Biomechanical characteristics of distal tibial articular surface defect of the ankle joint:three-dimensional finite element analysis

Song Zuo-cheng; Yan Xiao-long

doi:10.3969/j.issn.2095-4344.2016.48.010

Abstract：BACKGROUND:Studies found that three-dimensional finite element analysis can be used in the study of ankle biomechanics, but research on distal tibial articular surface defect was few. <br> OBJECTIVE:To analyze the biomechanics of distal tibial articular surface defect with three-dimensional finite element, and provide the basis for mechanism of ankle injury related diseases. <br> METHODS:We established ankle three-dimensional finite element model, and set different diameters of distal tibial articular surface defect, observed the peak stress of distal tibial articular surface at load of 1 400 N and the flexor of 14°, at load of 700 N and neutral position, at load 2 100 N and dorsiflexion of 10°, and contact area of tibial astragaloid joint surface at different postures and different defect diameters. <br> RESULTS AND CONCLUSION:(1) At load of 1 400 N and plantar flexion of 14°, the distal tibial articular surface front quadrant stress peak was smal est when the distal tibial articular surface defect diameter was 8 mm, and was maximum when defect diameter was 16 mm;the distal tibial articular surface front inner quadrant stress peak was smal est when the distal tibial articular surface defect diameter was 12 mm, and maximum when defect diameter was 16 mm;the distal tibial articular surface posterior quadrant stress peak was smal est when defect diameter was 12 mm, distal tibial articular surface posterior inner quadrant stress peak was smal est when defect diameter was 0 mm;the distal tibial exterior stress peak was <br> maximum when defect diameter was 16 mm. (2) At load of 700 N and neutral position, exterior front quadrant, front inner quadrant, posterior quadrant and posterior inner quadrant stress peaks increased with the distal tibial articular surface defect increases;the distal tibial articular surface defect stress peak was maximum when defect diameter was 16 mm. (3) At load of 2 100 N and dorsiflexion of 10°, the distal tibial articular surface stress peak was maximum when defect diameter was 16 mm. (4) Results showed that distal tibial articular surface defect diameter was not exceeding 12 mm, and has little effect on the function of the ankle joint;defect diameter exceeding 12 mm has great effect on the ankle function.