Related Experiment Video
Updated: Sep 11, 2025
Adjustable Stiffness, External Fixator for the Rat Femur Osteotomy and Segmental Bone Defect Models
Published on: October 9, 2014
Effect of remodeling on correction of tibia vara using the circular hexapod external fixator
Sherif Galal1, Ahmed O Sabry2, Al-Munqith Al-Abri3
1Department of Orthopaedic Surgery, Khoula Hospital, Ministry of Health, Muscat, Oman; Department of Orthopaedic Surgery, Kasr Al-Ainy Faculty of Medicine, Cairo University, Cairo, Egypt.
Background:
We aimed to evaluate if there would be loss of some correction achieved (caused by remodeling) after correcting tibia vara deformity with hexapod circular fixators and if that loss of correction would influence clinical outcomes.
Hypothesis:
The hypothesis of the study was that remodeling at the osteotomy site would lead to loss of some correction over time.
Patients And Methods:
This retrospective study included 18 patients with tibial varus deformity as a sequela of adolescent tibia vara who underwent proximal tibial deformity correction using the Hexapod External Fixator between August 2020 and August 2023. We assessed clinical outcomes using the Limb Deformity-Scoliosis Research Society (LD-SRS) score and radiographic parameters such as Mechanical Axis Deviation (MAD) and Mechanical Axis Angle (MAA) measured preoperatively, post-correction, and at the final follow-up. Statistical analyses were performed to quantify the statistical significance of limb alignment change at final follow-up and to attempt to define a cut-off angle to be achieved at the end of correction that would result in no deviation in limb alignment in the long run.
Results:
After a mean follow-up duration of 18.7 mo, there was a significant improvement in both functional and radiographic measures. The mean LD-SRS score improved from 3.4 ± 0.5 preoperatively to 4.6 ± 0.4 at the final follow-up. Radiographic parameters showed notable correction, with the mean MAA improving from 25.1º ± 8.7 (varus alignment) preoperatively to 1.7º ± 2.5 (valgus alignment) at the end of correction, and to 2.4º ± 3.3 (varus alignment) at the final follow-up. Similarly, the mean MAD value improved from 87.4 ± 29.5 mm (medial deviation) preoperatively to 7.3 ± 9.6 mm (medial deviation) at the end of correction, and to 6.1 ± 11.5 mm (lateral deviation) at the final follow-up.
Discussion:
When treating adolescents with tibia vara deformity using hexapod fixators, it is advisable to over correct the MAA by 5° (valgus overcorrection) and the MAD by 7-9 mm to counteract the loss of some correction over time caused by the effect of remodeling.
Level Of Evidence:
III; retrospective study.
More Related Videos
07:35Creating Rigidly Stabilized Fractures for Assessing Intramembranous Ossification, Distraction Osteogenesis, or Healing of Critical Sized Defects
Published on: April 11, 2012
08:20A Reliable and Reproducible Critical-Sized Segmental Femoral Defect Model in Rats Stabilized with a Custom External Fixator
Published on: March 24, 2019
Related Concept Videos
01:27Fractures: Bone Repair
Minor fractures with no bone displacement are treated by immobilizing the fractured bone using a cast or splint. However, in the case of fractures with displaced bones, the broken bones are repositioned before immobilization to ensure successful healing without deformation and loss of function. The realignment of fractured bone ends is performed through a process called reduction. If the...
01:40Bone Remodeling