SURGICAL TREATMENT OF PARALYTIC SCOLIOSIS IN PATIENTS WITH MYELOMENINGOCELE

Abstract

Introduction and Objectives: This is a retrospective clinical and radiographic study of 19 patients affected by paralytic scoliosis secondary to myelomeningocele who were treated surgically with double anterior fusion (without anterior instrumentation) and instrumented posterior fusion from T2 to the sacrum.

Materials and Methods: The study involved 19 patients with scoliosis secondary to myelomeningocele treated surgically by instrumented posterior fusion (3 cases) or double anterior fusion (non-instrumented) with instrumented posterior fusion from T2 to the sacrum (10 cases). Instrumentation consisted of two rods shaped in physiologic kyphosis and lordosis, sublaminar wiring, and anchoring to the pelvis using the classic Galveston technique (7 patients); two rods fixed to the spine by means of sublaminar wires and pedicle screws on the convexity of the curve in the lumbar region and an iliac screw in the pelvis (11 cases); and in one case, anchoring to the pelvis was achieved using an iliosacral screw.

Results: Age of the patients ranged from 9 to 16 years, with a mean of 12 years. There were 11 females and 8 males. Maximum time of patient review was 9 years, and minimum time was 2 years. The level of spinal cord involvement was thoracic in 1 case, upper lumber (L1–L2) in 6 cases, mid-lumbar (L3) in 7 cases, and lower lumber (L3–L4) in 5 cases. Curve patterns were thoracolumbar (apex at T12–L1) in 14 cases and lumbar in 5 cases. Pre-operative curve angles ranged from 60° to 133° with a mean of 93°. Postoperative curve ranged from 15° to 60° with a mean of 42°. There were 6 patients with thoracolumbar kyphosis ranging from 24° to 92° (mean 49°) and 15 patients with pelvic obliquity ranging from 14° to 42° (mean 28°). Decompensation of the trunk with respect to the pelvis ranged from 26 to 0 cm, and postoperatively ranged from 13 to 0 cm (mean 5.5 cm). Of the 19 patients, 9 (50%) experienced complications. One patient presented with non-union and a subsequent delayed infection requiring four operations and removal of material. There were 3 patients that experienced postoperative infections requiring surgical drainage, with 2 cases of leakage of CSF, which resolved with postural therapy. In 5 cases, there was necrosis of the vertex of the triradiate incision, and in one case there was failure of the iliac screw in the pelvis with no clinical consequences.

Discussion and Conclusions: The use of a triradiate incision avoiding a direct approach to the sacral dura, a double anterior and posterior approach in cases of rigid curve (radiographic examination in traction) and saggital deformities (thoracolumbar kyphosis), and the use of pedicle screws in the distal vertebrae and in the iliac wing allow the correction of frontal and sagital deformities and pelvic obliquity in patients with myelomeningocele.