Ankylosing spondylitis is described and is the most important cause of inflammatory back pain.
The term ‘disc disease’ is used to describe two common clinical problems which are due to degenerative change in the intervertebral disc, a process in cartilage which is not unlike OA. There is an acute syndrome in which disc prolapse causes conditions that are known to the public as either lumbago or sciatica, depending upon the presence or absence of radiation of the pain to the areas supplied by the sciatic nerve. It is also used to describe a chronic syndrome in which back pain is associated with ‘degenerative changes’ on X-ray. This chronic syndrome is sometimes called spondylosis. Chronic disc disease is often associated with OA of the apophyseal joints of the spine and it is difficult or impossible to separate the role of these two pathologies in the pathogenesis of symptoms. There is a very poor correlation between the presence of radiological changes and symptoms. Severe X-ray changes can be seen in patients without any appropriate symptoms and chronic back pain may also occur in patients with little radiological change.
Acute disc disease
Acute disc disease causes acute back pain (lumbago) with or without sciatic radiation (sciatica). The severity of this syndrome is enormously variable, from a brief and trivial episode to a long and difficult illness that occasionally requires surgical intervention. It is predominantly a disease of younger people with a peale incidence between the ages of 20 and 40 years, since the disc degenerates with age and is no longer capable of prolapse in the elderly. In older patients, sciatica is more likely to be due to compression of the nerve root by osteophytes in the lateral recess of the spinal canal.
The back pain is sudden, often severe and often continuous at first. Its onset may be associated with a feeling thatsomething has ‘gone’ in the back. This may occur after some strenuous activity, typically with the back in forward flexion. The pain is often clearly related to position and at first the back may be fixed in forward flexion. The pain is aggravated by movement and by certain activities. The radiation of the pain and various examination findings are dependent upon the disc affected; these features are summarized. The three lowest discs account for most cases of disc disease; in order of frequency, they are the LS/S1, L4/LS and L3/L4 discs. In a mild case there may be no signs at all, but characteristic findings include loss of lumbar lordosis, sometimes a compensatory scoliosis and limitation of movement in all directions. Severe neurological problems such as foot-drop or bladder or bowel dysfunction are fortunately rare.
Investigations are of very limited value in acute disc disease. X-rays do not visualize the disc itself, although there may be narrowing at the level of the lesion. MRI scanning is usually reserved for patients in whom surgery is beingconsidered and is unnecessary in most cases.
Treatment probably has little effect on the duration of the disease and is therefore aimed at the relief of symptoms and the maintenance of a reasonable way of life forthe duration of the illness. In the acute stage:
REST for a few days on a firm bed. Longer periods of rest are unnecessary except in the most severe cases. CORSETS may be used in the acute stage. DRUGS: analgesics to relieve pain; anti-inflammatory drugs if required, for example for pain at night or morning stiffness; diazepam for short periods as a muscle relaxant.
EPIDURAL CORTICOSTEROID INJECTION reduces pain and speeds recovery but is unpleasant and requires hospitalization. It is worth considering for acute sciatica hat is not responding to simpler measures.
SURGERY is required in the acute stage only for severe or increasing neurological impairment, e.g. foot-drop or bladder symptoms. In the recovery stage, which usually begins within a few days of the acute episode:
PHYSIOTHERAPY to relieve pain, correct posture and restore movement. A particularly useful technique is Maitland mobilization, which begins with careful assessment by the therapist to determine levels involved and restriction of movement. Applied movements with local pressure are then used to mobilize individual segments of the lumbar spine. An exercise programme is often useful at this stage. The MacKenzie approach to back care is a self-help system of exercises that emphasize extension, and includes advice about everyday activities that is useful both in treatment and in the prevention of recurrence.
URGERYwill be required for a small proportion of patients «1%) who fail to recover after an adequate period of conservative therapy.
COURSE AND PROGNOSIS
Most cases of acute lumbar disc prolapse recover completely,though the process may take as long as 1 year. A small proportion of patients fail to recover and mayrequire surgery. An MRI scan is required to pin-point the lesion as closely as possible, thus improving the prospects of surgery. The simplest operation is removal of the prolapsed disc (microdiscectomy).
Chronic disc disease and osteoarthritis
This very common syndrome is characterized by the presence of chronic low back pain associated with ‘degenerative’changes in the lower lumbar discs and apophyseal joints. Pain in these cases is of the mechanical type and is typically aggravated by exercise, although there may be an inflammatory component, reflected in a brief period of morning stiffness. Sciatic radiation of the pain may occur and there may be a past history of acute disc prolapse. In many cases, the pain is long-standing and the prospects for cure are very limited. Nevertheless, there are measures that will alleviate a difficult situation; DRUGS. Analgesic or anti-inflammatory drugs to relieve pain. PHYSIOTHERAPY. The same techniques are used as in acute disc prolapse, described above, and with the same aims. Maitland mobilization is useful when there is restriction of movement. An exercise programme, such as the MacKenzie approach, is usually required and it may be necessary to try different types of programme to achieve the desired result. BACK CARE. Advice about way of life, lifting, firm beds and other aspects of daily living is essential to identify and remove aetiological factors as well as preventing recurrence. Many physiotherapy departments have ‘back’ schools for this purpose.
CORSETS should be avoided. They may be useful for patients with mechanical abnormalities, such as instability, or a spondylolisthesis, but are grossly overprescribed. Fortunately, many patients have the good sense not to wear them!
SURGERY should be considered especially for a patient with severe pain of mechanical origin, arising from a single identifiable level, that has failed to respond to conservative measures. Fusion at this level would be appropriate together with decompression of affected nerve roots. The results of surgery for chronic disc disease are not particularly good-about 50% of patients recovering completely-and a failed operation is a demoralizing event in the course of a chronic illness.
WEIGHT REDUCTION may help obese patients.
PAIN RELIEF can be achieved in many other waysincluding acupuncture, transcutaneous nerve stimulation, massage, hypnosis and faith healing.