Lumbar Decompression & Discectomy Surgery
What are lumbar decompression and lumbar discectomy surgery?
Both procedures are operations to relieve pressure on the spinal nerves in the lower back. The lumbar nerves supply messages to your back and legs and when they are compromised, can cause debilitating pain.
It is often used to treat spinal stenosis (narrow spinal canal), a disc bulge (a protruded disc compresses the nerve root), a disc prolapse (a ruptured disc leaks a gel-like substance and compresses the nerve root), spinal tumours and spinal injury.
In general terms a discectomy operation is to remove the part of the disc that is producing the nerve pain down the leg. A decompression' is to remove bone or soft tissue compressing the contents of the spinal canal. In some patients a combination of the two procedures may be required.
Why is this surgery suitable for me?
Lumbar surgery is recommended when the pain in your back and legs is affecting your quality of life and alternative treatments, such as pain relief and physiotherapy, have not worked. If you have previously had a series of spinal injections and these have not provided long-term benefit, this indicates that definitive long-term treatment such as surgery may be required. The main aim of surgery is to relieve the pressure on the nerve. This will mean that there is a good chance that the pain in your leg will go or at least be much improved.
How is it performed?
If the surgeon performs a discectomy a small incision is made into the lower back. The disc bulge or gel-like disc material that is compressing the nerve is removed. There is no need to remove the whole disc, just the part that is bulging.
If the surgeon performs an open decompression the incision will be longer and more muscle is stripped. A small portion of the bone over the nerve root and/or disc material from under the nerve root is removed; this gives the nerve more space to heal. Post operation you should benefit from some immediate relief. Some residual leg pain, numbness or weakness may persist for several weeks until the nerve has rejuvenated.
Both procedures are performed under general anaesthetic. You will need a minimum one night stay in hospital.
Some important considerations
If you have had pressure on the nerve for a long time or the nerve has become damaged by the pressure, you may not get a complete recovery of the nerve function. This means that you might always have some numbness in parts of the leg or arm, or weakness of some of the muscles after surgery.
Surgery seems to get people better quicker but has some risks associated with it.
Certain types of disc prolapse are more likely to recur than others. Surgery for disc prolapse has a recurrence rate of between 7% and 15% within ten years. This is the same whether or not you have an operation.
Surgery seems best when severe or quite bothersome symptoms have not settled to the patient's satisfaction and have lasted more than 6-8 weeks.
Surgery has less risk and is safer on fit and healthy patients. It is common sense to take responsibility as a patient to reduce the risks whenever possible. Simple measures such as stopping smoking, losing weight and improving aerobic fitness all help.
Patients who are diabetic have a slightly increased risk of infection generally and the nerves in diabetic patients may not recover as well as others.
70-75% of patients experience a significant improvement in leg pain
20-25% may be better but still have persistent leg pain
5% may have no benefit at all
1% may be worse in terms of pain
Superficial wound infections are not rare and may occur in between 2% and 4% of spinal operations.
Deep spinal infections are much more serious but less common. A deep spinal infection occurs in less than 1% of cases. To reduce the risks of infection antibiotics are often given and the surgery is performed in strict sterile theatre conditions. If a deep infection occurs it may require repeat operations to washout the spine and a prolonged and extensive course of antibiotics.
This is where an opening occurs in the dura, which is the lining of the spinal canal. The spinal fluid within the spinal canal will drain out of the hole. This occurs in about 8% of cases. Sometimes the hole can be repaired with stitches or a patch. Usually the leak of fluid dries up within a few days and there is no long term effect.
Damage to spinal nerves
The spinal nerve causing the pain may be already damaged by the disease process. The disc prolapse can cause scarring within the nerve such that it is unable to recover despite technically successful surgery. Sometimes the nerve can be stretched in trying to remove the disc lying under the nerve.
The risk of paralysis, which means loss of use of the legs, loss of sensation and loss of control of bowels and bladder is low (<1%). Paralysis can occur as a result of damage to the blood supply of the nerves or spinal cord, and this is not reversible.
The risk of death is low, and occurs at an incidence of <1%.