33 Mustansiriya Medical Journal Volume 11 Issue 1 June 2012 INTRODUCTION The femoral neck anteversion (FNA) is the inclination of the axis of the femoral neck with reference to the knee axis projected on a plane perpendicular to the shaft axis. [1] A line passing through the center of the femoral head & neck (bisecting the cervical cortex) and meeting the shaft axis at right angle represents the axis of the femoral neck. The coronal line passing through the femoral condyles represents the knee axis. The FNA describes the normal torsion or twist present in the femur measured as the angle between these two axes. [2] The femoral torsion is thought to result from medial rotation of the lower limb bud in early intrauterine life. [3] and becomes identifiable at 7 weeks of gestation. [4] On the average, FNA ranges from 30 o - 40 o at birth and decreases progressively throughout growth. [5] Svenningsen et al. stated that this decreases occurs at a mean rate of 1.5 o per year until about 15 years of age. [6] In adults, clinicians accept an FNA angle range of 10 o -30 o[7] but individual variations are documented and may be related to racial differences, [8] sex (being a little less in men), [9] bone Femoral neck anteversion & hip rotation range in healthy Iraqi children: A clinical anatomical study Sameh S. Akkila, M.Sc. 1 , Ali. A. Ali., F.I.B.M.S. 2 , Ghassan A. Abdulhussein,M.Sc. 1 1 Department of Anatomy Histology & Embryology, College of Medicine, Al-Mustansiriyah University. 2 Department of Surgery, Orthopedics, College of Medicine, Al-Mustansiriyah University. Abstract Background: Femoral neck anteversion (FNA) is a physiological torsion of the femur that plays an important role in the stability & function of the hip joint and has a great impact on the rotational movements of the hip. Abnormal development of the FNA may be associated with a number of orthopaedic problems affecting the hip joint & gait ranging from in-toing gait to disabling osteoarthritis. The assessment of the angle is therefore important in assessing such problems & determining the best course of action in their management. Aims: this study aims at measuring the FNA angle in healthy Iraqi children & examining its impact on hip rotational movements at different age groups. Patients and methods: 36 healthy Iraqi male children divided into 3 age groups were examined clinically for the range of hip rotation & were then subjected to X-ray estimation of the FNA angle of their hips using Ogata’s Biplanar method. Results & conclusions: all the children had FNA angles & hip rotational movements within the normal range for their age with a significant regression in FNA angle with increasing age that may be related to muscular torsional forces applied to growing epiphyses. The FNA angle was inversely proportional to lateral rotation of the hip but directly proportional to medial rotation. Sides to side differences were noticed in tested subjects and were statistically significant in the (8-9 years) age group. This bilateral disparity may normally result from cerebral lateralization or prolonged postural dynamic factors affecting the joints & soft tissues. Date Submitted: 2.4.2010 Date Accepted: 14.4.2011 Address for Correspondence: Dr. Sameh S. Akkila E-mail: samehakkila@yahoo.com Keywords: Femoral neck anteversion, Hip joint rotation, Biplanar X-ray Research Article