gms | German Medical Science

Objective: Occult Spinal Dysraphism (OSD) is a group of congenital and pathological changes occurring in the spine and spinal cord characterized by different failure of the neurulation process. Tethered cord syndrome associated causes a progressive form of neurological deterioration. The objective of this study is to analyze our patients evaluating the importance of a precocious untethering surgery.

Methods: We studied retrospectively 66 paediatric patients affected by OSD operated between 1994 and 2006 in the Department of Paediatric Neurosurgery of Children’s Hospital “Regina Margherita” in Turin. 33 male and 33 female, ranging from 1 month to 22 years (mean 3,72 years). 4.6 yrs of follow-up (2 months to 9 yrs). 59 pts were never untethering before: spinal lipoma (34, 57,7%), fatty filum (13, 22%), dermal sinus tract (9, 15.2%), terminal myelocystocele (2, 3,4%) and adhesions/bands (1, 1,7%). The others 7 pts were operated for retethering. We divided the patients in 3 groups (<1 year, 13-36 months and >36 months) and analyzed the neurological evolution considering the dysraphism type.

Results: The mean age of patients without neurological sings at diagnosis was 16,3 months, while if neurological sings were present the average was 62,7 months. Bladder dysfunction was present mainly in older patients (>1 years) and in lipomyelomeningocele. In 9 pts with bladder dysfunction less than 1 year old were presents spinal cord and genito-urinary anomalies. Bladder dysfunction has a poorly chance of improving after surgery in children over 2 years old. Neurological signs, bladder dysfunction and orthopaedic anomalies affected the major part of older patients at diagnosis.

Conclusions: Progressive neurological deterioration with loss of bladder control is the natural history of untreated OSD. Early diagnosis and surgical intervention may prevent significant neurological deterioration and progressive disability. The goal of surgery is to re-establish the normal anatomical plans and obtain the untethering of the spinal cord. Lipomyelomeningocele have poor prognosis in a long time, while fatty filum have high likelihood to improve after surgery and have good prognosis. A long follow-up is mandatory because retethering may appear many years after first surgery. Early surgery may change the natural history of a gradual loss of function obtaining clinical stability.