Physiotherapy in North America for Lower Back

Q: I had a microdiscectomy for a herniated disc at L45 about 10 months ago. The back pain is fine but the leg pain has come back. If the disc is gone, why am I having leg pain again?

A: Over 200,000 discectomies are performed every year in the United States. Discectomy refers to removal of the disc, which is a cushion and shock absorber between two vertebral (spinal) bones.

Depending on how things look in the spine, the surgeon may remove part or all of the disc. The procedure can be done with minimally invasive techniques so that only a small incision is made with minimal disruption to the surrounding tissues.

The surgeon may use a minimally invasive method such as microdiscectomy. A small incision is made and the damaged portion of the disc is removed. A microscope helps magnify the disc so the surgeon can see the area clearly.

Another surgical technique is the endoscopic discectomy. This is another minimally invasive procedure. The surgeon uses an endoscope, which is a tube through which instruments can be passed to remove the damaged portions of the disc. The surgeon can see on a video screen as the disc is removed.

Sometimes surgeons combine parts of both procedures to perform what's called a hybridization of techniques. The goal is to avoid bleeding and soft tissue damage while removing the offending disc. The hope is to reduce hospital time, use of narcotic (pain) medications, and get the patient back to work as soon as possible.

Painful symptoms can come back when a partial discectomy (rather than complete removal of the disc) is done. Forces applied to the remaining disc exert the same pressure that eventually push it out of the disc space. Pressure on the nearby spinal nerve root from the protruding disc or chemicals released by the damaged disc can irritate the nerve causing back and/or leg pain.

If the pain is not being caused by a recurrent disc herniation, it could be coming from a different disc (possibly the level above or below the disc in question). There are other potential causes for leg pain after a discectomy. An examination and evaluation by the surgeon is needed to make a clear diagnosis.

Simple X-rays don't show discs but they can help rule out other possible causes of back pain and sciatica such as fractures, spinal instability, or stenosis (narrowing of the spinal canal).

MRIs help show the difference between abscess, scar tissue, hematoma (pocket of blood), and disc herniation. Lab testing of blood also helps the surgeon tell if the new pain might be coming from infection.

Reference: Joseph K. Lee, MD, et al. Recurrent Lumbar Disk Herniation. In Journal of the American Academy of Orthopaedic Surgeons. June 2010. Vol. 18. No. 6. Pp. 327-337.