Introduction: Split cord malformations (SCMs) are rare congenital abnormalities arising from a primary neurulation defect during embryological development of the spinal cord. SCMs can lead to progressively worsening scoliosis and gait difficulties if left untreated. Traditionally, SCMs have been classified into two categories determined by the presence of a dural sac around each hemi-cord separated by a rigid septum (Type 1) or a single dural sac surrounding both hemi-cords separated by non-rigid tissues (Type 2). This case is the only known example of a SCM with a single dural sheath, separated by a bony spicule in an adult.
Methods: We reviewed the clinical data and imaging from the index case and conducted a systematic review of the medical literature using PUBMED and multiple combinations of keywords. Associated signs among patients with SCMs were researched. Classification systems to accurately describe patients sharing characteristics of both Type 1 and 2 SCMs were explored.
Results: The most inclusive classification system of SCMs found by our methods divides Type 1 SCMs into four categories based on the presence of a dividing bony spur and the location of the duplicated spinal cord in relation to it. Given this classification system, our patient can be classified as Type 1b SCM, making him the only known adult to have this pathology. The most common sign associated with SCMs is hypertrichosis in up to 79% of patients. Furthermore, up to 31% of patients with scoliosis also have intraspinal abnormalities, with approximately 14% of these patients exhibiting a SCM.
Conclusions: As illustrated in the literature and our patient, prophylactic laminectomy to remove the septum causing a SCM could have prevented or minimized resultant scoliosis and neurologic sequelae. Given these findings, screening for SCM is recommended when congenital scoliosis or hypertrichosis is discovered in young patients.
Patient Care: Having a knowledge of common associations found with Split Cord Malformations allows practitioners to more effectively screen patients for intra-spinal abnormalities. If a split cord malformation is found, prompt surgical treatment can help prevent resulting neurologic sequelae.
Learning Objectives: 1. Consider screening for a split cord malformation when patients present with scoliosis or other associated signs such as hypertrichosis.
2. Identify different types of split cord malformations based on imaging and intra-operative findings.
3. Describe the potential long term sequelae of untreated split cord malformations.