MMPI scale 3 as a predictor of back injury report: what does it tell us?

Items and selected subscales of Scale 3 (Hysteria) of the MMPI were examined to pinpoint personality or emotional factors predictive of back injury reports in an industrial setting. Data were derived from a previous prospective-design study of back pain in volunteer hourly wage employees of an aircraft manufacturing company. After physical examination and completion of questionnaires pertaining to demographic, psychosocial (including the MMPI), and workplace factors, workers were followed for an average of 3 years. Those who subsequently reported back injury were compared with those who did not. In that study three variables predicted report of back injury, one of which was Scale 3 of the MMPI. Individual items, Ornduff et al. subscales of Psychological Denial and Body Concern, and the five Harris-Lingoes (1955) subscales of Scale 3 were analyzed. Three Harris-Lingoes subscales showed significant relationships to the criterion. Hy-3: Lassitude/Malaise; Hy-1: Denial of Social Anxiety; and, marginally, Hy-2: Need for Affection, significantly contributed to prediction effectiveness. Results and implications for the understanding of factors predicting back injury reports and for the medical evaluation of pain and the concept of pain are discussed.

Isometric lifting strength as a predictor of industrial back pain reports.

The objective of our investigation was to study isometric lifting strength in a population of industrial workers who perform a great variety of manual tasks, and to determine whether isometric strength is predictive of future back problems in such a population. Of 3,020 study subjects, 2,178 (72%) underwent strength testing in three standard lifting positions. During a 4-year follow-up period, 172 subjects tested reported back problems. When examining each isometric lift separately as a predictor of industrial back pain reports, those with greater isometric strength were at significantly greater risk than were weaker workers. However, after controlling for the effects of age, only a slight trend remained. For the blue collar workers in this study, isometric lifting strength testing was ineffective in identifying individuals at risk for industrial back problems.

Spinal flexibility and individual factors that influence it.

We conducted an investigation to examine the spinal flexibility of a large, adult population and to study the effects of other individual physical characteristics on spinal range of motion. The study group consisted of 3,020 blue collar employees (2,350 men and 670 women) who underwent a physical examination that included assessments of standing and sitting height, weight, shoulder flexibility, and spinal flexibility in the sagittal and frontal planes. Flexibility measures were correlated positively to one another; however, lumbosacral flexion measurements assessed by the modified Schober method correlated to the other flexibility measurements to a much lesser degree. Age, sex, and height affected ROM, as did obesity and the ratio of standing height to sitting height. The study findings indicate that spinal ROM covers a wide spectrum of values and is affected by many individual factors. Any attempts to determine what is normal, excessive, or diminished must take into account variations caused by age, sex, and other physical attributes.