Author(s): Vinod K Panchbhavi, Saul Trevino
The aim of this study was to determine if there are intraobserver and interobserver differences in reliability when measuring hallux valgus angles (HVA), 1-2 intermetatarsal angles (IMA), and distal metatarsal articular angles (DMAA) manually compared to computer-assisted means. Our hypothesis was that the measurements taken by computer-assisted methods of these three forefoot angles would be superior in consistency and accuracy compared to manual measurements.
Four examiners studied 20 weightbearing anteroposterior radiographs of patients with hallux valgus. Manual measurements were taken on photographic prints using a goniometer and a fine point pen. Computer-assisted measurements were taken on digitized images using computer software. Three sets of measurements by both of these methods were taken 1 week apart.
There was no statistically significant difference between digital and manual measurements for any of the three angles measured (p .05). However, the reliability of measurements within a range of 5 degrees for both methods was 70.6% for HVA, 84% for 1-2 IMA, and 59% for DMAA.
There were no significant differences in interobserver and intraobserver reliability in measuring 1-2 IMA and HVA, regardless of the method of measurement; however, there was a significant difference in interobserver reliability when measuring the DMAA either on computer or manually (p = <.05).