Imaging of the Spine and Spinal Cord

Radiography

Overview

Before the advent of CT and MRI, X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests imaging was widely used to study the bones of the spine Spine The human spine, or vertebral column, is the most important anatomical and functional axis of the human body. It consists of 7 cervical vertebrae, 12 thoracic vertebrae, and 5 lumbar vertebrae and is limited cranially by the skull and caudally by the sacrum. Vertebral Column: Anatomy.

Views and spine Spine The human spine, or vertebral column, is the most important anatomical and functional axis of the human body. It consists of 7 cervical vertebrae, 12 thoracic vertebrae, and 5 lumbar vertebrae and is limited cranially by the skull and caudally by the sacrum. Vertebral Column: Anatomy structures:

• Frontal Frontal The bone that forms the frontal aspect of the skull. Its flat part forms the forehead, articulating inferiorly with the nasal bone and the cheek bone on each side of the face. Skull: Anatomy view (anteroposterior (AP) or posteroanterior (PA)):
  • Spinous processes: hyperdense structures over the midline
  • Pedicles: round, lucent circles on both sides of the spinous processes
  • Facet joints 
  • Vertebral body Vertebral body Main portion of the vertebra which bears majority of the weight. Vertebral Column: Anatomy heights and intervertebral disk spaces
• Posterior oblique view:
  • Parts of the spine Spine The human spine, or vertebral column, is the most important anatomical and functional axis of the human body. It consists of 7 cervical vertebrae, 12 thoracic vertebrae, and 5 lumbar vertebrae and is limited cranially by the skull and caudally by the sacrum. Vertebral Column: Anatomy are represented as parts of a dog.
  • “Scottie dog” sign
• Open-mouth (odontoid) view: alignment of C1 lateral masses and C2 vertebra
• Lateral view:
  • Evaluation of spinal alignment
  • Vertebral body Vertebral body Main portion of the vertebra which bears majority of the weight. Vertebral Column: Anatomy heights and intervertebral disk spaces

Normal radiographic findings

• Bones:
  • Appear white (radiodense)
  • Certain pathologies can differ in radiodensity.
• Normal spine Spine The human spine, or vertebral column, is the most important anatomical and functional axis of the human body. It consists of 7 cervical vertebrae, 12 thoracic vertebrae, and 5 lumbar vertebrae and is limited cranially by the skull and caudally by the sacrum. Vertebral Column: Anatomy:
  • Cervical and lumbar lordosis (anterior convexity) 
  • Thoracic kyphosis Kyphosis Deformities of the spine characterized by an exaggerated convexity of the vertebral column. The forward bending of the thoracic region usually is more than 40 degrees. This deformity sometimes is called round back or hunchback. Osteoporosis (posterior convexity)
• Spinal alignment:
  • The spinous processes, pedicles, and laminae of the vertebrae must be checked for adequate positioning.
  • Vertebral lines should be parallel:
    • Anterior vertebral line: connects the anterior margins of the vertebral bodies
    • Posterior vertebral line: connects the posterior margins of the vertebral bodies
    • Spinolaminar line: connects the posterior margins of the spinal canal Spinal Canal The cavity within the spinal column through which the spinal cord passes. Spinal Cord Injuries
    • Interspinous line: connects the tips of the spinous processes
• Soft tissues: cannot be clearly seen ( radiolucent Radiolucent An object of low density that is permeable to X-rays (looks black) X-rays) unless they an contain abnormal density (such as calcification)

CT

Overview

A CT scan can evaluate both bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types and soft tissue Soft Tissue Soft Tissue Abscess structures.

• Indications for spinal CT scan:
  • Trauma setting in cases such as: 
    • Glasgow Coma Coma Coma is defined as a deep state of unarousable unresponsiveness, characterized by a score of 3 points on the GCS. A comatose state can be caused by a multitude of conditions, making the precise epidemiology and prognosis of coma difficult to determine. Coma Scale Scale Dermatologic Examination score < 15
    • Unstable vital signs
    • Acute paralysis
  • For evaluation before or after surgery, especially if there is a contraindication to MRI
  • Malignancy Malignancy Hemothorax 
  • To guide some procedures (e.g., CT-guided epidural injection)
• Contraindications Contraindications A condition or factor associated with a recipient that makes the use of a drug, procedure, or physical agent improper or inadvisable. Contraindications may be absolute (life threatening) or relative (higher risk of complications in which benefits may outweigh risks). Noninvasive Ventilation: pregnancy Pregnancy The status during which female mammals carry their developing young (embryos or fetuses) in utero before birth, beginning from fertilization to birth. Pregnancy: Diagnosis, Physiology, and Care

Normal CT findings

Anatomy:

• Bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types appears hyperdense (> 250–700 Hounsfield units Hounsfield Units Computed Tomography (CT)) 
• Most vertebrae have common structures: 
  • Body 
  • Pedicles 
  • Transverse processes
  • Spinous process
  • Spinal canal Spinal Canal The cavity within the spinal column through which the spinal cord passes. Spinal Cord Injuries (where the spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord: Anatomy lies) 
• Vertebrae also differ in shape and structures according to their anatomic position.
• Spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord: Anatomy density on CT (in Hounsfield units Hounsfield Units Computed Tomography (CT)): 
  • Gray matter Gray matter Region of central nervous system that appears darker in color than the other type, white matter. It is composed of neuronal cell bodies; neuropil; glial cells and capillaries but few myelinated nerve fibers. Cerebral Cortex: Anatomy > white matter White Matter The region of central nervous system that appears lighter in color than the other type, gray matter. It mainly consists of myelinated nerve fibers and contains few neuronal cell bodies or dendrites. Brown-Séquard Syndrome > CSF 
  • Note: Evaluation of gray versus white matter White Matter The region of central nervous system that appears lighter in color than the other type, gray matter. It mainly consists of myelinated nerve fibers and contains few neuronal cell bodies or dendrites. Brown-Séquard Syndrome is more difficult in the spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord: Anatomy than in the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification.

Different planes can be used: 

• Axial Axial Computed Tomography (CT)
• Sagittal Sagittal Computed Tomography (CT) 
• Coronal Coronal Computed Tomography (CT)

MRI

Overview

MRI provides superior visualization of intraspinal anatomy.

• Indications for spinal MRI:
  • Spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord: Anatomy injury:
    • Hemorrhage
    • Spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord: Anatomy contusion
    • Edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema
    • Compression Compression Blunt Chest Trauma by a bony fragment
    • Acute traumatic disk herniation Herniation Omphalocele
    • Ligamentous injury
  • Low back pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways: 
    • Disk herniation Herniation Omphalocele 
    • Malignancy Malignancy Hemothorax 
    • Infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease (e.g., osteomyelitis Osteomyelitis Osteomyelitis is an infection of the bone that results from the spread of microorganisms from the blood (hematogenous), nearby infected tissue, or open wounds (non-hematogenous). Infections are most commonly caused by Staphylococcus aureus. Osteomyelitis or abscess Abscess Accumulation of purulent material in tissues, organs, or circumscribed spaces, usually associated with signs of infection. Chronic Granulomatous Disease) 
  • Neural tube Neural tube A tube of ectodermal tissue in an embryo that will give rise to the central nervous system, including the spinal cord and the brain. Lumen within the neural tube is called neural canal which gives rise to the central canal of the spinal cord and the ventricles of the brain. Gastrulation and Neurulation defects 
  • Spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord: Anatomy disease (e.g., multiple sclerosis Sclerosis A pathological process consisting of hardening or fibrosis of an anatomical structure, often a vessel or a nerve. Wilms Tumor)
• Relative and absolute contraindications Contraindications A condition or factor associated with a recipient that makes the use of a drug, procedure, or physical agent improper or inadvisable. Contraindications may be absolute (life threatening) or relative (higher risk of complications in which benefits may outweigh risks). Noninvasive Ventilation: 
  • Ferromagnetic implants Ferromagnetic Implants Magnetic Resonance Imaging (MRI): can move or overheat, causing injury
  • Electrical or mechanical devices:
    • Cochlear implants
    • Pacemakers
    • Drug/ insulin Insulin Insulin is a peptide hormone that is produced by the beta cells of the pancreas. Insulin plays a role in metabolic functions such as glucose uptake, glycolysis, glycogenesis, lipogenesis, and protein synthesis. Exogenous insulin may be needed for individuals with diabetes mellitus, in whom there is a deficiency in endogenous insulin or increased insulin resistance. Insulin infusion pumps
  • Claustrophobia Claustrophobia Magnetic Resonance Imaging (MRI): treated with sedatives
  • Allergy Allergy An abnormal adaptive immune response that may or may not involve antigen-specific IgE Type I Hypersensitivity Reaction to contrast agent: may manifest as anaphylaxis Anaphylaxis An acute hypersensitivity reaction due to exposure to a previously encountered antigen. The reaction may include rapidly progressing urticaria, respiratory distress, vascular collapse, systemic shock, and death. Type I Hypersensitivity Reaction
  • Abnormal renal function: if contrast agent is needed

Normal MRI findings

Anatomy:

• Most vertebrae have common structures: 
  • Body 
  • Pedicles 
  • Transverse processes
  • Spinous process
  • Spinal canal Spinal Canal The cavity within the spinal column through which the spinal cord passes. Spinal Cord Injuries
• Shape and structures of vertebrae differ according to their anatomic position.
• Intervertebral disk: The nucleus Nucleus Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (cell nucleolus). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the endoplasmic reticulum. A cell may contain more than one nucleus. The Cell: Organelles pulposus should be contained within the annulus fibrosus Annulus Fibrosus Spinal Disk Herniation.

On T2-weighted images T2-Weighted Images Imaging of the Head and Brain:

• Nucleus Nucleus Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (cell nucleolus). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the endoplasmic reticulum. A cell may contain more than one nucleus. The Cell: Organelles pulposus: hyperintense Hyperintense Magnetic Resonance Imaging (MRI) (high water content, which is T2 hyperintense Hyperintense Magnetic Resonance Imaging (MRI))
• Annulus fibrosus Annulus Fibrosus Spinal Disk Herniation: hypointense Hypointense Magnetic Resonance Imaging (MRI) (due to the high collagen Collagen A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of skin; connective tissue; and the organic substance of bones (bone and bones) and teeth (tooth). Connective Tissue: Histology content)

Different planes can be used:

• Axial Axial Computed Tomography (CT)
• Sagittal Sagittal Computed Tomography (CT) 
• Coronal Coronal Computed Tomography (CT)

Tissue appearance on MRI

Clinical Correlation

Compression Compression Blunt Chest Trauma fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures

• Vertebral compression Compression Blunt Chest Trauma fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures: most common type of osteoporotic fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures
• Most common sites:
  • T7–T8
  • T12–L1
• Kummell disease: delayed vertebral body Vertebral body Main portion of the vertebra which bears majority of the weight. Vertebral Column: Anatomy collapse, which is a rare complication of osteoporotic compression Compression Blunt Chest Trauma fractures and suggests avascular Avascular Corneal Abrasions, Erosion, and Ulcers necrosis Necrosis The death of cells in an organ or tissue due to disease, injury or failure of the blood supply. Ischemic Cell Damage
• X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests:
  • Wedge-shaped vertebral body Vertebral body Main portion of the vertebra which bears majority of the weight. Vertebral Column: Anatomy: compression Compression Blunt Chest Trauma of the superior and/or anterior surface
  • +/– Kyphosis Kyphosis Deformities of the spine characterized by an exaggerated convexity of the vertebral column. The forward bending of the thoracic region usually is more than 40 degrees. This deformity sometimes is called round back or hunchback. Osteoporosis
  • Kummell disease is seen with air in the vertebral body Vertebral body Main portion of the vertebra which bears majority of the weight. Vertebral Column: Anatomy representing avascular Avascular Corneal Abrasions, Erosion, and Ulcers necrosis Necrosis The death of cells in an organ or tissue due to disease, injury or failure of the blood supply. Ischemic Cell Damage.
• MRI or CT considered if further evaluation (acuity or instability of wedge fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures) is needed.

Burst fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures

• Vertebral compression Compression Blunt Chest Trauma injuries affect Affect The feeling-tone accompaniment of an idea or mental representation. It is the most direct psychic derivative of instinct and the psychic representative of the various bodily changes by means of which instincts manifest themselves. Psychiatric Assessment the cervical, thoracic, and lumbar areas, with high-energy axial Axial Computed Tomography (CT) loading:
  • From above, via the skull Skull The skull (cranium) is the skeletal structure of the head supporting the face and forming a protective cavity for the brain. The skull consists of 22 bones divided into the viscerocranium (facial skeleton) and the neurocranium. Skull: Anatomy
  • From below, via the pelvis Pelvis The pelvis consists of the bony pelvic girdle, the muscular and ligamentous pelvic floor, and the pelvic cavity, which contains viscera, vessels, and multiple nerves and muscles. The pelvic girdle, composed of 2 “hip” bones and the sacrum, is a ring-like bony structure of the axial skeleton that links the vertebral column with the lower extremities. Pelvis: Anatomy or feet
• Body of the vertebra breaks up or bursts in an AP plane.
• X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests: 3-column unstable fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures of the vertebral body Vertebral body Main portion of the vertebra which bears majority of the weight. Vertebral Column: Anatomy 
• CT:
  • 3-column unstable fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures of the vertebral body Vertebral body Main portion of the vertebra which bears majority of the weight. Vertebral Column: Anatomy 
  • Vertebral body Vertebral body Main portion of the vertebra which bears majority of the weight. Vertebral Column: Anatomy retropulsion 

Jefferson fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures

• Bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures of C1 ( atlas Atlas The first cervical vertebra. Vertebral Column: Anatomy)
• X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests:
  • Seen on open-mouth X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests
  • Lateral displacement Displacement The process by which an emotional or behavioral response that is appropriate for one situation appears in another situation for which it is inappropriate. Defense Mechanisms of the lateral masses of C1 away from the dens (> 6 mm MM Multiple myeloma (MM) is a malignant condition of plasma cells (activated B lymphocytes) primarily seen in the elderly. Monoclonal proliferation of plasma cells results in cytokine-driven osteoclastic activity and excessive secretion of IgG antibodies. Multiple Myeloma indicates ligament injury) 
• CT: seen as C1 fractures involving the anterior and the posterior arches of C1

Hangman’s fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures

• Traumatic spondylolisthesis Spondylolisthesis Displacement of a vertebra forward in relation to the vertebra below Back Pain of C2 ( axis Axis The second cervical vertebra. Vertebral Column: Anatomy) 
• X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests: 
  • Bilateral fractures of the lamina and pedicles of C2
  • Anterior displacement Displacement The process by which an emotional or behavioral response that is appropriate for one situation appears in another situation for which it is inappropriate. Defense Mechanisms of the C2 vertebral body Vertebral body Main portion of the vertebra which bears majority of the weight. Vertebral Column: Anatomy (anterolisthesis of C2 on C3)

Chance fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures

• “Seatbelt fractures”
• Flexion-distraction injury of the spine Spine The human spine, or vertebral column, is the most important anatomical and functional axis of the human body. It consists of 7 cervical vertebrae, 12 thoracic vertebrae, and 5 lumbar vertebrae and is limited cranially by the skull and caudally by the sacrum. Vertebral Column: Anatomy, often in the thoracolumbar area
• Seen in both X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests and CT (more accurate details):
  • Involvement of the: 
    • Vertebral body Vertebral body Main portion of the vertebra which bears majority of the weight. Vertebral Column: Anatomy
    • Pedicles 
    • Spinous process
  • ↑ Interspinous distance 
• MRI used for associated ligament and/or cord injury assessment.

Spondylosis Spondylosis A degenerative spinal disease that can involve any part of the vertebra, the intervertebral disk, and the surrounding soft tissue. Central Cord Syndrome, spondylolysis and spondylolisthesis Spondylolisthesis Displacement of a vertebra forward in relation to the vertebra below Back Pain

• Imaging is performed to evaluate back pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways and is commonly limited early, unless the patient exhibits red flags such as fever Fever Fever is defined as a measured body temperature of at least 38°C (100.4°F). Fever is caused by circulating endogenous and/or exogenous pyrogens that increase levels of prostaglandin E2 in the hypothalamus. Fever is commonly associated with chills, rigors, sweating, and flushing of the skin. Fever, trauma history, or neurologic findings.
• Spondylosis Spondylosis A degenerative spinal disease that can involve any part of the vertebra, the intervertebral disk, and the surrounding soft tissue. Central Cord Syndrome: 
  • Degeneration/ osteoarthritis Osteoarthritis Osteoarthritis (OA) is the most common form of arthritis, and is due to cartilage destruction and changes of the subchondral bone. The risk of developing this disorder increases with age, obesity, and repetitive joint use or trauma. Patients develop gradual joint pain, stiffness lasting < 30 minutes, and decreased range of motion. Osteoarthritis of the vertebral column Vertebral column The human spine, or vertebral column, is the most important anatomical and functional axis of the human body. It consists of 7 cervical vertebrae, 12 thoracic vertebrae, and 5 lumbar vertebrae and is limited cranially by the skull and caudally by the sacrum. Vertebral Column: Anatomy
  • X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests:
    • Loss of height of the disk space 
    • Sclerosis Sclerosis A pathological process consisting of hardening or fibrosis of an anatomical structure, often a vessel or a nerve. Wilms Tumor of the end plates 
    • Vacuum phenomenon: gas within the disk space
    • Facet degenerative changes Degenerative Changes Spinal Stenosis: bony osteophytes
• Spondylolysis:
  • Defect (stress fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures or separation) in the pars interarticularis (a bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types connecting one facet joint to another)
  • Children and adolescents most susceptible
  • Majority in L5
  • X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests: break seen in pars interarticularis
  • MRI:
    • Detects bone marrow Bone marrow The soft tissue filling the cavities of bones. Bone marrow exists in two types, yellow and red. Yellow marrow is found in the large cavities of large bones and consists mostly of fat cells and a few primitive blood cells. Red marrow is a hematopoietic tissue and is the site of production of erythrocytes and granular leukocytes. Bone marrow is made up of a framework of connective tissue containing branching fibers with the frame being filled with marrow cells. Bone Marrow: Composition and Hematopoiesis edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema in the pedicle and pars region (early sign of injury)
    • Important to detect early bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types stress reaction to prevent defects.
  • SPECT SPECT An imaging technique using a device which combines tomography, emission-computed, single-photon and tomography, x-ray computed in the same session. Nuclear Imaging can be used, but it has a risk of radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma exposure Exposure ABCDE Assessment.
• Spondylolisthesis Spondylolisthesis Displacement of a vertebra forward in relation to the vertebra below Back Pain: 
  • Slippage of a vertebra forward in relation to the vertebra below it
  • Often accompanies spondylolysis (especially in bilateral defects)
  • Common in lumbar area
  • X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests (lateral radiograph):
    • Anterior displacement Displacement The process by which an emotional or behavioral response that is appropriate for one situation appears in another situation for which it is inappropriate. Defense Mechanisms of a vertebra relative to that below it
    • Disruption of vertebral lines

Disk herniation Herniation Omphalocele

• Herniation Herniation Omphalocele of the nucleus Nucleus Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (cell nucleolus). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the endoplasmic reticulum. A cell may contain more than one nucleus. The Cell: Organelles pulposus (beyond the annulus fibrosus Annulus Fibrosus Spinal Disk Herniation) into the spinal canal Spinal Canal The cavity within the spinal column through which the spinal cord passes. Spinal Cord Injuries through a defect:
  • Protrusion: base wider than herniation Herniation Omphalocele dome 
  • Extrusion: base narrower than herniation Herniation Omphalocele dome
• X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests: limited benefit
• MRI: 
  • Both CT and MRI are sensitive, but MRI can identify other pathologies in the spine Spine The human spine, or vertebral column, is the most important anatomical and functional axis of the human body. It consists of 7 cervical vertebrae, 12 thoracic vertebrae, and 5 lumbar vertebrae and is limited cranially by the skull and caudally by the sacrum. Vertebral Column: Anatomy (inflammatory, vascular disorders).
  • No ionizing radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma

Sacroiliitis Sacroiliitis Inflammation of the sacroiliac joint. It is characterized by lower back pain, especially upon walking, fever, uveitis; psoriasis; and decreased range of motion. Many factors are associated with and cause sacroiliitis including infection; injury to spine, lower back, and pelvis; degenerative arthritis; and pregnancy. Ankylosing Spondylitis

• Inflammation Inflammation Inflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body’s defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation of the sacroiliac joint Sacroiliac Joint The immovable joint formed by the lateral surfaces of the sacrum and ilium. Pelvis: Anatomy(s)
• X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests:
  • 1st-line test
  • Sclerosis Sclerosis A pathological process consisting of hardening or fibrosis of an anatomical structure, often a vessel or a nerve. Wilms Tumor of the iliac side of the sacroiliac joint Sacroiliac Joint The immovable joint formed by the lateral surfaces of the sacrum and ilium. Pelvis: Anatomy
  • Irregular joint end plate
• CT:
  • Detects erosions Erosions Corneal Abrasions, Erosion, and Ulcers, bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types sclerosis Sclerosis A pathological process consisting of hardening or fibrosis of an anatomical structure, often a vessel or a nerve. Wilms Tumor, ankylosis
  • Significant radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma 
• MRI:
  • Most sensitive test
  • Early changes are detected when other imaging studies are negative.
  • Can show bone marrow Bone marrow The soft tissue filling the cavities of bones. Bone marrow exists in two types, yellow and red. Yellow marrow is found in the large cavities of large bones and consists mostly of fat cells and a few primitive blood cells. Red marrow is a hematopoietic tissue and is the site of production of erythrocytes and granular leukocytes. Bone marrow is made up of a framework of connective tissue containing branching fibers with the frame being filled with marrow cells. Bone Marrow: Composition and Hematopoiesis edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema and disease severity

Vertebral metastatic lesions

• Metastatic involvement of the vertebral spine Spine The human spine, or vertebral column, is the most important anatomical and functional axis of the human body. It consists of 7 cervical vertebrae, 12 thoracic vertebrae, and 5 lumbar vertebrae and is limited cranially by the skull and caudally by the sacrum. Vertebral Column: Anatomy
• Bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types: 3rd most frequent site of metastasis Metastasis The transfer of a neoplasm from one organ or part of the body to another remote from the primary site. Grading, Staging, and Metastasis
  • Predominantly osteoblastic (↑ irregular bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types trabeculae): prostate Prostate The prostate is a gland in the male reproductive system. The gland surrounds the bladder neck and a portion of the urethra. The prostate is an exocrine gland that produces a weakly acidic secretion, which accounts for roughly 20% of the seminal fluid. , small-cell cancer, carcinoid
  • Predominantly osteolytic (↑ bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types destruction): non-small-cell cancer, renal cell carcinoma Renal cell carcinoma Renal cell carcinoma (RCC) is a tumor that arises from the lining of the renal tubular system within the renal cortex. Renal cell carcinoma is responsible for 80%-85% of all primary renal neoplasms. Most RCCs arise sporadically, but smoking, hypertension, and obesity are linked to its development. Renal Cell Carcinoma, thyroid cancer Thyroid cancer Thyroid cancer is a malignancy arising from the thyroid gland cells: thyroid follicular cells (papillary, follicular, and anaplastic carcinomas) and calcitonin-producing C cells (medullary carcinomas). Rare cancers are derived from the lymphocytes (lymphoma) and/or stromal and vascular elements (sarcoma). Thyroid Cancer
  • Mixed: breast cancer Breast cancer Breast cancer is a disease characterized by malignant transformation of the epithelial cells of the breast. Breast cancer is the most common form of cancer and 2nd most common cause of cancer-related death among women. Breast Cancer
• X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests:
  • Initial test
  • Osteolytic lesions: radiolucent Radiolucent An object of low density that is permeable to X-rays (looks black) X-rays lesions (“lytic” = “lucent”)
  • Osteoblastic lesions: radiopaque Radiopaque An object of high density that blocks X-rays (looks white) X-rays lesions 
• CT and MRI: help determine complications such as spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord: Anatomy compression Compression Blunt Chest Trauma, impending pathologic fractures

Tumors

MRI is the study of choice for spinal tumors.

• Meningioma Meningioma Meningiomas are slow-growing tumors that arise from the meninges of the brain and spinal cord. The vast majority are benign. These tumors commonly occur in individuals with a history of high doses of skull radiation, head trauma, and neurofibromatosis 2. Meningioma:
  • An intradural, extramedullary spinal tumor Tumor Inflammation that arises from the meninges Meninges The brain and the spinal cord are enveloped by 3 overlapping layers of connective tissue called the meninges. The layers are, from the most external layer to the most internal layer, the dura mater, arachnoid mater, and pia mater. Between these layers are 3 potential spaces called the epidural, subdural, and subarachnoid spaces. Meninges: Anatomy.
  • Usually isointense to gray matter Gray matter Region of central nervous system that appears darker in color than the other type, white matter. It is composed of neuronal cell bodies; neuropil; glial cells and capillaries but few myelinated nerve fibers. Cerebral Cortex: Anatomy on T1 and T2
  • Intense and homogeneous enhancement Homogeneous Enhancement Imaging of the Spleen 
  • Compresses the cord
• Ependymoma Ependymoma Ependymomas are glial cell tumors arising from CSF-producing ependymal cells lining the ventricular system. Ependymomas most commonly occur within the posterior fossa in contact with the 4th ventricle, or within the intramedullary spinal cord. Ependymoma: 
  • Centrally located mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast within the cord (intramedullary)
  • Isointense to hypointense Hypointense Magnetic Resonance Imaging (MRI) lesion on T1
  • Hyperintense Hyperintense Magnetic Resonance Imaging (MRI) lesion on T2
  • Intense and inhomogeneous enhancement

Vertebral osteomyelitis Osteomyelitis Osteomyelitis is an infection of the bone that results from the spread of microorganisms from the blood (hematogenous), nearby infected tissue, or open wounds (non-hematogenous). Infections are most commonly caused by Staphylococcus aureus. Osteomyelitis and diskitis

• Infection of the bones of the spine Spine The human spine, or vertebral column, is the most important anatomical and functional axis of the human body. It consists of 7 cervical vertebrae, 12 thoracic vertebrae, and 5 lumbar vertebrae and is limited cranially by the skull and caudally by the sacrum. Vertebral Column: Anatomy from direct inoculation (trauma), hematogenous Hematogenous Hepatocellular Carcinoma (HCC) and Liver Metastases or contiguous spread
• X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests:
  • Used as adjunct to MRI
  • Changes noted when disease is advanced
• MRI:
  • Most sensitive test
  • T1-weighted images T1-Weighted Images Imaging of the Head and Brain: decreased signal intensity in the disk and vertebral bodies, with less well defined end plate 
  • T2-weighted images T2-Weighted Images Imaging of the Head and Brain: increased disk signal intensity (can have increased vertebral body Vertebral body Main portion of the vertebra which bears majority of the weight. Vertebral Column: Anatomy signal intensity)
  • After contrast administration: 
    • Vertebral body Vertebral body Main portion of the vertebra which bears majority of the weight. Vertebral Column: Anatomy and disk enhancement
    • +/– ring enhancement Ring Enhancement Brain Abscess indicating abscess Abscess Accumulation of purulent material in tissues, organs, or circumscribed spaces, usually associated with signs of infection. Chronic Granulomatous Disease formation
• CT done when MRI is not available or is contraindicated.

Epidural abscess Epidural abscess Circumscribed collections of suppurative material occurring in the spinal or intracranial epidural space. The majority of epidural abscesses occur in the spinal canal and are associated with osteomyelitis of a vertebral body; analgesia, epidural; and other conditions. Clinical manifestations include local and radicular pain, weakness, sensory loss, urinary incontinence, and fecal incontinence. Cranial epidural abscesses are usually associated with osteomyelitis of a cranial bone, sinusitis, or otitis media. Retropharyngeal Abscess

• Accumulation of pus between the outer meningeal layer and the vertebral column Vertebral column The human spine, or vertebral column, is the most important anatomical and functional axis of the human body. It consists of 7 cervical vertebrae, 12 thoracic vertebrae, and 5 lumbar vertebrae and is limited cranially by the skull and caudally by the sacrum. Vertebral Column: Anatomy
• MRI:
  • With contrast: preferred method
  • Detects early changes and details regarding location and extent
  • T2-weighted images T2-Weighted Images Imaging of the Head and Brain:
    • Hyperintense Hyperintense Magnetic Resonance Imaging (MRI) mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast with rim enhancement and a hypointense Hypointense Magnetic Resonance Imaging (MRI) center
    • If diffusion Diffusion The tendency of a gas or solute to pass from a point of higher pressure or concentration to a point of lower pressure or concentration and to distribute itself throughout the available space. Diffusion, especially facilitated diffusion, is a major mechanism of biological transport. Peritoneal Dialysis and Hemodialysis restriction series are obtained, abscesses tend to show increased signal.

Spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord: Anatomy transection

• Traumatic spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord: Anatomy injury: most occur with injury to the vertebral column Vertebral column The human spine, or vertebral column, is the most important anatomical and functional axis of the human body. It consists of 7 cervical vertebrae, 12 thoracic vertebrae, and 5 lumbar vertebrae and is limited cranially by the skull and caudally by the sacrum. Vertebral Column: Anatomy ( bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures, joint dislocation, ligament tear, or intervertebral disk herniation Herniation Omphalocele)
• MRI:
  • Loss of cord continuity
  • +/– compression Compression Blunt Chest Trauma by bony fragments 

Multiple sclerosis Sclerosis A pathological process consisting of hardening or fibrosis of an anatomical structure, often a vessel or a nerve. Wilms Tumor

• CNS disease characterized by immune-mediated inflammatory demyelination Demyelination Multiple Sclerosis
• MRI:
  • Test of choice
  • Demyelination Demyelination Multiple Sclerosis would be seen:
    • T1: Lesions are isointense or hypointense Hypointense Magnetic Resonance Imaging (MRI).
    • T2: Lesions are hyperintense Hyperintense Magnetic Resonance Imaging (MRI).
    • T1 + contrast: Active areas of demyelination Demyelination Multiple Sclerosis show contrast enhancement (incomplete ring enhancement Ring Enhancement Brain Abscess can be seen).