Back pain, ventilatory function, chest symptoms, and smoking.

Tests of ventilatory function were made and a history of previous back pain was obtained from 909 volunteers (592 men and 317 women). One year later, using postal questionnaires, they were asked about their experience of back pain in the ensuing 12 months and about smoking habits, breathlessness, coughing, and the bringing up of phlegm. From the frequency of their experience of back pain, the population was divided into "nonbacks," "mild backs," and "chronic backs." From their answers to the MRC Questionnaire on respiratory symptoms they were divided first into good, mild, and bad with regard to chest symptoms; and also into smokers, exsmokers, and nonsmokers. Ventilatory function tests were reduced in both smokers and "bad chests" and chest symptoms were significantly worse in smokers. Women with back pain were more likely to be smokers, but men with back pain were not. Chest symptoms were significantly worse in "chronic backs," whether men or women. The results suggest that previous reports of a relation between smoking and back pain arose incidentally from the associations between (a) chest and back symptoms and (b) chest symptoms and smoking.

The importance of heel compression in the measurement of diurnal stature variation.

Heel pad thickness was measured in 20 subjects (18 males aged 21-39 years and two females aged 21 and 25 years) using a 2 MHz ultrasound transducer linked to an Echo Scan body composition meter, Thandar SC110A oscilloscope and M150 amplifier. With the subjects standing erect and weight-bearing equally through both feet, the average time to achieve equilibrium heel compression was 81.7 s. Compression of the heel pad soft tissue averaged 4.4 mm (range 0.8-8.9 mm). Following equilibrium with one foot weight-bearing, an additional average loss of 1.6 mm of thickness (range 0-4 mm) was observed occurring after an average time period of 51 s. This study has confirmed the suspicion that heel pad shrinkage may be a confounding factor in measurements of change of stature. The results of this study have indicated that a period of 2 min is needed for the heel pad thickness to compress sufficiently before measurements are taken.

1987 Volvo award in clinical sciences. The perception of back pain and the role of psychophysical tests of lifting capacity.

In order to study the predictive value of pre-employment screening tests, a volunteer population of 1,741 men and 1,150 women was questioned about their experience of low-back pain (LBP) and their perception of physical exertion at work. They undertook a battery of tests, including psychophysical assessments of lifting capacity, and they were followed up by postal questionnaire after 1 year. The response rate was 88.7%. The psychophysical tests have proved to be simple and inexpensive to administer; in good hands, they are repeatable. Although psychophysical lifting capacity was less in those with previous LBP, the psychophysical strength tests were poor predictors of future LBP. But when the previous history of LBP was known, then the test results significantly enhanced the prediction.

Diurnal variations in spinal loading and the effects on stature: a preliminary study of nursing activities.

A new method for recording the postures and activities of nurses has been developed. Using a simple coding system, each change in posture or activity was entered on a portable microcomputer and the results stored on cassette, thus creating a real time-based, permanent record for subsequent analysis of the frequency and duration. of each posture and activity. Twelve nurses from six different wards were observed throughout two full working shifts. At intervals during the working shifts, stature of the nurses was measured to an accuracy of at least 1 mm and, for comparison, the diurnal change in stature on their days off. Overall loss of stature was greater during the 8-h working shifts than during a 12-h period on their days off. There were significant correlations between loss of stature and both the total duration of lean/stoop postures and the total duration of lifting.