Surgical outcomes and complications of posterior hemivertebra resection in children younger than 5 years old

Abstract

Background: There have been many reports on posterior hemivertebra resection. However, there were few articles in very young cases. This is a clinical retrospective study to evaluate the complications and efficacy of posterior hemivertebra resection in very young cases.

Methods: From January 2003 to January 2012, 39 consecutive cases of congenital scoliosis with hemivertebra were retrospectively investigated in our hospital, including 18 females and 21 males, aged from 21 to 65 months old (average 42.4 months). All the cases underwent posterior hemivertebra resection with transpedicular instrumentation. Clinical charts and radiographs of spine were retrospectively reviewed to record complications and outcomes postoperatively and at the latest follow-up.

Results: Mean operation time was 186.4 min (90-280 min) with average blood loss of 306.6 (100-700) ml. The total number of hemivertebrae resected was 43, including one hemivertebra in 35 cases and two hemivertebrae in 4 cases. The mean number of fused segments was 3.4, including 22 cases (56.4 %) with bisegmental fusion and 4 cases with mesh cage. Average follow-up period was 5.4 (3 to 11) years. There was a mean improvement rate of 83.6 % in the segmental scoliosis from 38.4° before surgery to 6.3° after operation and a mean improvement rate of 81.9 % in segmental kyphosis from 17.1° to 3.2° over the same time. The spontaneous correction rates of the compensatory cranial curve and compensatory caudal curve were 65.7 and 66.9 %, respectively. There were three complications (two cases),one pedicle fractures, one rod breakages, and one additional surgery for curve progression. Besides these, two additional surgeries (two cases) were performed to remove the instrumentation for pedicle elongation in the follow-up. There was no neurological complication.

Conclusions: Posterior hemivertebra resection with transpedicular instrumentation is a safe and effective procedure in very young congenital scoliosis cases. Earlier surgeries can achieve short fusion and save more mobile segments. However, complications associated with implants and spinal growth still remain major concerns.

Keywords: Complication; Congenital scoliosis; Hemivertebra resection; Posterior surgery; Surgical outcome.

Fig. 1

An infant with congenital scoliosis. Preoperative radiographs (a, b) and CT 3D reconstruction (c, d) showed fully segmented hemivertebra of T12/L1 and semi-segmented hemivertebra of L4/L5 with coronal segmental scoliosis of 40° and 32° and segmental kyphosis of 32°. Post-operational radiographs (e, f) showed T12/L1 and L4/L5 hemivertebra resection and internal fixation, and the scoliosis decreased to 5° and 2°, and the kyphosis decreased to 11°. Radiographs at 4-year follow-up (g, h) showed good spinal balance with coronal segmental scoliosis of 9° and 2° and segmental kyphosis of 5°

Fig. 2

An infant with congenital scoliosis. Preoperative radiographs (a, b) showed fully segmented hemivertebra of L5/6 with the Cobb angle of 27°. Postoperative radiographs (c, d) showed excellent correction by L5/6 hemivertebra resection with the Cobb angle of 2°. Radiographs at 3 years follow-up (e, f) showed excellent correction with the Cobb angle of 4°. CT scan (i, j) showed solid fusion at the fused segments and L5 right pedicle screw dislodgement. And implants were removed (g, h)