AI Summary & Key Takeaways
AI InsightComparisons according to specialty and professional level should be interpreted as exploratory.
📌 3 Key Takeaways
Abstract
Aims: Surface-based joint localization is a fundamental component of musculoskeletal physical examination, yet its spatial accuracy relative to true anatomical joint position has not been systematically quantified across multiple joint regions under standardized conditions, with only limited evidence regarding exploratory comparisons by specialty or professional level. Methods: This cross-sectional observational study evaluated 30 physicians from physical medicine and rehabilitation (PM&R) and orthopedics. Four joint regions were assessed bilaterally on the same healthy volunteer model: tibiofemoral, humeroulnar, tibiotalar, and radiocarpal. Participants identified joint location using surface anatomical landmarks alone. Ultrasound was used to establish the reference joint position, and the spatial discrepancy between participant-marked and sonographically defined points was measured in millimeters. Results: A total of 240 localization assessments were analyzed. The lowest mean spatial discrepancy was observed at the radiocarpal joint (8.0±3.9 mm), followed by the humeroulnar joint (9.0±4.2 mm), the tibiofemoral medial joint line (11.0±4.8 mm), and the tibiotalar joint (15.0±5.6 mm). No statistically significant differences were detected according to specialty or professional level. In mixed-effects analysis, joint region remained independently associated with spatial discrepancy, with greater discrepancy observed at the tibiofemoral and tibiotalar regions. Conclusion: Measurable discrepancies were observed between clinicians’ surface-based estimations of joint location and the ultrasound-defined anatomical joint position across all evaluated regions, with the greatest discrepancy at the tibiotalar joint and the most favorable localization accuracy at the radiocarpal joint. These findings suggest that localization accuracy is influenced by joint region and that ultrasound-based feedback may be useful in musculoskeletal examination training, particularly for anatomically challenging joints. Comparisons according to specialty and professional level should be interpreted as exploratory.