Commonest site of meningomyelocele is :

Myelomeningocele can occur at any spinal level but usually is seen between levels T12 and S2. Because neural tissue fails to form properly, the child is paraplegic and insensate below the level of the dysraphism. The clinical determination of neurologic level is most easily accomplished by describing the last muscles contracting under active voluntary motor control. Ref : Rab G.T. (2006). Chapter 11. Pediatric Ohopedic Surgery. In H.B. Skinner (Ed), CURRENT Diagnosis & Treatment in Ohopedics, 4e