Clinical Measurement of the Tibio-femoral Angle in Malay Children

BACKGROUND: This study was conducted to find out the age when tibiofemoral angle starts to be in valgus and reaches maximum angle. The differences of the angles between genders were also studied.

METHODOLOGY: This cross sectional study on tibiofemoral angle was conducted among 160 normal healthy children using clinical measurement method. The children between 2 18 months to 6 years old were assigned to 5 specific age groups of 32 children with equal sex distribution.

RESULT: This study had shown a good inter-observer reliability of tibiofemoral angle measurement with intraclass correlation coefficient (ICC) of 0.87 with narrow margin of 95% confident interval (95% CI: 0.73, 0.94). The mean tibiofemoral angle for children at 2 , 3 , 4 , 5 and 6 years old were 2.25° (SD=0.53), 8.73° (SD=0.95), 7.53° (SD=1.40), 7.27° (SD=1.14) and 6.72° (SD=0.98) respectively. The age when they achieved maximum valgus tibiofemoral angle was 3 years old. The maximum mean (SD) tibiofemoral angle for boys, girls and all children were 8.91° (SD=1.17), 8.56° (SD=0.62) and 8.73° (SD=0.95)respectively. The mean tibiofemoral angle showed no statistically significant difference between girls and boys except for the 5-year-old group, in which the mean TF angle for girls was 7.560 (SD=0.95) and for the boys was 6.970 (SD=1.26) with p-value of 0.037.

CONCLUSION: Measurement of tibiofemoral angle using the clinical method had a very good inter-observer reliability. The tibiofemoral angle in Malay population was valgus since the age of 2 years with maximum angle of 8.730 (SD=0.95) achieved at the age of 3 years.