Related Experiment Video
Updated: Oct 5, 2025

3D Ultrasound Imaging: Fast and Cost-effective Morphometry of Musculoskeletal Tissue
Published on: November 27, 2017
Semi-automatic software-based 3D-angular measurement for Weight-Bearing CT (WBCT) in the foot provides different
Martinus Richter1, Fabian Duerr1, Regina Schilke1
1Department for Foot and Ankle Surgery Rummelsberg and Nuremberg, Germany.
Background:
The purpose of this study was to compare semi-automatic software-based angular measurement (SAM) with previously validated measurement by hand (MBH) regarding angle values and time spent for the investigator for Weight-Bearing CT (WBCT).
Methods:
In this retrospective comparative study, five-hundred bilateral WBCT scans (PedCAT, Curvebeam, Warrington, PA, USA) were included in the study. Five angles (1st - 2nd intermetatarsal angle (IM), talo-metatarsal 1-angle (TMT) dorsoplantar and lateral projection, hindfoot angle, calcaneal pitch angle) were measured with MBH and SAM (Bonelogic Ortho Foot and Ankle, Version 1.0.0-R, Disior Ltd, Helsinki, Finland) on the right/left foot/ankle. The angles and time spent of MBH and SAM were compared (t-test, homoscesdatic).
Results:
The angles differed between MBH and SAM (mean values MBH/SAM; IM, 9.1/13.0; TMT dorsoplantar, -3.4/8.2; TMT lateral. -6.4/-1.1; hindfoot angle, 4.6/21.6; calcaneal pitch angle, 20.5/20.1; each p < 0.001 except the calcaneal pitch angle, p = 0.35). The time spent for MBH / SAM was 44.5 ± 12 s / 12 ± 0 s on average per angle (p < 0.001).
Conclusions:
SAM provided different angles as MBH (except calcaneal pitch angle) and can currently not be considered as validated angle measurement method (except calcaneal pitch angle). The investigator time spent is 73% lower for SAM (12 s per angle) than for MBH (44.5 s per angle). SAM might be an important step forward for 3D-angle measurement of WBCT when valid angles are provided.

