Split Spinal Cord

Split cord malformations (SCMs) have captured the imagination since the first description in the 17th century. This occult spinal dysraphism is associated clinically with cutaneous, neurological, urologic, and orthopedic abnormalities. SCMs are an embryodysmorphic consequence of anomalous neurenteric fistulization during gastrulation. Varying amounts of bone formation-inducing meninx primitiva invades this fistula, leading to the formation of a bony septum separating two hemicords into separate dural sleeves (type I) or a fibrous septum separating two hemicords within the same dural sleeve (type II). Patients with SCMs overall have excellent functional status, although they are commonly diagnosed in childhood following presentation for back pain, progressive neurological deficits, or urinary symptoms. Surgical goals include releasing the central nervous tissue from any tethering elements, including fibrous or bony septa and fila terminale. Other associated abnormalities, including scoliosis, open dysraphism, dermal sinus tract, and dermoid, may require concurrent or staged surgical therapies. Some disagreement regarding prophylactic surgery exists among authors, although recommendations are unanimous for patients with classic symptoms. Surgical complications include urinary retention, cerebrospinal fluid leak, and wound infection, with low rates of transient or permanent neurological deficits. Patients who have undergone surgery as well as those who have not should be followed long-term for insidious symptoms of back pain and delayed urologic functional decline.