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Leg Numbness Near the Knee

    • 4 posts
    October 27, 2014 12:07:10 AM PDT
    I have a spot just above and to the right of my left knee. I haven't injured myself that I'm aware of but I am taking antibiotics (cephalexin) for an abscessed tooth. I also got a shot of the same in both buttocks over a week ago. The spot has been numb for several days, maybe even a week and is painful at times. My foot is also tingling.
    • Moderator
    • 1955 posts
    October 27, 2014 12:43:42 AM PDT

    Greetings C, 


    Thank you for the question. 

    If the photo is that of yoruself. Please change it to a photo that you find interesting. A favorite building, city, animal, etc. This a public website seen around the world. 


    Legal disclaimer:  we do not have a doctor-patient relationship and we cannot give specific instructions of care to you, but we can give you our best effort to find high-quality information that you can consider. If we are wrong, or you don't like what we say, feel free to leave a message and let us know how we can improve the quality of the service. In addition, we encourage other people in the community to contribute their knowledge to the questions that are asked. 

    For example, if you have a rare disease, and had a rare surgery, please simply state "back surgery," and if needed we can explore that further.  If your neighbor or best friend reads this, will be they be able to identify you based on the information given? If yes, please remove the information or change it slightly. 

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    Acceptable example: I live in the United States, I had a tumor & surgery, then I traveled abroad for work.


    1. Please change the picture if that is yourself for privacy.


    1. What is your question(s)?

    2. Age & gender, Please add or substract (1-3years if adult for privacy)?

    3. When did problem start?

    4. Have you had this before? 

    5. Is it getting better or worse? 

    6. Body Mass Index?

    8. Heart Rate? 

    9. Temperature? 

    10. Medical conditions, both past & present?

    11. Medications & supplements?

    12. Surgeries? 

    13. Why did you receive the shot of Cephalexin in both buttocks over a week ago. 

    14. Please measure the spot with a rule (centimeters preferred).

    15. Please note the color. Again this is a public website, you are welcome to upload a photo of your knee lesion, but if you choose to do so, it will seen aroudn the world, so I would prefer that you describe 

    16. color, 

    17. size

    18. border (round, square, 

    19. Ever had skin lesion like this before?

    20. Is the skin intact? 


    After you answer the above I will have more questions. 

    Kind regards,


    • 4 posts
    October 27, 2014 1:41:03 AM PDT
    What could be causing the numbness and is there anything that could help it stop? I am a female, 30 years old. The numbness started about a week ago and it has never happened before. It isn't getting better as my hands, feet and ankles are now also swelling. My bmi is 33, my heart rate is normal, temp is 98.9. I've had gall stones, 2 pregnancies c section with both and my gall bladder removed. Currently, I have arthritis and an abscessed tooth. The infected tooth is the reason I got the antibiotic shots. The region that is numb looks normal like my leg and knee always look. There is no visible injury or lesion so I can't measure it.
    • Moderator
    • 1955 posts
    October 27, 2014 2:13:06 AM PDT

    Thank you for the update C,


    Is the numbness isolated to only the left leg? 


    Please have a look at the video and let me know if the pain you are experiencing is consistent wtih the video. In what ways?


    1. Have you noticed a change in your urine recently, color, amount of urine?

    2. How long after the injection did you begin to have numbness in the leg?

    3. Do you have swelling in the leg?

    4. If you have swelling in multiple extremities you should go to the hospital.

    (when did the swelling in the extremities start? Is this the first time you have had the Cephalexin before?)

    5. Do you have difficulty breathing, shortness of breath, nausea, vomiting, diarrhea, constipation?

    6. Do you have a change in the color or consistency of your skin of your knee?


    7. can you bend your feet up and down with normal strength?

    8. Please take a look at the photo below and let me know if you have pain localized to about any one (or more than one) of the regions. you may not).

    9. Please let me know if you have developed a rash or hives, or itching, or burning of the skin.


    I look forward to hearing form you. 

    Kind regards,


    Leg pain

    Pain Questions:
    1. Location of pain, (can you point a finger to it, or is it larger)?
    2. Intensity, (How intense is the pain on a scale of zero-to-10 (0 is no pain, 10 is the worst pain)? 
    3. Quality, (sharp or dull)?
    4. Onset, (when did you first have the pain)?
    5. Duration, (How long do painful episodes last)?
    6. Radiation, (does the pain spread anywhere)?
    7. Associated, (What else has been associated with the pain; is there anything that started when the pain started)?
    8. Alleviating factors, (What has made the pain better)?
    9. Aggravating factors. (What has made it worse)
    10. How much pain are you in after treatment with your current medication(s) if any?
    11. How much pain are you in without treatment?
    12. How has the pain affected your quality of life (if chronic pain)? 


    • Moderator
    • 1955 posts
    October 27, 2014 2:20:33 AM PDT

    This is a list of adverse reactions to the medicine Cephalexin per Lexicomp 


    14. When did you develop the arthritis

    15. What joints are affected with the arthritis, THe knees, the hands or where?

    16. What type of arthritis do you have (have you been told you have a certain type of arthritis)

    17. Do you know why you have an abscess in your mouth? Did you have a cavity that progressed, do you have diabetes?

    15. Sudden swelling in multiple extremities... warrants a visit to the emergency room. It is possible that you could be having a reaction to the medicine and/or losing protein in your urine?


    Cephalexin Drug Information:


    Adverse Reactions Significant 

    Frequency not defined.

    Central nervous system: Agitation, confusion, dizziness, fatigue, hallucination, headache

    Dermatologic: Erythema multiforme (rare), genital pruritus, skin rash, Stevens-Johnson syndrome (rare), toxic epidermal necrolysis (rare), urticaria

    Gastrointestinal: Abdominal pain, diarrhea, dyspepsia, gastritis, nausea (rare), pseudomembranous colitis, vomiting (rare)

    Genitourinary: Genital candidiasis, vaginal discharge, vaginitis

    Hematologic & oncologic: Eosinophilia, hemolytic anemia, neutropenia, thrombocytopenia

    Hepatic: Cholestatic jaundice (rare), hepatitis (transient, rare), increased serum ALT, increased serum AST

    Hypersensitivity: Anaphylaxis, angioedema, hypersensitivity reaction

    Neuromuscular & skeletal: Arthralgia, arthritis, arthropathy

    Renal: Interstitial nephritis (rare)


    Hypersensitivity to cephalexin, any component of the formulation, or other cephalosporins


    Concerns related to adverse effects:

    • Elevated INR: May be associated with increased INR, especially in nutritionally-deficient patients, prolonged treatment, hepatic or renal disease.

    • Penicillin allergy: Use with caution in patients with a history of penicillin allergy, especially IgE-mediated reactions (eg, anaphylaxis, angioedema, urticaria).

    • Superinfection: Prolonged use may result in fungal or bacterial superinfection, including C. difficile-associated diarrhea (CDAD) and pseudomembranous colitis; CDAD has been observed >2 months postantibiotic treatment.

    Disease-related concerns:

    • Renal impairment: Use with caution in patients with renal impairment; modify dosage in severe impairment.

    UpToDate Cephalexin

    • Moderator
    • 1955 posts
    October 27, 2014 3:00:07 AM PDT

    Hello C, 


    If* you have weakness or altered sensation in one of the lower extremities after injection into the buttock, it is possible that there could be nerve injury, possibly to the "sciatic nerve."

    If this is the case, you probably want to be evaluated in order to prevent permanent loss of function. The reason is that if a nerve is damaged, it is possible that you could permanently lose some or all of the muscle function of the muscles supplied by that nerve.


    The following types of function can be affected by damage to the sciatic nerve during intragluteal injection.


    1. motor (cant move as well)


    2. sensory


    3. sweating


    In addition, I would argue that the evidence suggesting you visit the emergency is also supported by the swelling in your extremities. 

    Please consider keeping me updated.

    Best regards,




    Combes MA, Clark W, Gregory CF, James JA. SCIATIC NERVE INJURY IN INFANTS: RECOGNITION AND PREVENTION OF IMPARTMENT RESULTING FROM INTRAGLUTEAL INJECTIONS. JAMA.1960;173(12):1336-1339. doi:10.1001/jama.1960.03020300048015. 

    • 4 posts
    October 27, 2014 9:51:53 PM PDT
    Yes the numbness is in my left leg only but both feet are also tingle like they have fallen asleep. I also forgot to mention there's a pain in my right buttock and it is very tender also it itches constantly but there is nothing visible on the skin.
    There is some pain in my lower back and in my leg but not too similar to the video. I have been urinating more frequently but no other changes in urine.
    The numbness started a day or two after imperfection. My leg isn't swollen but my ankles are and that began a day or two ago.
    I have taken Cephalexin many times as I am allergic to penecillin. I have no difficulty breathing etc. There's no noticeable changes to the skin. Yes I can bend my feet normally. As for the picture the numbness/ pain is in the medial and intermediate cutaneous of thigh L2,3. More specifically if I place my fingertips on the bottom of my knee it stretches from my fingertips to the wrist and inward to the bend in my knee but not behind it.

    Intensity: generally about a 6 but higher at times
    quality: dull; occasionally sharp stabbing pains
    Onset: a week
    Duration: constant dull pain, sharp pains last a few seconds
    radiation: radiates down leg
    Associated: pain in buttock, swelling in hands and feet, i had to lubricate my rings to remove them, lower back pain
    Alleviating factors: none so far
    aggravating factors: standing and walking for any length of time
    With meds (advil and tramadol (for the abscess))
    The pain is less than excruciating but only for short periods of time.
    • Moderator
    • 1955 posts
    October 28, 2014 2:53:42 AM PDT

    Thank you for the update C,


    1. Are you able to go to see your physician regarding the swelling today. Say either the primary care doctor. You have swelling of your ankles, and possibly of your hands. Along with the pain. 


    1. Swelling of Ankles - Has this happened before, if not, please see a doctor. 

    2. Swelling of hands

    3. Tingling sensation in both feet - could be related to swelling, could be related to a neuropathy . 

    4. Pain in the right butock that extends down the right leg (possibly sciatica).

    5. Dental Abscess (on cephalexin): This should be getting better, is it? Before the cephalexin you did not have the above or below problems, except for that of arthritis. 

     -- Did you have an incision of the abscess?

    6. . Pain in the left knee (l2, l3 anterio cutaneomedial nerve of the thigh) - specifically focused around the anterior part of the knee. 

    7. Arthritis - 



    1,2. Edema: investiated in ER or doctors office. 

    3. Tingling in the feet. Check for diabetic neuropathy, and other types of neurological diseases, check reflexes.

    4. Sciatica: discuss possibility of nerve injury during injection with your doctor, see what they say.

    5. Follow-up on dental abscess.

    6. Left knee pain: have exame by a doctor.

    7. Arthritis: ask your doctor what type of arthritis you have. 

    Please consider seeing a physician soon as I am concerned that it could be a sign of additional problems. for example, Kidney disease from the medicine. (it is not reported frequently, but kidney failure has been reported after use of Cephalexin.

    Please consider keeping me updated.

    Kind regards,


    This post was edited by Brett Snodgrass at October 28, 2014 2:54:03 AM PDT
    • 4 posts
    October 28, 2014 9:56:14 PM PDT
    I went to the ER and I the diagnosis I received was completely ridiculous. The Dr said I had a sprained ankle. I assure you, I do not. There is nothing wrong with my ankle other than it is swollen. To answer your questions yes I've had swollen feet and ankles before but never without cause such as standing or walking for several hours. My hands have swollen before as well, but not often. The tingling sensation I've also never had unless my foot was asleep.
    The dental access has pretty much healed and yes it had to be cut so it would drain.
    The arthritis is the only problem I had before the Cephalexin. I was told it was osteoarthritis.
    While in the ER the Dr did an ultrasound on my leg to rule out a blood clot. He also pressed on the back of my knee and calf and both were very painful. He also had said it might be a Baker cyst. I will definitely be getting a second opinion bc he is the same Dr that told my mother that she was suffering from muscle pain when actually the stints in her legs had collapsed and she had to have a femoral bypass a week later. Im not a Dr but I know that I don't have a sprained ankle, I can walk just fine the pain radiated down from the knee.
    • Moderator
    • 1955 posts
    October 29, 2014 3:08:27 AM PDT

    Greetings C,


    Thank you for the update. 


    Did the doctor do anything do evaluate your swelling. From what we have discussed you had that in both legs. (feet, and the hands). 


    1. Do you have a primary care doctor? Have you been evaluated for diabetes?

    2. Has the numbness in your feet come closer to your body? or become more severe?

    3. Have you had any weaknes.s 

    4. Did the doctor collect urine? I thought it may be reasonable to evalute the urine to make sure that the swelling wasn't due to protien loss. 

    5. I am very glad that the abscess has healed. 


    6. I thought both of your ankles had numbness and tingling, and that your right foot had sciatica. 

    7. You should purposely ask the doctor for a urine diplstick - analysis. be sure to mention that you had the injections into both buttocks.




    8. How is the tingingling in your feet? Better or worse
    9. How is your left knee numbness 

    10.Is the pain in your right leg worse or better?

    11 Is the swelling better or worse?

    12. Please setup an appointment with your primary care physician, or an acute care clinic. Either way, you should be evaluated iwth a test using a urine dipstick to check for protien in the urine. 

    13. There are several other websites such as sharecare, healthtap, that have many excellent resources. I would encourage you to visit the automated question-answer may be helpful. 


    Please consider keeping me updated.