg movements can come back. So it is very important to seek medical attention and perform the diagnostic tests early, to complete treatment within this window period.

Diagnosis of Leg weakness

Leg weakness most commonly arises from nerve compression in the lower back. Hence, pain in the lower back region should not be ignored, especially if it is longstanding. The shooting pain, which travels from the lower back to the knee or the ankle, is because of the irritation of the nerves caused by compression. This is also called sciatica because the nerve coming out of the hip bone is called the sciatic nerve, which divides into smaller nerves which supply the leg muscles and also provide touch sensation.
The initial evaluation consists of evaluation of the leg muscles by a doctor or a physiotherapist. The doctor would ask you to do several simple movements and measure the strength of your movements by opposing the movement with his hand. The touch sensation is also tested with a cotton wisp or a pin to find out the exact region of sensory loss.
This helps in locating the probable site of the nerve compression so that further tests can be directed towards that region.
The common diagnostic tests employed for investigation of causes of leg weakness are:

Picture 3: Spondylolisthesis on X-ray
(source: Wikimedia)

  1. X-rays of lower back, which rule out bony abnormalities like fractures or spondylolisthesis (forward or backward slipping of a vertebra)(Picture 3). This is the primary investigation for all causes and is especially important when one has had a traumatic incident like a fall or a road accident.
  2. MRI helps in diagnosis of injuries and abnormalities like slip disc, intervertebral disc protrusion, nerve compression, and so on. Soft tissues which cannot be seen on x-rays can be seen on MRI so the causes related to them can be accurately diagnosed.
  3. Nerve conduction studies are used in diseases, which are difficult to visualize on X-ray or MRI like leprosy, syphilis, etc., and which are confined to the nerves. In this test, small electrodes are stuck to the different parts of the body and measurements are made of the electrical activity of the nerves of that part.

After these investigations and the physical examination, leg weakness can be attributed to compression of spinal cord (Picture 4), compression of spinal nerve (Picture 5 ), or local nerve disease.

Picture 4: Spinal Cord Compression
(source: Wikimedia)

Picture 5: Spinal nerve compression
(source: Wikimedia)

Compression of spinal nerve or spinal cord is mostly due to intervertebral disc protrusion. However, some other causes for the same are spinal tumor, sciatica, dislocation of vertebra (spondylolisthesis), fracture of vertebra, and spinal stenosis.

Local nerve diseases are leprosy, syphilis, nerve cut injury, or neurofibroma.

Treatment of Leg weakness

Leg weakness due to local nerve disease is treated as per the disease condition. Most of these diseases are treated with medicines and do not require surgery. However, the medicines have to be continued for many months, or sometimes even a couple of years.

Leg weakness caused by spinal cord or nerve compression are treated by surgery more often than by medicines. The diseases like sciatica and fracture of vertebra are generally treated with bed rest and painkillers for a period of 6 weeks. This is followed by gradual exercises and physical therapy which strengthen the muscles. The other medicines which are helpful in reducing the pain are muscle relaxants and neurovitamins. As long as the treatment program is religiously followed there are no complications. However, if not followed, one may end up being a paraplegic for life.

The surgery for spinal tumor or intervertebral disc protrusion should be taken only when leg weakness or loss of sensation is present. A person also has to wear an orthosis (a belt for the back which gives support and restricts some movement)(Picture 6) after surgery for a period of 6-8 months until the bones and muscles regain their strength. Simple low back pain or shooting pain should not be taken as an alarming sign for surgery. They should only be pointers towards a medical evaluation for leg weakness.

Picture 6: Orthosis for lower back
(source: Wikimedia)

The surgery of spinal cord or vertebral column is not at all risk-free. There are chances that one may end up in paralysis after the surgery. It is also expected from the patient in writing that one is aware of this disastrous consequence and is still ready for the surgery. In the presence of leg weakness, surgery is a logical choice as one is eventually going to end up in paralysis without the surgery. But in the absence of leg weakness, there is still time and one can try medicines and physical therapy for improvement.

Related Articles:

Sciatic Nerve Pain – Causes and Symptoms

Leg Numbness, Tingling Feet and Toes

About Dr Gauresh (69 Articles)
An orthopedic surgeon trained in JJ Group of Hospitals and Grant Medical College. I have worked in this field for the past 3 years and have significant clinical experience to guide students and patients on any topic in orthopedics.
  • Muhammad Tariq Pakistan

    Sir!
    My legs are so weak. I can’t run. I can’t walk softly. I can’t go up on stairs. And when I try to walk fast I fell down & after fell down I can’t get up without any help. I am worried by this problem.

  • Dr Gauresh

    this is a very serious issue … consult an orthopedic surgeon immediately and get an MRI done urgently …
    or else u could develop paralysis of both your lower limbs…

  • Jawahar

    Hi,

    Im not able to walk for more than ten minutes,if i continue my walking my left leg gets numb in footer section of my body. Also sometimes my left leg alone gets numb problem. Consulted doctor and checked for diabetes and complete master health checkup. Results are positive.

    Please someone guide me on what steps i have to take to resolve this problem.

  • Dr Gauresh

    hi viks3457,
    The problem with your disc is that your surgeon has not been able to fully remove the disc in all these years. And now you must be having further narrowing of the canal with the scar from previous surgeries. I would strongly suggest taking a second opinion from another well established orthopedic surgeon. The second reason might be other physical factors like your body weight and strength of your back muscles which need to be tailored with physical therapy to prevent recurrent disc prolapses.

  • snowflakes

    i am a diabetic type 1.Ive had a lot of pain (cramps) in my legs.I cant walk anywhere without having my legs tired.Both of my legs feel so weak and also my chest

  • Dr Gauresh

    If your sugar levels are under control then the cause of your cramps is nothing serious. You just need some muscle relaxant and some rest. If your sugar levels are not under control then you have to control the sugar level as that is a major reason for cramps in diabetics.
    Diabetics are known to have muscle weakness due to the nature of their disease. So if u exercise regularly to keep ur muscles active then you can prevent this easily.

  • mike

    i have had surgery for a bulging disk. everything went well but I got no relief from the numbness in my left foot and left leg weekness. I have seen two outstanding doctors and they know what to do for pain but not numbness.Had a second mri and it showed nothing putting pressure on any nurve. Now they want to do a nurve root block. what do I do and what should I do

  • Dr Gauresh

    I do not understand how a nerve root block can help in leg weakness or numbness that you have. But since the surgeon that you have visited is outstanding as you say then you may as well do as he or she says.

  • mary

    I have complete numbness in my left leg, and on going pain in both my feet. my back does not hurt but I am numb from my hip down on the left side. they tell me that my L4 and L5 are bulging. physio therpy is their answer. is it the answer and how long of treatment must I have?

  • Ravi

    Sir,
    After road accident my right portion swell & after test doctor’s tell that my right portion not working because of small clot in my right head and they suggest physio therapy. After taking therapy two month my right leg swell not finished, due to this difficulty occur when I am walking. Give me some advise/excercise to completely wash out swell.

  • Dr Gauresh

    It appears that u have had a stroke. This type of swelling is not related to any muscle dysfunction as its a part of brain that is at fault. Needless to say there is no such exercise to wash out a swelling. The only thing I can suggest is limb elevation while u sleep. So keep ur right leg over a couple of pillows so that it is higher than the rest of the body.

  • Dr Gauresh

    well yes physiotherapy is the answer. The exercises taught in physiotherapy are to be continued for life. Though u will have relief in around 6 months. But dont stop there. Keep doing those exercises regularly.

  • russelly

    Hi Doc,

    I recently had an episode where i lost control of my legs (weakness) while doing intense pushups and burpees with running short sprints in between. I recovered enough to continue running within 1 minute, but could not do the pushups without the weakness returning. Is there anything I can do between sessions to ease any nervous damage I may be initiating?

  • Dr Gauresh

    well weakness during workouts is not because of any nervous damage. This is just due to buildup of lactic acid in muscles and is temporary. So you can rest assured that this wont persist in the longer term.

  • Mir

    Dr. Gauresh,
    I had a knee surgery after developing osteoarthritis 10 years ago. My knee remained sore but I was able to walk with a stick. Now since last few months I have developed a shortness of breath. Also, my legs are very weak. Sometimes I fall down without having any idea of what happened. I fall back when sitting on the bed. I use a round pillow if I had to sit on the bed for a longer time.
    regards
    Mir

  • AmberA

    I just recently started having pain from my knees and lower also weakness. I’ve also been having pain on the left side of my stomach and a headache. Could it be because I don’t move enough

  • Dr Gauresh

    Pain in knees is definitely a consequence of not moving enough. I cant really comment on the headache and stomach aches. However, it would be of great help if u do exercises for your knees at least at home.

  • Dr Gauresh

    hi Mir,
    I have no knowledge of your surgical history, but I assume it must have been a replacement surgery for your knees.
    Loosing balance is possible since the prosthetic knee does not have a feedback mechanism to convey the joint position like a normal knee does. Even weakness of musculature is possible due to the laxity that develops after years of wear and tear, especially in a replacement that has lasted for 10 years.
    I suggest that you visit your replacement surgeon and evaluate the integrity of the prosthesis. Also it could be helpful if u take exercises to improve the tone of your thigh muscles.

  • PERRY

    Hi, I’m 37 y/o male, about 2 months back I started to feel unusual on my right leg. I sometimes feel a small pain on my lower back just near below the kidney area. About five years back, I had an injury on my right leg, doctor said its a torn ligament but I didnt undergo any medical procedure(just x-ray and MRI).I am also having piles for about 4 years now. But my main concern is my leg, sometimes feels so week after a long office work on my chair. But I can still run or do outdoor sport anytime..Its just that I’m having this unusual sensations..Thank you..hope you can advise me..

  • ShreeHari

    Hi,I am 38/male and have been experiencing about my legs and hands are getting numb,tingle very frequently since last 2 months and I have anus itching too,I have started gym since last few months for physical stretching and some muscles exersize because I had Knee problems before so my physiotherapist shows me some stretching exersize but it looks like it doesn’t work and I feel weekness in my legs too ,I meant I can run,walk but Knowingly or unknowingly I thought about my knee problems which occured in 2000 and I felt week ,I do play sport/cricket every sunday but I have been not feeling good as I used to ,so please guide me

  • Dr Gauresh

    I dont think this is related to any nerve compression or back disorder. It seems to be trivial and such sensations are normal. You may get evaluated for your piles cause it can give you those unusual sensations.

  • Dr Gauresh

    This could be related to the exercises. I suggest you give some more time for your body to settle in the exercise routine. Once the muscles of the body get used to it, it may feel better. As long as you can actively play cricket and do other stuff its all fine. Watch for any numbness in legs. If you get that then get an MRI LS spine for evaluation.

  • tamashcal

    I have had lower back pain for two years and have had a mri and xray and they say they find nothing. I have numbness and tingling on my left side and my left leg feels heavy and weak. My feet have piercing pain all the time. I don’t know what to do. I have taken pain pills but stopped because it only masks the problem. Help, I am 39 and this has went on too long with no exclamation.

  • Dr Gauresh

    Well if the tingling and numbness is just on the left thigh or rather more pronounced on left thigh then it can be due to entrapment of “lateral cutaneous nerve of the thigh”. This can be ruled out by nerve conduction studies more accurately. Since this is completely unrelated to your low back pain, it would be better to rule out this condition separately.

  • ken

    Hi,I’m ken,21,male,UK. At present ,I have got severe and chronic pain in my left buttock 24/7,which goes all the way down to left foot. I do feel pins and needles,weakness in my foot and leg.I cannot walk straight,cannot stand straight,I could hardly walk for 5mins,because as I walk,then I sweat as pain gets worse.While,I walk,I cannot face straight as my neck faces down due to some reason.2years ago,this pain started as I was working in a heavy lifting job,got physiotherapy for 3 months, then pain went away but not 100%. 4 months ago, got MRI,it shows l5-s1 disc bulge.The part of disc has come out and is compressing the nerve.,got ct guided nerve root injection(anaesthesia and steroid),but didnt effect.
    Shall I get a new MRI, as 4 months ago,when I had mri,then I was walking fine,but now I could hardly walk,as the pain is really severe.I cannot sleep at night as the pain gets worse,when I lie down.Its very hard for me to lie on my back or to lie on my stomach as pain down the left leg makes me restless, so I have to lie side -ways. If i go for a latest mri,then I wonder how would I lie in the mri tube machine as I cannot lie on back or stomach for not more than a minute.Please Help!!!!!!!!!!!

  • bashfaq

    hi….my son is eight years old he doesnt run very fast and climbing down the stairs is a bit tough for him though he swims daily and now started biginners soccer

  • Dr Gauresh

    Well as far as lying down for an MRI is concerned you can be sedated ie. given a drug to make you sleep so that you dont move during the MRI.
    Even I think that you need a repeat MRI, because your symptoms are quite severe. Though you may have severe sciatica too, which produces similar symptoms. Nerve conduction studies should also be done to find out the root of your disease.
    If your existing orthopedist is ignoring your symptoms then consider taking a second opinion.

  • Dr Gauresh

    Well I dont deny the fact that he could be suffering from some thigh muscle weakness. But if he is swimming and playing soccer daily then i guess its not much of concern. Though if he finds difficulty running persistently for a year or so you can consult an orthopedist. Or rather if you feel his disability is significant, do visit an orthopedist. There are several growth disturbances which can be diagnosed early.

  • nadeem

    Hi
    i was in imense pain couldnt sleep sit or stand the doctor and the hospital kept on saying it’s sciatica nerve trapped they gave me pain killers and sent me home. After 2 months being in pain i got a family memeber to massage my back and then tug on my left leg acouple of times which stoped most of the pain, after persisting the doctor to send me for an MRI scan it was revealed that its a slipped disk. Im still waiting for physiotherepy but in the mean time is there anything i can do to stop both my legs and knees feeling weak eventhough the left leg is numb all the time.

  • Dr Gauresh

    If you left leg is numb all the time and a doctor has checked and confirmed it, then ideally you should be going for a spinal decompression or decompression of sciatic nerve surgery. Since neurological impairment like numbness and tingling is progressive and can lead to complete paralysis too.

  • Rueben

    Hello wanted a second opoion because for the last 2 months or more I have been having severe pain in my left leg and both my feet and now the pain is spreading to my right leg also, burning sensations on both thighs and feet hurt soo badly. They did a MRI dn also another nerve test and he says he can not find anything yet I can not walk without a cane up or down a step, this is crazy and im 41 whats next please.

  • Jasangjosh

    Hi,
    I recently experienced right leg weakness for few months now. My leg seem to feel like tiring. I often get back pain after I had my son. I have tried to bed rest but the weakness is more worse. I noticed get in hot shower somewhat help the weakness feeling a little bit. The pain located at my right side of my hip radiates to my calf n down to my ankle. Can you please tell me what I should do at this point ? Thank u for your time ,

  • jphammonds2

    I gave birth 2 months ago, received an epidural. They did have to redo the epidural twice, due to hitting a nerve that caused numbness, pain and my leg jumping up. I’ve now had lower back pain and my legs are feeling weak, w/ coming and going numbness. Sometimes its one leg and sometimes it’s both. I’ve tried massages, stretching, heat compresses, etc and nothing has worked. The pain is awful. What else should I be doing?

  • Dr Gauresh

    If u have weakness and numbness you should consult an orthopedist and get an MRI done to check the status of the nerves.

  • Dr Gauresh

    Consult an orthopedist who can examine you for weakness. Weakness can be subjective in many people, but still its not something one should ignore. An MRI can be helpful to rule out some major diagnoses.

  • Dr Gauresh

    Taking a second opinion is the right decision but I wouldnt be able to comment on the cause as I have not examined you. Burning sensation on thighs can also be due to meralgia paresthetica, which is an affection of the nerve carrying sensations from the skin of the thigh.

  • pjohnsn

    muscle weakness in legs, problems digesting food, back pain, cold. possibly anemic?

    pamj

  • Bijoy das

    Sir,
    My mother is an bone tb patient. Recently her spinal cord was operated. Her legs are so week that she can’t move her leg. Physiotherapy is started. I want to know that how many take time to recover her leg weekess.
    Thanking You.

  • luis

    doc , was at wok all all of a sudden lost sensation in my left leg its happend ones i got relife ,2nd time got relife the ext day ,but it has happen again and takin too long ,it feels like wen walkin i dount feell the ground ,had a spianal fliud test all is good ,ccan u pls help me what to do

  • deep

    i had a sciatica pain for last 12-14 weeks i was feeling that severe pain in my right buttock (24/7) that i was getting problem in walking,now i recovered from pain for last 2 weeks but feeling tiredness in legs and sometimes little pain on right knee cap even after rest or sleep,i am just 21 and i am getting problem in running or doing things of guys of my age

  • btwjmwcpa

    I had weakness in my legs 22 years ago when I was 28. My legs felt weak, and heavy and sluggish. This went away after 8 mos, and just recently reappeared a few months ago. I’m 50 now. Same symptoms, weak and sluggish legs. Walking and running (when I can) seem to make it better, and sitting around just makes it worse. I have had MRI’s of the brain, neck, and lower back. Nothing showed up. Any suggestionsd

  • mounikapolavarapu

    sir
    my mom has disc prolapse problem
    now she is having severe pain in both the limbs especially heels
    it increases with work
    nerve conduction study was done and it showed poor conduction
    she was told its different from disc prolapse
    no need of any medication
    just avoid bending and strainful work
    sir what could b the cause of such severe pain in heels and whole back of the limb apart from disc prolapse
    any impending paralysis?
    kindly give ur advice and also type of exercises like do`s and dont`s
    sensations are normal
    sometimes she feels heaviness of limbs
    she is not a diabetic or hypertensive
    her age is 45 yrs hysterectomy dome 5 yrs back

  • Dr Gauresh

    I think what she has is lumbar canal stenosis where the canal housing the spinal cord becomes narrowed due to overgrowth of inflammatory soft tissues. Keep a watch for any signs of paralysis like as mentioned in the article above. And if problems persist then consult a spine surgeon for surgical decompression of lumbar canal stenosis.

  • Dr Gauresh

    If it is not showing up on MRIs then it must be something related to activity or maybe anemia. Kindly do a full blood workup and consult a physician for ruling out causes of generalized weakness.

  • Dr Gauresh

    At 21 years a common cause of pain in knee cap with the classical symptoms that you have described is due to an abnormal softening of the cartilage of the knee cap called chondromalacia patellae. Do get an x-ray done and maybe consult an orthopedic surgeon for a knee arthroscopy.

  • Dr Gauresh

    I really cannot comment on how much time it will take for recovery since I haven’t seen the patient personally. But approximately it can take from a few months to even a couple of years.

  • Dr Gauresh

    It could be quite serious so kindly try to get an MRI LS spine done at the earliest. Consult an orthopedic surgeon at the earliest.

  • Dr Gauresh

    You could have ankylosing spondylitis, or some other genetically oriented musculoskeletal disease.

  • Nigel Winterbottom

    I am seeking advice about tiredness in my right leg when walking which may be caused by either a spinal (nerve) related problem, peripheral artery disease, or perhaps some other cause I have not considered.

    About two years ago, My wife and I went for a walk and after a few downhill miles we started to return home which was now an uphill journey (not very steep though). I soon had to slow down as my right leg was feeling very tired (my left leg was just fine). There was no pain, numbness or cramping of any kind, it was just as if my whole leg had been involved in a punishing sprint and was just tired out. The tiredness was not localised in any particular area of the leg. At this point, I rested for 5 minutes and the tiredness rapidly dissipated allowing me to resume walking. As I continued walking, the tiredness would return fairly quickly and my leg would again recover after resting for a few minutes.

    I am now 60 years old and have occasionally experienced back pain in the past which can last anywhere between a few days and a few weeks before clearing up on its own. The back pain may occur once or twice per year and usually happens if I have slept awkwardly or have undertaken strenuous activity such as lifting heavy objects or shovelling heavy snow. Generally I have not been particularly concerned about this as many of my contemporaries have experienced this too.

    Since the initial right leg tiredness episode, I have experienced many recurrences. It happens regularly (even on flat surfaces) if I walk either quickly or for too long in a shopping mall for example. On one occasion when I experienced some back pain walking in the mall, the right leg tiredness would occur very quickly (after 20 yards) and I would need to sit down for a minute or two to recover and continue.

    Another thing that I had noticed during the winter months is that after shovelling snow in my driveway during cold temperatures (e.g. -10 to -15C) my feet would become frozen and while this is completely normal, the interesting thing is that upon returning indoors, my right foot would take longer to thaw out compared to my left foot. This unequal thawing time has never happened to me before but it is something I have noticed for the first time this winter season. I should mention that I am not particularly susceptible to cold feet problems unless I am outdoors for a period of time in cold weather. In fact I usually last longer than most other people before my extremeties get cold. My hands and feet are usually very warm and tend to stay warmer for longer compared to most other people.

    This problem with tiredness in my right leg is not noticeable under normal daily circumstances except perhaps when I go up and down a few flights of stairs repeatedly. Also I have not noticed any muscle weakness in the right leg until after it becomes fatigued of course.

    As my Doctor had retired over ten years ago, I have not been able to find a local replacement practitioner who is accepting new patients, although perhaps I should make an effort to do so even if it means travelling to a more distant loacation.

    In the meantime, any advice would be much appreciated.

  • Dr. Chris

    Hi Nigel

    From your account, it does appear that the problem may be related to the blood vessels in the right leg – peripheral arterial disease most likely, but possibly venous insufficiency to some extent as well. The muscle fatigue, colder limb and so on are characteristic of peripheral arterial disease and you should read this article on leg pain while walking. This of course is not uncommon for your age group but needs to be investigated even though it is intermittent. You need to see a doctor immediately. You can read more here on peripheral arterial disease.