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Hello colleagues - At the risk of annoying, if not flat out infuriating, any more of the group of clinicians and researchers who prefer camaraderie to accuracy and relevance, I realize that in the US, the term anteversion (directed forward) is commonly used to describe femoral antetorsion (twisted about the longitudinal axis, such that the longitudinal head and neck bisection is directed anteriorly when the posterior border of the condyles (the transcondylar axis) is aligned on the frontal plane). However, terms anteversion and antetorsion are NOT synonymous. You change the femoral head and neck anteversion angle with every change in femoral rotation position. Hip lateral rotation increases the head and neck anteversion angle relative to both the acetabulum (which is also anteverted) and to the frontal plane, for example, while the torsional geometry of the femur remains unchanged. Whoever it was that identified a twisted femur - that leaves the head and neck bisection directed anteriorly (anteverted) when the posterior border of the condyles (the transcondylar axis) was lying on the table (the frontal plane) - as femoral anteversion (what if the femoral head were heavy enough to drop to the table instead?) created a LOAD of havoc and confusion. This mess is evidently not a problem for European clinicians who do not use the term anteversion to describe antetorsion unless they come to the US to present a paper on the subject. My best source on this issue is Dietrich Tonnis et al (1987) Congenital Dysplasia and Dislocation of the Hip In Children And Adults. New York: Springer-Verlag. In the second chapter, he states that in the western hemisphere, anteversion is used inaccurately lieu of antetorsion. In order to facilitate your mental processing, I suggest you get some aluminum foil, get 2 marker pens and a drum stick or something that could be used for the femoral shaft. Use the foil to wrap the marker pens onto each end of the stick at 90-degrees to it, add a small foil bulb for the femoral head to one end, and regard the other end as the condyles and knee axis. What's the point of niggling over nomenclature in this case? The magnitude of femoral antetorsion normally diminishes from birth - when the mean approaches 40 degrees - through adulthood - when the mean rests between 15 and 20 degrees.(Shands AR, Steele MK. (1958) Torsion of the femur: a follow-up report on the use of the Dunlap method for its determination. J Bone Joint Surg. 40-A(4):803-816.; Tonnis D, Heinecke A. (1991) Diminished femoral antetorsion syndrome: a cause of pain and osteoarthritis. J Pediatr Orthop. 11(4):419-431) At age 3 or 4 years, nondisabled children who have a normal femoral antetorsion of about 30 degrees walk with their knee axes aligned on or very near the frontal plane, and the patellae in midline at the midstance and midswing phases of gait. They therefore use about 30 degrees of femoral head and neck anteversion relative to the frontal plane at those same moments of the gait cycle. Adults with 16 degrees of femoral antetorsion use 16 degrees of anteversion by comparison. Researchers who implement 3-D skeletal modeling techniques to visualize normal and pathologic musculoskeletal alignment in gait might not bring this distinction to their computerized visualizations. If a child with increased femoral antetorsion (common to many with cerebral palsy, for example), shows medially-rotated knee axes in gait, the unwitting clinician who wishes to improve the appearance of the gait pattern by applying lateral rotation straps or cables might place the femoral head and neck in excessive anteversion, and risk the load-bearing status of the hip joint. However, since children normally use more functional femoral head and neck anteversion than adults, the femur could be safely so positioned as long as the head and neck align within 10 degrees of the reported normal mean for the child's age. (Shands and Steele's norms fall near the middle of the span of reported norms in the collective graph that appears in Tonnis et al (1991). So they are like a median for the reported means, and I use them as a clinical guide. Furthermore, the authors state that 80% of their findings fell within 10 degrees of the means.) Furthermore, if the rotation angle of the knee axis is known via computerized kinematic analysis, and the femoral torsion status is known, then the functional angle of the femoral head and neck could be calculated and compared with the norms reported by Shands and Steele. Perhaps most children with pathologic gait related to increased femoral antetorsion use a relatively normal femoral head and neck anteversion angle which would preserve the load-bearing function of the more proximal joint, and display the consequences of the torsional deviation at the (secondary) knee joint. I would appreciate hearing from anyone out there who either shares this concern over our deteriorating nomenclature, finds this particular information in any way useful, or would like to offer a different point of view. Thanks for your time. Beverly Cusick, PT, MS PS: I've also addressed this aspect of LE skeletal development in my courses on developmental biomechanics, on my website, and in the opening monograph for the home study on Physical Therapy in Pediatrics, published in 2000 by the APTA's Orthopedic Section. (Info also available on my website: www.gaitways.com . The home study package is still available, but I do not think they are conducting a course on it anymore.) ========================================= Beverly Cusick, MS, PT [log in to unmask] http://www.gaitways.com