Background: Excessive laxity of the first ray has been implicated in various foot disorders. Accurate assessment is critical to define the most appropriate treatment. However, assessment currently depends largely on clinical examination and lacks objectivity. We evaluated the performance of an automated electromechanical tool developed to measure the relative dorsal mobility of the medial column compared to the lateral rays, and assessed the intra- and inter-examiner reliability of this device.
Methods: Two examiners assessed 30 feet of 17 volunteers. Data were collected 15 times on each foot. The intraclass correlation coefficient (ICC), Bland-Altman (B&A) graphical analysis, and the standard error of measurement (SEM) were calculated.
Results: Inter-rater and intra-rater ICC values (>0.9) were excellent. The Bland-Altman analysis revealed a mean bias of 0.07 mm between examiners.
Conclusion: This novel electromechanical device has demonstrated reliability in measuring first ray laxity, supporting its use in future studies aimed at quantifying first ray hyperlaxity.
Level of evidence: Level II, Prospective Reliability Study.