The operation consists of a mid line incision and then we approach the spine in the gap between the adjacent vertebrae e.g. between L4 and L5. The operation itself involves removing part of the bone (lamina) of the upper vertebra and this then exposes the ligament which is removed. This is a small ligament which runs between the upper and lower vertebrae on each side separately and removal does not weaken the spine in any particular way. Having exposed the nerve which should now be visible a small amount of further ligament and bone is removed so that the nerve can be mobilised to expose the disc protrusion. Sometimes the disc consists of a loose fragment which can then just be simply removed. Sometimes the disc is underneath a ligament which has to be excised and then the disc material is removed in pieces. The disc space is then cleared until there is no loose material and the nerve is free to gentle probing. The wound is then closed in layers.
As with any operation there is a risk of having a general anaesthetic in addition there is a small risk of infection but this is minimised by giving you antibiotics. Blood clots can occur in spinal surgery but are rare and we normally give you elastic support stockings to wear which reduced this to a minimal level. Damage to the nerve that is being decompressed may occur in less than 1%, this could give you either residual leg pain or numbness or weakness usually of the foot which is where this nerve works i.e. a foot drop. There is a serious but very rare chance probably less than 1 in 2000 that the nerve control to the bladder and bowel will be affected causing incontinence of the bladder and bowel. The success rate of this operation is about 75% leaving a possibility that the leg pain would not be improved by the operation but I think one has to look on the positive side.
There is an 80 to 90% probability that your leg pain will be relieved by the operation and usually any back pain is also improved or relieved.
Steroid injections sometimes work but often don’t last and in the end there is no alternative to surgery to unblock the nerve. The longer you leave this the more the chance of some permanent nerve damage done by the disc itself. Sometimes the amount of pressure from the disc has already caused weakness or numbness. This will normally resolve with surgery but if there is significant weakness or numbness prior to surgery there may be some residual symptoms. The nerve then has to recover and this may take weeks or months.
Post Operative Care
After the operation we normally get you up the next day. As I said to you, you may need a catheter inside the bladder if you go into retention and we normally leave this once you are fairly mobile. You will be in hospital several days getting used to walking, sitting and before you leave hospital the physiotherapist will have had you up and down the stairs and once you can do this you will be discharged and need to be seen in 10 days by your practice nurse at the GP surgery for removal of the suture and then a gradual increase of activities up to when we see you usually about six weeks from the operation. You should take any analgesia you need for your back pain during the time that the back is healing. Nerve recovery and leg pain can improve either straight away or gradually over the next few weeks.
You will be encouraged to do regular exercise, going for walks each day and the physiotherapist will give you some exercises while you are in hospital which you should do two or three times a day. Understandably, you should avoid bending, lifting, gardening and heavy house work such as spring cleaning or carrying heavy shopping.