Generally, the skeleton is very stiff in patients with severe Lenke type 1 adolescent idiopathic scoliosis (AIS). Traditional surgical treatment consists of anterior release and posterior fusion to improve the coronal correction and fusion rate. Unfortunately, they are always followed by relatively high incidence of complications.OBJECTIVE:
To compare the clinical outcomes of anterior-posterior spinal fusion (APSF) versus posterior spinal fusion (PSF) alone for patients with severe (Cobb angle between 75° and 100°) Lenke type 1 AIS.DESIGN, TIME AND SETTING:
Retrospective case analysis. The patients were selected from Department of Orthopedics, Changhai Hospital of Second Military Medical University of Chinese PLA between June 1998 and June 2005.PARTICIPANTS:
126 patients with severe Lenke type 1 AIS, who underwent spinal fusion (APSF or PSF) at Department of Orthopedics, Changhai Hospital of Second Military Medical University of Chinese PLA were included for analysis, including 99 females and 27 males, aged 10-18 years.METHODS:
All patients were divided into 2 groups. In APSF group (n=32), anterior release and posterior hooks were used; in PSF group (n=94), posterior approach operation alone was performed, of which, 18 cases underwent hook alone, 22 underwent hybrid constructs of proximal hooks and distal pedicle screws, and 54 underwent pedicle screw alone. The patients were followed up for average of 3.5 years. Imaging measures and SRS follow-up form were used to evaluate results. The primary and secondary statistical analyses were analyzed using Wilcoxon-Mann-Whitney tests and the Kruskal-Wallis test.MAIN OUTCOME MEASURES:
Lateral curve angle, lateral bending angle and T5˜12 posterior convex angle.RESULTS:
There were no statistically significant differences between two groups in terms of gender, age, number of levels fused, Cobb angle measurement of preoperative coronal or sagittal thoracic curve magnitude. The APSF group, when compared with the PSF group, had greater final overall correction of the coronal curve (P=0.007 5). There were no significant differences in the sagittal alignment from T5-12 or the SRS outcomes data between two groups. Pedicle screw alone corrected the coronal Cobb measurements more than hook alone and hybrid constructs of proximal hooks and distal pedicle screws (P=0.012 0), but similar to the APSF group in coronal correction (P=0.952 4). There were no reoperations due to implant failure/pseudarthroses for any of the patients.CONCLUSION:
APSF of Lenke type 1 severe AIS allows greater coronal correction of thoracic curves when compared with PSF alone using thoracic hook constructs or hybrid constructs. However, the posterior approach of thoracic pedicle screw techniques could achieve the same effect and avoid the anterior release and related complications, which is safe and simple.