Anthropometric measurements for the design of the knee joint prosthesis

Aim: The aim of this study is to obtain anthropometric measurements in both dry bones and living subjects for the ideal design of prosthesis related to knee joint.Material and Method: Anthropometric measurements were performed on 109 femurs and 119 tibias which were present in Anatomy laboratories of Çukurova University, Faculty of Medicine. Anthropometric measurements were also performed on 58 volunteers aged between 55-65 Digital caliper and plastic goniometer were used for dry bone measurements. For living subjects; anthropometric set, goniometer, digital caliper, tape measure, and mechanical size weighing scale were used. Results were analyzed using the SPSS. 17.0 Statistical Package.Program.Results: In measurements relating to femur; medio-lateral width was found similar to eastern population but smaller than those of western population. Antero-posterior length was found smaller than those of eastern and western population. The sulcus intercondylaris width was similar to eastern population but bigger than that of western population. There was a slight difference in the collodiaphyser angle when the left side was compared with right side. Except intercondylar notch width, a strong correlation among other measurements was determined (p<0.001). In the measurements concerning the tibia; Antero-posterior length and medio-lateral width were smaller than those of western population, but closer to eastern population. Most of the measurements on the right side were bigger than those of left side. Right and left Q angles in females were smaller when compared with those of male. There were positive correlation between height and range of motion of knee (p<0.001), negative correlation between weight and body mass index (p<0.001) and ROM of knee, and a weak correlation between height and Q angle (p<0.001). The biiliac diamater, thigh and leg circumference were bigger in females than in males, but ROM of knee and Q angle were lower than in males. Moreover, tibia was shorter in females when compared with males.Conclusion: The success of total knee arthroplasty is dependent on the accurate measurements, cuts during the operation and the choice of appropriate sized component. In order to minimize the disharmony between the surface of resected bone and knee prosthesis, the morfometric studies both in dry bones which are constituent of the knee joint, and in living subjects with a high osteoarthrit prevelance (aged between 55-65) should be taken into consideration. These measurements may help to orthopaedic surgeon and provide data for designing of appropriate sized and shaped knee prosthesis.Key Words: Anthropometric measurements, knee morphology, femoral component design, tibial component design, total knee arthroplasty