Effects Of Elbow Collateral Ligament Injury Pattern On Elbow Stability

ObjectivesElbow stiffness is a common complication of traumatic elbow injury.In order to achieve maximum improvement of elbow function,it is necessary not only to remove the peripheral heterotopic ossification but also to release the medial and lateral collateral ligament of elbow.In order to maximize the release of the medial and lateral collateral ligaments without affecting the stability of the elbow,this study investigated the effect of the medial and lateral collateral ligament injury mode on the stability of the elbow by biomechanical experiments.This study provides a safe and effective solution for level and manner of ligament release in dysfunction elbow.MethodsThe 18 formalin-soaked elbow specimens were removed tissues such as skin and muscles,and the ligaments on both sides were retained.The specimens were divided into six groups,transecting lower middle LUCL(group A),transecting lower middle RCL(group B).transecting upper middle LUCL(C group),transecting upper middle RCL(D group),transecting lower middle AMCL(group E),transecting upper middle AMCL(group F),Subsequently,transecting lower middle LUCL and RCL(Group G),transecting upper middle LUCL and RCL 50%(Group H).Specimens were fixed on biomechanical instrum-ents.In each test state,2 N·m posterior rotational and valgus torque was given at the elbow flexion 30°,60°,90°,and 120°,and the lateral rotation angle and valgus angle was measured by the 3D motion capture system,organizing data for statistical analysis.ResultsWith the gradual destruction of the ligament,only transecting upper middle RCL and combined transecting upper middle LUCL and RCL 50% resulted in a gradual increase in the angle of the posterior lateral rotation(p<0.05);only transecting lower middle RCL 50%,only transecting lower or upper middle LUCL 50% and combined transecting lower middle LUCL and RCL 50% will not cause a change in the lateral rotation angle(p>0.05);transecting lower middle AMCL 50% will cause the valgus instability and transecting lower middle AMCL 50% does not cause valgus instability.ConclusionThe upper half of the RCL in the lateral collateral ligament plays an important role in the rotational stability of the elbow joint,while the lower half of the RCL has no significant effect on the rotational stability of the elbow joint.The upper or lower half of the LUCL has no significant effect on the stability of the elbow.The effect of the lower half of the AMCL on the valgus stability is important,while the upper half of the AMCL has no significant effect on the valgus stability of the elbow.