PSYCHOMOTOR SPEED AND POSTURAL CONTROL IN CHRONIC LOW-BACK-PAIN PATIENTS - A CONTROLLED FOLLOW-UP-STUDY

Study Design. Psychomotor speed (reaction time) and postural control ( center point of force velocity) among healthy control volunteers and p atients with chronic low back pain (LBP) were studied at the beginning of an active, functional, restoration back rehabilitation program and 6 months after the program. Objectives. To study cross-sectionally re action times and center points of force velocity among control volunte ers and patients with low back pain, and to evaluate the effects of th e restoration on these measures of motor function in a follow-up exami nation. Summary of Background Data. Deficits of motor skills and of co ordination have been reported in association with musculoskeletal diso rders, but one can only speculate about an association between proprio ceptive dysfunction and low back disorders on the basis of the current ly available data. Methods. Sixty-one healthy control volunteers and 9 9 patients with low back pain-68 of these patients experienced moderat e pain; 31 experienced severe pain-participated in the study. Reaction times for upper and lower limbs were tested with a system based on a microcomputer. Postural stability was measured with a vertical force p latform. Results. A consistent trend was found in which patients with low back pain had reaction times slower than those of control voluntee rs. Men with severe low back pain had significantly longer hand reacti on times than men in the control group (P = 0.03). Women with severe l ow back pain also had poorer postural control than women with moderate low back pain (P = 0.02) and women in the control group (P = 0.04). F unctional restoration seemed to have an effect on reaction times. The restoration was considered successful if the condition of a patient wi th a disability that had resulted from low back pain improved during t he follow-up examination and unsuccessful if the disability worsened. Patients who experienced these results were identified in groups calle d ''good'' and ''poor,'' respectively. Among men, the reaction times i mproved in the control group and ''good'' groups, but they became slow er in the ''poor'' group. The difference between ''good'' and ''poor'' groups was significant (P = 0.008). Women in the ''good'' groups was significant (P = 0.008). Women in the ''good'' group achieved the most improved reaction times, and the difference between these women and t he control women almost reached significance (P = 0.076). Conclusion. The results indicate that patients with chronic low back pain have imp aired psychomotor speed and among women, impaired postural control. Ps ychomotor speed improved during an active, functional, restoration bac k rehabilitation program.