Comperative analysis of segmental pedicle screw and hybrid instrumentation techniques in the treatment of lenke type 1 adolescent idiopathic scoliosis

2.SUMMARYComperative Analysis of Segmental Pedicle Screw and Hybrid InstrumentationTechniques in the Treatment of Lenke Type 1 Adolescent Idiopathic ScoliosisUlaş SERARSLAN, MDDokuz Eylul University Medical FacultyDepartment of Orthopaedics and TraumatologyIzmir-TURKEYThe most recent instrumentation innovation for the treatment of adolescent idiopathicscoliosis (AIS) is pedicle screw. n the previous studies, the all screw constructs wereshown to be superior to all hook constructs. There are only two studies in the literature thatcompare hybrid constructs (lumbar pedicle screws and thoracic hooks) and all screwconstructs. These studies showed different results. The subject that which technique isbetter, remains controversial. For this reason, we decided to compare the effectiveness oftwo different techniques, on the postoperative curve correction.Fifty two AIS patients with Lenke type 1 curves, who underwent isolated posteriorspinal instrumentation and fusion were analyzed. Twenty six patients underwent fusionusing segmental pedicle screw fixation and 26 patients underwent fusion using hybridconstructs. Preoperative and early postoperative (within 2 months postoperatively)radiographic measurements were compared .In the screw group mean thoracic Cobb angle decreased from 57,3° to 9,2°, in thehybrid group mean thoracic Cobb angle decreased from 51° to 13,4° postoperatively. Themean major curve correction was 83% in the screw group and 73% in the hybrid group.The major curve correction was significantly better in the screw group (P=0,016). Therewas no significant difference observed between two groups when lomber curve correction,sagital plane change, apical vertebral translation change and coronal balance correctionwere compared.In conclusion, the major curve correction with posterior segmental pedicle screwfixation in Lenke type 1 AIS curves is superior to that maintained with hybrid constructs.Key words: Adolescent idiopathic scoliosis, Lenke classification, segmental pediclescrew, hybrid instrumentation.