Image Analysis Upper Extremity

How much of the radial head should be superimposing the ulna for an AP FOREARM projection?

1/8

How much of the radial head superimposes the ulna for the AP ELBOW projection?

1/8th of radial head. About .25"

How does elbow flexion for an AP ELBOW affect the visualization of anatomical structures?

Flexion of the elbow joint on an AP elbow projection foreshortens elbow structures and draws the olecranon process from the olecranon fossa.

What is the consequence for the CR not being directed to the elbow joint? Radial head related:

Poor CR placement also foreshortens the radial head, causing its articulating surface to be demonstrated.

What is the relationship between the joints of the finger and the CR?

CR should be perpendicular and centered the PIP joint or joint of interest.

Where should the radial tuberosity be visualized for the AP ELBOW projection?

Radial tuberosity is in profile medially

What is the relationship between the distal capitulum and medial trochlea on a LATERAL ELBOW projection? If there is a misalignment, what is the exact cause?

Should be superimposed. -Proximal humerus depression and elevation determines the distal alignment of the capitulum and medial trochlea.

NEW EVALUATION CRITERIA Hand PA

-Soft tissue outlines of the second through fifth phalanges are uniform. • Distance between the MC heads is equal. • Equal midshaft concavity is seen on both sides of the phalanges and MCs of the second through fifth fingers. • Thumb demonstrates a 45-degree PA oblique projection • There is no soft tissue overlap from adjacent fingers. • Thumb is in close proximity to hand • IP, MCP, and CM joints are demonstrated as open spaces. • Phalanges are demonstrated without foreshortening • Third MCP joint is at the center of the exposure field. • Phalanges, MCs, carpals, and 1 inch (2.5 cm) of the distal radius and ulna are included within the exposure field.

NEW EVALUATION CRITERIA Finger PA

-Soft tissue width and midshaft concavity are equal on both sides of phalanges -There is no soft tissue overlap from adjacent digits. -IP and MCP joints are demonstrated as open spaces. • Phalanges are seen without foreshortening -PIP joint is at the center of the exposure field. -Finger and half of the MC are included within the exposure field.

NEW EVALUATION CRITERIA Finger Lateral

-There is no overlap from adjacent fingers -Anterior surface of the middle and proximal phalanges demonstrate midshaft concavity and the posterior surfaces show slight convexity. • More than twice as much soft tissue width is demonstrated on the anterior surface than the posterior surface -IP joints are demonstrated as open spaces. • Phalanges are not foreshortened. -PIP joint is at the center of the exposure field. -Entire finger and MC head are included within the exposure field.

NEW EVALUATION CRITERIA Finger Oblique

-Twice as much soft tissue width is demonstrated on one side of the phalanges as on the other side. • More concavity is seen on one aspect of the phalangeal midshafts than the others -There is no overlap from adjacent fingers -IP and MCP joints are demonstrated as open spaces. • Phalanges are not foreshortened -PIP joint is at the center of the exposure field. -Finger and half of the MC are included within the exposure field.

NEW EVALUATION CRITERIA Wrist Oblique

-Ulnar styloid is in profile medially • Long axes of the third MC and the midforearm are aligned. • Lunate midpoint is positioned distal to the radioulnar articulation • Radioscaphoid and radiolunate joints are closed. • Anterior and posterior margins of the distal radius are not superimposed. • Posterior radial margin superimposes no more than one fourth of the lunate • Second CM and the scaphotrapezial joint spaces are demonstrated as open spaces • Trapezoid and trapezium are demonstrated without superimposition. • Trapeziotrapezoidal joint space is open. • Trapeziocapitate joint space is closed. • Fourth and fifth MC midshafts demonstrate a small separation between them • Carpal bones are at the center of the exposure field. • Carpal bones, one fourth of the distal ulna and radius, and half of the proximal MCs are included within the exposure field.

NEW EVALUATION CRITERIA' Wrist PA

-Ulnar styloid is in profile medially • Scaphoid fat stripe is demonstrated • Radial styloid is in profile laterally. • Radioulnar articulation is open. • Superimposition of the MC bases is limited • Radioscaphoid and radiolunate joints are closed. • Anterior and posterior margins of the distal radius are not superimposed. • Posterior radial margin superimposes no more than one fourth of the lunate • Second through fifth CM joint spaces are open • Long axes of the third MC and the midforearm are aligned. • Lunate midpoint is positioned distal to the radioulnar articulation • First MC is seen without second MC superimposition • Carpal bones are at the center of the exposure field. • Carpal bones, one fourth of the distal ulna and radius, and half of the proximal MCs are included within the exposure field.

How much of the distal radius and ulna must be visualized for ALL HAND projections?

1"

What is the degree of tube angulation needed for the ULNAR DEVIATION projection if the patient is able to fully deviate?

15º towards elbow

What positioning modifications should be made for the PA WRIST projection on a patient with a thick proximal forearm?

Allowing the proximal forearm to hang off the IR or imaging table so it brings the forearm parallel to IR

How should the anterior surfaces of the capitulum and medial trochlea be visualized on a LATERAL HUMERUS projection?

Anterior surfaces of the capitulum and medial trochlea are nearly aligned.

How will you achieve 90 degrees when positioning your patients?

Being on the same plane and don't rely at looking at the shadow

How should the metacarpal heads be visualized on a PA HAND projection?

Distance between the metacarpal heads should be equal

How does the relationship between the radius and ulna differ if the patient's humerus elevated or depressed for the LATERAL FOREARM projection? This meaning is positioned so that the humerus is not positioned in the same plane as the forearm. Elevated humerus:

Elevated Humerus: More superimposition of radial head on ulna.

When patients have a forearm fracture, positioning the entire forearm in a true AP and LATERAL position may not be achieved. What positioning goal is suggested for both of these positions?

Get them to as close to a. true AP or lateral to the closest joint to fracture

Why is it so important to focus on both the wrist and the elbow when performing an AP FOREARM projection?

Getting both joints will let us evaluate for rotation

How will you visualize the following structures if the PROXIMAL HUMERUS IS DEPRESSED? Distal humerus related:

If the proximal humerus is depressed, the distal capitulum is demonstrated too far proximal to the distal medial trochlear.

For accurate positioning of a LATERAL ELBOW projection, it is important that the forearm and humerus be positioned in the same plane. How will you visualize the following structures if the PROXIMAL HUMERUS ELEVATED? Distal humerus related:

If the proximal humerus is elevated, the distal surface of the capitulum is demonstrated too far distal to the distal surface of the medial trochlea.

If the area of interest is NOT being demonstrated on a ULNAR DEVIATION projection, what slight modifications must be made so the area of interest IS being demonstrated?

Increase or decrease tube angle. Distal 25º =20% of fractures Waist 15º = 70% of fractures Proximal 5º = 10% of fractures

What additional considerations need to be made for a patient who: Are unable to lower humerus to the same plane as the forearm for radial head?

Increase tube angle because when proximal humerus is elevated we know the radial head is superimposed over the ulna.

How should the tube be adjusted for patients who are unable to fully deviate?

Increase tube angle to 20º

How does the relationship between the radius and ulna differ if the patient's humerus elevated or depressed for the LATERAL FOREARM projection? This meaning is positioned so that the humerus is not positioned in the same plane as the forearm. Depressed humerus:

Less than 1/2 superimposition of radial head of ulna

How does the relationship between the radius and ulna differ if the patient is positioned too externally or too internally for the AP FOREARM projection? Too externally:

Less than 1/8 of radial head is superimposed over ulna

What benefit is there to performing a LATERAL HAND in flexion?

May cause less stress on a fractured metacarpal -See foreign bodies -can see if fracture is posterior or anterior

McQuillen-Martensen mentions specific soft tissue widths that are associated with finger projections, what are your thoughts regarding this?

More soft tissue thickness is present on the anterior hand surface than on the posterior surface, so the side demonstrating the greatest soft tissue width on a rotated PA or a PA oblique projection is the side that the anterior surface was rotated toward. This information can be used to determine whether the finger was externally or internally rotated when a poorly positioned PA finger has been obtained.

Should the radial tuberosity be seen in profile in lateral elbow?

No

If the hand is put into a relaxed PA position, it is a true PA?

No because the palm is lifted slightly away from the IR and causes a slight lateral rotation

Will the radio-scaphoid joint be visualized open on the PA WRIST projection? Explain.

No because when the forearm is parallel with the IR the slant of the distal radius causes the posterior margin to project slightly distal to the anterior radial margin-> obscuring the radio-scaphoid joint

When positioning the patient for a LATERAL HUMERUS projection, what difficulties could you encounter with the patient positioned AP?

Not being able to rotate internally so epicondyles are perpendicular to the IR and not superimposed. Having the proximal humerus off the IR and having OID causing distortion because proximal humerus is not parallel to IR.

What is the consequence of the elbow NOT being flexed to 90 degrees for a LATERAL FOREARM projection?

Not being able to see fat pads in elbow region or be seen as a pathology(posterior fat pad)

What additional considerations need to be made for a patient who: Are unable to rotate wrist into a lateral position for radial head?

Only affects what portion of radius is visualized best. Can do either lateral or in PA wrist position.

How does McQuillen-Martensen explain the visualization of the wrist and elbow joint spaces on the AP FOREARM projection? Explain.

Open wrist joint space Closed joint space because of radial head will be in the joint space

What specific positioning tactic must be implemented for an unextendable finger?

Placing finger in AP position, and elevating metacarpals until phalange is parallel to IR and joint space is perpendicular to IR

Should the articulating surface of the radial head be visualized on an AP ELBOW projection?

Radial head articulating surface is not demonstrated.

How specifically does the tube affect the visualization of anatomical structures of the COYLE METHOD? Angled posteior to the plane of the humerus:

Radial head is going to be projected too proximal and into the capitulum

How specifically does the tube affect the visualization of anatomical structures of the COYLE METHOD? Angled anterior to the plane of the humerus:

Radial head is projected distally to coronoid process

What is the radiographic consequence if a patient is placed in an ANTERIOR OBLIQUE when imaging a LATERAL HUMERUS projection?

Results in higher brightness and lower contrast resolution in this area.

What is the relationship between the anterior surface of the radial head and the coronoid process on a LATERAL ELBOW projection? If there is a misalignment, what is the exact cause?

Should be superimposed. -Proximal humerus elevation and depression determines the anterior alignment of the radial head and coronoid process, and distal forearm depression and elevation determines the proximal alignment of the radial head and coronoid process.

Describe the anatomical orientation of the anterior & posterior margins of the distal radius?

The distal end of the radius is concave & slants aprox 11º from posterior to anterior

What is the relationship between the joints of the finger and the IR?

The finger/joint should be parallel to IR

How specifically does the tube affect the visualization of anatomical structures of the COYLE METHOD? Angled less than 45 degrees:

The medial trochlea demonstrates some capitular superimposition and the radial head superimposes over more than the tip of the coronoid process

How specifically does the tube affect the visualization of anatomical structures of the COYLE METHOD? Angled more than 45 degrees:

The medial trochlea demonstrates some capitular superimposition and the radial head superimposes over more than the tip of the coronoid process *Ulna superimposes over radius

What is the radiographic result if the patient is unable to fully extend elbow, which means there is elbow flexion, for an AP FOREARM projection?

The olecranon process will not be situated in the olecranon fossa

For accurate positioning of a LATERAL ELBOW projection, it is important that the forearm and humerus be positioned in the same plane. How will you visualize the following structures if the PROXIMAL HUMERUS ELEVATED?Proximal forearm related:

The radial head is placed too far posteriorly to the coronoid process.

How will you visualize the following structures if the PROXIMAL HUMERUS IS DEPRESSED? Proximal forearm related:

The radial head is positioned too far anteriorly to the coronoid process.

How will you visualize the following structures if the DISTAL FOREARM IS ELEVATED? Proximal forearm related:

The radial head proximally to the coronoid process

What are the 2 reasons that performing the ULNAR DEVIATION projection is so detailed? Joint related & Scaphoid related:

The radioscaphoid joint is open and the scaphoid is shown without foreshortening or excessive elongation by using proper tube angle and ulnar deviation

Explain the relationship between the 2-5 metacarpals and the anterior plane of the wrist for a LATERAL WRIST projection?

They are placed @ 10º-15º angle 2/ the anterior plane of the wrist

Where is the lesser tubercle visualized on an AP HUMERUS projection?

Vertical cortical margin of the lesser tubercle is visible about halfway between the greater tubercle and the humeral head

What is the consequence for the CR not being directed to the elbow joint? Joint related:

When the CR is centered proximal to the elbow joint, beam divergences cause the capitulum to project into the joint and when the CR is centered distal to the elbow joint, the radial head is projected into the joint space

How will you visualize the following structures if the DISTAL FOREARM IS DEPRESSED? (could be due to a thick proximal forearm)

When the distal forearm is positioned too close to the IR (depressed), the projection shows the anterior portion of the capitulum anteriorly to the medial trochlea and the radial head distally to the coronoid process.

How will you visualize the following structures if the DISTAL FOREARM IS ELEVATED? Distal humerus related:

When the distal forearm is too elevated off the IR, the projection shows the anterior portion of the capitulum posteriorly to the medial trochlea.

When has maximum ULNAR DEVIATION occurred?

When the first Metacarpal is aligned with the radius

How does McQuillen-Martensen explain the visualization of the wrist and elbow joint spaces on the LATERAL FOREARM projection?

Wrist: Divergent rays visualize a closed wrist joint due to the radius and it's 11º slant Elbow: Divergent rays visualize an open elbow joint space due to the angle of humeral epicondyles

How does a thick proximal forearm affect the visualization of the wrist and elbow joints on a LATERAL FOREARM projection?

Wrist=closed joint space Elbow: coronoid process closes joint space

When positioning the patient for a LATERAL HUMERUS projection: Should the patient be placed as close to PA as possible? Why?

Yes, because if they are not PA as possible their torso obliquity causes an increase in tissue thickness at the proximal humerus compared with the distal humerus.

What is the acceptance limit for the anterior & posterior margins of the distal radius?

doesn't superimpose no more than 1/4 of the lunate

How does the relationship between the radius and ulna differ if the patient is positioned too externally or too internally for the AP FOREARM projection? Too internally:

more than 1/8 of the radial head is superimposed over ulna. Poorly positioned epicondyles

NEW EVALUATION CRITERIA Lateral Elbow

• Anterior, posterior, and supinator fat pads are demonstrated • Elbow is flexed 90 degrees • Humerus demonstrates three concentric arcs, which are formed by the trochlear sulcus, capitulum, and medial trochlea • Distal surfaces of the capitulum and medial trochlea are nearly aligned. • Anterior surfaces of the radial head and the coronoid process are aligned -Elbow joint is open. • Anterior surfaces of the capitulum and medial trochlea are near aligned. • Proximal surfaces of the radial head and the coronoid process are aligned Radial tuberosity is not demonstrated in profile • Elbow joint is at the center of the exposure field. • Elbow joint, one fourth of the proximal forearm and distal humerus, and the lateral soft tissue are included within the exposure field.

NEW EVALUATION CRITERIA Lateral Forearm

• Brightness is uniform across the entire forearm. • Anterior aspect of the distal scaphoid and the pisiform are aligned. • Distal radius and ulna are superimposed. • Radial tuberosity is not demonstrated in profile • Ulnar styloid is demonstrated in profile posteriorly. • Anterior aspects of the radial head and coronoid process are aligned • Forearm midpoint is at the center of the exposure field. • Wrist and elbow joints and forearm soft tissue are included within the exposure field

NEW EVALUATION CRITERIA AP Forearm

• Brightness is uniform across the entire forearm. • Radial styloid is demonstrated in profile laterally. • Superimposition of the MC bases and of the radius and ulna is minimal. • Radial tuberosity is demonstrated in profile medially. • Radius and ulna run parallel. • Ulnar styloid is projected distally to the midline of the ulnar head. • One eighth (about 0.25 inch [0.6 cm]) of the radial head superimposes the ulna • Olecranon process is situated within the olecranon fossa. • Coronoid process is visible on end. • Forearm midpoint is at the center of the exposure field. • Wrist and elbow joints and forearm soft tissue are included within the exposure field

NEW EVALUATION CRITERIA Hand Oblique

• Each of the second through fifth MC midshafts demonstrate more concavity on one side than on the other. • First and second MC heads are not superimposed, the third through fifth MC heads are slightly superimposed, and only a small space is present between the fourth and fifth MC midshafts • There is no soft tissue overlap from the adjacent fingers. • Thumb is in close proximity to the hand • IP and MCP joints are demonstrated as open spaces. • Phalanges are demonstrated without foreshortening. • Thumb is in a PA oblique projection. • Third MCP joint is at the center of the exposure field. • Distal phalanges, MCs, carpals, and 1 inch (2.5 cm) of the distal radius and ulna are included within the exposure field.

NEW EVALUATION CRITERIA Lateral Humerus

• Gray shades are uniform across the humerus. • Lesser tubercle is demonstrated in profile medially. • Humeral head and greater tubercle are superimposed. • Anterior surfaces of the capitulum and medial trochlea are nearly aligned • Humeral midpoint is at the center of the exposure field. • Shoulder and elbow joints and the lateral humeral soft tissue are included within the exposure field.

NEW EVALUATION CRITERIA AP Elbow

• Medial and lateral humeral epicondyles are demonstrated in profile. • One eighth (about 0.25 inch [0.6 cm]) of the radial head superimposes the ulna • Radial tuberosity is in profile medially. • Radius and ulna are parallel. • Elbow joint space is open. • Radial head articulating surface is not demonstrated. • Olecranon process is situated within the olecranon fossa • Elbow joint is at the center of the exposure field. • Elbow joint, one fourth of the proximal forearm and distal humerus, and the lateral soft tissue are included within the exposure field.

NEW EVALUATION CRITERIA Hand Lateral

• Second through fifth MCs are superimposed • Second through fifth digits are separated, demonstrating little superimposition of the bony or soft tissue structures. • Thumb is demonstrated without superimposition of the other digits and is in a PA to slight PA oblique projection • IP joints are open. • Phalanges are not foreshortened • Thumb is positioned close to hand. • MCP joints are at the center of the exposure field. • Phalanges, MCs, carpals, and 1 inch (2.5 cm) of the distal radius and ulna are included within the exposure field.

NEW EVALUATION CRITERIA AP Humerus

• There is uniform brightness across the humerus. • Medial and lateral humeral epicondyles are demonstrated in profile. • One eighth of the radial head superimposes the ulna (about 0.25 inch • Greater tubercle is demonstrated in profile laterally. • Humeral head is demonstrated in profile medially. • Vertical cortical margin of the lesser tubercle is visible about halfway between the greater tubercle and the humeral head • Humeral midpoint is at the center of the exposure field. • Shoulder and elbow joints and the lateral humeral soft tissue are included within the exposure field.

New Evaluation Criteria Wrist Lateral

• Ulnar styloid is demonstrated in profile posteriorly • Pronator fat stripe is demonstrated • Anterior aspects of the distal scaphoid and pisiform are aligned. • Distal radius and ulna are superimposed • Distal aspects of the distal scaphoid and pisiform are aligned • Second through fifth MCs are placed at a 10- to 15-degree angle with the anterior plane of the wrist • Trapezium is demonstrated without superimposition of the first proximal MC. • First MC is demonstrated without foreshortening • Carpal bones are at the center of the exposure field • Carpal bones, one fourth of the distal ulna and radius, and half of the proximal MCs are included within the exposure field.