Purpose: The objective of this study was to analyze the morphology of the medial tibial plateau and lateral tibial plateau in Chinese knees and compared these measurements and features with those of commercial unicondylar tibial baseplates.
Methods: Three-dimensional knee models were reconstructed from computed tomography slices of 81 subjects. Among the series, 27 knees were from male subjects and 54 knees from female subjects. The dimensions and shape of the medial and lateral tibial plateaus were measured and compared with six commercially available unicondylar tibial baseplates.
Results: The results showed significant differences between the shapes of the medial and lateral tibial plateaus. For the lateral tibial plateau, the shape was symmetric about the mediolateral axis. The medial plateaus presented their widest mediolateral width in an obviously more posterior position than the lateral compartment. Additionally, the plateau aspect ratio decreased with increasing mediolateral dimensions, in contrast to the constant aspect ratio shown by conventional unicondylar knee prostheses.
Conclusion: Compartment-specific designs may optimize coverage between the prosthesis and resected tibial surface. The morphometrical measurements presented may allow manufacturers to design tibial baseplates that accommodate the structural variability between different ethnic groups.
Level of evidence: Prospective comparative study, Level II.