Abstract
Aim
To assess the influence of posterior slope on Knee flexion and function in Asian and Caucasian populations.
Material & methods
We have conducted a prospective comparative study of 109 Asian and Caucasian posterior tibial slopes. All data has been collected prospectively and includes personal data (height, weight, tibial measurements), ASA grading, knees scores and range of movement. Analysis was performed for the whole group and comparisons were made between the two sets of patients. Minimum follow-up was two years.
Results and conclusion
Patients were well-matched for Age, Sex and ASA grading at time of surgery. The system for TKR we used aims for a slope of 5 degrees.
The average posterior slope in Caucasian patients was 3.9 degrees pre-TKR and 4.55 degrees post-TKR. However in Asian patients the average slope was 10 degrees pre-TKR and 4.45 degrees post-TKR. We have analysed the significance of this change in Asian patients and compared this with data for range of movement and Knee score at a minimum of two years. The Asians tend to have greater pre-operative posterior slopes as compared to Caucasians. The changes in knee flexion, knee scores and knee functions (Knee Society Clinical Rating Systems Scores) in the two groups were not statistically significant.
Although previous studies have shown that decreasing the posterior slope would reduce the range of flexion after TKR, our study has shown that posterior slope has no role in changes in knee flexion, knee scores and knee functions. We therefore feel that increased posterior tibial slope in Asian patients should not deter one from changing their practice of using normal tibial cuts as final post-operative results have no bearing on it.
