TY - JOUR
T1 - Computed tomography evaluation of rotation correction in adolescent idiopathic scoliosis
T2 - A comparison of an all pedicle screw construct versus a hook-rod system
AU - Asghar, Jahangir
AU - Samdani, Amer F.
AU - Pahys, Joshua M.
AU - D'Andrea, Linda P.
AU - Guille, James T.
AU - Clements, David H.
AU - Betz, Randal R.
PY - 2009/4/15
Y1 - 2009/4/15
N2 - STUDY DESIGN.: Retrospective review with historical cohort. OBJECTIVE.: Our study measures axial rotation of the apical vertebral bodies of patients with adolescent idiopathic scoliosis treated with an all pedicle screw (APS) construct versus a hook-rod (HR) construct using computed tomography (CT). SUMMARY OF BACKGROUND DATA.: Ecker et al (Spine 1988;13:1141-4) observed a 22% derotation of the apical vertebrate of the thoracic spine and 33% of the apical vertebra of the lumbar spine when using an HR system (CD instrumentation). More recently Lee et al (Spine 2004;29:343-9) reported 42.5% derotation of the apical vertebra (both thoracic and lumbar) in a series of APS constructs. Currently, there is no comparison series reported between the 2 types of constructs. METHODS.: From a database of 193 patients with adolescent idiopathic scoliosis and posterior spinal fusions, 32 patients were identified as having all APS constructs with pre- and postoperative CT scans. This cohort of patients was compared with a historical published cohort of patients treated with HR constructs by Ecker et al (Spine 1988;13:1141-4) Comparison of the groups showed no statistically significant differences for age and preoperative Cobb angle of the main curve (P > 0.05); however, there was a statistically significant difference (P < 0.05) in postoperative correction values. The apical vertebral rotation for the major curve was measured from the pre- and postoperative axial CT using the methods described by Aaro and Dahlborn (Spine 1981;6:460-7). RESULT.: The average preoperative rotation was similar between the 2 groups (thoracic: HR = 22.6, APS = 21.3, P = 0.6; lumbar: HR = 19.4, APS = 20.6, P = 0.7). The postoperative correction had a significant difference (thoracic: HR = 16, APS = 8.5, P = 0.015; lumbar: HR = 13.4, APS = 7.0, P = 0.032). The percent correction of the apical vertebrae showed a significant difference, with 22% correction in the HR group and 60% in APS group (P < 0.001). CONCLUSION.: Our study finds axial rotation correction using APSs and a direct vertebral body derotation technique was significantly greater than that obtained with the HR construct.
AB - STUDY DESIGN.: Retrospective review with historical cohort. OBJECTIVE.: Our study measures axial rotation of the apical vertebral bodies of patients with adolescent idiopathic scoliosis treated with an all pedicle screw (APS) construct versus a hook-rod (HR) construct using computed tomography (CT). SUMMARY OF BACKGROUND DATA.: Ecker et al (Spine 1988;13:1141-4) observed a 22% derotation of the apical vertebrate of the thoracic spine and 33% of the apical vertebra of the lumbar spine when using an HR system (CD instrumentation). More recently Lee et al (Spine 2004;29:343-9) reported 42.5% derotation of the apical vertebra (both thoracic and lumbar) in a series of APS constructs. Currently, there is no comparison series reported between the 2 types of constructs. METHODS.: From a database of 193 patients with adolescent idiopathic scoliosis and posterior spinal fusions, 32 patients were identified as having all APS constructs with pre- and postoperative CT scans. This cohort of patients was compared with a historical published cohort of patients treated with HR constructs by Ecker et al (Spine 1988;13:1141-4) Comparison of the groups showed no statistically significant differences for age and preoperative Cobb angle of the main curve (P > 0.05); however, there was a statistically significant difference (P < 0.05) in postoperative correction values. The apical vertebral rotation for the major curve was measured from the pre- and postoperative axial CT using the methods described by Aaro and Dahlborn (Spine 1981;6:460-7). RESULT.: The average preoperative rotation was similar between the 2 groups (thoracic: HR = 22.6, APS = 21.3, P = 0.6; lumbar: HR = 19.4, APS = 20.6, P = 0.7). The postoperative correction had a significant difference (thoracic: HR = 16, APS = 8.5, P = 0.015; lumbar: HR = 13.4, APS = 7.0, P = 0.032). The percent correction of the apical vertebrae showed a significant difference, with 22% correction in the HR group and 60% in APS group (P < 0.001). CONCLUSION.: Our study finds axial rotation correction using APSs and a direct vertebral body derotation technique was significantly greater than that obtained with the HR construct.
KW - Adolescent idiopathic scoliosis
KW - Axial rotation
KW - Vertebral body derotation
UR - http://www.scopus.com/inward/record.url?scp=67650288186&partnerID=8YFLogxK
U2 - 10.1097/BRS.0b013e3181996c1b
DO - 10.1097/BRS.0b013e3181996c1b
M3 - Article
C2 - 19365248
AN - SCOPUS:67650288186
SN - 0362-2436
VL - 34
SP - 804
EP - 807
JO - Spine
JF - Spine
IS - 8
ER -