John W. Frymoyer

Back pain and sciatica

LOW back pain is usually a self-limiting symptom, but it costs at least

Risk factors in low-back pain. An epidemiological survey.

16 billion each year1 , 2 and disables 5.4 million Americans.3 The fact that a benign physical condition has such an importa...

Epidemiologic Studies of Low-back Pain

ABSTRACTA survey was done on 1221 men between the ages of eighteen and fifty-five years who had been seen in a family-practice facility between 1975 and 1978 Each patient completed a questionnaire concerning any history of low-back pain, associated symptoms in the lower limbs, resultant disability, types of health care utilized, certain occupational characteristics, exposure to vehicular vibration, and sports activities. We found that 368 patients (30. 1 per cent) had never experienced low-back pain, 565 (46.3 per cent) had or were having moderate low-back pain, and 288 (23.6 percent) had or were having severe low-back pain. Patients with severe low-back pain had significantly more complaints in the lower limbs, sought more medical care and treatment for the low-back pain, and had lost more time from work for this reason. Risk factors associated with severe low-back pain included jobs requiring repetitive heavy lifting, the use of jackhammers or machine tools, and the operation of motor vehicles. Patients with severe pain were more likely to be cigarette-smokers and had a greater tobacco consumption as measured by both the number of cigarettes smoked per day and the number of years of exposure. Patients with moderate low-back pain were more often joggers and cross-country skiers when compared with the asymptomatic men and the men with severe low back pain. Otherwise, there were no identifiable differences related to sports activity.

Functional restoration with behavioral support: a one-year prospective study of patients with chronic low-back pain

The records of 3920 patients (2068 females, 1852 males) entering a model family practice unit between 1975 and 1978 have been analyzed. Eleven percent of males and 9.5% of females reported an episode of low-back pain during that 3-year interval. The complaint of medically reported low-back pain was significantly related to occupational factors such as truck driving (P<0.001), lifting, carrying, pulling, pushing, and twisting (P<0.001 for all variables) as well as nondriving vibrational exposure (P<0.001). Patients reporting low-back pain also reported more episodes of anxiety (P<0.001) and depression (P<0.001) and had more emotionally stressful occupations (P<0.001). The mean number of pregnancies was greater in women with low-back pain (2.6) than in those without (1.6) (P<0.001). The low-back pain sufferers were more likely to be cigarette smokers (P<0.001), particularly when smoking was accompanied by a chronic cough (P<0.001). This population is currently under prospective study to define the relevance of each of these risk factors to the complaint of low-back pain.

A comparison of radiographic findings in fusion and nonfusion patients ten or more years following lumbar disc surgery.

Patients with chronic disabling low-back pain have poor prospects of returning to work. The authors tested a treatment program of functional restoration with behavioral support through 1 year prospective observation of patients disabled for an average of 19 months without evidence of surgically correctable disease. Ninety patients were studied: 59 program graduates, five program dropouts, 17 patients denied program authorization by their Insurance carriers, and six crossover patients. Three patients were admitted but refused to participate in the treatment program. Initial demographic, physical, and self-assessment attributes were similar for all four groups. At years end, 81% of program graduates, 40% of the dropouts, and 29% of those denied the program had returned to work. All six crossover patients were working 6 months after treatment. Program graduates showed significant improvements in self-assessed pain, disability, and depression, and in physical capacities after 3 weeks of treatment. These improvements were maintained through the year except for partial decreases in frequent lifting, cycling endurance, and isokinetic trunk extension strength. Functional restoration with behavioral support is an effective treatment for patients with chronic, disabling low-back pain, as measured by self-assessments, physical capacities, and return to work.

Determinants of return-to-work among low back pain patients

Ninety-six patients who had undergone disc excision and midline spinal fusion and 36 patients who had had simple disc excision had spinal radiographs made 10 or more years postoperatively. Claw spurs were found most commonly at the L2-3 and L3-4 levels in fusion patients, particularly male laborers. Traction spurs with segmental hypermobility were found more commonly at the L4-5 level in patients whose spines were not fused, particularly women. Total lumbar flexion-extension was greater in nonfusion than in fusion patients, but the L1 - 3 mobility was greater in those who had undergone fusion, suggesting a compensatory increase in the range of lumbar motion. Segmental mobility at levels of surgery in nonfusion patients was similar in those with good and those with poor clinical results. Disc space narrowing was common at levels of operation, but did not correspond to the clinical result. Pseudarthrosis was demonstrated in 26% of fusion patients, but was of no clinical significance. Although complex radiographic changes follow lumbar disc surgery, with or without failure, it is concluded that the plane radiograph is of little aid in determining the source of postoperative pain. The sole exception is that of acquired spondylolysis, which was found in 2.5% of this group of fusion patients, and was clearly associated with a poor clinical outcome. Symptomatic degenerative disc disease at levels above lumbar spinal fusions appears to be an uncommon clinical problem.

Spine radiographs in patients with low-back pain. An epidemiological study in men.

&NA; This prospective study identifies physical, behavioral, and psychosocial correlates of subsequent employment status in a sample of low back pain patients. The sample of 150 subjects was drawn from 2 populations of persons with chronic low back pain: 87 individuals who were receiving care at a university low back pain clinic, and 63 individuals who had applied for (but not yet received) Social Security compensation on the basis of low back pain. All subjects had worked at least 3 months prior to their latest unemployment period and were currently out of work. Initial assessment included a medical history, physical examination, biomechanical testing, psychiatric interview, and MMPI testing. All subjects were followed up 6 months later to determine whether they had returned to work. Cross‐sectional group comparisons at the time of initial assessment showed that, after controlling for the effects of age, the two samples differed on several physical and biomechanical measures, the Social Security group reflecting a more chronic picture. Group differences on physical variables were found, but most significant differences disappeared when adjusted for length of time out‐of‐work. Longitudinal analyses showed that few objective physical or biomechanical measures were associated with return‐to‐work at 6 months, while a number of psychosocial variables were significant predictors of 6‐month work status. The data suggest that exclusive reliance on the physical examination to determine level of disability, without consideration of psychosocial conditions, and without adjusting for the confounding effects of age and length of time out‐of‐work, is not empirically justified. Logistic regression analysis was used to ascertain the relative contribution of each predictor to outcome and to illustrate the hypothetical effects of changes in the levels of selected risk factors on the likelihood of return‐to‐work. Implications for interventions with low back pain patients are discussed and future research directions suggested.

Identifying patients at risk of becoming disabled because of low-back pain : the Vermont rehabilitation engineering center predictive model

A cohort of 321 men between the ages of eighteen and fifty-five was randomly selected from a group of 1221 men who had been surveyed by a questionnaire. They then had radiographs made of the lumbar spine. Of the 292 subjects fulfilling the criteria for inclusion in the study, ninety-six (32.9 per cent) had never had low-back pain, 134 (45.9 per cent) had had or were having moderate low-back pain, and sixty-two (21.2 per cent) had had or were having severe low-back pain. In the three groups there was a similar frequency of transitional vertebrae, Schmorls nodes, the disc vacuum sign, narrowing of the disc space between the third and fourth lumbar and the fifth lumbar and first sacral vertebrae, and claw spurs. When there were traction spurs or disc-space narrowing, or both, between the fourth and fifth lumbar vertebrae, an increased incidence of severe low-back pain was evident. There also was a significant association of these two radiographic findings with symptoms (pain, weakness, and numbness) in the lower limbs. The measured lumbar lordosis, the length of the transverse process of the fourth lumbar vertebra, and the relationship between the fourth and fifth lumbar vertebral bodies with reference to the intercristal line had no association with the low-back pain. Increased lumbar lordosis had a significant association with decreased disc-space height and wedging deformity of the disc between the fourth and fifth lumbar vertebrae.(ABSTRACT TRUNCATED AT 250 WORDS)

Predicting disability from low back pain.

A predictive risk model of low-back pain (LBP) disability was developed by a panel of six experts in the fields of chronic pain and disability. It comprised 28 factors organized into eight categories: job, psychosocial, injury, diagnostic, demographic, medical history, health behaviors, and anthropometric characteristics and was administered as a 15-minute written questionnaire. The model was tested prospectively on 250 patients (age range, 18-65 years) attending two secondary-care low-back clinics. Disability, as predicted by the model, was compared with 1) actual disability assessed 3 and 6 months later; 2) predictions of disability made by the attending physicians; and 3) predictions obtained from an empirically derived model. These results showed that 1) the expert-generated risk model had a predictive accuracy of 89% and did better in predicting disability than the physicians across all samples and 2) the empirically weighted model did best of all (91% predictive accuracy), suggesting that the expert model used appropriate factors but that the weights assigned to these factors by the panel of experts could be improved.

The relationship between anthropometric, postural, muscular, and mobility characteristics of males ages 18-55

Since World War II, the incidence of chronic low back disability has increased dramatically, at a rate disproportionate to all other health conditions. The factors that contribute to this disability are reviewed. Psychosocial and work environmental factors are far more accurate predictors of disability than physical factors. A predictive risk model is described that allows an estimate of the patients risk of becoming chronically disabled early in the course of a low back pain episode. This model demonstrates that work environment, perception of compensability, and the duration of the current episode are significantly predictors. Surprisingly, psychologic factors, as measured by the Minnesota Multiphasic Personality Inventory (MMPI), are not predictive in the cohorts studied to date. Although there are inherent limitations in study design, the results offer additional credence to the hypothesis that low back pain disability is often the result of psychosocial and work environmental factors. The model may also be used to address the hypothesis that patients at risk for future disability are more effectively treated by early, aggressive rehabilitation programs.