### Abstract

We invented a standardization method to measure the cup's anteversion after total hip arthroplasty without the influence of patient's position. We measured 68 radiographs of 10 patients after total hip replacement (THR) and calculated the error of each measurement, defined as the difference with the average of the same measuring method on the same patient. We also calculated the repeatability standard deviation (RSD) of each method according to the American Society for Testing and Materials, ASTM E691. Mean absolute inter-examination angle error, defined as the average of the absolute deviations, was 0.75° for standardized anteversion (range 0.03-2.51°), as compared with those without standardization, 2.30° (range 0.04-13.04°). The inter-examination measurement reliability (precision), defined as one RSD, was 0.99° for standardized anteversion, as compared with those without standarization, 3.50°. There is no difference between patients four and five without (p = 0.097). There is a significant difference with standardization (p < 0.0001). Our study demonstrated that this mathematical method is a precise tool to measure the anteversion of the acetabular cup. We hope that it can be used widely in the future.

Original language | English |
---|---|

Pages (from-to) | 105-119 |

Number of pages | 15 |

Journal | Computational and Mathematical Methods in Medicine |

Volume | 9 |

Issue number | 2 |

DOIs | |

Publication status | Published - Jun 1 2008 |

Externally published | Yes |

### Fingerprint

### Keywords

- Acetabulum
- Anteversion
- Radiographs
- Standardized

### ASJC Scopus subject areas

- Modelling and Simulation
- Biochemistry, Genetics and Molecular Biology(all)
- Immunology and Microbiology(all)
- Applied Mathematics

### Cite this

*Computational and Mathematical Methods in Medicine*,

*9*(2), 105-119. https://doi.org/10.1080/17486700701865265

**A simple mathematical standardized measurement of acetabulum anteversion after total hip arthroplasty.** / Liaw, Chen Kun; Yang, Rong Sen; Hou, Sheng Mou; Wu, Tai Yin; Fuh, Chiou Shann.

Research output: Contribution to journal › Article

*Computational and Mathematical Methods in Medicine*, vol. 9, no. 2, pp. 105-119. https://doi.org/10.1080/17486700701865265

}

TY - JOUR

T1 - A simple mathematical standardized measurement of acetabulum anteversion after total hip arthroplasty

AU - Liaw, Chen Kun

AU - Yang, Rong Sen

AU - Hou, Sheng Mou

AU - Wu, Tai Yin

AU - Fuh, Chiou Shann

PY - 2008/6/1

Y1 - 2008/6/1

N2 - We invented a standardization method to measure the cup's anteversion after total hip arthroplasty without the influence of patient's position. We measured 68 radiographs of 10 patients after total hip replacement (THR) and calculated the error of each measurement, defined as the difference with the average of the same measuring method on the same patient. We also calculated the repeatability standard deviation (RSD) of each method according to the American Society for Testing and Materials, ASTM E691. Mean absolute inter-examination angle error, defined as the average of the absolute deviations, was 0.75° for standardized anteversion (range 0.03-2.51°), as compared with those without standardization, 2.30° (range 0.04-13.04°). The inter-examination measurement reliability (precision), defined as one RSD, was 0.99° for standardized anteversion, as compared with those without standarization, 3.50°. There is no difference between patients four and five without (p = 0.097). There is a significant difference with standardization (p < 0.0001). Our study demonstrated that this mathematical method is a precise tool to measure the anteversion of the acetabular cup. We hope that it can be used widely in the future.

AB - We invented a standardization method to measure the cup's anteversion after total hip arthroplasty without the influence of patient's position. We measured 68 radiographs of 10 patients after total hip replacement (THR) and calculated the error of each measurement, defined as the difference with the average of the same measuring method on the same patient. We also calculated the repeatability standard deviation (RSD) of each method according to the American Society for Testing and Materials, ASTM E691. Mean absolute inter-examination angle error, defined as the average of the absolute deviations, was 0.75° for standardized anteversion (range 0.03-2.51°), as compared with those without standardization, 2.30° (range 0.04-13.04°). The inter-examination measurement reliability (precision), defined as one RSD, was 0.99° for standardized anteversion, as compared with those without standarization, 3.50°. There is no difference between patients four and five without (p = 0.097). There is a significant difference with standardization (p < 0.0001). Our study demonstrated that this mathematical method is a precise tool to measure the anteversion of the acetabular cup. We hope that it can be used widely in the future.

KW - Acetabulum

KW - Anteversion

KW - Radiographs

KW - Standardized

UR - http://www.scopus.com/inward/record.url?scp=42349102397&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=42349102397&partnerID=8YFLogxK

U2 - 10.1080/17486700701865265

DO - 10.1080/17486700701865265

M3 - Article

VL - 9

SP - 105

EP - 119

JO - Computational and Mathematical Methods in Medicine

JF - Computational and Mathematical Methods in Medicine

SN - 1748-670X

IS - 2

ER -