The conservative treatment of low back pain : a study of McKenzie physiotherapy and slow release ketoprofen
Acute low back pain: A randomised, controlled, prospective trial of ketoprofen and McKenzie physiotherapy within three weeks of onset. Aims: (1) To establish whether McKenzie physiotherapy is beneficial compared with a non steroidal anti inflammatory drug in the treatment of acute low back pain. (2) To investigate the mode of action of McKenzie lumbar spine treatment. Method: Patients with acute back pain of less than three weeks standing aged between 18 and 55 years were admitted to the trial. On attending clinic the patient underwent interview and examination by a doctor. Those patients without evidence of nerve root entrapment; underlying pathological lesion or psychological abnormality (illness behaviour) completed formal psychometric testing and social enquiry. The St Thomas back disability questionnaire was used throughout the study and was the principle outcome measure. Patients underwent randomisation into study and control groups. They both had information leaflets; and a supply of back disability questionnaires with stamped addressed envelopes to return to the study office at weekly intervals. Both groups were seen again on the seventh week after the onset of the back pain. Study Group Patients were assessed by one of two research physiotherapists and underwent a treatment regimen according to the McKenzie principles. Control Group Patients were given a 28 day course of non steroidal anti inflammatory drug. At follow up clinic repeated clinical examination and questioning recorded the following outcomes: disability; analog pain score; return to work; patient's appraisal of change in condition and personal responsibility for pain control. Further postal follow up occurred at six months and one year. Initial psychological factors explained much of the disability seen seven weeks after the onset of back pain. An analysis of covariance employing psychological information showed that physiotherapy was significantly more effective in reducing disability at the seventh week only when the 8.5% of patients who the physiotherapists were unable to diagnose on their first assessment were excluded from analysis. The physiotherapy patients were away from work significantly longer than the patients who had drug treatment. At six months and one year a tendency to less frequent attacks in the physiotherapy group was not significant owing to the power of the study. Physiotherapy patients became significantly more responsible for their pain than the drug patients when assessed by means of a pain locus of control questionnaire. This finding persisted at a year after onset.