2025 ISAKOS Biennial Congress ePoster
FEMORAL MALTORSION INFLUENCES BOTH PATELLOFEMORAL AND TIBIOFEMORAL CONTACT PRESSURE. A BIOMECHANICAL EVALUATION
Caterina Chiappe , MD, València, València SPAIN
Rodolfo Morales-Avalos, MD, PhD., Monterrey, NL MEXICO
Joan Carles Monllau, MD, PhD, Prof., Esplugues de Llobregat, Barcelona SPAIN
Vicente Sanchis-Alfonso, MD, PhD, Paterna - Valencia SPAIN
Hospital Arnau de Vilanova, València, Comunidad Valenciana, SPAIN
FDA Status Not Applicable
Summary
Femoral maltorsion may be a risk factor for the development of knee osteoarthritis (KOA). Therefore, derotational osteotomy might delay the development of early KOA by reducing intra-articular pressure forces.
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Abstract
Background
Knee osteoarthritis (KOA) is one of the leading causes of disability in adults. Pathogenesis of KOA in the young patient is predominantly related to an unfavorable biomechanical environment at the joint. The connection between valgus/varus deformity as a risk factor for KOA is well-known. A deformity in the coronal plane will cause excessive stress on the knee joint that will cause damage to the articular cartilage. However, the connection between femoral maltorsion (FM) and KOA is less studied. We hypothesize that there is a correlation between FM and intra-articular pressures with the subsequent abnormal loading of the articular cartilage.
Purpose
To investigate the effect of FM on both patellofemoral and tibiofemoral contact pressures.
Methods
Ten cadaveric knees with a mean age of 40.2 years were studied. They were placed on a testing machine designed to apply muscle and ground-reaction forces. The knees were positioned at 0º, 30º, 60º and 90º of knee flexion applying an axial compression force of 1000N to the knee joint. Loads of 218N and 80N were applied to the quadriceps and hamstrings respectively. Patellofemoral as well as medial and lateral tibiofemoral pressures were measured at 10°, 20° and 30º of internal femoral rotation (IFR) and external femoral rotation (EFR) using pressure-sensitive films.
Results
(A) Patellofemoral joint. The medial aspect of the patella showed an increase of contact pressure with progressive simulated EFR from 10º to 30º compared to the pressure at 0º. The strongest effect was measured at 30º of knee flexion (p=0.005) with 30º of EFR (p=0.004) with a value of 2.140 ± 0.1832 Mpa. With IFR there is an increment of contact pressure in the lateral aspect of the patella compared to EFR with the strongest effect at 30º of knee flexion (p=0.0059) with 30° of IFR (P= 0.0002) with a value of 1.352 ± 0.08166 Mpa. (B) Tibiofemoral joint. The medial tibiofemoral contact pressure showed a significant increment from 10° to 30° of EFR compared to the native state. However, medial tibiofemoral compartment contact pressure was smaller with IFR than with EFR but higher than in the control group. Tibiofemoral pressure was significantly lowest in near extension and increased gradually with knee flexion from 0 to 90º in both IFR and EFR. The highest pressure was shown at 90° of knee flexion (P= 0.0006) and 30° of EFR (P= 0.004) with a value of 1.636 ± 0.01878 Mpa. The lateral tibiofemoral contact pressure increased compared to the control group more with IFR than with EFR, increasing progressively with knee flexion from 0 to 90º. The highest pressure was shown at 90° of flexion (P< 0.0001) and 30° of IFR (P< 0.0001) with a value of 1.432 ± 0.004051 Mpa.
Conclusions
Transverse plane alignment influences both patellofemoral and tibiofemoral contact pressure. There is more tolerance in the knee to IFR (anteversion) than to EFR (retroversion).
CLINICAL RELEVANCE
FM may be a risk factor for the development of KOA. Therefore, derotational osteotomy might delay the development of early KOA by reducing intra-articular pressure forces.