Physical Exam: Art in Healthcare

Historical Background Jean Alexandre Barré first described a sensitive leg sign in 1919 for detecting subtle pyramidal paresis, with the patient prone and one leg flexed at the hip and knee. His 1920 paper introduced the upper limb test—arms outstretched, eyes closed, palms supinated—which later became known as Barré sign or pronator drift. Giovanni Mingazzini had described a similar arm‑drift phenomenon several years earlier, and the coexistence of these names reflects how the sign evolved within neurology. Clinical Mechanism In upper motor neuron lesions, the supinator muscles weaken more than the pronators. As a result, the affected arm gradually drifts downward and the palm turns inward. Clinicians often teach that pronation represents an evolutionarily older, subcortically driven movement pattern that emerges when pyramidal control is impaired. Diagnostic Utility Studies have shown that the pronator drift test is highly sensitive and specific for detecting mild unilateral cerebral...

Historical Background In 1889, Charles McBurney, a New York surgeon, described a “fixed point” of maximal tenderness in acute appendicitis—one-third the distance from the anterior superior iliac spine to the umbilicus on the right. Before imaging, this guided early diagnosis and surgical decisions. Clinical Mechanism Tenderness here marks the shift from vague periumbilical visceral pain to sharp somatic pain as parietal peritoneum inflames—linking appendix position, T10-L1 nerves, and referral patterns. Diagnostic Utility It remains useful in bedside composites like the Alvarado score (sensitivity 50-94%, specificity 60-90%), though imaging dominates; ideal for students to practice anatomic reasoning. Recommended Video Clear OSCE demo of McBurney palpation and guarding (3:12 min): https://www.youtube.com/watch?v=0iTMl6voJKA.   McBurney C. Experience with early operative interference in cases of disease of the vermiform appendix. Ann Surg. 1889;10:6-22.