This document discusses the benefits of physical therapists understanding medical imaging of bones and joints. It explains that understanding imaging allows physical therapists to correctly interpret radiologist reports, communicate effectively with doctors, and enhance their awareness of a patient's condition. Understanding imaging can help physical therapists in screening for medical conditions, determining differential diagnoses, and monitoring the effectiveness of conservative treatments like physical therapy. The document also provides an overview of various imaging techniques like x-rays and discusses how physical therapists can benefit from privileges like referring patients for imaging tests.
2. WHY PT’S NEED
TO KNOW ABOUT
MEDICAL
IMAGING
• To correctly interpret radiologists
written report
• To speak the same language as
physicians
• To enhance awareness of the
patient's condition
• Radiologist reports are often
written for the clinicians and may
not consider information the PT
needs to treat the patient and to
adequately formulate a prognosis
3. WHAT IS
THE
BENEFIT?
• For healthcare providers involved
in the management of patients
with musculoskeletal disorders, the
ability to order diagnostic imaging
is a beneficial adjunct to screening
for medical referral and differential
diagnosis.
• A trial of conservative treatment,
such as physical therapy, is often
recommended prior to the use of
interventions.
4. WHAT IS
THE
BENEFIT?
• Physical therapists are becoming
more autonomous and can practice
some degree of direct access in
medical fields.
• Referral for imaging privileges
could increase the effectiveness
and efficiency of healthcare
delivery, particularly in
combination with direct access
management.
5. WHAT IS
THE
BENEFIT?
• Physical therapists in the military
system have been recognized as
providers of choice for nonsurgical
musculoskeletal conditions and are
considered an invaluable asset to
the military healthcare team.
• Their privileges have expanded
beyond the typical scope of
physical therapy practice to
efficiently perform musculoskeletal
evaluations in a direct-access,
physician-extender role.
6. WHAT IS
THE
BENEFIT?
• Their role including
(1) referring patients for
appropriate diagnostic imaging
tests,
(2) prescribing certain analgesic,
nonsteroidal anti-inflammatory,
and muscle relaxant
medications,
(3) restricting patients to their living
quarters for up to 72 hours,
8. IMPORTANT FACTS ABOUT X-RAYS
• Plain film radiography remains as the 1st
order diagnostic imaging modality
• X-rays are a form of electromagnetic
radiation like visible light but of shorter
wavelength
• X-ray tube generates x-rays and beams
them toward the patient. Some of the
energy is absorbed; rest passes through
patient and hits the film plate.
• Shades of gray on film are a representation
of the different densities of the anatomic
tissues through which the x rays have
passed.
9. • Tissues with greater density will absorb more of the x-
ray so less of the beam reaches the film plate. The
resultant image is therefore lighter.
• Tissues with less density will allow more x-ray to reach
the film so it will be darker. This is called
radiodensity and is determined by:
*composition of the structure
*thickness of the structure
10. BODY COMPOSITION
AIR: Black
Examples- trachea, lungs, stomach,
digestive tract
FAT: Gray black
Examples- subcutaneously along
muscle sheaths; around
viscera
11. BODY COMPOSITION
WATER: Gray
Examples: Muscles, nerves, tendons,
ligaments, vessels
(All of these structures have the same density and
therefore are hard to distinguish on plain x-rays.)
20. VIEWING RADIOGRAPHS
• In AP and Lateral views, the film is always positioned
on the view box with the patient positioned as if facing
the viewer in anatomical position.
• Hands and feet are placed with fingers or toes pointing
up
• Lateral views are placed on the box in the direction
that the beam traveled.
• Magnetic markers are used for R and L. Use this as the
reference to place the patient facing the viewer in
anatomical position.
21.
22. FACTORS INFLUENCING QUALITY
OF XRAYS
• Detail: Geometric sharpness. Can be
affected by movement
• Distortion: Difference between the
actual imagery and the recorded image.
Geometric distortion occurs as the beam
progresses away from the perpendicular.
• Contrast: Difference between adjacent
images. It is controlled by adjusting the
energy of the beam.
23. ANATOMY OF BONE
Compact Bone: forms outer shell or cortex
of bone; dense
Cancellous Bone: forms the inner aspect
of
bone except for the
marrow
cavity; spongy
24. Periosteum: Covers the cortex; fibrous layer which
contains blood vessels, nerves and lymphatics.
Endosteum: Membrane lining the inner aspect of the
cortex and medullary (marrow) cavity
Diaphysis: Shaft
Metaphysis: Flared part at either end of shaft
Epiphysis: Either end of the bone
ANATOMY OF BONE
25. PROCESSES OF BONE GROWTH
• Ossification: Process of replacing
cartilaginous model with bone
• Endochondral Ossification: How
bones grow in length
• Intramembranous Ossification: How
bones grow in width
• Physis: The growth plate evidenced by
the “open space”
26.
27.
28.
29.
30. ABC’S OF
VIEWING
FILMS
A: ALIGNMENT
1. Assess the size of the bones: gigantism,
dwarfism, etc
2. Assess the number of bones
3. Assess each bone for normal shape and
contour; irregularities can be from
trauma, congenital, developmental or
pathological
4. Assess joint position: trauma,
inflammatory
or degenerative disease
31.
32.
33. ABC’S OF
VIEWING
FILMS
B. BONE DENSITY
1. Assess general bone density
*contrast between soft tissues and bone
*contrast between cortical margin and
the
cancellous bone and medullary cavity
*loss of contrast means loss of bone
density
ie: osteoporosis
*labeled as osteopenia, demineralization
34. • Originally coined for the changes
of senile osteoporosis, biconcave
deformities of the vertebral bodies
("fish vertebrae") are characteristic of
disorders in which there is diffuse
weakening of the bone. The name is
derived from the actual appearance
of a fish vertebrae which normally
has depressions in the superior and
inferior surfaces of each vertebral
body. This sign is typically used for
osteopenia.
35.
36. ABC’S OF
VIEWING
FILMS
Assess local bone density:
Looking for sclerosis; sign of repair in the
bone. Excessive sclerosis is indicative of
Bone Lesions:
Osteolytic- bone destroying so appear
radiolucent as in RA or Gout
Osteoblastic- bone forming;
osteoid osteomas
Texture abnormalities: looking at
appearance
45. ABC’S OF
VIEWING
FILMS
S: SOFT TISSUES
1. Assess the gross size of the
musculature
2. Assess outline of joint capsules:
normally
indistinct; become obvious during
episodes
of increased joint volume from
infection,
hemorrhage or inflammation
3. Assess the periosteum: normally
indistinct