Natomy And Physiol

Study the anatomy of the chest wall, identifying the structures illustrated. Note that an interspace between two ribs is numbered by the rib above it.

Rib Interspaces

Locating Findings on the Chest. Describe abnormalities of the chest in two dimensions: along the vertical axis and around the circumference ofthe chest.

To make vertical locations, you must be able to count the ribs and interspaces. The sternal angle, also termed the angle of Louis, is the best guide: place your finger in the hollow curve of the suprasternal notch, then move your finger down about 5 cm to the horizontal bony ridge joining the manubrium to the body of the sternum. Then move your finger laterally and find the adjacent 2nd rib and costal cartilage. From here, using two fingers, you can "walk down the interspaces," one space at a time, on an oblique line illustrated by the red numbers below. Do not try to count interspaces along the lower edge of the sternum; the ribs there are too close together. In a woman, to find the interspaces either displace the breast laterally or palpate a little more medially than illustrated. Avoid pressing too hard on tender breast tissue.

Rib Laterally

Note that the costal cartilages of the first seven ribs articulate with the sternum; the cartilages of the 8 th, 9th, and 10 th ribs articulate with the costal cartilages just above them. The 11th and 12th ribs, the "floating ribs," have no anterior attachments. The cartilaginous tip of the 11th rib can usually be felt laterally, and the 12th rib may be felt posteriorly. On palpation, costal cartilages and ribs feel identical.

Posteriorly, the 12 th rib is another possible starting point for counting ribs and interspaces: it helps locate findings on the lower posterior chest and provides an option when the anterior approach is unsatisfactory. With the fingers of one hand, press in and up against the lower border of the 12th rib, then "walk up" the interspaces numbered in red below, or follow a more oblique line up and around to the front of the chest.

The inferior tip of the scapula is another useful bony marker—it usually lies at the level of the 7th rib or interspace.

7th Interspace Inferior Axillary

The spinous processes of the vertebrae are also useful anatomic landmarks. When the neck is flexed forward, the most protruding process is usually the vertebra of C7. If two processes are equally prominent, they are C7 and T1. You can often palpate and count the processes below them, especially when the spine is flexed.

To locate findings around the circumference of the chest, use a series of vertical lines, shown in the next three illustrations. The midsternal and vertebral lines are precise; the others are estimated. The midclavicular line drops vertically from the midpoint of the clavicle. To find it, you must identify both ends of the clavicle accurately (see p. 469). The anterior and posterior axillary lines drop vertically from the anterior and posterior axillary folds, the muscle masses that border the axilla. The midaxillary line drops from the apex of the axilla.

Midsternal line

Midclavicular line

Anterior axillary line

Midsternal line

Midclavicular line

Anterior axillary line

Midsternal Line Vertebral Line

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  • teija palo
    How to count ribs in physical examination?
    8 years ago
  • beatrice
    Does the costal cartilage of the 1st rib articulate with the clavicle?
    8 years ago
  • lyyli viitala
    How to palpate spinous process of t1?
    8 years ago
  • Linda
    Where is interspace in anatomy?
    8 years ago
  • hazel
    What are the effects of a costal cartilage?
    8 years ago
  • Sirpa
    How are human ribs numbered?
    8 years ago
  • alessia
    Which is the rib protruding below breast?
    8 years ago
  • Longo
    Where are ribs locate?
    8 years ago
  • david
    How to identify 7th rib by physical exam?
    6 years ago
  • ROMA
    How to count ribs chest examination?
    5 years ago
  • ella
    How to count the ribs on physical exam?
    5 years ago
  • michael
    How to find midclavicular line?
    5 years ago
  • edoardo
    How to locate the 9th interspace on the posterior axilliary line?
    4 years ago
  • giancarlo
    Why is it that anterior ribs is more accurate more than posterior ribs in counting?
    4 years ago
  • tanta
    How to count the ribs anterior ribs and posterior ribs anatomy?
    4 years ago
  • teodros
    How long does a chest wall take to heal?
    4 years ago
  • Swen
    How to count ribs on pateint?
    2 years ago
  • joseph
    How to describe rib clicking on physical exam?
    6 months ago
  • Jolanda
    How to count rib at the midaxillary line?
    2 months ago
  • orgulas
    How to count ribs on physicalexam?
    2 months ago
  • Brutus
    What muscles connect to the sternum?
    1 month ago

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