The importance of timing: evaluating the optimal age for surgical intervention in asymptomatic dermal sinus tracts.

Objective: Dermal sinus tracts (DSTs) are rare congenital lesions resulting from errors of spinal cord disjunction, leading to a persistent connection between the cutaneous ectoderm and underlying neural elements. As patients are at increased risk of infection and irreversible neurological compromise due to tethering, resection and detethering are recommended as a prophylactic measure. The ideal timing of surgical intervention in an asymptomatic cohort, however, remains unclear.

Methods: A retrospective chart review was performed at a single institution from 1998 to 2022 of all patients surgically treated for lumbar DST by 10 different surgeons. Demographic, presentation, operative, and postoperative details were obtained. Five patients who presented with infectious or neurological symptoms were excluded from primary analysis. The age at the time of surgery was then analyzed as a continuous variable against the operative details and postoperative outcomes utilizing Spearman's correlation coefficient and the Mann-Whitney U-test.

Results: Fifty-two patients underwent prophylactic surgical excision of their DST as well as detethering. Overall, 65% of patients were female and the median age at diagnosis was 3 months, while the median age at the time of surgery was 7 months. An additional cutaneous finding was identified in 71% of patients, with hemangioma being most frequent (40%). Additional spinal lesions were radiographically identified in 29% of patients, including lipoma (19%), dermoid and epidermoid inclusion cysts (8%), and an arachnoid cyst (2%). Postoperative complications occurred in 8% (n = 4) of patients, primarily related to wound healing (3/4), with significant risk attributed to younger age at time of surgery (mean 3 months, range 1-5 months) (p = 0.01). During 56 months of follow-up, long-term rates of retethering (6%, p = 0.02) and abnormal neurological examinations (8%, p = 0.001) were associated with concurrent lipomas, but not with age at operation.

Conclusions: In a series of 52 pediatric patients undergoing prophylactic resection of a DST with detethering, the complication rate was 8% and was significantly associated with age < 6 months at the time of operation. Associated spinal lipomas significantly influenced long-term outcomes. When evaluating asymptomatic infants with DST, patient age is a significant factor in assessing the risks and benefits of surgical timing.