Repeatability of a 3D multi-segment foot model during anterior and lateral step down tests

• We analyze the OFM repeatability of healthy adults during two clinical tests.
• Intra and inter examiner analysis was performed for Anterior and Lateral Step Down.
• The OFM was shown to be reproducible during functional tests.

The aim of the present study was to analyse the reproducibility of the Oxford Foot Model (OFM) when used with healthy adults during two clinical tests, i.e., the Anterior Step Down Test (SDA) and the Lateral Step Down Test (SDL). Five healthy participants (one male and four females, 10 limbs in total) with a mean age of 22.2 (19–30) years were assessed in four sessions of tests conducted at intervals of one week. Two independent examiners performed two of the sessions of each of the tests. For each session (intra-day), nine repetitions of each clinical test (SDA and SDL) were performed. After an interval of three hours, the data were collected again. The tests were conducted again after an interval of one week using the same experimental conditions. The intra- and inter-session repeatabilities of the ranges of motion of the feet were determined according to the standard error of measurement (SEM) for each examiner and for the differences between the examiners. The repeatabilities of the results were high for both of the conducted tests. The SEM results were as follows: 0.47–1.94° for the intra-examiner assessment (SDA), 0.55–2.01° for the inter-examiner comparison (SDA), 0.44–2.43° for the intra-examiner assessment (SDL), and 0.54–1.89° for the inter-examiner comparison (SDL). The OFM model was shown to be reproducible in terms of assessing the range of motion of healthy adults during functional tests (SDA and SDL).