Occult spinal dysraphism involves a wide range of congenital anomalies, e.g., lipoma, Lipomeningomyelocele, congenital dermal sinus, etc. Occult spinal dysraphism also may present with a wide spectrum of clinical manifestations and radiological findings, i.e., it ranges from asymptomatic patients that are accidentally discovered to low lying conus with neurological, skeletal and urological manifestations. Even though neurosurgeons are well-aware of neurological presentations that indicate surgical intervention in children with occult spinal dysraphism, urological symptoms may present some controversy in management. This review aims to discuss urological outcomes of detethering as regarding time of intervention, improvement of the urological symptoms after detethering, and the role of urodynamics preoperatively and during follow-up.
An online search of the literature was done including studies in English language from 1990 to January 2022. Included studies were analytical with well conducted descriptive nature of acceptable quality (at least level 3 evidence). Patient characteristics included both male and female children and adolescents, up to 19 years old who presented with clinical and/or radiological evidence of tethering of the spinal cord. Most studies that were included had availability of urodynamics. A total of 15 studies were included involving 633 patients. Meningomyelocele (MMC) and other spina bifida operta cases are excluded.
Results of all studies were collected and mean age of studies was gathered and plotted on a chart in relation to urological outcome and urodynamic improvement. Most results favored early detethering; however, many factors were found to affect the inverse proportion curve of age with clinical improvement or urodynamics. For example, studies that included secondary tethered cord showed poorer results than results that included primary tethered cord only, preoperative severity of urological symptoms (more severe symptoms were associated with irreversible poor outcomes), and preoperative urodynamic parameters.
The management of tethered cord syndrome and occult spinal dysraphism remains controversial. There is lack of class 1 evidence regarding tethered cord release surgery in occult spinal dysraphism. Heterogenicity of pathology, symptomatology and radiology make the randomization of such sample size difficult. The outcomes of surgical detethering are therefore multifactorial. A large sample of prospective randomized controlled studies addressing each factor, e.g., age, severity of symptoms, preoperative urodynamic parameters, is recommended in order to evaluate the impact of each factor on outcome.