ABSTRACT
Objective To investigate the effect of Kirschner and bandage fixation on the hallux valgus (HV) after distal osteotomy of the first metatarsus. Methods A comprehensive three-dimensional finite-element model of the foot was established based on medical images of the foot of a patient with HV, including bones, sesamoid, cartilage, ligaments, soft tissues, and Achilles tendon. The models of Kirschner and bandage fixation were also established to investigate the biomechanical behavior of the foot with HV during full weight-bearing standing. Results The compressive stress (14.9 MPa) between the osteotomy fragment surfaces in bandage fixation was higher than the peak stress of the Kirschner needle (6.71 MPa). The Kirschner fixation was better than the bandage fixation from the dorsal, plantar, medial, and lateral foot. Therefore, it was more favorable for the stability of the osteotomy. Conclusions The bandage fixation can reduce the healing time of osteotomy, providing an optimal design for fixation methods after hallux valgus operations.
ABSTRACT
Hallux valgus (HV) was one of the most frequent female foot deformities. The aim of this study was to evaluate mechanical responses and stabilities of the Kirschner, bandage and fiberglass fixations after the distal metatarsal osteotomy in HV treatment. Surface traction of different forefoot regions in bandage fixation and the biomechanical behavior of fiberglass bandage material were measured by a pressure sensor device and a mechanical testing, respectively. A three-dimensional foot finite element (FE) model was developed to simulate the three fixation methods (Kirschner, bandage and fiberglass fixations) in weight bearing. The model included 28 bones, sesamoids, ligaments, plantar fascia, cartilages and soft tissue. The peak Von Mises stress (MS) and compression stress (CS) of the distal fragment were predicted from the three fixation methods: Kirschner fixation (MS=6.71MPa, CS=1.232MPa); Bandage fixation (MS=14.90MPa, CS=9.642MPa); Fiberglass fixation (MS=15.83MPa, CS=19.70MPa). Compared with the Kirschner and bandage fixation, the fiberglass fixation reduced the relative movement of osteotomy fragments and obtained the maximum CS. We concluded that fiberglass fixation in HV treatment was helpful to the bone healing of distal fragment. The findings were expected to guide further therapeutic planning of HV patient.
