American Journal of Clinical Medicine Research
ISSN (Print): 2328-4005 ISSN (Online): 2328-403X Website: Editor-in-chief: Dario Galante
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American Journal of Clinical Medicine Research. 2014, 2(3), 57-60
DOI: 10.12691/ajcmr-2-3-2
Open AccessArticle

Are Measurements of Sacral Slopes Reliable?

Norio Imai1, , Dai Miyasaka1, Yoji Horigome1, Hayato Suzuki1, Ryota Takubo1 and Naoto Endo1

1Department of Orthopaedic Surgery, Niigata University Medical and Dental Hospital, Niigata, Japan

Pub. Date: June 15, 2014

Cite this paper:
Norio Imai, Dai Miyasaka, Yoji Horigome, Hayato Suzuki, Ryota Takubo and Naoto Endo. Are Measurements of Sacral Slopes Reliable?. American Journal of Clinical Medicine Research. 2014; 2(3):57-60. doi: 10.12691/ajcmr-2-3-2


Background: Malpositioning during total hip arthroplasty may cause dislocation, pain, and other complications. To evaluate the potential of sacral slope (SS) as a reliable parameter of pelvic flexion. Methods: We developed a model of pelvic flexion to determine the intraobserver and interobserver variability and reliability of SS measurements by lateral radiography by three independent observers. Results: Measurement error was 1.2 and the intraobserver reliability was moderate to substantial (Interclass correlation coefficient: 0.31 to 0.66). Based on the Spearman-Brown formula, the measurement is reliable if it is done at least seven times by two observers, and four times by three observers. Conclusions: The data suggest that measurement of SS of pelvic flexion is a clinically useful parameter for the optimization of THA conditions.

anterior pelvic plane lateral radiograph total hip arthroplasty sacral slope pelvic flexion angle accuracy

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