The spine has 2 main functions
- It is the flexible central part of the skeleton, keeping you upright and allowing a variety of postures
- It is a conduit for the nervous system as it travels from the brain to the rest of the body
Disorders of the spine present with symptoms related to these 2 functions. Problems with the joints, ligaments, bones and muscles may present with spinal pain. Conditions that impinge on the nerves may present with pain in the arms or legs, neurological symptoms such as sensory loss, or both.
The spine consists of a number of vertebrae. Each vertebra consists of a body at the front, and the complex posterior elements at the back. The bodies of adjacent vertebrae are separated by discs, and the posterior elements form 2 joints between each level – 1 on each side. The posterior elements form the spinal canal which contains the spinal cord, and a pair of nerves emerges at each level – 1 on each side.
The disc can be thought of as being a bit like a car tyre. It has a tough, fibrous outer layer, and a soft inner which acts as a shock absorber.
What is not shown in the picture are the several muscles which support the spine and act to maintain its posture and move it around.
Back pain is very common. 80% of people will experience at least one episode of significant back pain during their life; at any one time about 15% of people will have some back pain. Fortunately back pain is usually self-limiting and only rarely becomes chronic. In general terms whatever device you may buy to treat your back pain, or whatever modality of treatment you choose to receive, you will get better. The passage of time is the main healer. The only “intervention” that has clearly been shown to be beneficial is to keep active, and not to put yourself to bed for weeks on end.
It is difficult, if not impossible to identify a cause for most back pains. MRI scanning is not the panacea that patients and a lot of professionals seem to think it is. Scanning is useful only to rule out potentially serious causes of pain that may be suspected depending on clinical presentation, or to confirm a diagnosis prior to surgery. Most back pain is best labelled “non-specific”.
Treatment for non-specific low back pain (NSLBP) should be activity, simple painkillers and sometimes physiotherapy to strengthen and co-ordinate the spinal muscles. The National Institute for Clinical Excellence (NICE) have published evidence on best practice in managing back pain. They have caused some controversy but seem to be basically sound - they can be read here
On the Isle of Man GPs now have access to the 'Map of Medicine' - online guidance in how best to manage various medical conditions, including back pain.
Whereas surgery for back pain is best avoided, spinal surgery to deal with nerve compression is generally very successful. Trapped nerves in the low back present with leg symptoms – either acute leg pain and numbness/tingling (sciatica) caused by a disc prolapse (“slipped disc”), or pain/numbness/weakness limiting walking in the case of generalised narrowing of the spinal canal (spinal stenosis). In the neck the equivalent problems give rise to acute arm pain in the case of a single trapped nerve, or balance/muscle control problems in the case of spinal cord compression.
Sciatica due to a prolapsed disc in the lumbar spine, and the equivalent condition in the arm, will generally resolve with time, although predicting how long resolution will take is impossible. Treatment is offered if symptoms are intolerable despite best medical treatment. Physiotherapy and other hands-on treatments have limited usefulness. Manipulation should definitely be avoided as it has no rational basis and can rarely make the situation worse.
Symptoms due to spinal stenosis, caused by wear and tear in the lumbar spine, can improve with time, but equally can get worse. Surgery is generally helpful.