Operative treatment of severe scoliosis and pelvic obliquity in patients with spinal muscular atrophy: assessment of outcomes and complications

Abstract

Background: Few reports exist that focus on patients with spinal muscular atrophy (SMA) and severe spinal deformity. In this study, we aimed to report surgical outcomes and complications for SMA patients with severe scoliosis and pelvic obliquity.

Methods: A retrospective review of data on operatively treated SMA patients with severe scoliosis and pelvic obliquity (minimum major coronal curve Cobb angle > 100° and pelvic obliquity > 20°) was performed. Radiography findings, pulmonary function, motor status, the sitting function score, and perioperative and postoperative complications were the main clinical outcomes examined. Muscular dystrophy spine questionnaire (MDSQ) responses and caregiver responses to four anchor questions (quality of life/comfort/ease of care/overall health) using Likert scales were recorded.

Results: Of 28 consecutive patients, 22 (79%) completed the minimum 2-year follow-up (mean age at surgery = 16.1, 68% female). The mean follow-up duration was 40.3-mo. All patients underwent one-stage posterior spinal fusion (PSF) with pelvic fixation. Radiographic measurements (main coronal curve, kyphosis, pelvic obliquity) were significantly corrected (all p < 0.001) and were maintained at the last follow-up. The mean forced vital capacity (FVC) remained stable during follow-up, with 50% of patients showing improvement. The percentage of patients who could sit independently increased significantly from 22.7% preoperatively to 77.3% postoperatively (p < 0.001). The total sitting-related MDSQ score significantly increased from 8.5 to 12.5 at 6 months postoperatively, and to 15.0 at the last follow-up (p < 0.001). Six instances of complications (two instances each of pneumonia, epiglottic edema, and delayed wound healing) occurred perioperatively in six patients (27.3%), but no surgical intervention was required.

Conclusion: Operative treatment significantly improved radiographic parameters and sitting function and maintained pulmonary function without serious complications in SMA patients with severe scoliosis and pelvic obliquity.

Keywords: Clinical outcome; Pelvic fixation; Posterior spinal fixation; Scoliosis; Spinal muscular atrophy.

Fig. 1

Flow chart of study patient selection

Fig. 2

Distribution of the four anchor question answers at 6 months and the last postoperative follow-up. No significant difference was observed across the two time points analyzed

Fig. 3

A 11-year-old female diagnosed with SMA underwent posterior spinal fusion and pelvic fixation by using traditional iliac screws (left side: 7.0 * 65 mm; right side: 7.0 * 40 mm). (A) Preoperative posteroanterior and lateral radiographs of the sitting whole-spine showing severe scoliosis with associated increased kyphosis and pelvic obliquity. (B) This image shows that spinal deformity and pelvic obliquity were corrected at 6-mo postoperatively. Images (C) and (D) show that the corrected spinal deformity and pelvic obliquity were maintained at 18-months and 64-months postoperatively, respectively

Fig. 4

A 12-year-old male diagnosed with SMA underwent posterior spinal fusion and pelvic fixation by using S2-AI screws (both side: 8.0 * 80 mm). (A) Preoperative posteroanterior and lateral radiographs of the sitting whole-spine showing severe scoliosis (main curve cobb angle: 115°) with pelvic obliquity (25°). (B) shows that spinal deformity and pelvic obliquity were corrected at 6-mo postoperatively. (C) and (D) show that the corrected spinal deformity and pelvic obliquity were maintained at 18-months and 42-months postoperatively, respectively