P236 - Bone morphotype and early osteoarthritis

Corresponding Author
Peter Verdonk, Active Implants, Smith and Nephew, Depuy Synthes, consultant
Presentation Topic
Poster Rating



Degenerative osteoarthritis has been investigated in relation to multiple factors as malalignment, BMI, activity level and genetics. The purpose of this pilot study was to investigate knee shape differences in relation to early medial compartment degeneration. The study hypothesis is shown in Figure 1.

icrs figure 2.png

Methods and Materials

Twenty patients with small medial femoral condyles (SMC), suffering from pain in the medial compartment and 20 control subjects without complaints in the medial compartment were included in the study. MRI scans were converted into 3D knee models, the bone models were uniformly scaled to exclude size differences from the analysis and a landmark based shape analysis was performed.


The medial condyle of the femur and medial plateau of tibia of the study group were significantly smaller in the mediolateral (-8%) as well as in the anteroposterior direction (-6% for the femur and -2% for the tibia), indicating a smaller contact area in the medial compartment , which may consequently lead to higher contact pressures (Figure 2).

Overall, the femur was 1% wider and the tibia was 4% smaller in the SMC group compared to the control group, indicating a mismatch between the femur and tibia width in the SMC group.

The femoral notch width and tibia eminence width were 2% wider in SMC group and the tibial spines were 34% higher and located 5% (lateral spine) and 10% (medial spine) more posteriorly in the SMC group compared to the control group.icrs figure 2.png


These SMC knees show a distinct morphology with smaller areas in the medial compartment and a width mismatch between the femur and tibia. Further analyses on larger populations are required to confirm these observations and to estimate the incidence of SMC in a non-biased population. These preliminary results suggest that SMC knees might be at higher risk for early degeneration in the medial compartment.