Ultrasonography (US) is a versatile modality in clinical practice. US yields anatomical and physiological information about the whole body at the bedside. The concept of point-of-care ultrasonography (POCUS) has been widely accepted owing to the development of portable US systems and accumulated evidence concerning its utility in many clinical settings and in all phases of care [1]. It is no exaggeration to say that POCUS deserves to be one of the basic skills for physicians, alongside history taking and physical examinations, for example. On top of that, it is reasonable to suggest that training to use this modality be globally included in undergraduate medical education [2].

A large body of educational literature shows that training medical students to perform US is expected to facilitate the study of basic subjects, such as anatomy and physiology, improve the efficiency of physical examinations, and aid them in acquiring diagnostic and procedural skills [2,3,4]. Interestingly, the real-time visual feedback that US provides increases their motivation to learn [3, 5]. On learning physical examination skills with US, several studies indicate improvement in their palpation skill of the liver [6], femoral artery [7], and musculoskeletal system [8, 9] as a result of the real-time feedback. However, its addition as an educational tool may not actually help them if they are overwhelmed with the heavy cognitive load of learning physical examinations and US simultaneously [10, 11]. Medical students may need to be trained in basic US knowledge and skills before they effectively learn physical examination skills using US in clinical clerkship [2, 12, 13]. Alternatively, they may need to reach a minimum level of competence in performing physical examinations before they are able to benefit from the feedback from US [2, 14].

Based on my experience as an educator of US and emergency medicine, medical students who obtain basic physical examination skills before clinical clerkship seem to receive more educational benefits from the combination of physical examination and US. Under supervision, they detected a swollen leg via visual inspection followed by a thrombus in the femoral vein with POCUS. They detected gallop rhythm with auscultation followed by severely reduced left ventricular systolic function with POCUS. They detected the Murphy sign in palpation followed by a swollen gallbladder and sonographic Murphy sign. I realized that they really appreciated the education, especially when they identified such abnormal findings with physical examinations and then detected corresponding findings with POCUS by themselves. It seems that providing these experiences increases their motivation to learn both physical examinations and POCUS.

Over the decades, the widespread availability of medical imaging modalities such as US and CT has decreased physicians’ reliance on physical examinations for establishing diagnoses and reduced their confidence in their physical examination skills [14]. The advent of POCUS has caused some anxiety that it was meant to replace physical examinations, while physical examinations cannot and must not be replaced by POCUS [15]. POCUS is essentially a focused examination, and it can be performed properly by aiming the targets correctly based on the clinical context consisting of the patient’s history, vital signs, and physical examinations. Before performing POCUS, a hypothesis or differential diagnosis is formulated with the clinical context by intuitive, inductive, and/or deductive approaches. While performing POCUS to acquire anatomical and physiological findings, physicians sometimes confirm the accuracy of their physical examinations and take additional patient history based on the real-time visual feedback. The hypothesis is generally verified by the deductive approach with POCUS. Figure 1 shows the model of the clinical reasoning including POCUS [16].

Fig. 1
figure 1

The model of clinical reasoning including point-of-care ultrasonography (POCUS). This figure is a revision of Fig. 1 in Jpn J Med Ultrasonics 2019; 46: 5–15

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Getting back to the subject of undergraduate medical education, in my opinion, education with the combination of physical examination and POCUS during clinical clerkship is one of the keys to preserving the art of physical examinations and developing POCUS in the future of medicine. It is reasonable to learn basic physical examination and US skills with models in advance to reduce the cognitive load when medical students learn the applied skills in the clinical clerkship. Seeing pathology through POCUS under the guidance of physical examinations can improve interest in both physical examinations and POCUS among medical students. Awareness of the clinical reasoning including the combination of physical examinations and POCUS may help both learners and educators to achieve success in bedside learning and teaching. I believe the combination can create a synergistic effect in undergraduate medical education and result in enhanced clinical utility.