Effect of Labral Tear, Repair and Reconstruction on Strain Distribution in Hip Joint

Abstract

Labral tear can be caused by degeneration or traumatic hip dislocation. It can be treated by mainly two surgical options: labral repair and labral reconstruction by using tissue reconstruction (iliotibial band), depending on the tear size. Finite element analysis was, thus used to simulate strain distribution in different conditions, namely intact labrum, labral tear, labral repair and labral reconstruction, varied under walking and stair-climbing conditions. By applying labral repair, the labrum thickness was reduced, resulted in increased the average maximum strain on labrum tissue by 21.36% compared to torn labrum, while labral reconstruction reduced the average maximum strain through load sharing of iliotibial band by 28.49% compared to torn labrum and 41.21 % compared to labral repair. The equivalent of total strain of the varied cases did not exceed 25,000 microstrain, not causing bone fracture. The hip model was validated by measuring the normal contact force at the hip joint of a cadaver using hip simulation machine and compared with the simulation result. The simulation result corresponded to the validation test.