Chapter 4 Flashcards
The bones of the upper limb can be divided into four main groups:
(1) hand and wrist, (2) forearm, (3) arm (humerus), and (4) shoulder girdle
__ bones in each hand and wrist
The 27
How many bones are in the Phalanges (fingers and thumb)
14
How many bones in the Metacarpals (palm)
5
How many bones are Carpals (wrist)
8
The most distal bones of the hand are the,
phalanges (fa-lan-jez)
The second group of bones is the metacarpals (met*-ah-kar-palz); these bones make up the __ of each hand.
palm
The third group of bones, the carpals (kar-palz), consists of the bones of the
wrist
Each finger and thumb is called a digit, and each digit consists of two or three separate small bones called
phalanges
The digits are numbered, starting with the thumb as __ and ending with the little finger as __
Thumb as 1
Little finer as 5
Each of the four fingers (digits 2, 3, 4, and 5) is composed of three phalanges
proximal, middle, and distal.
The thumb, or first digit, has two phalanges
proximal and distal.
Each phalanx consists of three parts:
distal rounded head, a body (shaft), and an expanded base,
The second group of bones of the hand, which make up the palm, consists of the five
metacarpals.
metacarpal bones are numbered the same way as the digits are, with the first metacarpal being on the
thumb, or latera, side when the hand is in the anatomic position.
Each metacarpal is composed of three parts, similar to the pha-langes. Distally, the __.
rounded portion is the head
Each metacarpal is composed of three parts, similar to the pha-langes. The body (shaft) is the long, curved portion; the anterior part
is concave in shape, and the posion or dorsal, portion is convex.
Each of the second through fifth digits has three phalanges, and they have three joints each. Starting from the most distal portion of each digit, the joints are the ___ followed by the __, and, most proximally, the
distal interphalangeal (DIP) joint,
proximal interphalangeal (PIP) joint
MCP joint.
The metacarpals articulate with the phalanges at their distal ends and are called __ joints.
metacarpophalangeal (MCP)
At the proximal end, the metacarpals articulate with the respective carpals and are called __ joints.
carpometacarpal (CMC)
The five metacarpals articulate with specific carpals as follows:
• First metacarpal with __
• Second metacarpal with __
• Third metacarpal with __
• Fourth and fifth metacarpal with __
trapezium
trapezoid
capitate
hamate
For carpals beginning on the lateral, or thumb, side is the
scaphoid (skaf-oyd, sometimes referred to as the navicular.
The scaphoid, a boat-shaped bone, is the largest bone in the proximal row and articulates with the
radius proximally
Its location and articulation with the forearm make it important radiographi-cally because it is the most frequently fractured carpal bone.
The scaphoid
is the second carpal in the proximal row; it articulates with the radius.
The lunate (moon shaped)
The lunate (moon shaped) is the second carpal in the proximal row; it articulates with the
radius
The third carpal is the __, which has three articular surfaces and is distinguished by its pyramidal shape and anterior articulation with the small pisiform.
triquetrum (tri-kwe-trum)
The third carpal is the triquetrum (tri-kwe-trum), which has three articular surfaces and is distinguished by its __ and anterior articulation with the small pisiform.
pyramidal shape
The third carpal is the triquetrum (tri-kwe-trum), which has three articular surfaces and is distinguished by its pyramidal shape and anterior articulation with the
small pisiform.
The __, the smallest of the carpal bones, is located anterior to the triquetrum and is most evident in the carpal canal or tangential projection (Fig. 4.7).
pisiform (pi-si-form) (pea shaped)
The pisiform (pi-si-form) (pea shaped), the smallest of the carpal bones, is located anterior to the __and is most evident in the carpal canal or tangential projection (Fig. 4.7).
triquetrum
For the distal row in carpals on the lateral, or thumb, side is the
trapezium
the trapezium (trah-pe-ze-um), a four-sided, irregularly shaped bone that is located medial and distal to the __ and proximal to the first __.
scaphoid
metacarpal
wedge-shaped __, also four sided, is the smallest bone in the distal row.
trapezoid (trap’-e-zoyd)
This bone is followed by the largest of the carpal bones, the
capitate
the capitate is identified by its large rounded head that fits proximally into a concavity formed by the __ bones.
scaphoid and lunate
The last carpal in the distal row on the medial aspect is the __, which is easily distinguished by the hooklike process called the __, which projects from its palmar surface (see Fig. 4.7).
hamate (ham’-ate
hamulus (ham-u-lus), or hamular process
This concave area or groove is called the carpal sulcus (carpal tunnel or canal), through which __pass.
major nerves and tendons
The term __ means hooked, which describes the shape of the bone
hamate
The anteriorly located pisiform and the hamulus process of the hamate are visualized best on this view.
Tangential view
In the lateral position , the __ are located more anteriorly.
trapezium and scaphoid
In a lateral position the ulnar deviation projection best demonstrates the __ without the foreshortening and overlapping seen on the posteroanterior (PA)
scaphoid
The second group of upper limb bones consists of the bones of the forearm-the
radius on the lateral or thumb side and the ulna on the medial side
The radius and ulna articulate with each other at the __ and __ joints,
proximal radioulnar joint and at the distal radio-ulnar
proximal radioulnar joint and at the distal radio-ulnar joint, These two joints allow for the rotational movement of the
wrist and hand,
Small conical projections, called styloid processes, are located at the
extreme distal ends of both the radius and the ulna
is a small depression on the medial aspect of the distal radius.
ulnar notch
fits into the ulnar notch to form the distal radioulnar joint.
The head of the ulna
The head of the ulna is located
near the wrist at the distal end of the ulna.
The head of the radius is located at the
proximal end of the radius near the elbow joint.
The long midportion of both the radius and the ulna is called the
body (shaft).
___, the shorter of the two bones of the forearm, is the only one of the two that is directly involved in the wrist joint.
The radius
The rough oval process on the medial and anterior side of the radius, just distal to the neck, is the
radial tuberosity.
__, the longer of the two bones of the fore-arm, is primarily involved in the formation of the elbow joint.
The ulna
The two beaklike processes of the proximal ulna are called the
olecra-non and the coronoid processes
The olecranon process can be palpated easily on the
posterior aspect of the elbow joint.
The large concave depression, or notch, that articulates with the distal humerus is the
trochlear (trok-le-ar) notch (semilunar notch).
The small, shallow depression located on the lateral aspect of the proximal ulna is the
radial (ra-de-al) notch.
The head of the radius articulates with the ulna at the radial notch, forming the
proximal radioulnar joint.
the proximal radioulnar joint that combines with the distal radioulnar joint to allow rotation of the
forearm during pronation.
During the act of pronation, the radius crosses over the ulna near the
upper third of the forearm (see Fig. 4.25).
The body (shaft) of the humerus is the long center section, and the expanded distal end of the humerus is the
humeral condyle.
The articular portion of the humeral condyle is divided into two parts:
the trochlea (medial condyle) and the capitu-lum
The trochlea (meaning “pulley”) is shaped like a pulley or spool; it has two rimlike outer margins and a smooth depressed center portion called the
trochlear sulcus, or groove.
This depression of the trochlea, which begins anteriorly and continues inferiorly and posteriorly, appears __ on a lateral end-on view; on a lateral elbow radiograph, it appears as a __
circular
less dense
The trochlea is located more medially and articulates with the.
ulna
The capitulum, meaning “ittle head,” is located on the lateral aspect and articulates with the head of the
radius.
is the small projection on the lateral aspect of the distal humerus above the capitulum.
The lateral epicondyle
is larger and more prominent than the lateral epicon-dyle and is located on the medial edge of the distal humerus.
The medial epicondyle
The distal humerus has specific depressions on both anterior and posterior surfaces. The two shallow anterior depressions are the
coronoid fossa and the radial fossa
The deep posterior depression of the distal humerus is the
olecranon fossa
The olecranon process of the ulna fits into this depression when the arm is fully extended.
olecranon fossa
accurate lateral with 90° flexion, along with possible associated visualization of __, are essential for evaluation of joint pathology of the elbow.
fat pads
good criterion by which to evaluate a true lateral position of the elbow when it is flexed 90° is the appearance of the
three concentric arcs
For a true lateral elbow the first and smallest arc is the
trochlear sulcus
For a true lateral elbow, the second, intermediate arc appears double lined as the outer ridges or rounded edges of the
capitulum and trochlea.’ (The smaller of the double-lined ridges is the capitulum; the larger is the medial ridge of the trochlea.)
of the ulna appears as a third arc of a true lateral elbow.
The trochlear notch
All joints of the upper limb as described in this chapter are classified as
synovial and are freely movable, or diarthrodial.
distally with the phalanges, all IP joints are ginglymus, or hinge-type, joints with movement in
two directions only-flexion and extension
This movement occurs in one plane only, around the transverse axis.
IP joints are ginglymus, or hinge-type, joints with movement in two directions only-flexion and extension
The second to fifth MCP joints are ellipsoidal (condyloid)-type joints that allow movement in
four directions-flexion, extension, abduction, and adduction.
The first MCP joint (thumb) also is generally classified as an ellipsoidal (condyloid) joint, although it has
limited abduction and adduction movements because of the wider and less-rounded head of the first metacarpal
The first CMC joint of the thumb is a saddle (sellar)-type joint, which allows a great range of movement, including
flexion, extension, abduction, adduction, cir-cumduction, opposition, and some degree of rotation.
first CMC joint of the thumb is a saddle (sellar)-type joint. This joint best demonstrates the shape and movement of a saddle joint, which allows a great range of movement, including
first CMC joint of the thumb is a saddle (sellar)-type joint. This joint best demonstrates the shape and movement of a saddle joint, which allows a great range of movement, including flexion, extension, abduction, adduction, cir-cumduction, opposition, and some degree of rotation.
The second through fifth CMC joints are __ joints, which allow the least amount of movement of the synovial class joints.
plane (gliding)-type
The intercarpal joints between the various carpals have only a __ movement.
plane (gliding)
The wrist joint is an __ joint and is the most freely movable, or diarthrodial, of the synovial classification.
ellipsoidal (condyloid)-type
Of the two bones of the forearm, only the radius articulates directly with two carpal bones-the
scaphoid and the lunate.
This wrist joint is called the
radiocarpal joint.
The articular disk is part of the total wrist articulation, including a joint between the distal radius and ulna of the forearm __joint.
the distal radioulnar
The total wrist joint is enclosed by ___ that is strengthened by ligaments that allow movement in four directions, plus circumduction.
an articular synovial capsule
ligament is attached to the styloid process of the ulna and fans out to attach to the triquetrum and the pisiform.
The ulnar collateral
extends from the styloid process of the radius primarily to the lateral side of the scaphoid (scaphoid tubercle), but it also has attachments to the trapezium.
The radial collateral ligament
stabilizes the union between the lunate and scaphoid, which is best demonstrated with the PA clenched wrist position.
The scapulolunate ligament
The elbow joint generally is considered a__ joint with flexion and extension movements between the humerus and the ulna and radius.
ginglymus (hinge)-type
In addition to the hinge joints between the humerus and ulna and the humerus and radius, the __ is considered part of the elbow joint
proximal radioulnar joint (pivot or trochoidal type)
The ulnar deviation movement of the wrist “opens up” and best demonstrates what carpals on the opposite side (
scaphoid, trapezium, and trapezoid.
Because the scaphoid is the most frequently fractured carpal bone, this ulnar deviation projection is commonly known as a
special scaphoid projection
radial deviation movement that opens and best demonstrates the carpals on the opposite, or ulnar, side of the wrist-the
hamate, pisiform, trique-trum, and lunate.
Why must the forearm routinely be radiographed in an AP projection with the hand supinated, or palm up (anatomic position).
“cross-over” position of the radius and ulna when the hand is pronated
radius and ulna can be separated through
lateral rotation
(40-45°) of the elbow,
This relationship is crucial in evaluation of AP projections of the elbow; lateral rotation __ and medial rotation __ the proximal radius and ulna.
separates
superimposes
fat pads are__ but are located within the joint capsule.
extrasynovial (outside the synovial sac)
The wrist joint includes two important fat stripes. First, a scaphoid fat stripe (A) is visualized on the __ projections.
PA and oblique
The wrist joint includes two important fat stripes. First, a __ is visualized on the PA and oblique projections.
scaphoid fat stripe (A)
what fat stripe is elongated and slightly convex in shape and is located between the radial collateral ligament and adjoining muscle tendons immediately lateral to the scaphoid.
a scaphoid fat stripe
A second fat stripe is visualized on the lateral view of the wrist. is normally visualized approximately ¼ inch (1 cm) from the anterior surface of the radius
This pronator fat stripe (B)
The three significant fat pads or stripes of the elbow are visualized only on the __ projection
lateral projection.
the lateral projec-tion, the __ fat pad, which is formed by the superimposed coronoid and radial pads, is seen as a slightly radio-lucent teardrop shape located just anterior to the distal humerus.
anterior fat pad
three significant fat pads or stripes of the elbow
Anterior posterior supinator fat pad
The __ fat stripe (Fig. 4.32E) is a long, thin stripe just anterior to the proximal radius.
supinator fat stripe
__ fat stripe that may indicate the diagnosis of radial head or neck fractures that are not obviously apparent. 3
supinator fat stripe
CAST CONVERSIONS
•Small to medium dry plaster cast:
•Large or wet plaster cast:
•Fiberglass cast:
•Small to medium dry plaster cast: +5-7 kV
•Large or wet plaster cast: +8-10 kV
•Fiberglass cast: +3-4 kV
