[Long-term socioeconomic outcome of lumbar disc microsurgery]

Abstract

Lumbar disc surgery is frequently performed but only few long-term outcome studies have been published. To assess the socioeconomic long-term outcome after lumbar disc surgery this study was performed using the Functional Economic Rating scale developed by Prolo et al. in 1986. The study group, mailed a questionnaire, consisted of 663 patients (18 to 60 years) operated on in 1983 or 1984. 23 patients (3.5%) died in the follow-up period. 406 (66% male and 34% female) patients answered the questionnaires (61%), therefore being eligible for further investigation. Mean age at the time of operation was 43 +/- 9.5 years. Preoperatively 29% of patients did sedentary work, 46% were employed in less strenuous and 25% in strenuous occupations. A motor deficit was present in 59% of patients preoperatively. In 51% the L4/5 level and in 38% the L5/S1 level was operated; 5% were operated in more than one level. In 45% an intraspinal sequester was found intraoperatively. Intra- and postoperative complications occurred in 14 patients (complication rate 3.4%). Six weeks after surgery all patients were examined in our outpatient department. 93% were more or less relieved of their complaints. 10 years after lumbar disc surgery a good outcome defined as Prolo scale 8-10 was achieved in 38%, a moderate outcome (Prolo scale 6-7) in 40% and a poor outcome (Prolo scale < 5) in 22%, respectively. Patients with strenuous occupations had a significantly (p < 0.001) less favorable outcome than patients with less strenuous or sedentary occupations. 32% were able to work in the previous profession with no restrictions. 42% were able to work part time at the previous occupation or with limited status and 9% had to change their profession. 17% were not able to gain any occupation postoperatively and retired. Vocational consequences depended on the preoperative type of occupation. 54% of patients with strenuous occupations had to change the profession or to retire compared to 15% of patients with sedentary occupations. During the 10-year follow-up period, 125 patients (31%) underwent at least another lumbar disc operation 4.8 +/- 3.8 years after their first surgery. Recurrence at the same level and the same side occurred in 14%. Reoperated patients had a significantly (p < 0.001) less favorable outcome than patients not operated on again. The results of this study indicate the recommendation of a prolonged postoperative course of treatment, especially in patients with strenuous occupations.