The impact on anatomical landmark identification after an ultrasound-guided palpation intervention: a pilot study

BACKGROUND: To determine whether a discrepancy exists in identifying three musculoskeletal landmarks (medial meniscus, lateral malleolus and lateral epicondyle of the humerus) and whether ultrasound-guided (US-guided) palpation intervention can reduce that discrepancy and improve localization for chiropractic interns. METHODS: Sixteen chiropractic interns were asked to identify three subcutaneous anatomical landmarks before/ after the intervention and at a 3-day follow-up. The intervention was a three-minute US-guided demonstration of the landmarks after the intern’s initial localization. The primary outcome measure was the change in distance between the intern’s landmark identification. Non-normal data were analyzed with the Friedman’s and Wilcoxon signed rank tests. Discrepancy between examiner-determined landmarks and intern-identified landmarks at the initial time point was assessed with a 1-sample Wilcoxon signed rank test. RESULTS: All locations demonstrated an initial discrepancy between examiner-determined landmarks and intern-identified landmarks at the initial time point. Overall, a statistically significant difference was noted in the identification of the medial meniscus (p = 0.012) and lateral malleolus (p = 0.001), but not at the lateral epicondyle (p = 0.086). For the before and immediately after comparison, a significant improvement was found with the medial meniscus (p = 0.005) and lateral malleolus (p = 0.002). The 3-day post-intervention comparison found an improvement only for the lateral malleolus (p = 0.008). CONCLUSION: This pilot study demonstrated palpatory discrepancy at identifying all three landmarks. Our data suggests that US-guided palpation intervention seems to improve an intern’s ability to palpate two landmarks (medial meniscus and lateral malleolus) post-intervention.