Physical diagnosis has a history of more than 2,000 years since the time of Hebraides and Huangdi Neijing. With the highly developed science and technology and the increasing number of various modern medical diagnostic instruments, the traditional physical diagnostic methods seem to be out of favor, and this has led to the attachment of some physicians to instrumentation testing. However, the physical diagnostic methods we commonly use, such as sight, touch, percussion, and hearing, are the summaries of human experience formed during the diagnosis and prevention of diseases for thousands of years, and their main purpose is to discover pathological changes in patients and make diagnosis through the physician’s senses, which is the cornerstone of building a diagnostic building. Without systematic physical diagnosis, it often leads to underdiagnosis or misdiagnosis of diseases, and also greatly increases the burden of social medical care. Diabetes is a common disease that seriously affects people’s health and can be life-threatening. According to current statistics, 15% of diabetic patients will develop foot ulcers, and if amputation occurs, the 5-year survival rate for such patients is only 44%, even if regular diabetic treatment is continued. Peripheral neuropathy and vascular disease are the underlying causes of the diabetic foot, and identification and treatment of these lesions at an early stage can effectively reduce the incidence of amputation. One of the keys to reducing the rate of amputation in diabetic patients is for the internist to remove the patient’s shoes and socks and carefully examine both feet. Case 1: Li, female, 56 years old. Complaint: Diabetes mellitus for 6 years, symmetrical numbness and tingling in both lower limbs for 2 years, aggravated for 3 months. Usually treated with oral hypoglycemic drugs, with poor glycemic control. Two years ago, he developed symmetrical bilateral lower extremity tingling and numbness, but did not pay attention to it, and the above symptoms gradually worsened. In the past 3 months, he had tingling pain in both lower extremities, especially at night, and numbness in both lower extremities, walking like stepping on a cotton mat, resulting in unstable walking, accompanied by wasting, weakness and cold limbs. Laboratory tests: fasting blood glucose (FPG) 10.0 mmol/L, 2 hours postprandial glucose (2hPG) 14.1 mmol/L, glycated hemoglobin 9.4%. For such a patient, many doctors are more concerned about bringing down the patient’s blood glucose, and hospitals that have the conditions can do an electromyography to corroborate the diagnosis of diabetic peripheral neuropathy. In fact, a comprehensive physical examination can save the cost of EMG. According to statistics, 70% of diabetic patients with more than 10 years of disease have diabetic neuropathy in combination. Neuropathy is a proven risk factor for foot injury, and it is important for diabetic patients to detect the combination of neuropathy in a timely manner. Therefore, in addition to routine history taking, a careful neurological examination of the foot must be performed in these patients. The examination includes: (1) Visual examination: whether the skin color is pale or flushed, whether there is dryness, cracking and combined dermatophytosis, corpus callosum, whether there is muscle atrophy, and whether there is joint ectropion or protrusion. (2) Palpation: 5.07/10 grams of Semmes Weinstein single nylon wire to determine the sensory examination is the current international common means of evaluating foot sensation, that is, using 10 grams of nylon wire to touch the foot with a certain pressure to determine whether there is sensation in the contact area, is a simple and inexpensive method of sensory detection. If a diabetic patient cannot feel this pressure, it should be considered as protective sensory loss and should be given preventive treatment in time. Vibratory sensory testing: A 128-Hz tuning fork is placed on the bony prominence of the foot to determine whether the patient has sensation. Some prospective studies have shown that a decrease in vibriosensory perception is indicative of an impending ulcer. Skin temperature check: Qualitative determination is as simple as placing a cup of warm water, placing the tuning fork or a small stainless steel stick in the water, removing it and placing it on the skin of the patient’s skin area for him/her to feel, while comparing it to the tester’s sensation. Discernment check: A fine needle is used to carry out the check to observe the patient’s degree of location discrimination, taking care to avoid lacerating the skin. (3) Percussion: The patient is placed supine with the knee flexed and abducted, the examiner holds the patient’s toes and makes a slight dorsiflexion, and taps the Achilles tendon with a percussion hammer. Another method is that the patient kneels on a chair with both feet dangling, and the examiner uses the left hand to hold the foot in mild dorsiflexion and percuss the Achilles tendon, or sits with both feet dangling and the patient’s foot in mild dorsiflexion and percusses the Achilles tendon, the advantage of these methods is that the muscles can be easily checked and relaxed, which is conducive to the elicitation of reflexes. Patients with diabetic peripheral neuropathy usually show diminished or absent ankle reflexes. Case 2: Zhang Moumou, male, 71 years old, with a history of diabetes mellitus for 13 years and hypertension for 25 years, with poor glycemic control and blood pressure fluctuating between 140-150/70-90 mm Hg. In November 2009, he gradually developed coldness in both lower extremities, aggravated in winter, and pain in the lower extremities after activity. in February 2012, the pain in the right lower extremity worsened and became obvious at night, unrelated to activity. The outpatient physician also considered the patient to have diabetic lower extremity vasculopathy and suggested him to have vascular ultrasound, CT or MRI for clarification. Admittedly, these examinations can provide more reliable results, but they are costly and extensive vascular examinations waste the examination resources of the imaging department. If combined with simple physical diagnostic techniques it is possible to determine the degree of lower extremity ischemia and help guide the next examination. (1) Visual diagnosis: For patients considering arterial ischemia in the lower extremities, a lower extremity posture test can be performed, in which the patient’s feet are elevated on the lower extremities for 30-60 seconds if the skin appears significantly pale and the middle part of the limb is seen to be purplish-red after dropping. If the venous filling time (time for the skin of the foot to turn from pale to red) is more than 15 seconds, it means that the blood supply to that lower extremity is obviously insufficient. (2) Palpation: Arterial palpation of the lower extremity can be performed at the femoral artery, N fossa and dorsalis pedis to palpate for the presence of pulsations in the femoral artery, N artery and dorsalis pedis artery and to get a general idea of where the stenosis is occurring. Since lower extremity arterial disease is more distal and has a higher rate of amputation and death than non-diabetic patients, it is more important to detect pulsations in the dorsalis pedis artery. The dorsalis pedis artery is located on the dorsal line of the medial and lateral ankle, between the long extensor tendon of the thumb and the long extensor tendon of the toe, and is easily palpable; this palpation is not costly and is of interest in detecting diabetic lower extremity arteriopathy. A study summarized 4675 patients with type 2 diabetes who underwent palpation of the dorsalis pedis artery over a 10-year period and found 1,164 cases (24.9%) of abnormal pulsations in the dorsalis pedis artery. On the other hand, the degree of systemic atherosclerosis can be understood by the pulsation of the dorsalis pedis artery in the lower extremities, and patients with abnormal arterial pulsation in the lower extremities have a higher risk of cardiovascular and cerebrovascular disease. The literature reports that patients with peripheral arterial disease requiring surgical treatment have a 90% incidence of coronary stenosis when they undergo coronary angiography, with 28% of these patients having severe three-branch disease. The incidence of lower extremity arterial disease increases with age and duration of disease, and nearly half of diabetic patients older than 70 years and with disease duration of more than 20 years have dorsalis pedis artery abnormalities on palpation, and the rate of abnormalities increases significantly after 10 years of disease duration, with almost half of patients having dorsalis pedis artery abnormalities after 20 years. The risk of macroangiopathy should be given high priority in patients with diabetes mellitus more than 10 years old. The guidelines recommend that all adult diabetic patients should undergo a comprehensive foot examination at least once a year. If the dorsalis pedis artery is found to be weakened or even absent, timely guidance and treatment should be given to prevent foot ulcers in these patients, and anti-atherosclerotic treatment should be strengthened to reduce the occurrence of cardiovascular and cerebrovascular events. With the rapid development of medicine, various advanced experimental diagnostic and imaging technologies have been introduced, which have greatly improved the level of diagnosis. However, from the perspective of evidence-based medicine, the clinical use of adjuvant diagnostic techniques is still highly discretionary. Excessive application of ancillary tests will inevitably lead to a rapid increase in medical costs, which not only increases the burden on patients, but is also extremely detrimental to the long-term development of medical care. Diabetologists should firmly grasp the idea of evidence-based physical diagnostics. Regardless of whether the condition is complex or simple, history and signs are the first step in diagnosis. Most common diseases can be diagnosed by a simple history and physical examination and do not necessarily require expensive tests. For complex and difficult diseases, history and physical examination can help clinicians form an initial impression of the diagnosis and narrow the differential diagnosis, even if the diagnosis cannot be confirmed. On the basis of this, targeted laboratory tests can often be performed, often with half the effort.