Introduction
Surface anatomy is defined as to outline the organs and important internal structures on the surface of the body. The surface anatomy is very much essential because the body cannot be opened everytime, a diagnosis of a disease needs to be done as to which organ is affected. Surface anatomy knowledge enables the clinician to assess the internal organs from the surface by clinical examination. Hence, surface anatomy though neglected has to be given more importance as it is widely used by the clinicians. The knowledge is useful during feeling of pulse, measurement of blood pressure, hearing heart and breathing sounds, identification of organomegaly, incision and drainage, aspirations like lumbar puncture and many more.
Anatomical Position of the Human Body
This is described as the human body standing upright with the hands supinated and the feet resting on the ground completely. In this position, all the joints are in extended position and the eyes looking straight forward. The upper limbs are dropping down in adducted position as shown in Figure 1.1. The lower limbs are placed at 1-foot width with the toes directed forward.
Thus, the anatomical position is defined as “body in erect posture, with upper limbs on the sides, with palms and feet directed forward and eyes directed toward the horizon”.
The position is important to know as all the planes and imaginary lines are drawn in this anatomical position and used as universal reference.
The surface anatomy of every structure and organ is drawn on the surface of the human bodies keeping the anatomical position in mind.
There are four main methods of clinical examination of any organ system in general (except nervous system, which is different). These are as follows:
- Inspection: Visual screening of the surface area concerned for the usual normal structures or to look for any visible abnormalities (e.g. abnormal swellings, dilated veins).
- Palpation: Feeling for the underlying organ or abnormality (e.g. palpation for liver, spleen, palpation of any swellings on the limbs or the body).
- Percussion: Percuss for any organ enlargement or pathology specifically on the surface of the thorax or abdomen (e.g. percussion of liver, gas or fluid in abdomen, heart borders).
- Auscultation: Listen to normal physiological sounds or abnormal sounds with a stethoscope (e.g. heart sounds, lung sounds).
All these require a sound knowledge of surface anatomy, because as the saying goes “the eyes can see only what the mind knows”.