Dear biomch-l subscribers

a while ago I posted a question about the measurement of femoral
anteversion from CT and conventional X-ray scans. Thanks to all who
replied. Below you will find my original question followed by a summary
of the responses I got.

Thanks again.

Francesco La Palombara

Francesco La Palombara

Istituti Ortopedici Rizzoli Tel: +39.(0)51.636 6520
Lab. di Biomeccanica Fax: +39.(0)51.583789

via di Barbiano 1/10 E-mail:
I-40136 Bologna (please use "To Franz" as subject)


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I am looking for a reliable and accurate manual or
computer-assisted technique for measuring femoral anteversion using data
deriving from CT and/or conventional X-ray scans.

I am particularly interested in methods which have been validated
through comparison with intraoperative or post-mortem direct
measurements. I would also like to know where to retrieve information on
normal and pathological value ranges for this parameter. One more
question: does anybody have the complete reference to the paper(s) in
which Reikerås proposes his approach?

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Dr Georg Bergman and his collaborators at the Biomechanics
Laboratory of the Orthopaedic Hospital of the Free University of Berlin
Oskar-Helene-Heim (Clayallee 229, 14195 Berlin, Germany, Tel: +49 30
81004 273, Fax: +49 30 81004 275, E-mail:,
WWW: have developed a
computer-assisted technique for the evaluation of ultrasound
measurements, featuring a reproducibility of about 3 degrees. They are
now validating the technique through clinical trials.

Dr Patrick Costigan of the School of Physical and Health Education
at Queen's University (Kingston, Ontario, Canada, Tel: ++613 545 6603
E-mail: developed a method for computing femoral
anteversion from two X-ray views as part of his PhD thesis. Here is an
overview of his method:

The method involves taking two x-rays; one is an AP view of the hip
while the other is the AP view rotated by 30 degrees about the long
axis. This method was developed using dry bones as test specimens. The
actual anteversion angle was also measured directly with a 3D digitizer
and with measurements from CT images. The data for dry bones follows:

The anteversion angle measured by three methods.

Bone Direct CT X-ray
A76 0.6 0.5 11.0
AD58 -4.6 0.0 10.3
S100 20.4 22.3 23.7
S104 19.5 24.8 19.4
S105 -8.3 -5.0 7.5
S162 0.1 4.0 15.2
S175 -25.4 -14.5 0.2
S192 10.6 7.3 14.1
S212 2.0 -2.0 6.6
S237 18.8 20.5 26.1
S244 -2.4 18.8 19.0
S250 2.3 1.5 11.7
S262 22.4 26.8 28.4
S269 25.6 22.3 26.9
S316 12.9 16.0 18.4
S338 10.3 20.8 21.4
S341 11.8 18.5 21.1
S342 5.0 8.0 13.6
S346 19.2 23.0 23.7
S8 -10.4 -7.0 4.5
S89 12.3 15.0 15.9
XYZ 0.5 3.8 13.9

Using a regression procedure I developed regression equations to predict
both the direct and CT measurements from the x-ray measurement. The
resulting equations were:

Direct = -17.5 + (1.50 * radiographic) r2=0.82 S.E.E. = 5.51
CT = -14.0 + (1.51 * radiographic) r2=0.92 S.E.E. = 3.55

The Standard Error of The Estimate (SEE) is the standard deviation of
differences between the actual measures (either direct or CT) and the
respective predicted measure (the mean is approximately zero).

Dr Dieter Rosenbaum of the Kinesiology Lab at the Klinik und
Poliklinik fuer Allgemeine Orthopaedie of the Westfaelische
Wilhelms-Universitaet Muenster (Albert-Schweitzer-Str. 33, D-48129
Muenster, Germany, Tel: +49 251 834 7981/7995, Fax: +49 251 834 7989,
E-mail: suggested to contact Martin Simnacher and
Peter Keppler at the University of Ulm, who developed a technique based
on ultrasound measurements. Their E-mail address is

Leonard D'Addesi of the Human Performance Laboratory at Thomas
Jefferson University (130 South 9th Street, Suite 830, Philadelphia, PA
19107-5233, USA, E-mail: is completing
his MS thesis on the assessment of femoral anteversion using motion
analysis. He sent a large list of references which you can find below.


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Christoph Roth of the Orthopaedic Research Institute, Inc. (E-mail: suggested the following references:

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