Originally Posted by glenntaj

--for a skin biopsy to test for small-fiber neuropathy to be done only on the upper extremity, as the majority of small-fiber neuropathy cases are length-dependent--that is, the longer nerve fibers in the legs and feet are affected first. Usually, samples are taken from just above the ankle and the mid-thigh, and also sometimes from the back of the elbow and the gradients compared. If there is also NOT a length-dependent gradient, that also has implications for diagnosis. But the comparisons should be done, as it is possible to have "local", non-systemic nerve damage/axon loss, often from injury, and that would likely show on a skin biopsy as damage to one area but not another. For instance, axon loss in the upper arm, but not in the thigh or calf, would be consistent with nerve injury to the brachial plexus or the cervical spine roots, and in the latter case most likely caused by either acute disc injury or more chronic neural formainal narrowing due to disc herniation/osteophytic bone spur overgrowth.

And, there's also the RSD history to complicate matters.

It would be wonderful if you could post the language used in the imaging reports--we do have people here well versed in that who could provide perspective.

Originally Posted by mrsD

Hi Catra...

I've been searching the connection between CRPS and SFN, and there seems to be one:

Skin biopsy in complex regional pain syndrome: case series and literature review. - PubMed - NCBI

and
Complex regional pain syndrome - Diagnostic workup

So I guess a question to your new neuro would be if your biopsy is a separate issue or connected to your RSD/CRPS.

Originally Posted by catra121

Thanks for reading and any insight or suggestions would be greatly appreciated.

Originally Posted by dogwalker

My response is in regards to meds (which I realize you want to get off of). However, I've used amitriptyline for both CRPS and SFN and wonder if you've tried it at any point? I had SFN in my feet for a year starting in 2005; then the following year developed CRPS resulting from thumb surgery. (Fortunately I recovered from that in 9 months with lots of hand therapy). For the CRPS I took 75 mg. amitriptyline divided through the day, and for the SFN which has returned, I take a single dose of 60 mg. before bed time. The only significant side effect has been dry mouth. It definitely helped with the CRPS pain. I don't think it helps with my SFN pain, but my pain is mainly at night and the amitriptyline does help me get to sleep and stay asleep. This and medical marijuana have allowed me to avoid having to try any other meds which I fear would have worse side effects. Good luck with finding answers and relief.