Open vs tubular rate of re-operation for incidental durotomies after lumbar microdiscectomies: a propensity matched analysis.

Purpose: Incidental durotomy (ID) is a common complication in spine surgery and can lead to increase in length of stay, decreased satisfaction with surgery and pseudomeningocele formation. Here, we describe a retrospective study comparing ID occurrences and repairs between patients receiving traditional open versus tubular minimally invasive spine (MIS) microdiscectomy.

Methods: A retrospective comparative cohort-matched analysis was performed to study ID and its complications in MIS versus open lumbar microdiscectomies. The study included 192 patients in the tubular MIS cohort and 2902 patients in the open microdiscectomy cohort. Propensity scores were estimated by age and Elixhauser comorbidity score. After cohort matching, 156 patients were included in the open cohort. The difference in proportion for incidental durotomies, re-operation for pseudomeningocele, and levels were calculated using a Fisher's exact test.

Results: The total incidence of durotomy in our cohort of 348 patients was 3.1% (n = 11), 5 (3.2%) in the open cohort and 6 (3.1%) in the tubular cohort. Various ID repair techniques were used including primary repair and dural sealants. One patient in the open cohort required re-operation for pseudomeningocele formation while none required re-operation in the MIS cohort. This result was not significant (p = 0.45).

Conclusion: Pseudomeningocele formation after ID is rare. The rates of ID were similar between cohorts. We found no significant difference between re-operation rate for pseudomeningocele between the two cohorts. Larger, cohort-matched, prospective studies are needed to determine the true difference between rates of re-operation for pseudomeningocele formation after lumbar microdiscectomies.