I had a very small amount of disc material removed from the L3-4 area of my lumbar spine. I ended up with more scar tissue than disc. My symptoms are worse now than they ever were before the operation. Does this happen very often? And why does the body make so much scar tissue?

Removing a disc or disc fragment is called discectomy. It is indicated in patients with persistent back and/or leg pain. The operation can be done with a very small incision and the aid of special surgical tools and instruments.

The hope is for a significant reduction in pain after the operation. But in a fair number of patients, pain is not improved. In fact, as in your case, the symptoms can be much worse. In 24 per cent of all cases, peridural fibrosis is the reason for failed-back surgery syndrome.

Peridural fibrosis is the formation of scar tissue in the area where the disc was removed. Scientists aren’t sure why scar tissue (and especially so much scar tissue) forms during the acute healing phase.

It could be the body reacts to intraoperative debris as if it were a foreign object. Or the pH (acid/base) levels inside the tissue may set off a series of tissue interactions. The result is an excess amount of scarring (also known as fibrosis).

Some experts have suggested that damage to the spinal muscles during the operation is a key factor. Fibroblasts from the surface of the muscles move to the open area where the disc was removed. And any type of hematoma (collection of blood) in the area can also start the process of scar tissue formation.