Comparison of four methods for measuring femoral anteversion

Abstract

This study evaluates the most valid and reproducible method for directly measuring anteversion (torsion) in dried femora using a commercially available measuring machine. Each femur was placed horizontally on the surface of the machine and readings were obtained from the head, the shaft distal to the lesser trochanter, and the distal end. Using computer software, four different anteversion angles were calculated: the center head-neck line to the retrocondylar line (Method 1); the center head-neck line to the transcondylar line (Method 2); the anterior head-trochanter line to the retrocondylar line (Method 3); and the anterior head-trochanter line to the transcondylar line (Method 4). The methods were applied to 20 femora, which were measured twice by one observer. The most reproducible method of measuring femoral anteversion uses the bone surfaces on the anterior aspect of the head and greater trochanter and on the posterior aspect of the condyles (Method 3,95% confidence limits of t 0.4"). The other methods are shown to be reproducible to t 2.4", t 3.3" and t 1.7" (Methods 1,2, and 4, respectively, 95% confidence limits). Conversion factors between the different methods are: 12.5" + 0.8 x (anteversion angle) to change each of Method 2 to Method 1 and Method 4 to Method 3; and 8" + 0.7 x (anteversion angle) to change each of Method 1 to Method 3 and Method 2 to Method 4 (correct to within t 3"). o 1993 Wiley-Liss, Inc.

Femoral Anteversion : Comparison By Two Methods

“…Moreover any potential inaccuracies in identifying central points is avoided. This finding is consistent with Kirby et al, 1993 [2] (95% CL +/-0.4°). Likewise the reliability of method -1 in the present study (95% CL +/-3.20) is comparable with that of Kirby et al, 1993 (95% CL +/-2.14).…”

“…The increased angle of anteversion is associated with failure of treatment of CDH, Perthes disease, slipped epiphysis of femoral head, cerebral palsy, anterior poliomyelitis, medical femoral torsion, postural defects, squinting patellae, apparent genu valgum, external tibial torsion , flat foot, and intoing. [1,2] The decreased femoral torsion has been shown to be associated with toing out, rickets, chondrodystrophy. [ 10 ].…”

The Inter- and Intraindividual Anatomical Relationship of the Femoral Anteversion and Distal Femoral Rotation. A Cadaveric Study on the Femoral Anteversion Angle, Posterior and Inferior Condylar Angle Using Computed Tomography

“…The lowest variability (i.e. Method 3.95% confidence limits of ±0.4˚) is shown when surgeons use the PCL as reference line [25].…”

Difficulty in Fixation of Fracture Neck of Femur in a Paralytic Hip: A Case Report

“…9,10 The decreased femoral torsion has been shown with toeing out, rickets, and chondrodystrophy. Researchers worldwide have used various methods and stated CT-Scan is most reliable method.…”