Torsion deformity and joint loading for medial knee osteoarthritis.
ABSTRACT The consequences of lower limb torsion deformity on knee loading in knee osteoarthritis are poorly understood. The purpose of this study was to quantify the associations between the mechanical axis, tibial torsion and knee loading in subjects with medial knee OA and in controls.
Twenty-four subjects: end-staged medial knee osteoarthritis (OA) with apparent torsion deformity (TKO, n=6) and without torsion deformity (KOA, n=8) and controls (CON, n=10) were imaged using long standing lower extremity (LSLE) radiographs and computed tomography (CT). Medial knee loading was assessed using the internal knee varus moment determined by gait analysis. The LSLE mechanical axis, CT tibial torsion and the foot progression angle were used to predict medial knee loading.
The TKOs had significantly greater mechanical axis varus and knee varus moment compared to KOAs and CONs. The regression model predicting medial knee loading using the mechanical axis (β=0.898), tibial torsion (β=0.264) and foot progression angle (β=-0.369) showed a goodness of fit of 0.774.
Medial knee loading was predicted by the mechanical axis and the foot progression angle. Future longitudinal studies are needed to assess the role of tibial intorsion during disease progression and following total knee replacement surgery.
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ABSTRACT: The axial alignment of the lower extremities of twenty-five normal male volunteers whose mean age was thirty years was studied using a standardized radiograph of the entire lower extremity. The extremities were found to be in a mean of 1.5 degrees (right) and 1.1 degrees (left) of varus angulation at the knee between the tibial and femoral mechanical axes. The transverse axis of the knee lacked a mean of 3.0 degrees (right) and 2.6 degrees (left) of being perpendicular to the mechanical axis of the tibia. The anatomical axis of the femur did not pass through the center of the knee.The Journal of Bone and Joint Surgery 07/1987; 69(5):745-9. · 3.23 Impact Factor
Article: Dynamics of knee malalignment.[show abstract] [hide abstract]
ABSTRACT: The dynamics of malalignment are based on the combination of the static limb alignment and the dynamics of loading at the knee during walking and other activities of daily living. Dynamic loading at the knee can be influenced by subconscious control of limb position such as foot placement, active muscle contraction, passive soft-tissue stability, as well as the speed of walking. The loads that are generated during these dynamic activities are substantially greater than the loads that can be generated during static postures. Therefore, limb alignment based on static radiographic measurements provides one component to the complete analysis of the factors influencing loading at the knee joint. Loading at the knee joint is an important consideration in the progression of degenerative processes at the knee, as well as in the planning and selection of certain treatment modalities. Dynamic malalignment that occurs during activities such as gait should be considered in evaluating the progression of disease processes as well as the selection of appropriate treatment modalities.Orthopedic Clinics of North America 08/1994; 25(3):395-403. · 1.25 Impact Factor
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ABSTRACT: This article's goal is to review the causes of limb rotation and arthritis and establish the correlation between the two entities. Evidence cited in this article demonstrates that malrotation is coupled with axial malalignment and both are associated with arthrosis of the hip, knee, and ankle. The clinical significance of this observation is that the prognosis of arthrosis developing in a malrotated limb may be predicted. Furthermore, the durability of an osteotomy, arthroplasty, or other surgical intervention may be limited if the intrinsic rotational deformity is not addressed.Orthopedic Clinics of North America 08/1994; 25(3):405-14. · 1.25 Impact Factor