Intraobserver and interobserver reliability of radial torsion angle measurements by a new and alternative method with computed tomography.
OBJECTIVE
To evaluate the intraobserver and interobserver reliability of radial torsion angle measurement using computed tomography.


METHODS
Twelve pairs of cadaver radii and 116 forearms from 58 healthy volunteers were evaluated using axial computed tomography sections measured at the level of the bicipital tuberosity and the subchondral region of the radius. During digital imaging, the angle was formed by two lines, one diametrically perpendicular to the radial tubercle and the other tangential to the volar rim of the distal joint surface. Measurements were performed twice each by three observers.


RESULTS
In cadaveric bones, the mean radial torsion angle was 1.48º (-6º - 9º) on the right and 1.62º (-6 º - 8º) on the left, with a mean difference between the right and left sides of 1.61º (0º - 8º). In volunteers, the mean radial torsion angle was 3.00° (-17° - 17°) on the right and 2.91° (-16°- 15°) on the left, with a mean difference between the sides of 1.58º (0º - 7º). There was no significant difference between each side. The interobserver correlation coefficient for the cadaver radii measurements was 0.88 (0.72 - 0.96) and 0.81 (0.58 - 0.93) for the right and left radius, respectively, while for the volunteers, the difference was 0.84 (0.77 - 0.90) and 0.83 (0.75 - 0.89), respectively. Intraobserver reliability was high.


CONCLUSIONS
The described method is reproducible and applicable even when the radial tubercle has a rounded contour.
Department of Biomechanics, Medicine and Rehabilitation, Ribeirão Preto School of Medicine, São Paulo University, Ribeirão Preto, São Paulo, Brazil.
Luiz Fernando Pinheiro de
LF
Freitas
Cláudio Henrique
CH
Barbieri
Nilton
N
Mazzer
Salomão Chade Assan
SC
Zatiti
Angela Delete
AD
Bellucci
Marcello Henrique
MH
Nogueira-Barbosa
D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D002102:Cadaver; D016001:Confidence Intervals; D005260:Female; D005542:Forearm / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011859:Radiography; D011884:Radius / Q000000981:diagnostic imaging* / Q000502:physiology*; D015203:Reproducibility of Results; D012737:Sex Factors; D018709:Statistics, Nonparametric; D015898:Tomography Scanners, X-Ray Computed; D014102:Torsion Abnormality / Q000000981:diagnostic imaging
J Bone Joint Surg Am. 1988 Dec;70(10):1538-51
3198679
J Bone Joint Surg Br. 2002 Sep;84(7):1070-4
12358375
Clin Biomech (Bristol, Avon). 1999 Jun;14(5):315-20
10521608
J Hand Surg Am. 2007 Apr;32(4):501-9
17398361
J Bone Joint Surg Am. 1984 Jan;66(1):65-70
6690445
J Bone Joint Surg Am. 1995 Jun;77(6):894-902
7782362
J Bone Joint Surg Am. 1997 Jun;79(6):833-7
9199379
J Shoulder Elbow Surg. 2000 Nov-Dec;9(6):536-40
11155310
J Bone Joint Surg Am. 2006 Jul;88(7):1582-8
16818985
J Bone Joint Surg Am. 1992 Aug;74(7):1068-78
1522093
J Hand Surg Am. 2004 Jan;29(1):110-5
14751113