Filum terminale lipomas - the role of intraoperative neuromonitoring

Fibrofatty filum terminale: long-term outcomes from a Singapore children's hospital

OBJECTIVE

The role of prophylactic detethering a fibrofatty filum terminale (FFT) remains equivocal. Furthermore, long-term studies focusing on urological outcomes are sparse. The aims of this study were to present an institutional experience on the perioperative and long-term outcomes of FFT surgery and to assess for factors that contribute to postoperative clean intermittent catheterization (CIC).

METHODS

This was a single-institution, retrospective study conducted over a 20-year period. Patients younger than 19 years of age who underwent surgery for FFT were included. Variables of interest included patient demographics, clinical presentation, radiological findings, postoperative complications, and long-term need for CIC. Outcomes were measured using the Necker functional score and modified Hoffer Functional Ambulation scale score at 3, 6, and 12 months postdischarge.

RESULTS

A total of 164 surgeries were performed for FFT from 2000 to 2020. The median age at surgery was 1.1 years, and the mean follow-up duration was 8.3 years. There were 115 patients (70.1%) who underwent prophylactic-intent surgery and 49 patients (29.9%) who underwent therapeutic-intent surgery. The proportion of therapeutic-intent surgeries increased significantly with age percentiles (0-20th, 21.9%; 20th-40th, 9.1%; 40th-60th, 18.2%; 60th-80th, 36.4%; and 80th-100th, 63.6% [p < 0.001]). Thirty patients (18.3%) had an associated syndrome, the most common (n = 19, 11.6%) being VACTERL (vertebral defects, anal atresia, cardiac defects, tracheo-esophageal fistula, renal anomalies, and limb abnormalities). Forty-eight patients (29.3%) had an associated malformation (anorectal anomaly = 37, urogenital anomaly = 16, and sacral anomaly = 3). Cutaneous manifestation was the most common presentation (n = 96, 58.5%), followed by lower-limb neurological deficits (n = 21, 12.8%). A low-lying conus was present in 36.0% of patients (n = 59), and 16.5% had an associated syrinx (n = 27). There were 26 patients (18.8%) with an abnormal preoperative urodynamic study. Three patients (1.8%) had postoperative complications that required repeat surgery. There were no cases of CSF leakage. One patient (0.6%) developed retethering requiring another surgery. Postoperative CIC was required in 11 patients (6.7%). Multivariable analyses showed that an abnormal preoperative urodynamic study (adjusted OR 5.5 [95% CI 1.27-23.9], p = 0.023) and having an intraspinal syrinx (adjusted OR 5.29 [95% CI 1.06-26.4], p = 0.042) were associated with the need for CIC.

CONCLUSIONS

The authors' results demonstrate that detethering surgery for FFT is a relatively safe procedure and can be performed prophylactically. Nonetheless, the risks of postoperative CIC should be emphasized during the preoperative counseling process.

Updates on Intraoperative Neurophysiology During Surgery for Spinal Dysraphism

Spinal dysraphism is a group of disorders resulting from an embryologic failure of spinal cord development which can lead to a radicular-medullary mechanical stretch that generates vascular compromise and hypoxic-ischemic damage to the nervous structures of the conus-cauda region.Thus, the clinical relevance of the different types of spinal dysraphism is related to the possible neurologic deficits resulting from spinal cord tethering. The clinical presentation is heterogenous: from asymptomatic to very compromised patients. The indications and the time of a detethering surgery are still subject of debate, although there is an agreement on the high standards of treatment that have to be offered by the surgery. Intraoperative neurophysiology (ION) contributes to the safety of tethered cord surgery in reducing the risks of iatrogenic neurological damages.

Reduced complication rate with simultaneous detethering and spinal deformity correction surgery compared to staged surgeries in patients with early onset scoliosis

PURPOSE

In patients with early onset scoliosis (EOS) and intraspinal anomalies, surgery may be necessary for both the tethered spinal cord (TSC) and spinal deformity. The purpose of this study was to determine if there is a difference in complications when TSC release and surgery for spinal deformity correction (SDC) are performed separately compared simultaneously.

METHODS

EOS patients with TSC who underwent detethering and SDC surgeries were identified through a multicenter registry. Patients were stratified into two groups. The simultaneous cohort consisted of patients receiving both detethering and SDC surgeries in a single anesthetic event on the same day, and the staged cohort consisted of patients undergoing detethering and SDC on two separate occasions. Postoperative complications up to 180 days for either surgery were assessed.

RESULTS

Twenty five (65.8%) patients were staged and 13 (34.2%) underwent a simultaneous approach. Percent curve correction following SDC surgery did not significantly differ between the groups (p = 0.36). Within 90 days postoperatively, 16 complications in 11 patients (44.0%) occurred in the staged group, whereas no complications occurred in the simultaneous cohort (p = 0.006). From 90-days to 180-days postoperatively, 4 additional complications in 3 patients (12.0%) occurred in the staged group, with no complications reported in the same timeframe for the simultaneous cohort.

CONCLUSION

To our knowledge, this is the largest multicenter comparative study to date, and it suggests that a simultaneous approach can be performed safely for EOS patients undergoing detethering and SDC surgeries, with a potentially lower risk profile than the traditional staged approach to these pathologies.

LEVEL OF EVIDENCE

Level III.