INDICATIONS: Severe sciatica (pain radiating down the back or side of the leg) or severe femoratica (pain down the front of the thigh) that has persisted despite six or more weeks of conservative management (see non-surgical care) which may include drugs for pain or inflammation, physiotherapy, manipulation or epidural steroid injection. When the pain is getting better it is appropriate to wait longer. When there is severe weakness surgery is considered sooner and any problem with passing urine should be reviewed urgently.
PROCEDURE: After appropriate medication the patient is taken to the operating room where he or she is anaesthetised (full general anaesthetic with a tube into the trachea). The patient is rolled onto their front and placed on a sheep skin lined frame which allows the tummy to hang free (this relieves pressure in the veins in the spine - epidural veins- and reduces bleeding). The elbows are flexed and lie on pillows while the face sits in a specially cushioned mask.
Local anaesthetic (for post-op pain relief) is injected into the skin of the back before making a cut about 4-6cm (1-2 inches) long. This may be longer if more than one level is being done or if the skin is fat. The muscles are lifted from the spines gaining access to the space between the vertebrae usually on one side only. Part of the ligament between the vertebrae (ligamentum flavum) is removed (about 1 x 1.5cm) allowing access to the spinal canal where the nerves lie surrounded by a layer of fat containing veins. The nerve that is being compressed is lifted towards the midline and held lightly with a retractor. This reveals the prolapsed or bulging disc and any free pieces (sequestrated) are removed. A probe or scalpel is used to make an entry into the disc bulge revealing usually a mass of firm tissue (like crayfish)about the size of a pea which is removed. Special forceps are used to remove any other loose pieces within the disc and the space is washed with fluid again to remove any loose bits.
The only hole made into the disc is usually the hole out of which material has come and the remainder of the strong outer fibres of the disc remain intact. Nothing is placed into the disc and it is not possible to sew the disc up. Sometimes it is necessary to trim the adjacent bone, an operation called a laminectomy, or to trim the facet joint (facetectomy) in order to completely free the nerve.
At conclusion, a small piece of fat may be placed around the nerve to reduce scarring, the overlying muscle is stitched back before closing the skin with a single long 'invisible' stitch which does not need removal.
COMPLICATIONS see separate entry
Specific complications of discectomy include operating at the wrong site (very rare), injury to the nerve (usually just a superficial tear in the lining of the nerve which can be repaired but means you have to be flat in bed for two days afterwards) and a risk that the prolapse can occur again. This risk exists whether you have an operation or not.
Scarring can occur around the nerve but this is less when the surgeon is experienced, uses a delicate technique and uses magnification (I use 4.5x magnifying loupes).
Paralysis does not occur with this operation as the spinal cord ends at the upper lumbar level well away from the usual site of operation.
POST OPERATIVE INSTRUCTIONS: You will be discharged home after one or two nights (usually one). You will have tape on your wound which you should take off after five days. If you are worried about the wound - soreness or redness -speak to me or your GP.
I encourage you to walk initially five to ten minutes twice a day increasing over the first four weeks to 30 to 60 minutes twice a day.
You will be shown an exercise to keep your nerve mobile. This is done lying on your back, lifting your thigh up to a right angle and then straightening the knee until it gets tight. Hold for fifteen seconds, relax then repeat ten times. Do this with each leg, one at a time, three times a day. It is not usually necessary to have physiotherapy.
After a month I will see you or talk to you over the phone if you live far away. Mrs Howie will discuss exercises with you before discharge from hospital and again two weeks postop.
Please ring on the day of discharge for appointments.
You will usually be able to start swimming or exercycling after one month.
I advise against driving for one month - this is more for the protection of others and potential insurance problems.