Abstract
Introduction
High Tibial Osteotomy has become an increasingly popular management option for patients with painful medial compartment osteoarthritis. The Fujisawa method used to calculate the angle of correction is well-documented but there have been no studies to look at the reliability and accuracy of web-based systems to calculate this angle.
Patients and Methods
Patients undergoing valgus high tibial osteotomy between October 2004 and February 2010 who had full-length lower-limb views on the Picture Archiving and Communications System (PACS). The Fujisawa angle and length of osteotomy were calculated by the surgeon and two Orthopaedic registrars who had been appropriately trained.
Results
Thirty X-rays were reviewed in 28 patients. Mean difference between measurements was 0.43 mm (SD 2.45) There was a statistically significant correlation between all three raters (P < 0.001). The greatest correlation was between the Consultant and the more senior trainee (r=0.86) with the lowest correlation between the Consultant and the more junior trainee (r=0.70). Concordance correlation coefficient between raters varied from 0.81 to 0.63. Bland-Altman plot of agreement between the Consultant and senior trainee was excellent showing only two values lying outside 1.96 SD.
Discussion
Comparison of measurements between raters showed increased accuracy with greater experience of the measurement technique. Despite this we show high correlation between raters with measurement accuracy of all raters found within clinically acceptable limits (< 1mm).
Conclusion
Measurement of tibial osteotomy using the fujisawa method on a web-based X-ray interpretation system is accurate and reliable.
