Correlation of Intraoperative Anthropometric Measurement of Resected Thai Distal Femurs between Unisex and Gender-Specific Implants
Wiboon Wanitcharoenporn MD*, Keerati Chareancholvanich MD**, Chaturong Pornrattanamaneewong MD**
Affiliation : * Department of Orthopaedic Surgery, Buddhachinaraj Hospital, Phitsanulok, Thailand ** Department of Orthopedic Surgery, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand
Objective : To measure the intraoperative anthropometric dimensions of Thai distal femurs in order to correlate that data
with unisex and gender-specific TKR implants, and to analyze the suitability of gender-specific prostheses for Thai female
knees.
Material and Method: Two hundred Thai patients (170 females and 30 males) who underwent unilateral TKR were recruited.
Three parameters of resected distal femurs were measured intraoperatively including anteroposterior dimensions of medial
(APM) and lateral (APL) condyles, and mediolateral (ML) width of total condyles which were compared with the dimensional
data of two femoral implant components, Nexgen LPS-Flex and Gender Solution Nexgen LPS-Flex. Scatter diagrams were
used to assess compatibility; the final type and size of implanted prostheses were recorded.
Results : Thai females had significantly smaller knees than Thai males. The femoral components of both types of prostheses
were found to have a tendency toward ML under-coverage in both female and male femurs. These mismatches were more
noticeable when small-sized, gender-specific prostheses were used. The overall rate of use of gender-specific components
in this study was 15%.
Conclusion : The unisex and gender-specific prostheses evaluated in this study do not appear suitable for Thai knees.
Particular modifications of implants are required for Thai knees.
Keywords : Anthropometric measurement, Total knee arthroplasty, Resected femur, Knee joint prostheses, Knee dimensions
