Guided growth with the tension band plate construct: a prospective comparison of 2 methods of implant placement.

INTRODUCTION: Since its introduction in 2007, the use of 8-plates has gained great popularity for the correction of diverse deformities in skeletally immature patients. In this study, we evaluate 2 different techniques of implant placement. METHODS: A consecutive series of patients with indication of guided growth around the knee (femur or tibia) were included in the study. Patients were randomly divided in 2 groups, with 8-plate inserted using technique as described by Stevens (group A) versus technique modified from Paley (group B). We analyzed operative time, radiation exposure, incision size, and intraoperative complications. Comparisons between groups were performed with a Mann-Whitney test. A 2-tailed P-value <0.05 was considered significant. RESULTS: We evaluated a total of 31 procedures in 18 patients (16 in group A and 15 in group B). Age and sex was similar in both groups (P=0.470 and 0.720). Operative time and radiation exposure was significantly lower in group B: 20 minutes (range, 11.37 to 29.30 min) versus 13.09 minutes (range, 9.31 to 25 min) (P 0.009), and 0.30 µGy (range, 0.10 to 1.30 µGy) versus 0.10 µGy (range, 0.00 to 0.70 µGy) (P=0.013), respectively. The incision size was also smaller in group B: 27 mm (range, 23 to 29 mm) versus 23 mm (range, 18 to 24 mm) (P=0.05). There were no intraoperative complications in any of the 2 groups. CONCLUSIONS: Modified technique for 8-plate placement seems to reduce operative time, radiation exposure, and incision size for guided growth around the knee. STUDY DESIGN: Level of evidence II-prospective randomized study.