Development of the tibiofemoral angle in a cohort of Nigerian children during the first 3 years of life

Abstract

Purpose Findings from cross-sectional studies of knee angle development in Nigerian children vary in values and in the age at which the varus angle changes to the valgus angle. This study was conducted to describe knee angle development and to determine the age when the knee angle changes from the varus to the valgus angle. Methods This was a longitudinal survey of 152 Nigerian children recruited within 3 weeks of life and followed up monthly until age 3 years. Their knee angle was measured using clinical methods. Results The mean tibio-femoral/varus knee angle (13.2 ± 3.8°) at birth-3 weeks of life decreased sharply to 5.6 ± 0.7°at 9 months, increased slightly to 6.3 ± 1.1°at 13 months, and then decreased again up to age 18 months (0.3 ± 2.1°). The mean valgus knee angle increased from -2.4 ± 2.5°at 19 months of life to -8.5 ± 2.5°a t 27 months and then decreased to -7.7 ± 2.2°at 36 months. Intercondylar/intermalleolar distances (ICD/ IMD) showed a similar pattern, changing from an extreme varus knee (ICD) at birth-3 weeks of life (2.5 ± 0.7 cm), decreasing to 0.6 ± 0.2 cm at 9 months, increasing to 0.8 ± 0.5 cm at 12 months, and decreasing to 0.1 ± 0.4 cm at 15 months. The mean IMD increased from -0.1 ± 0.8 cm at 16 months of life to -2.0 ± 1.5 cm at 29 months and then decreased up to 36 months. Our tri-modal analysis showed that the transition from the varus to the valgus angle was between 18 and 19 months. Conclusion Our findings suggest that the developmental pattern of the knee angle in Nigerian children is at maximal varus at birth, neutral at 18 months of life, and valgus at 19 months, with the valgus angle continuing to increase up to 36 months.

Developmental pattern of tibiofemoral angle in healthy north-east Indian children

“…Weight was recorded using a simple weighing scale which could measure a minimum difference of 0.1 kg. BMI was calculated using the formula weight/height 2 where weight is in kilograms and height is in metres. Limb length was measured as distance from the ASIS to the medial malleolus on both sides using a measuring tape.…”

“… 1 The angle may also be expressed indirectly as intercondylar distance (ICD) and intermalleolar distance (IMD). 2 This alignment is subjected to the effects of genetic factors, intrauterine posturing, nutritional status, hormones, ligamentous laxity, anatomical peculiarities of femur and tibia which change with age, adaptive changes to weight-bearing and differential growth of the physis. 3 - 10…”

“…These angular deformities may be physiological or pathological 14 , 15 as during normal development the knee undergoes sequential physiological changes which leads to change in lower limb axial alignment from varus to valgus. 1 , 2 , 11 , 16 , 17 However, such angular deformities may also develop on account of pathology at the epiphysis, the physis or the metaphysis This may in turn lead to abnormal loading of the joint and, if uncorrected, may predispose to painful knee, degenerative arthritis and joint instability. 15 , 18…”

“…The results from previous studies suggest that differences in the physiological range of TFA may arise with race and ethnicity, apart from age, gender, height, weight and body mass index (BMI). 1 , 2 , 11 , 13 , 17 , 19 - 24 Hence, sound knowledge of the developmental pattern of knee angle in children of the specific population is necessary.…”

Study of knee angle in tribal children of Andhra Pradesh

“…Most of the parents unaware of this physiological variation worry about their children. Knee angle in terms of TFA (°) is generally determined by photographic, 2,3 radiological 1,4 and clinical [5][6][7][8][9][10][11][12][13] techniques. Clinical techniques are adopted in this study because of their reliability, easy applicability, and reproducibility.…”