Regression of femoral anteversion: A prospective study of intoeing children

Abstract

To study the spontaneous regression of femoral anteversion, 30 children referred to the outpatient clinic for intoeing were followed until at least 15 years of age. The mean observation time was 9 (7-12) years, and all the children were examined three times during the growth period. The mean radiographic angle at the first examination was 42 degrees, at the second examination 36 degrees, and at the last examination 28 degrees. The mean decrease of the AV angle per year was 1.5 degrees, with a considerable range (0.2-3.1 degrees). The mean internal rotation of the hip decreased from 74 degrees to 53 degrees during the observation period, and the external rotation increased from 19 degrees to 37 degrees. While all 30 children had an intoeing gait at the first examination, this disappeared in all but 5 children.

Sex Differences in Clinical Measures of Lower Extremity Alignment

“…13,48,79 Our mean hip anteversion values are within the range of normal values reported in healthy adults (7°-18°), as measured by both clinical and diagnostic methods. 8,36,63,65,71,72 Our findings of greater hip anteversion in females as compared to males agree with those of other studies 8,63 ; but the magnitude of the sex difference is much larger in the current study (approximately 9° versus 2°-4°).…”

Differences in Lower Extremity Anatomical and Postural Characteristics in Males and Females Between Maturation Groups

“…Prepubescent males and females younger than the age of 12 do not differ substantially in height, body mass, girth, muscle strength, bone width, or skinfold thickness. 84 Lower extremity anatomical and postural characteristics also appear to be similar, with studies reporting no difference in femur and tibia lengths, 73 knee laxity, 6,22 hip anteversion, 78,82 or tibiofemoral angle 13,28,64 prior to this age. With the onset of puberty, however, female and male endocrinology diverges, with females secreting more estrogen and males secreting more testosterone.…”

“…Previous studies have identified a relatively linear regression in this angle from early to late maturation. 21,78,82 Comparison of our values to previous studies in the adolescent population is somewhat difficult, as different techniques (radiographic, ultrasound, hip range of motion) were used to measure hip anteversion, and age was used to categorize subjects rather than maturational status. Our data for MatGrp 2 (mean SD, 14.1° 5.9°; range, 6°-30°) are in line with those reported for 13 to 16 year olds in 2 of these studies (means ranging from 8° to 20°), 21,82 and our values in MatGrp 3 (10.9° 5.0°; range, -2.2°-21°) appear to be consistent with those obtained in healthy adult males and females (means ranging from 7° to 18°) using both clinical and imaging measurement methods.…”

“…10,38,54,60,61,66,68 However, our values for MatGrp 1 are substantially lower than those reported elsewhere. 21,78,82 Although using 2 testers introduces the potential for systematic differences between testers, 71 each tester measured subjects in all maturation groups; so it is unlikely that systematic measurement error alone explains these disparate findings. Other factors that may account for this discrepancy are differences in measurement methods, 27 the wide range of ages represented in MatGrp 1 (9)(10)(11)(12)(13)(14), which may confound age-based comparisons, and population differences (athletic versus general school aged clinical measure used in this study is widely accepted 47 and was demonstrated to be valid and reliable, low correlations with radiographic and computed tomography measures 63 may in part explain the lack of agreement between our results and previous findings.…”

“…5,54,74 While the reasons contributing to these sex differences in adults are unknown, there is evidence that anatomy and posture change considerably during growth and development, and may begin to differentiate in boys and girls during maturation. 13,17,40,48,64,78,83 Prior to the onset of puberty, there are few anatomical differences between males and females. Prepubescent males and females younger than the age of 12 do not differ substantially in height, body mass, girth, muscle strength, bone width, or skinfold thickness.…”