The Language of Anatomy
Terms, terms and more terms
Anatomy, like most of the sciences has its own language or jargon. For us to communicate effectively we all have to speak the same language and have the same frame of reference. This module will introduce you to the anatomical terms applicable to gross anatomy that you will be using this semester and probably throughout your career.
Anatomical position describes the body's position as a frame of reference. This may not seem important but when you are describing locations it does matter if the person is facing forward, to the rear or sideways. Anatomical position has been described to eliminate possible confusion. All directions/locations are given with anatomical position in mind. The body in correct anatomical position is facing forward, feet flat, arms to the sides with palms facing forward. ALL body directions and locations are given with this orientation in mind.
As a clinician you will often have to describe signs visible on your patient's body. It is important that you use the correct anatomical terms and that you reference appropriate landmarks or structures.
Body parts can be divided into two major subgroups, axial structures and appendicular structures. Axial body parts include the head, neck and trunk. The appendicular structures are the arms and legs.
The following is a list of terms taken directly from your laboratory manual. Please learn them. Most of these terms have Latin and Greek roots and may be used alone or in combination with other medically important root words. You will use them throughout your coursework.
|
Abdominal - area inferior to the ribs, anterior |
|
Inguinal - groin |
|
Acromial - pointed process of the shoulder, general shoulder region |
|
Mammary - breast |
|
Antebrachial - forearn |
|
Manus - hand |
|
Antecubital - elbow 'pit'; anterior surface of the elbow |
|
Mental - chin |
|
Axillary - armpit |
|
Nasal - nose |
|
Brachial - of the arm |
|
Oral - mouth |
|
Buccal - cheek |
|
Orbital - eye or eye socket |
|
Carpal - wrist |
|
Palmar - palm of the hand |
|
Cephalic - toward the head; head |
|
Patellar - knee cap |
|
Cervical - neck |
|
Pedal - foot |
|
Coxal - hip |
|
Pelvic - pelvis |
|
Crural - leg |
|
Pollex - thumb |
|
Digital - fingers and toes |
|
Pubic - genital region |
|
Femoral - thigh; upper leg |
|
Sternal - breastbone |
|
Fibular (peroneal) - lateral side of the leg |
|
Tarsal - ankle |
|
Frontal - forehead, over the frontal bone |
|
Thoracic - chest |
|
Hallux - big toe |
|
Umbilical - belly button |
The following is a list of terms taken directly from your laboratory manual. Please learn them. I have deleted redundant terms like brachial, which refers to both the anterior and posterior arm. Most of these terms have Latin and Greek roots and may be used alone or in combination with other medically important root words. You will use them throughout your coursework.
|
Calcaneal - heel of the foot |
|
Perineal - between the anus and the external genitalia |
|
Dorsum - posterior of back side of the body |
|
Popliteal - behind the knee |
|
Gluteal - rump or butt |
|
Sacral - posterior, between the hips, below lumbar |
|
Lumbar - lower back |
|
Scapular - shoulder blade |
|
Olecranal - posterior elbow |
|
Sural - calf or posterior surface of the leg |
|
Otic - ear |
|
Vertebral - spine, medial posterior surface of the trunk |
Many terms are used in reference to another structure or in reference to the trunk of the body. They are not absolute with regard to their meaning. Often these terms that reference orientation can be used in pairs. Superior and inferior constitute one such pair. It is correct to say, the knee is superior to the ankle. It is not correct to say the knee is superior. The knee may be superior to the ankle, but it is inferior to the hip. So always use these relative position terms appropriately by indicating the structures and positions you are referencing.
Superior and Inferior: When one structure is above another it is designated as superior. If one structure is located below another it is inferior. The nose is superior to the mouth. The mouth is inferior to the nose. These terms are most appropriately used along the vertical body line/axis.
Anterior and Posterior: Anterior means to the front and posterior means to the back. The heart is anterior to the spine but posterior to the sternum. The umbilicus is anterior to the small intestine.
Medial and Lateral: Medial means the structure is toward the midline of the body or of the organ. Lateral means away from the midline, towards the side of the body or the edge of the organ.
Cephalad, Cranial and Caudal: Cephalad and cranial both mean toward the head. Caudal means toward the tail. In humans, superior and inferior are used interchangeably with cranial and caudal.
Dorsal and Ventral: Dorsal indicates a structure toward the back, while ventral means the structure is located more toward the belly. The abdominal aorta is dorsal to the small intestine; the small intestine is ventral to the abdominal aorta.
Proximal and Distal: Proximal and distal are used only with structures of the appendages using the trunk as a reference point. Proximal indicates the structure is closer to the trunk than the referenced structure. The elbow is proximal (read to the trunk) to the wrist, i.e., the elbow is closer to the trunk than is the wrist. Conversely, the wrist is distal to the elbow, i.e., the wrist is farther away from the trunk than the elbow.
Superficial and Deep: Superficial structures are located toward the surface of the body or organ in reference to the structure being discussed. Deep structures are farther away from the surface of the body than the referenced structure. For example, when we study muscles this term we will be learning primarily superficial muscles. These are the outermost layer of muscles that you would encounter first if you were to peel away the skin. The large chest muscle underlying the mammary region is called the pectoralis major. So you could say the pectoralis major is deep to the skin of the mammary region. The pectoralis minor is deep to the pectoralis major, that is the pectoralis minor is found between the pectoralis major and the rib cage. The pectoralis major is superficial to the pectoralis minor.
It is difficult to observe and study a body or organ in its entirety. Normally we would cut the body or organ into pieces to better study its gross and microscopic structure. Being anatomists and lovers of words we need to have descriptive terms that describe how we have cut or sectioned the body, organ or structure. We describe the orientations of these cuts as imaginary surfaces or planes or sections.
Frontal or Coronal plane: Divides the body or organ into anterior and posterior sections.
Sagittal and Midsaggital plane: Saggital sections divide the body or organ into right and left sections. A midsaggital sections divides the body or organ in the middle into equal right and left halves.
Transverse plane: The transverse plane is perpendicular to the other two types of sections. It creates a superior and inferior section. These sections are cross sections of the body or organ.
A cavity is a space. That space could be filled with air or organs. Anatomists have divided the body into cavities. There are two major body cavities, the dorsal and vental cavities, and several minor body cavities, orbital, nasal, oral, middle ear, and synovial. The dorsal body cavity includes the cranial cavity (space where the brain resides) and the vertebral cavity, the space that contains the spinal cord. The major anterior body cavities are the thoracic cavity and the abdominopelvic cavity. The thoracic cavity is located superior to the diaphragm and is divided into 3 more cavities. The mediastinum is medial and contains the heart, trachea and thymus. The mediastinum is surrounded laterally by the pleural cavities which contain the lungs. The abdominopelvic cavity is inferior to the diaphragm and ventral to the dorsal cavity. This cavity can be subdivided into the abdominal and pelvic cavities. The abdominal cavity extends from the diaphragm to an imaginary line drawn between the iliac crests of the coxal bones. The pelvic cavity is the space inferior to this imaginary line.
The minor body cavities include the oral cavity (mouth), the nasal cavity, the orbital cavity (eye), middle ear cavity and the synovial cavities (spaces within synovial joints).
Membranes line cavities. If the membranes produce a watery lubricating secretion they are called serous membranes. These serous membranes typically line body cavities that do not open into the environment, like the thoracic and abdominal cavities. Mucous membranes unlike serous membranes, produce a thick, viscous secretion. Mucous membranes line cavities that do open into the environment, like the nasal cavity. Mucous plays a role in immunity.
Membranes are also named by their location. Membranes that are attached to the cavity walls, ie. line the space of the cavity are called 'parietal' membranes or the parietal serosa. So the membrane that lines the cavity wall where the lungs are located is called the parietal pleura. The membrane lining the abdominal cavity is called the parietal peritoneum or the peritoneum. The membrane lining the space around the heart is called the pericardium. Membranes attached directly to the surfaces of organs are called visceral serosa. The membrane attached directly to the surface of the lung is called the visceral pleura; the membrane attached directly to the surface of the heart is the epicardium or visceral pericardium.
The image below shows the membranes of the thoracic cavity. What type of section is this?
Quadrants and regions are important in the clinical practice of medicine. The identification and localization of signs and symptoms use regional and quadrant terminology. Please review these in your laboratory manual.
