The use of muscle relaxant medications in acute low back pain.

STUDY DESIGN

Prospective cohort study.

OBJECTIVES

To determine the characteristics of patients who take muscle relaxants for back pain after seeking care and to determine the relationship of muscle relaxant use with recovery from the episode of low back pain.

SUMMARY OF BACKGROUND DATA

Low back pain is a common condition with a generally favorable short-term prognosis. Physicians in the acute setting commonly prescribe muscle relaxants. The indications for use and outcomes are not clear.

METHODS

We performed a secondary data analysis of a cohort of 1633 patients who sought care from a variety of practitioners (primary care, physician of chiropractic, orthopedic surgeon, Health Maintenance Organization) for low back pain. Patients were enrolled in the physician's office and interviewed at baseline, 2, 4, 8, 12, and 24 weeks. Pain, functional status, medication use, health care utilization, and satisfaction with care were assessed.

RESULTS

Muscle relaxants were used by 49% of patients; among those who sought care from doctors, 64% used muscle relaxants. Muscle relaxant users were more impaired at baseline. Over time, among patients with greater functional status impairment (Roland disability score > 12) at baseline, muscle relaxant users had somewhat slower recovery from the episode of back pain. This finding persisted after controlling for baseline functional status, age, worker's compensation status, and use of nonsteroidal inflammatory agents.

CONCLUSIONS

Use of muscle relaxants was very common among patients with acute low back pain. Muscle relaxant use was not associated with more rapid functional recovery.