Non-mechanical disorders of the lumbar spine
Warning signs
Introduction
The majority of lumbar spine syndromes encountered in clinical practice result from mechanical – activity-related – disorders. They can be classified into dural, ligamentous and stenotic syndromes. Lumbar syndromes, however, can also stem from non-mechanical – non-activity-related – disorders affecting the spine. These are: inflammatory diseases, both septic and rheumatological; tumours and infiltrative lesions; metabolic disorders; and acquired defects in the neural arch. Finally, pain in the lower back, groin and pelvic area can be referred from visceral organs (see online chapter Disorders of the thoracic cage and abdomen). Pain in buttocks, groin and limb, as the result of reference from the sacroiliac and hip joints, although ‘activity-related’, does not have a spinal origin and is discussed thoroughly in the chapters on the hip joint and sacroiliac joint.
Although the occurrence of non-mechanical (non-activity-related) disorders is rare, it is important to differentiate them as quickly as possible from mechanical activity-related lesions. This is never easy, because these disorders frequently mimic other, more specific lumbar lesions. Sometimes the diagnosis is made radiologically but very often this is of no help, especially in the early stages of an inflammatory or neoplastic disease. A thorough history and clinical examination are what will first draw attention to the possibility of a non-activity-related disorder: the history may show an unusual localization or an atypical evolution of the pain; particular clinical signs may arouse suspicion. Most of all, however, it is the comparison between history and clinical examination, resulting in the existence of ‘unlikelihoods’, that focuses attention on serious spinal pathology such as vertebral fracture, malignancy, infection or inflammatory disease.1
Warning signs in backache and sciatica
Symptoms and signs that almost invariably point to non-mechanical disorders are termed ‘warning signs’ here. The finding of such signs indicates that the existence of a non-specific disorder in the lumbar spine is very likely. A patient presenting with a warning sign should never be considered to be suffering from a common mechanical disorder until the contrary has been proved. It is important, therefore, always to have confirmatory investigations carried out (radiography, bone scan, computed tomography (CT) and blood tests) to settle the diagnosis. It is also the duty of a physiotherapist who is asked to give active treatment (manipulation or traction) to a patient presenting with warning signs to report this to the referring doctor, and to send the patient back with a request for further thorough examination.2
Warning
Symptoms
Significant trauma
It is obvious that the statement of a significant trauma prior to the development of backache should be reason to ask for further imaging studies, especially if the patient is aged over 70 years and uses corticosteroids.3,4
Deteriorating general health
Unexplained weight loss, fever, feeling systematically unwell (tired, loss of appetite) and a previous history of cancer are all considered as potential symptoms of a serious illness.5
Pain in the ‘forbidden area’
In the upper lumbar region pain is very seldom the result of a mechanical lesion. Disc lesions almost never occur at the first and second levels,6 and even third lumbar lesions constitute only 5% of lumbar disorders.7 Also, ligamentous lesions and recess stenosis do not seem to occur at these upper lumbar levels. Hence, if a patient has pain at the upper lumbar level – the ‘forbidden area’ (Fig. 39.1) – the suspicion is aroused that a non-mechanical lesion is present. Ankylosing spondylitis, neoplasm, tuberculosis, aortic thrombosis or reference from a viscus may then be possibilities (Cyriax8: p. 26).
Fig 39.1 The ‘forbidden area’.
