I am a long-standing back pain sufferer. MRI scans have shown a disc prolapsed between the second and third vertebrae, but not bad enough to risk an operation. I am now 40, and the pain in my spine seems to have alleviated a little but I now get particularly severe pain in my hips and sacroiliac joints. What might this be and what can be done about it?
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Low back pain is a common ailment: 80% of the population will experience it at some time during their life, 50% of whom will consult their GP, 15% will visit hospital, and about 1% will experience enough pain and discomfort to warrant surgery. Incomplete functional recovery often occurs after an acute bout of low back pain, depending on the severity of the original episode, the presence of degeneration between the vertebrae, whether trauma is involved, whether a muscle imbalance is present, and a host of imponderable factors.

However, not all back pain results from local problems. In your specific case, the association of back pain with hip and sacroiliac joint pain (at the bottom of the spine) may well suggest ankylosing spondylitis as the underlying cause of your symptoms. This is a chronic, progressive inflammatory arthritis, primarily affecting the spine and the sacroiliac joints, but encompassing the hips as well. Eventually, it may induce fusion and complete rigidity of the spine, a condition known as bamboo spine. More men than women are affected, and management is normally through physiotherapy and medication.

Ankylosing spondylitis allows high levels of physical activity: for example, former England cricket captain Mike Atherton was affected, and played on for years. In the first instance, the best specialist to consult would be a rheum-atologist. The diagnosis is normally made by examination and x-ray. The condition may be associated with the HLAB27 gene, detected in a blood test.

Physical therapy, exercise, stretching and appropriate medications form the basis of its treatment. Advocates of alternative medicine suggest special diets such as a starch-free diet or the paleolithic diet, but it is important to confirm the diagnosis before embarking on any therapeutic adventure.

· Professor Maffulli is a consultant orthopaedic and sports injury surgeon at Keele University medical school. If you have a question for him, email fitness@theguardian.com