Peroneal Nerve Palsy Diagnosis (question)

[Grosso5]

I'm a 33 year old male.  In February, I was seated awkwardly at my computer, stood up and sprained my ankle.  Afterwards, I could not move my foot much, had a limited range of motion, and significant weakness in the foot and toes.  I had a high steppage gait and foot slap.  My doctor recommended a good neurologist.  The neurologist did an exam and asked me specific questions about my seated position.  He said I had a compression injury and diagnosed me with peroneal nerve palsy and said that the foot drop should resolve itself and the strength should gradually return.  I was to see him every couple of months to track progress and to have a nerve conduction test.  After the test a few months later, he explained the results in detail and said they were very typical for a compression injury.  He fully expected me to recover and stated that this was nothing more serious like MS or ALS.
I don't know if I'm at 100% but feel good about the progress I've made.  It's taken 6 months but the foot drop is gone and significant strength has returned to the foot and toes along with the full range of motion.  But, a couple of things trouble me: I've noticed less muscle mass in the leg, specifically in the thighs and buttocks, and experience some twitching all over the leg and "tickling sensations" just below the skin surface.  I have a follow up with the neurologist in a couple of weeks and know you can't diagnose over the Internet and are limited to the information I provide you.  However, I'm very concerned about ALS.  Can you please give me your thoughts?

[LM0SMTH]

I was diagnosed with this same condition for an injury that occurred approximately six weeks ago through a similar mechanism.  My nerve conduction study showed a mild injury of the peroneal nerve.  My neurologist said I would probably recover in fewer than four to six months.  I have had a gradual return of some function and am able to lift all of my toes off the floor and some of my foot upward toward my leg, but only a little bit.  The problem I have is with severe pain.  This ranges from shingles-like pain that is constant, to stabbing, debilitating pain in my big toe, the ball of my toe, and the top of my foot that I feel about 50% of the time.  I have been taking Lyrica 75 mg bid and oxycodone 10/375 1.5 tab q 4 hours prn pain.  

My question is this:  If a mild injury lasts from weeks to three months (approximately), will I continue to feel the pain and require pain medications for this period, as well?  I've been told that sensory and motor injuries to the nerve are atypical and no one has been able to give me a definitive answer.  Is the resolution of this type of pain difficult to predict?

[CCF-Neuro-M.D.-SH]

First of all, keep in mind that I am unable to diagnose you because I am unable to examine you, this forum is for educational purposes.  The symptoms and history that you describe are consistent with compressive injury of the peroneal nerve at the fibular head (the nerve is pressed against the small bone on the outside of your leg just below the knee). These injuries can be mild and only cause conduction block/demyelination (loss of insulation around the wires-making the signals flow slower) or more severe with the loss of "wires".  Mild injuries improve with in a few weeks to 3 months, while more severe injuries will take 6 months or longer.  If you have an injury that involves axonal loss (loss of wires) than atrophy can occur in muscles below the lesion (the tibialis anterior (shin bone muscle)).  From the story you describe, I would not expect thigh/buttock atrophy, unless the compression was higher.  
   ALS is a progressive disease caused by loss of the motor neurons that control muscles.  It can present with foot drop, muscle atrophy and weakness.  However, ALS does not get better. Thus it is very unlikely that your foot drop at least was a manifestation of ALS.  
  I think your risk of ALS is low, but due to the seriousness of ALS, I would make sure you get an extensive EMG (needle exam, not just nerve conductions) to evaluate for ALS and the cause of your atrophy.  I would also recommend an MRI of your spine.  There are also some genetic conditions that can predispose people to pressure palsies such as HNPP (Hereditary Neuropathy with Liability to Pressure Palsies) and can be tested for at the discression of your neurologist.
  I hope this has been helpful.