What is the best treatment for "severe" sciatica pain. my last resort for my mother is neuromuscular release technique with poss. nerve block.

Surgery : If sciatica is severe and unresponsive to pt or steroids/nerve blocks, surgery may be required to release the compression from a disk herniation or bone spur.

Depends: The best treatment depends on the cause of the sciatica. Until that is known there is no best treatment. If it is from a herniated disc then physical therapy, exercise and anti inflammatory medication is a good start. If it does not improve i would consider an epidural injection within 3 months of the pain onset.

Spine Pain Options: This chronic pain in the distribution as you suggested is the result of an irritated nerve or facet joints or other injury typically in the lumbar spine (low back) which are caused by herniated disks, spinal stenosis or degenerative disc disease, etc requiring further evaluation by a spine specialist and may be candidate for facet injections/radiofrequency ablation and epidural steroid injection.