Effect of articular step-off on knee joint contact pressures in fractures of the medial tibiul plateau / 中华创伤骨科杂志

ABSTRACT

Objective To study the effect of articular step-off on knee joint contact pressures in fractures of the medial tibial plateau. Methods Eight specimens of embalmed adult knee joint were used to establish models of articular step-off of the medial tibial plateau by 0,1,2,3 mm respectively (Schatzker Ⅳ fracture) .The technique of pressure sensitive film was used to measure the contact pressures on the weight-bearing area of the knee joint in the 3 models. Results When the step-offs of medial tibial plateau were 0,1,2,3 mm,the average contact pressures on the lateral compartment were respectively 3.34 ± 0.06 MPa,3.48 ± 0.06 MPa,4.19 ± 0.05 MPa,4.19 ± 0.04 MPa,while the average contact pressures on the medial coMPartment were 4.04±0.17 MPa,4.57±0.20 MPa,5.64±0.20 MPa,5.64±0.19 MPa.When the step-off of medial tibial plateau was 2 mm,the average contact pressures on the medial and lateral plateaus increased by 39.6％ and 25.4％ compared with the 0 mm step-off,with statistically significant differences (P ＜0.05). Conclusions If the step-off of the medial tibial plateau reaches ≥ 2mm,open reduction and internal fixation should be indicated to prevent secondary traumatic arthritis.When the step-off of the medial tibial plateau is ＜ 2 mm,conservative treatment can be a proper choice.