15th EFORT Congress 2014 !� London � 4-6 June 2014!

Digital Templating And Preoperative Data Analysis Of Total Hip Arthroplasty! The Double Marker Calibration Method!

P. Andrés-Cano, E. Cruz, J.R. Cano, E. Guerado!Department of Orthopedic Surgery ∙ Hospital Costa del Sol ∙ University of Málaga ∙ Marbella ∙ Málaga ∙ Spain!

#2110!

Material & Methods!Consecutive prospective cohort of patients waiting for uncemented THA.!

Introduction & Objetives!Preoperative templating is a challenging step in total hip arthroplasty (THA)1. The ability to determine magnification of the radiograph is critical to get an accurate and reliable planification2. !

Results!

References!1.  Unnanuntana A et al. The accuracy of preoperative templating in cementless total hip arthroplasty. J Arthroplasty. 2009;24:180-186.!2.  Bayne CO et al. Evaluation of the accuracy and use of x-ray markers in digital templating for total hip arthroplasty. J Arthroplasty. 2009;24:407-413.!3.  King RJ et al. A novel method of accurately calculating the radiological magnification of the hip. J Bone Joint Surg Br. 2009;91:1217-1222.!4.  Baxter JA et al. The accuracy of automatic calibration of digital pelvic radiographs using two different scale markers: a comparative study. Hip Int. 2012;22:82-89.!5.  Berstock JR et al. A comparison of digital and manual templating using PACS images. Ann R Coll Surg Engl. 2010;92:73-74.!6.  Kumar PG et al. Reproducibility and accuracy of templating uncemented THA with digital radiographic and digital TraumaCad templating software. Orthopedics. 2009;32:815.!7.  White SP et al. Assessment of magnification of digital pelvic radiographs in total hip arthroplasty using templating software. Ann R Coll Surg Engl. 2008;90:592-596.!8.  Whiddon DR et al. Digital templating in total hip arthroplasty. Instr Course Lect. 2008;57:273-279.!

Conclusion!

Independent variables !

Dependent variables!

Statistical analysis!- Demographic and preoperative data !- Expected sizes!

Group A!PACS marker5!

Group B !Double Marker3,4!VS!

Both calibration methods in the same patient!

Utility and precision of preoperative templating of THA comparing!

A new Double Marker calibration method of pelvic radiograph has recently been proposed3,4. Its clinical effectiveness has not been proven yet.!

- Bivariate analysis!- Correlation (ICC)!!!!- Magnification 7!

- Accuracy!!!

Disclosures: Authors declare no conflict of interest. No benefits in any form have been received from a commercial party related directly or indirectly to the subject of this article.! !

•  THA templating using digital radiographs calibrated with a double marker method is more reliable than using PACS!

Figure 2: THA Templating!a.  Preop (ball: anterior marker, rods: posterior)!b.  Template!c.  Postop!

Figure 1: Double Marker Calibration Method!

- n= 25!- Digital radiographs!- Software: Traumacad© 6!- Templating !- THA (Accolade II Stem and Trident Tritanium cup) !!

c.!

b.!

a.!