Pedicle screw versus hybrid posterior instrumentation for dystrophic neurofibromatosis scoliosis

Abstract

Surgical management of severe rigid dystrophic neurofibromatosis (NF) scoliosis is technically demanding and produces varying results. In the current study, we reviewed 9 patients who were treated with combined anterior and posterior fusion using different types of instrumentation (i.e., pedicle screw, hybrid, and all-hook constructs) at our institute.Between September 2001 and July 2010 at our institute, 9 patients received anterior release/fusion and posterior fusion with different types of instrumentation, including a pedicle screw construct (n = 5), a hybrid construct (n = 3), and an all-hook construct (n = 1). We compared the pedicle screw group with the hybrid group to analyze differences in preoperative curve angle, immediate postoperative curve reduction, and latest follow-up curve angle.The mean follow-up period was 9.5 ± 2.9 years. The average age at surgery was 10.3 ± 3.9 years. The average preoperative scoliosis curve was 61.3 ± 13.8°, and the average preoperative kyphosis curve was 39.8 ± 19.7°. The average postoperative scoliosis and kyphosis curves were 29.7 ± 10.7° and 21.0 ± 13.5°, respectively. The most recent follow-up scoliosis and kyphosis curves were 43.4 ± 17.3° and 29.4 ± 18.9°, respectively. There was no significant difference in the correction angle (either coronal or sagittal), and there was no significant difference in the loss of sagittal correction between the pedicle screw construct group and the hybrid construct group. However, the patients who received pedicle screw constructs had significantly less loss of coronal correction (P < .05). Two patients with posterior instrumentation, one with an all-hook construct and the other with a hybrid construct, required surgical revision because of progression of deformity.It is difficult to intraoperatively correct dystrophic deformity and to maintain this correction after surgery. Combined anterior release/fusion and posterior fusion using either a pedicle screw construct or a hybrid construct provide similar curve corrections both sagittally and coronally. After long-term follow-up, sagittal correction was maintained with both constructs. However, patients treated with posterior instrumentation using pedicle screw constructs had significantly less loss of coronal correction.

Combined Anterior-Posterior Versus Posterior-only Spinal Fusion in Treating Dystrophic Neurofibromatosis Scoliosis With Modern Instrumentation

“…13,22,23,27,34 Moreover, the use of APSF is still recommended when treating children under the age of 10 years because single PSF may cause the crankshaft phenomenon because of persistent anteriorcolumn growth. 3,9,30 Several studies have reported that the placement of pedicle screws could reduce the risk of the crankshaft, but further research is needed to verify this claim. 45,46 Several limitations of the meta-analysis should be mentioned.…”

“…Hence, a total of 16 studies were finally selected into the meta-analysis. 9,[22][23][24][25][26][27][29][30][31][32][33][34][35][36][37] The flow diagram is shown in Figure 1.…”

Management and surgical outcomes of dystrophic scoliosis in neurofibromatosis type 1: a systematic review

“…Wang et al suggested that pedicle screw constructs have less loss of coronal correction at long-term follow-up compared with hybrid constructs. 56 Pedicle morphology often dictates the fixation technique, and in many circumstances, severely dysplastic pedicles may not be appropriate for pedicle screws. 44 As expected, pedicle dysplasia results in high rates of malpositioned screws, with one study reporting an incidence of 30.5% (9.9% medial and 20.6% lateral) with the freehand insertion technique.…”

Comparison of combined anterior–posterior approach versus posterior-only approach in neuromuscular scoliosis: a systematic review and meta-analysis

“…As for the opposite idea of several studies [11,12,18,22,25], the advantage in our meta-analysis was that the data were divided into two subgroups according to the significant difference of the preoperative Cobb angle to eliminate the influence.…”

“…Zhou et al [11] indicated, through APA, the mean preoperative scoliosis of 105.1° was corrected to 27.5° at the most recent follow-up, and the correction rate of lumbar curves was up to 82.1%. Wang et al [12] indicated APA decreased the loss of angle between postoperation and follow-up and maintained curve corrections in both coronal and sagittal planes. Jasiewicz et al [13] indicated APA treatment of severe scoliosis enables stable correction with some improvement of spinal balance in both the coronal and sagittal planes.…”