Nocturnal leg cramps: a common complaint in patients with lumbar spinal canal stenosis.

STUDY DESIGN: Questionnaire survey on leg cramps for patients with lumbar spinal canal stenosis (LCS).

OBJECTIVE: To evaluate the prevalence of leg cramps in patients with LCS treated surgically and the relationship between leg cramps and the surgical outcomes.

SUMMARY OF BACKGROUND DATA: Although it has been anecdotally reported that LCS patients have suffered from leg cramps, the true prevalence remains unknown.

METHODS: One hundred twenty LCS patients who underwent decompression surgery (men 85, women 35, mean age 73.5) and 370 elderly subjects from the general population (men 162, women 208, mean age 75.6) were enrolled in the study. The participants filled in a questionnaire regarding: (all participants) (1) experience of leg cramps, (2) frequency and time of the day of the cramp attacks; (for LCS patients only), (3) changes in cramps before and after surgery, (4) activities of daily living disturbance because of leg cramps, (5) satisfaction with surgery and walking ability, (6) the Roland-Morris Disability Questionnaire, and (7) the Oswestry Disability Index.

RESULTS: Eighty-five (70.8%) patients with LCS and 137 (37.2%) of the control population experienced leg cramps (age and sex adjusted odds ratio; 4.6, P < 0.01). Leg cramps occurred once or twice a week in 34.9% of the LCS group and once in several months in 44.5% of the control group, and occurred nocturnally in 73.3% of the LCS patients and in 91.6% of the control group. In LCS patients, leg cramps improved after surgery in 18.2%, remained unchanged in 45.5%, and worsened in 26.1%, and activities of daily living were disturbed in 47.6%. There was no significant difference in satisfaction with surgery, the Oswestry Disability Index, the Roland-Morris Disability Questionnaire scores, or walking ability between the LCS patients with or without leg cramps.

CONCLUSION: LCS patients had significantly more frequent attacks of nocturnal leg cramps than the control population, and leg cramps disturbed the quality of the patients' life, and they rarely improved after decompression surgery. Leg cramps should be recognized as one of the symptoms of LCS, which disturb the patients' quality of life.