When an intervertebral disc becomes displaced into the area of the spinal canal, this is often called a slipped disc, herniated disc or sometimes an extruded disc (see the herniated disc section). When non-operative means have failed, surgery is sometimes recommended. In most cases the surgical goal is to remove only the fragment or portion of the disc which is causing nerve disc is left in place and only a portion is actually removed. The success rate of such surgery (usually called microdiscectomy) is very high in reducing or eliminating pain and dysfunction.

Complications related to disc removal can arise even in the very best of hands. Some of the more common things that can cause trouble after disc removal surgery include:

1. Persistent nerve irritation and leg pain
This can occur when a large disc herniation was present and the nerve, although freed from the surgery, has not had time to recover yet or has had some element of permanent nerve damage. Another possibility is that insufficient disc material was removed and therefore continued nerve irritation is present. Other possible explanations include infection, improper diagnosis, nerve injury at the time of surgery…

2. Initial improvement but then return of leg pain
This may occur if after the nerve was freed in surgery, another piece of disc material pushed into the spinal canal (recurrent disc herniation). Unfortunately, this is not so uncommon (up to 20%) and a second surgical procedure may be necessary to decompress (free up) the nerves again. Other possible explanations for return of nerve irritation and pain, include: disc collapse with nerve compression, infection, spinal instability, abundant scar formation around the nerve (this can entrap the nerves and cause pain/dysfunction).

3. Improved leg pain but increasing back pain
If the nerves have been successfully freed during surgery yet the spine has been destabilized (the structure is weakened), then the spine may not have sufficient stability to function normally with everyday activities (spinal instability). Consequently, pain may develop and muscle cramps or spasms in the back can occur. Other explanations for increasing back pain after surgery include: infection, disc collapse, injury to the facet joints (small joints behind the spinal canal), abundant scar tissue, improper diagnosis…

Learn more about Revision Surgery in our Revision Surgery Tutorial.