gms | German Medical Science

Objective: To determine whether the clinical outcome of primary spinal surgery for lumbar disc herniation is better than the result of secondary surgical intervention after conservative treatment and to further reveal differences in economic costs due to sick leave between early and late intervention.

Method: The study included 156 patients with a median age of 50 years. The patients were divided according to the duration of their prior treatment: cohort 1 received surgery after a short period of conservative treatment of max. 12 weeks whereas cohort 2 went through late surgery after 12-36 weeks of failed outpatient care. Both cohorts were matched post hoc in a ratio of 1:1 with 78 patients in each group and matching criteria sex, age and Patient Clinical Complexity Level (PCCL). We examined the level of disability one day before and 6 months after surgery with percentage change in Oswestry Low Back Pain Disability Index (ODI), defined as primary endpoint and its intra-pair difference specified as effect measure. The 6 months percentage change of quality of life index EuroQuol EQ-5D (EQ) was used as secondary endpoint. For cost calculations we analyzed the collected sociodemographic data about employment status and course of disease as well as the 2011 branch specific average rates for production – and economic value loss per day of sick-leave of the BAuA.

Results: The median intra-individual change of the ODI pre- versus post-surgery was 36% for cohort 1 and 32% for cohort 2. No significant difference was found in the effect measure (median 3% with 95% confidence interval – 8%; + 18%, confirmed by a sign test with p-value 0,649 at significance level of 5%). The results for the secondary endpoint affirmed this tendency with median intra-individual changes in EQ of 44% for cohort 1, 50% for cohort 2 and a median intra-pair difference of 2% (95% confidence interval – 20%; + 17% and p-value 0,909 at significance level of 5%). The calculated per capita costs for pre-operative sick-leave reached 5.237 EUR for cohort 1 and 10.040 EUR for cohort 2 patients.

Conclusions: Despite remarkable improvements in both cohorts in the course of 6 months, the findings indicate that the result of early surgical intervention in lumbar disc herniation is not significantly superior to the outcome of late surgery after failed conservative therapy. Further analysis revealed that a longer duration of pre-operative treatment leads to considerably higher health expenditures per capita, mainly due to sick-leave before surgery.