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Students should be able to understand different views of normal and abnormal x-rays
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Students should understand the basic theories of various Imaging methods
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Student should appreciate the abnormal findings in
Imaging

 Manual therapy techniques demands advanced understanding of joint mechanics.
 Provide a more comprehensive evaluation of our patient and ultimately better outcomes

 X-ray
 Computed Tomography
 Magnetic Resonance Imaging

X-rays are invisible to the human eye
Penetration of body by x-rays and the ionization of the atoms on the film result in the image Plain films are without contrast

Air –Black
Fat – gray black
Organs, muscles, soft tissue - shades of gray
(water based)
Bone –White
Metal – White
More radiation absorbed the lighter the Image

Radio density
(decreasing to increasing)

Arthrography: synovial joints
Myelography: spinal cord, nerve roots and dura mater
Fluoroscopy: dynamic or continuous radiograph of a physiologic function

Viewing
Imagine patient standing in front of you in anatomic position
Left or right is labeled

Minimum of 2 radiographs at right angle to each other for diagnostic purposes
 Anteroposterior (A/P)
 Lateral
 Oblique

Body section radiology
Developed in 1970 ,
Allows evaluation of series of slices Computer can make it 3D
More sensitive to each tissue type
Useful with fractures of irregularly shaped bones
Excellent for image bone, intra-articular and some
Tumors

Slice of images: 1-
10mm thick
Sagittal plane
Frontal plane
Horizontal plane

Axial Image
Air – black
Fat – black
Muscles – gray
Bone cortex – white
Bone marrow - gray

Discovered by Purcell and Bloch in 1945
Won Nobel prize in for this discovery
1953

MRI
Non-ionizing radiation Produces information via the interaction of tissue with radio frequency waves in a magnetic field Image is based on re-emission of absorbed radio frequencies in the magnetic field.

Any nucleus with an odd no of protons and neutrons will have an intrinsic spin This induces a small magnetic field around the atomic nuclei which aligns in the direction of the magnetic field Hydrogen is most abundant in the human body.
MRI: a map of hydrogen atoms in the body

MRI – creates radio wave
Produces a steady magnetic field
30,000 x stronger than EARTH’S magnetic field.

When MRI (radio wave) is turned off, the hydrogen protons will return to resting state, releasing energy
The energy (like X-ray) is a form of radio wave which detected by the radio wave receiver and sent to the computer
Computer software will generate the images

The radio waves sent to the body are short pulses of very precise strength and frequency.
By changing the strength, frequency and timing of radio wave pulses produces T1 or T2 weighted images.

T1 image (Fat-enhanced image)
Air – dark
Muscles – dark
Bone cortex – dark
Fat – very bright
Bone marrow – Bright
Good for Anatomical study

T2 MRI image (waterenhanced image)
Air – dark
Fat – intermediate dark
Muscles – dark
Bone cortex – dark
Bone marrow – intermediate dark
Good for pathological studies.

Plain film is the first diagnostic tool used.
Inverse relationship between the amount of
Radio density of an object and the blackening of the film. Air images the blackest.
MD usually orders at least 2 views as close to
90 degrees to each other to view 3D.
Routing projections ordered are AP, lateral and oblique

ABCs is a popular systemic approach to evaluating radiographs
Alignment
Bones
Cartilage
Soft Tissue

Alignment
General skeletal architecture
– General contour of bone
Alignment of bones relative to adjacent bones

General Principles
Bone Density
General bone density
– Texture abnormalities
– Local Bone density

General Principles
Cartilage Space
Joint space width
Epiphyseal plates
Subchondral bone

Soft Tissues
General Principles
Muscles
Fat pads
Joint capsule
Periosteum

Radiographic Finding of Common
Pathologies
Rheumatoid Arthritis
Soft tissue changes
Articular erosions
Joint space narrowing
Osteoporosis
Joint deformities
Changes in cervical spine

destruction
The characteristics of
RA are present in both hips: articular erosions, joint space narrowing, osteoporosis and joint deformities. The right is further advanced in destruction.

Osteoarthritis
(Degenerative Joint disease)
Osteophyte formation
Cysts or pseudo cysts
Soft tissue swelling
Joint space narrowing
Subchondral sclerosis
Joint deformities

The hallmarks of DJD are subchondral sclerosis, joint space narrowing and
Osteophyte formation. This is a lateral view of the knee

Osteoporosis
Cortical thinning
Osteopenia
Trabecular changes
Fractures

Osteoporosis in the thoracic spine can result in trabecular changes that result in compression fractures due to destruction of the bone.