At some point in life, 80 per cent of all adults will suffer back pain - and mostly in the lumbar region. The lumbar vertebrae lie near the base of the spine and are the major supports of the body's weight. They are also the site of the lumbar plexus, a network of nerves supplying the muscles of the lower trunk, legs, groin and genitalia.
Between each spinal vertebra is a shock-absorbing disc that is hard on the outside, but soft in the middle. When the jelly-like interior is squeezed out of the disc through injury or wear and tear - variously known as a 'slipped disc', 'prolapsed disc' or 'herniated disc' - the resultant back pain needs attention.
Lumbar surgery is used to treat this and a variety of other lower-back complaints, including a pinched nerve (spinal stenosis), sciatica or a fracture. The most common operations are:
* laminotomy: part or all of the lamina (arch formed over the back of the spinal cord) is removed to relieve pressure on the cord, or to access a bony spur or damaged disc
* discectomy: removal of the part of a disk that is pressing on a nerve and causing pain
* fusion: two vertebrae are joined together by bone grafts, sometimes with metal plates, to stabilise the spine.
Is it safe?
No. Lumbar surgery should only be a last resort as there are safer methods of pain relief without surgical intervention.
* There's a small risk of dying from deep vein thrombosis (DVT), a bloodclot in the lungs, heart attack, blood transfusion, pneumonia or other infections, respiratory depression and kidney failure (BMJ, 2000; 321: 1493).
* Even if you don't die, you can still develop DVT, or bloodclots in your legs, pelvis or abdomen - which can then cause death when the clots are circulated to the lungs or brain.
* You could develop complications that are seemingly unrelated to the lower back. The most common major complications affect the lungs; the most common minor complications affect the nerves of the genital and bladder regions (J Bone Joint Surg, 1996; 78: 839-47).
* There's an overall 1-2 per cent risk of nerve damage (BMJ, 2002; 324: 1414).
* You also risk paralysis, muscle weakness and loss of bowel or bladder control (Medline Plus; www.nlm.nih.gov/medlineplus/ency/article/002973.htm).
* According to Spine Health 2004, the North American Spine Society's latest campaign, spinal fusion to correct lower-back pain has a strong likelihood of failure. At best, you've got a one in five chances that your pain will persist.
* There's a 2-15 per cent risk of accidental puncture of the dura mater (one of the protective layers of the spinal cord), which will require surgical repair (Acta Orthop Scand [Suppl], 1972; l42: 1-95).
These are on top of the usual risks of any operation, including reactions to the anaesthesia, and bleeding and wound infection.
What doctors don't tell you
* Only 30-40 per cent of back surgery is considered successful, even using the most liberal criteria (J Bone Joint Surg, 1997; 6lA: 20l-7; Spine, 1984; 9: 6l4-23).
* As much as 40 per cent of patients fail to achieve satisfactory long-term relief after surgery, and 66 per cent fail to achieve relief after repeated operations - the so-called 'failed back-surgery syndrome' (Neurosurgery, 1991; 28: 692-9).
* Nearly three-fourths of patients who undergo back surgery still complain of back pain. In addition, 23 per cent complain of constant pain, and 35 per cent still require treatment (Spine, 1988; l3: l4l8-22).
* Surgery doesn't improve quality of life. Most patients report no change in their ability to work or perform activities such as walking, climbing stairs, driving and sleeping, or in analgesic use. Patients felt that neurological functions such as strength, sensation, bowel or bladder control were worsened more than improved by surgery (Neurosurgery, 1991; 28: 685-9l).
* GPs are largely unaware of how to manage lower-back problems, in spite of clinical guidelines laid down by the Royal College of General Practitioners. They also tend not to recognise the warning symptoms, and fail to appreciate the benefits of manipulation techniques (such as osteopathy) for persistent symptoms (BMJ, 1996; 312: 485-8).
* Surgery is probably unnecessary. A large number of patients told they needed surgery were able to avoid it in the short term simply by doing aggressive back-strengthening exercises (Arch Phys Med Rehabil, 1999; 80: 20).
* If offered within the first six weeks of an episode of low-back pain, manipulation techniques provide better short-term improvement in pain and activity levels than conventional treatments, with minimal risk, provided patients are assessed properly by a trained practitioner (BMJ, 1999; 318: 261).
* Multidisciplinary biopsychosocial rehabilitation can produce significant improvements in pain and function in those with disabling chronic low back pain (BMJ, 2001; 322: 1511-6).