The MOMS (Management of Myelomeningocele Study) trial demonstrated the value of in-utero repair for open neural tube defects. Ventriculoperitoneal shunt rates were reduced, the hindbrain herniation improved, and the motor exams of the lower extremities were better than predicted historical data. Surgical techniques include opening the uterus and presenting the spinal defect into the operative field for repair. Another technique utilizes well-placed trocars into the uterus to repair the defect in the baby using laparoscopic instruments. The in-utero repair usually occurs around 24-26 weeks of gestational age. We utilize a commercially available cryopreserved human umbilical cord patch to repair the dural defect and in some instances use this same ‘patch’ to repair the skin.

The patients return at one year post-surgery for an MRI study of the brain and spine, undergo a thorough examination of the extremities with attention to motor power rating, and sensory mapping of the lumbosacral plexus including the perianal and genital regions.

The vast majority of patients have a profound ‘saddle anesthesia’ with virtually no response to sharp testing. The anal reflex response is usually absent when saddle anesthesia is present. The motor exams are variable but most patients have at least an L4 or better motor exam. Two of 52 patients to date have had a normal sensory exam.

Initial sensory mapping, even with age-related exam limitations, provides data as these patients are followed in life. With growth, loss of motor function and changes in sensation as well as documented urodynamic studies may be important indicators of tethered cord and potential surgery for that entity.