Direct measurement of acetabular radiographic version using an ordinary goniometer – a precision study

Abstract

(2011) Direct measurement of acetabular radiographic version using an ordinary goniometer -a precision study, Computer Aided Surgery, 16:4, 196-201, DOI: 10.3109/10929088.2011 Abstract Objective: The acetabular version following total hip arthroplasty is an important prognostic factor. Computer navigation serves as a precise tool during hip arthroplasty, which requires precise measurement to verify the effect of the procedure. Wan and colleagues have reported an innovative method for measuring acetabular radiographic version with an ordinary goniometer. Our objective was to study the precision of this method. Methods: We derived the underlying mathematical principle of Wan's method and produced a correction formula and chart. Forty-eight computer-synthesized radiographs were used to study the method and its mathematical correction. Ten real radiographs were used to detect intra-observer difference. The paired t-test was used for statistical analysis. Results: There was a significant difference between synthetic acetabular radiographic version and the measurement obtained with Wan's method ( p50.05), but there was no difference after mathematical correction ( p ¼ 0.15). For smaller radiographic version (520 o ), there was no statistical difference using Wan's method ( p ¼ 0.054). Conclusions: The method of Wan and colleagues can be used when acetabular radiographic version is less than 20 . For larger radiographic versions, however, mathematical correction is necessary to obtain precise results.

Laser projector method for measuring postoperative acetabular anteversion after total hip replacement

“…To date, the documented techniques for assessing anteversion could be classified into two-dimensional (2D) and three-dimensional (3D) methods. 2D methods included the trigonometric (3-5), the protractor (2,(6)(7)(8)(9)(10), and the computerized ellipse (11) method. The computerized tomography (12) (CT) method is representative of 3D method, which pertains an excellent solution but is clinically unpractical due to its high cost and risk of radiation exposure.…”

Computerized ellipse method for measuring acetabular version after total hip replacement – a precision study using synthetic and real radiographs

“…Many methods for measuring version have been published to date. These can be categorized into three groups: the trigonometric method [2][3][4], the protractor method [1,[5][6][7][8][9], and the computer tomography method [10]. The first two groups are two-dimensional (2D) methods, while the last is a three-dimensional (3D) method.…”