Lumbar Disc Replacement
Why Replace A Disc?
Most joints in the body have been affected by a variety of disease processes and have been treated by fusion in the early days of surgery and more recently by replacing the joint with an artificial one. Whilst the spinal discs are not joints in the technical sense, they do allow a degree of movement which when all discs are taken together confers a considerable degree of flexibility on the spine as a whole.
When a disc is damaged it may lead to pain or abnormal movement, both of which may need correction. Most people get through life with the discs they were born with; in some, however, the discs degenerate, through ageing processes, trauma or repeated stress to the extent that they become increasingly painful. This is typically a central back pain which may spread to the legs in a vague manner, or even into the abdomen.
Standard treatment for this type of pain includes rest during an acute exacerbation, with anti-inflammatory medication, followed by physiotherapy. Blocks, such as epidurals may help. In most instances the pain will resolve adequately, but when it does not the patient may feel that the symptoms are bad enough to warrant surgery.
How Is It Done?
The operation is performed under a general anaesthetic with the patient lying on their back. An incision is made in the left lower quadrant of the abdomen and the muscles are split to allow access. It is unusual for the muscle to be cut at this stage, so recovery of function can be expected.
The spine is approached through the retro-peritoneal space, the peritoneum being the sac containing the bowel, and by moving the blood vessels carefully away towards the right side. The spine can now be seen and the damaged disc can be removed.
The disc prosthesis is a modular design to allow the best possible fit
The disc replacement is inserted after distraction of the disc space (spreading it to restore its normal height) and the wound is then closed. X-rays are used during the operation to make sure the artificial disc is in the right position.
X-rays of three level disc replacement (Prodisc)
X-rays of two level disc replacement (Maverick)
X-ray of two level disc replacement after six years (Charitée) - note bone defect and slip below, which has not changed over this time
Most patients are out of bed with the help of the nursing and physiotherapy staff the day after surgery and out of hospital two to five days later. This will depend upon the home circumstances as well as a variety of other factors,
Exercises commence gently on the first post-operative day. The patient will be taught flexion exercises as extension (of the spine) is to be avoided during the first six weeks after disc replacement. X-rays are taken at six weeks and again at three, six and twelve months after surgery.
Most people are fit to return to gentle activities including non-manual labour, within three to four weeks. Those employed in heavy manual labour should plan to be off work for a minimum of six weeks and may need to consider re-training in a less physically demanding job.
For more information including and animation video of the procedure click here.
What are the risks of this operation?
(note figures vary)
|Nerve injury/paralysis||Damage to the nerve whilst removing disc/bone or inserting the disc||<1|
|Fluid leak||Small tear in the nerve sheath allowing leakage of cerebrospinal fluid||<1 (But higher if previous surgery|
|Infection||Contamination during surgery or, rarely, late infection via the blood||Approx 1|
|Back pain||Some patients will develop back pain due to the stretching of the spine||Transient and dependent upon fitness|
|Bowel injury||Bowel is retracted during surgery||<1|
|Bladder/ureter injury||Structures are retracted during surgery||<1|
|Impotence||Retraction or injury to a small nerve in front of the spine leads to retrograde ejaculation in men||Approx 1 with the retro-peritoneal approach|
|Warm leg||The sympathetic nerve runs alongside the lumbar discs. If damaged the left leg (usually) will feel warmer for some months after the operation||1 - 5 (but higher if previous surgery|
|Wound pain||Surgery||All to some extent|
Back to Surgery