Gray’s Basic Anatomy 2nd Edition

Book Preface

Gray’s Basic Anatomy was developed in response to students and colleagues from around the world who requested a more concise description of anatomy than that presented in Gray’s Anatomy for Students. To accomplish this goal, we reworked the material to focus mainly on regional anatomy and integrated the clinical material, imaging, and surface anatomy information directly into the text as:
• Clinical apps, which give students context for why a strong anatomical background helps facilitate the solving of clinical problems;
• Imaging apps, which offer students a great introduction to the different techniques and modalities available for imaging relevant anatomy; and
• Surface anatomy boxes, which help students visualize the relationship between anatomical structures and surface landmarks necessary for any kind of patient examination.

In addition, at the beginning of each chapter students are directed to additional learning resources available on Student Consult (Elsevier’s online educational website). Summarizing, Gray’s Basic Anatomy uses a regional approach, similar to Gray’s Anatomy for Students, with eight chapters: The Body, Back, Thorax, Abdomen, Pelvis and Perineum, Lower Limb, Upper Limb, and Head and Neck. The artwork presents the same familiar illustrations from Gray’s Anatomy for Students, but they have been resized to t within a smaller format while retaining a close physical location to the text with which each gure is associated. Finally, while some verbiage has been sacri ced in keeping with the goal of presenting a concise textbook of anatomy (e.g., muscle descriptions have for the most part been incorporated into tables with no loss of content), additional clinical and imaging material has been added to enhance learning in context.

This second edition includes numerous edits resulting from reader feedback, some new and revised gures, and revisions based on current research in the eld of the anatomical sciences.

We hope you will continue to nd this new edition a useful and valuable resource whether you are an educator or a student.
Richard L. Drake
A. Wayne Vogl
Adam W.M. Mitchell

What is anatomy?

Anatomy includes those structures that can be seen grossly (without the aid of magni cation) and microscopically (with the aid of magni cation). Typically, when used by itself, the term anatomy tends to mean gross or macroscopic anatomy—that is, the study of structures that can be seen without using a microscopic. Microscopic anatomy, also called histology, is the study of cells and tissues using a microscope.

Observation and visualization are the primary techniques a student should use to learn anatomy. Anatomy is much more than just memorization of lists of names.
Although the language of anatomy is important, the network of information needed to visualize the position of physical structures in a patient goes far beyond simple memorization. Knowing the names of the various branches of the external carotid artery is not the same as being able to visualize the course of the lingual artery from its origin in the neck to its termination in the tongue. An understanding of anatomy requires an understanding of the context in which the terminology can be remembered.

HOW CAN GROSS ANATOMY BE STUDIED?

The term anatomy is derived from the Greek word temnein, meaning “to cut.” Clearly, at its root, the study of anatomy is linked to dissection. Dissection of cadavers by students is now augmented, or even in some cases replaced, by viewing prosected (previously dissected) material and plastic models, or using computer teaching modules and other learning aids.

Anatomy can be studied following either a regional or a systemic approach.
■ With a regional approach, each region of the body is studied separately and all aspects of that region are studied at the same time. For example, if the thorax is to be studied, all of its structures are examined. This includes the vasculature, nerves, bones, muscles, and all other structures and organs located in the region of the body de ned as the thorax. After studying this region, the other regions of the body (i.e., the abdomen, pelvis, lower limb, upper limb, back, head, and neck) are studied in a similar fashion.
■ In contrast, in a systemic approach, each system of the body is studied and followed throughout the entire body. For example, a study of the cardiovascular system looks at the heart and all of the blood vessels in the body. This approach continues for the whole body until every system, including the nervous, skeletal, muscular, gastrointestinal, respiratory, lymphatic, and reproductive systems, has been studied.

IMPORTANT ANATOMICAL TERMS

The anatomical position
The anatomical position is the standard reference position of the body used to describe the location of structures (Fig. 1.1). The body is in the anatomical position when standing upright with feet together, hands by the side, and face looking forward. The mouth is closed and the facial expression is neutral. The rim of bone under the eyes is in the same horizontal plane as the top of the opening to the ear, and the eyes are open and focused on something in the distance. The palms of the hands face forward with the ngers straight and together and with the pad of the thumb turned 90° to the pads of the ngers. The toes point forward.

Anatomical planes
Three major groups of planes pass through the body in the anatomical position (Fig. 1.1).
■ Coronal planes are oriented vertically and divide the body into anterior and posterior parts.
■ Sagittal planes also are oriented vertically, but are at right angles to the coronal planes and divide the body into right and left parts. The plane that passes through the center of the body dividing it into equal right and left halves is termed the median sagittal plane.
■ Transverse, horizontal, or axial planes divide the body into superior and inferior parts.