Accuracy of the hexapod external fixator in treating tibial angular deformities with or without limb length discrepancy: a retrospective study


Danışman M., YILMAZ E. T., Özdemir E., TUNCAY O., YILMAZ G.

Journal of Pediatric Orthopaedics Part B, vol.32, no.6, pp.611-616, 2023 (SCI-Expanded, Scopus) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 32 Issue: 6
  • Publication Date: 2023
  • Doi Number: 10.1097/bpb.0000000000001101
  • Journal Name: Journal of Pediatric Orthopaedics Part B
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, CINAHL, MEDLINE
  • Page Numbers: pp.611-616
  • Keywords: deformity correction, hexapod external fixator, limb length discrepancy, limb lengthening, tibia deformity
  • Hacettepe University Affiliated: Yes

Abstract

Objective Hexapod external fixator systems allow simultaneous deformity correction in multiple planes as well as limb lengthening. The aim of this study is to evaluate the accuracy of a hexapod frame (smart correction frame) in different types of tibial deformities requiring correction with or without lengthening. Methods A total of 54 tibial angular deformities and limb length discrepancies operated with a hexapod frame between January 2015 and January 2021 were classified into four groups: “Group A (n = 13): only lengthening,” “Group B (n = 14): lengthening and uniplanar correction,” “Group C (n = 16): only uniplanar correction,” and “Group D (n = 11): biplanar correction.” The accuracy of angular deformity correction/lengthening was calculated by dividing the actual correction/lengthening achieved after frame removal by the preoperative planned lengthening/ correction. Results The lengthening accuracy in Group A and Group B was 96.3 ± 7.1% and 95.7 ± 5.9%, respectively (P = 0.685). The angular deformity correction accuracy was 85.1 ± 9.9% for Group B, 85.2 ± 13.9% for Group C, and 80.2 ± 18.4% for Group D (P = 0.852). A revision program was performed in six cases (1 in Group B, 1 in Group C, and 4 in Group D) for full correction of the deformities. Conclusion The accuracy of tibial lengthening is high with the hexapod frame and is minimally affected by simultaneous deformity correction; however, the accuracy of angular correction slightly reduces as the deformity becomes more complex. Surgeons should be aware that reprogramming may be required after complex deformity correction. J Pediatr Orthop B 32: 611–616 Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.