Evaluation of knee joint muscle forces and tissue stresses‐strains during gait in severe OA versus normal subjects

Abstract

Osteoarthritis (OA) is the leading cause of pain and disability in the elderly with the knee being the most affected weight bearing joint. We used a musculoskeletal biomechanical model of the lower extremity including a detailed validated knee joint finite element model to compute lower extremity muscle forces and knee joint stresses-strains during the stance phase of gait. The model was driven by gait data on OA patients, and results were compared with those of the same model driven by data on normal controls. Additional analyses were performed with altered cartilage-menisci properties to evaluate the effects of deterioration during OA. In OA patients compared to normal subjects, muscle forces dropped at nearly all stance periods except mid-stance. Force in the anterior cruciate ligament remained overall the same. Total contact forces-stresses deceased by about 25%. Alterations in properties due to OA had negligible effects on muscle forces, but increased contact areas and cartilage strains and reduced contact pressures. Reductions in contact stresses and increases in tissue strains and transfer of load via menisci are partly due to the altered kinetics-kinematics of gait and partly due to deterioration in cartilage-menisci properties in OA patients. ß

Computational evaluation of altered biomechanics related to articular cartilage lesions observed in vivo

“…The literature‐based loading resulted in contact pressures that agreed well with previously reported contact pressures. For example, during the first peak load of the stance phase, the peak contact pressures on the studied articulating surfaces varied between 7 and 11 MPa which is within the range of 2–15 MPa reported in a number of experimental and numerical studies . Furthermore, for almost all of the models with intact cartilage, the peak compressive strains (Fig.…”

Musculoskeletal loading in the symptomatic and asymptomatic knees of middle‐aged osteoarthritis patients

“…Notably, modeling studies which took into account OA-type co-activity 9,15 reported differences in first peak MCF between patients and controls which were not markedly greater than those found in our present study. Furthermore, Adouni et al 38 found that lowerlimb alignment, which was accounted for in our present study, was more important in determining compartment loads than pure frontal-plane moments applied to the knee.…”

High muscle co‐contraction does not result in high joint forces during gait in anterior cruciate ligament deficient knees

“…Further work is also required to assess potential associations between fear, muscle strength, and joint loading in individuals with ACL deficiency. Also, alteration of the stress environment within the joint requires further analysis, potentially using finite element modeling techniques . While changes in friction and shear stress at the cartilage articular surface are implicated in onset of OA after an ACL injury, whether these changes occur independent of changes in compressive loading still remains to be verified in vivo.…”