All-pedicle-screw versus hybrid hook-screw instrumentation for posterior spinal correction surgery in adolescent idiopathic scoliosis: a curve flexibility matched-pair study.

INTRODUCTION: Comparisons of all-pedicle-screw (PS) and hybrid hook-screw (HS) instrumentation for the treatment of adolescent idiopathic scoliosis (AIS) have produced conflicting results. The aim of this study was to compare all-pedicle-screw and hybrid hook-screw instrumentation for the treatment of AIS using a matched-pair study design in which preoperative flexibility was matched.
METHODS: In this retrospective study conducted at one medical center, 21 all-pedicle-screw/hybrid hook-screw pairs of Lenke type I AIS patients matched for age, height, weight, body mass index, sex, and preoperative curve flexibility who had been treated at our institution from January 2000 to October 2006 were selected. Postoperative and 2-year postoperative coronal curve correction, postoperative kyphosis, blood transfusion needs, operation time, and hospital cost were measured and analyzed statistically.
RESULTS: The PS group compared with the HS group had better postoperative correction (P = 0.0231) and 2-year coronal curve correction (P = 0.016). While statistically significant (P = 0.0073), the postoperative Cobb angle was only 3° less in the PS group, Maintenance of correction after 2 years was better in the PS group (P = 0.0016). The PS group had less blood loss (P < 0.0001) and shorter operation time (P < 0.0001), but the hospital cost for the PS group was higher (P < 0.0001).
CONCLUSIONS: All-pedicle-screw and hybrid hook-screw instrumentations are comparable with regard to curve correction, but all-pedicle screw instrumentation reduces blood loss during surgery and shortens the operation time, which may help shorten healing time.