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Michael Barnes - Spine and Orthopaedic Surgeon

Private Service

LUMBAR MICRO DISCECTOMY

Key Points

  • A disc protrusion (disc herniation) occurs when a piece of the intervertebral disc (the soft part between the vertebrae) separates or partially separates and compresses a nerve in the lower spine.
  • Disc protrusion with pressure on a nerve causes sciatica which is pain down the leg in the line of the sciatic nerve and may also cause weakness or numbness.
  • Sciatica often gets better within days or weeks without treatment but sometimes
    persists for months and sometimes never gets better without surgical treatment.
  • Surgery is performed under general anaesthetic and usually takes 30 to 60 minutes.
  • Surgery involves extraction of the disc fragment from under the nerve root through a 3cm to 4cm incision (longer in large patients).
  • Some patients go home the day after surgery, some on the second day.
  • Return to work is variable and may occur in as little as one to two weeks for
    sedentary workers who can get up and walk periodically or may take up to two to
    three months for heavy manual workers.
  • Complications or post operative problems are rare with the exception of recurrent
    disc protrusion which occurs in 2% to 3% of patients in the first year after surgery and 10% at ten years from surgery.


 Frequently Asked Questions

I am still experiencing some sciatica or numbness after my operation. Should I worry about this?
Only a minority of patients experience complete relief of sciatica from the time of the surgery. Most patients notice that it is much improved but there is still some aching in the leg because the nerve has a “memory” for the pain and remains slightly irritable. This usually resolves within a matter of weeks. The numbness usually resolves over weeks or months as the nerve recovers.

If the pain is no better than it was prior to the surgery or is getting worse and worse, please contact the office in case a further MR scan is required to be sure a recurrent disc protrusion has not occurred. 

What do I do with the dressing?
This stitches are under the skin and will dissolve. The dressing is waterproof and you can shower in it. One week after leaving hospital simply peel it off as if it were a big “band aid”. Under the dressing you will find steri strips (tapes) holding the skin edges together. These may come off with the dressing but otherwise remove them one week later if they have not fallen off.

Will I need physiotherapy treatment?
Most patients undergoing a discectomy operation do not have physiotherapy treatment, they simply increase their walking progressively and ease back into normal activity as their symptoms subside over a period of weeks. Some patients, however, prefer to work with a physiotherapist and you should feel free to arrange physiotherapy if that is your preference.


General Information 

A disc protrusion (disc herniation) occurs when a piece of the intervertebral disc (the soft part between the vertebrae) separates or partially separates and compresses a nerve in the lower spine.

A protrusion only occurs at a disc which is beginning to age of wear (degenerate). Disc protrusion occurs at any age from 12 years upwards and is most common in the fourth decade of life (30s).

Disc protrusion with pressure on a nerve causes sciatica which is pain down the leg in the line of the sciatic nerve and may also cause weakness or numbness. Sciatica can be very severe and unresponsive to pain killers and anti-inflammatory medication, even strong pain killers such as Morphine. Sciatica often gets better within days or weeks without treatment but sometimes persists for months and sometimes never gets better without surgical treatment. Improvement in sciatica occurs if the disc fragment dissolves away, gradually shrinks back into the disc or if the nerve stretches over the disc fragment.

Disc protrusion causing sciatica may be treated by surgical removal of the disc fragment if it is not resolving naturally. Micro discectomy operation should be undertaken as an emergency if there is an alteration in bladder or bowel control and semi urgently if there is major muscle weakness.


Surgical Procedure

Surgery is performed under general anaesthetic and usually takes 30 to 60 minutes. It is performed used optical magnification (microsurgery).

Surgery involves extraction of the disc fragment from under the nerve root through a 3cm to 4cm incision (longer in large patients). Any other loose or unstable disc fragments are also removed.

In a small proportion of patients the disc fragment compresses the nerve as it exits the spine rather than in the spinal canal (extra foraminal disc protrusion). In these patients a larger incision is required and the surgery takes a little longer. The image intensifier (mobile X-ray machine) is used to confirm the correct level.


Post Operative Course

Patients stand out of bed and walk to the toilet on the day of surgery.

Some patients go home the day after surgery, some on the second day.

Most patients notice an immediate reduction in the nerve pain down the leg. In some patients all the nerve pain goes immediately but in most patients it is greatly reduced and tails off over three to six weeks.

Some patients are more aware of residual pain in the leg after they leave hospital when the effects of the anaesthetic and pain relieving drugs are wearing off. If the pain in the leg becomes severe please contact the office in case a repeat MR scan is required.

There is discomfort and stiffness at the site of the incision for several weeks, particularly when seated, tailing off over a month or two.

The surgery removes the pressure from the nerve and quite quickly relieves the pain in the leg but numbness or weakness may take weeks or months to resolve and do not always recover completely.

Walking is the only exercise that is necessary when recovering from micro discectomy. Walking is increased progressively, with the aim of walking 1km to 2km outside within two weeks of surgery. Some patients also like to have physiotherapy treatment but this is not necessary for most patients.

Sitting or standing in one position can be uncomfortable for several weeks – simply move about or change position.

You will leave hospital with a waterproof dressing which should be removed one week later. Simply peel off this dressing as if it was a big “band aid”. The stitches under the skin dissolve. No suture removal is necessary.

Return to work is variable and may occur in as little as one to two weeks for sedentary workers who can get up and walk periodically or may take up to two to three months for heavy manual workers.

Driving is normally resumed within one to two weeks when it feels safe and comfortable.


Complications

Complications or post operative problems are rare with the exception of recurrent disc protrusion which occurs in 2% to 3% of patients in the first year after surgery and 10% at ten years from surgery.

Patients who experience a recurrent disc protrusion are not necessarily those who do too much too soon but rather patients whose remaining disc is unstable.

Micro discectomy is undertaken to relieve nerve pain but cannot prevent a further disc fragment from separating (occasionally this occurs within days or weeks of surgery).

A small number of patients experience recurrent or persistent backache due to damage to the remaining disc which occurs when the disc fragment, usually a large fragment, separates from the disc causing sciatica. A very small proportion of these patients have a fusion operation later to address this problem.

Other complications include nerve injury, deep infection or spinal fluid leak requiring further surgery but these almost never occur.

In over 2000 micro discectomy operations one of my patients had a nerve injury which recovered completely, there were two deep infections requiring prolonged antibiotics or surgical treatment and no spinal fluid leaks requiring further surgery.

This page was last updated at 11:31AM on December 17, 2019.