Spine part 1 and part 2 Flashcards

Question

NICE guidance on C-spine injury

Answer 1

Within NICE’s Quality Standards [QS74] for Head Injury, it states; People attending an emergency department with a head injury have a CT cervical spine scan within 1 hour of a risk factor for spinal injury being identified. Rationale: Head injuries can be fatal or cause disability if there is damage to the cervical spine that is not identified and treated quickly. A CT cervical spine scan within 1 hour will allow rapid treatment and improve outcomes for people with head injuries that have damaged the cervical spine

Answer 2

a burning or prickling sensation, caused by pressure on or damage to nerves; ‘pins and needles’.

Answer 3

If a neurological abnormality attributable to a spinal cord injury is still considered after CT, then perform MRI. Children (under 16s) MRI should be performed if there is a strong suspicion of: Cervical spinal cord injury as indicated by the Canadian C-spine rules and by clinical assessment; or cervical spinal column injury as indicated by clinical assessment or abnormal neurological signs or symptoms, or both Consider plain film x-rays in children who do not fulfil the criteria for MRI but clinical suspicion remains Discuss findings with Consultant Radiologist and perform further imaging, if needed

Answer 4

Alignment checks and measurements to consider when assessing the C-spine for fractures: Vertebral Contour Lines Pre-Dental Space Soft Tissue Spinous Processes (C1-C3 Peg View)

Answer 5

Anterior Vertebral (Body) Line Posterior Vertebral (Body) Line Spinolaminal Line Post Spinal Line The anterior and posterior lines should be traced to the superior aspect of the odontoid peg. The spinolaminal Line should continue to align with posterior aspect of the foreman magnum. The lines should be smooth and continuous with no breaks or steps

Answer 6

Refers to the dens Distance from the odontoid peg to the C1 ‘body’ Should not be more than 3mm in adults (5mm in children) An increased distance may indicate an odontoid process fracture or disruption to the transverse ligament CT is required to rule out fracture and an MRI if ligament disruption suspected

Answer 7

Soft Tissue ‘A’ C1-C4 Can be up to a third the width of the vertebral body Soft Tissue ‘B’ (C5-C7) C5-C7 Can be up to the width of the vertebral body An increase in the retropharangeal soft tissues may be caused by haemorrhage or oedema due to a fracture or dislocation. The upper limit of normal is: C1 - C4 = 7mm (approx. third of vertebral body) C5 - C7 = 20-22mm (roughly equal to the vertebral body)

Answer 8

Assessment made on AP image Alignment of spinous processes Bifid processes are an exception A step in the alignment can indicate a unilateral facet dislocation Distance between spinous processes The space should not be 50% wider than the one immediately above and below Any change could be the result of anterior cervical dislocation

Answer 9

Formation: Superiorly – upper borders of the pedicles Inferiorly – the lower borders of the pedicles Anteriorly – the anterior aspect of the C2 body Posteriorly – the posterior aspect of the C2 body May appear incomplete inferiorly which is normal A break in the ring at any other point indicates a high probability of # of the odontoid process or body of C2

Answer 10

Assess subluxation/stability Spinal arthropathies Certain patient groups prior to surgery If injury is present, then these must be supervised Assessing the alignment and degree of movement of vertebrae Certain patient groups prior to surgery – RA most commonly. This is to assess intubation risk (as neck is hyperextended to allow for intubation).

Answer 11

Increasing size of vertebral bodies Paraspinal line – caused by interface of lung and mediastinum Left more commonly seen than right Intervertebral disc spaces remain consistent Interpedicular distance consistent as you descend the T-spine Paraspinal line – left is usually more commonly seen due to descending thoracic aorta; left typical extends from the aorta to the diaphragm. Right extends from T8 to T12. Displacement of the paraspinal line may be due to osteophytes, mediastinal fat, or pathology in the posterior mediastinum.

Answer 12

Anterior vertebral body height may be less than posterior vertebral body due to normal wedging Smooth anterior and posterior curves Ribs – consider using a longer exposure time (auto-tomography)

Answer 13

Vertebral bodies should be consistent in height… As should intervertebral disc spaces (L5/S1 is an exception) Interpedicular space increases slightly as we descend the spine Smooth undulation of the vertebral body outline Gentle curve to the anterior lumbar and gentle convexity to the posterior aspect Inclusion of SIJ’s

Answer 14

Absent Pedicle Sign Causes include: Pedicle has been destroyed Congenital abnormality Poor quality image Radiotherapy

Answer 15

Useful for Alignment Detect vertebrae or spinal cord abnormalities Assess inflammation or tumours Monitor damage post-traumatic injury or surgery Look for LBP causes Benefits Very good for the assessment of the spinal cord No ionising radiation Limitations Contraindications Low specificity for some conditions Cost, availability and time factors

Answer 16

Most common injury Esp. in c-spine region Can cause compression fractures of the vertebral bodies Flexion – most common C-spine injuries are caused by hyperflexion (account for approx. 80%). As the head is flexed, the force is focused on the bodies of C4-7 (remember this is where the fulcrum of the neck is in adults). Compression of the vertebral bodies causes anterior wedging. The posterior elements (spinous processes, laminae, ligaments) are placed in tension, which can lead to fractures and tears of theses. Whiplash injuries rear-ended in car

Answer 17

Anterior Subluxation Simple Wedge # Unilateral Interfacet Dislocation Unstable Wedge # Flexion Teardrop # Bilateral Interfacet Dislocation Chance Fracture

Answer 18

Extreme flexion injury Anterior displacement of one vertebral body over another Potential for cord damage UNSTABLE

Answer 19

# of anteroinferior aspect of vertebral body Flexion Teardrop # Extreme flexion with axial loading Potential for cord damage UNSTABLE Flexion and compression injury, typically RTC Teardrop fragment from the anteroinferior aspect of the vertebral body Larger posterior part of the vertebral body is displaced backwards into the spinal canal On x-rays the facet joints and interspinous distances are widened, and disc space may be narrowed. 70% have associated neurological deficit Unstable – complete disruption of ligaments. CT images: The findings are: Abnormal positioning of some of the facet joints due to distraction but no dislocation Additional fracture of the body of C4 The vertical orientation of the fractures of the bodies of C4 and C5 indicate that there was severe axial loading. In fact these vertebral bodies kind of 'exploded' with propulsion of a bone fragment anteriorly (teardrop) and the larger part posteriorly against the spinal cord. Radiology Assistant, n.d.

Answer 20

Unilateral Interfacet Dislocation Flexion and rotation injury Superior facet on one side slides over the inferior facet and becomes locked Often a stable injury even though disruption of the posterior ligament complex is noted. The superior facet on one side slides over the inferior facet and becomes locked. Radiology Assistant, n.d. See an anterior subluxation of c. 25% of the body diameter. MRI can identify if associated disc extrusion (could cause cord compression) The CT confirms the unilateral dislocation. Subluxation at the level of C4C5 with about 25% translation (i.e. anteroposition of 25% of the AP diameter of the vertebral body). Due to the rotation the spinous processes of C4 and C5 seem shorter on the lateral view. On the axial view the left facet joint is normal and on the right side it is inverted due to the dislocation.

Answer 21

Anterior Subluxation Posterior ligaments rupture STABLE AKA “Hyperflexion sprain”. Injury to the posterior ligaments of the spine (ligamentum flavum, interspinous ligament, supraspinous ligament) May be associated injury to the posterior aspect of the intervertebral disc and compression fractures of the anterior vertebral bodies. Causes include RTC, diving into shallow water, falls and direct trauma. Plain X-Ray and CT – may appear normal but may also see an increased interspinous distance, reduced disc space height anteriorly and increased posteriorly, mild anterolisthesis (forward movement of affected vertebrae) MRI – useful to demonstrate disruption of ligaments due to presence of soft tissue oedema, commonly in the interspinous space (space between spinous processes). Can also identify traumatic disc herniation if present. Fracture is stable. Anterior subluxation C5 on C6 – can see increased interspinous space (white arrow) and inferior facets are displaced (black arrow) with loss of superimposition. (Green et al, 1981) MRI anterior subluxation of L4 on L5

Answer 22

Simple Wedge # Pure flexion injury Posterior ligaments remain intact Anterior wedging of 3mm+ Increased density seen due to bony impaction Usually involves upper endplate STABLE A compression fracture of the spinal vertebrae caused by forceful flexion. Nuchal ligament (ligament nuchae) is pulled but remains intact Anterior part of the vertebral body is impacted, becomes wedged (decreased in height) by 3mm+ Will appear on x-ray/CT as an area of increased density due to bony impaction. The fracture is stable.

Answer 23

Unstable Wedge # Anterior wedge # with associated interspinal ligament damage UNSTABLE Hyperflexion injury Anterior wedge fracture which is unstable as a result of the associated posterior column ligamentous tear. Slight increased signal at C6-C7 ligamentum nuchae which may indicate oedema as a result of ligament damage.

Answer 24

Bilateral Interfacet Dislocation Extreme flexion injury Anterior displacement of one vertebral body over another Potential for cord damage UNSTABLE Result of extreme hyperflexion. Anterior dislocation of one vertebral body over another (both facet joints affected) with disruption of the posterior ligament complex, PLL, intervertebral disc, and often the ALL too. Displaced 50% of the diameter of the vertebral body Unstable fracture due to extensive soft tissue damage and dislocated facet joints. MRI The MRI-findings are: Soft tissue swelling anteriorly Disruption of the disc Non-haemorrhagic cord injury

Answer 25

Mechanisms of injury Seatbelt fractures Also fall from height Lumbar region commonly Flexion injury of vertebral body and distraction type injury of the posterior elements Anterior wedge fracture of vertebral body with horizontal fracture through the posterior elements OR distraction of facet joints and spinous processes Flexion and distraction injury Distraction injury – distractive forces cause disruption of the posterior and middle spinal columns. Most common in upper lumbar spine. Often have associated gastrointestional injuries. Unstable injury Radiographic features include an anterior wedge fracture with a horizontal fracture through the posterior elements OR distraction injury of facet joints and spinous processes. Plain radiograph – ‘empty vertebral sign’ results from the vertical separation of the posterior elements displacing the fracture fragments of the vertebral body on the AP view. Loss of anterior vertebral body height (compression). CT – more accurately delineates fracture details. MRI – useful to assess for ligamentous injury and cord injury.

Answer 26

Less common injury, though C-Spine region most affected Vertebrae are forcefully pulled apart, usually as a result of a serious force. Extension – hyperextension causes tension along the anterior longitudinal ligament; this may cause the intervertebral disc space or margin of the vertebral body to tear (avulsion fracture). At the same time, the posterior elements are compressed which may cause fractures to the spinous processes, laminae and facets.

Answer 27

A fracture involving the pars interarticularis of C2 bilaterally, as a result of hyperextension and distraction injury. Also known as traumatic spondylolisthesis of the axis. A result of hyperextension and distraction. Neuro impairment seen in 25% of patients. Most common cause high speed motor vehicle collision (less commonly seen in judicial hangings after which they were named) Radiographic features – bilateral lamina and pedicle fracture at C2 Anterolisthesis of C2 on C3.

Answer 28

Hyperextension MOI Fracture dislocation Affects anterior, middle and posterior spinal columns. Total disruption. Unstable

Answer 29

Axial Compression – result of a high energy axial trauma (e.g. fall onto head, bulls eyeing car window screen, going over the handle bars of a bike). Increased compression causes the structures of the spine to compress and the vertebral body becomes comminuted; increased risk of retropulsion into spinal canal. Fall onto head

Answer 30

Unstable A type of compression fracture related to high-energy axial loading spinal trauma Disruption of the posterior vertebral body cortex with retropulsion into the spinal canal is seen Intervertebral disc is driven into the vertebral body below A compression fracture related to high energy axial loading spinal trauma. Often a fall from height landing on feet, or RTC. Results in disruption of a vertebral body endplate and posterior vertebral body complex. Intervertebral disc is driven into the vertebral body below Retropulsion of posterior cortex fragments into the spinal canal is often associated. Common at L1, but between T9-L5 Often at 2 levels rather than 1 Radiographic features

Answer 31

Burst fracture of the ring of C1 Lateral displacement of both articular masses Typical MOI diving head first into shallow water Asymmetry of odontoid peg and lateral masses # line normally affects both the anterior and posterior arches (CT)

Answer 32

Common injury Often seen in elderly, but also children due to body: head ratio Three types: Type I – avulsion of the tip of the dens Type II – through the base of the dens Type III – Fracture through the body of the axis and possibly facets

Answer 33

Type III – Fracture through the body of the axis and possibly facets, SOMETIMES UNSTABLE, better healing A type III odontoid fracture is a fracture through the body of the C2 vertebrae and may involve a variable portion of the C1 and C2 facets. Type III odontoid fractures occur secondary to hyperextension or hyperflexion of the cervical spine in a similar manner to type II odontoid fractures. The difference is where the fracture line occurs.

Answer 34

Type II – through the base of the dens, most common, ALWAYS UNSTABLE, poor healing (64% non-union as more likely to move out of position) A type II odontoid fracture is a fracture through the base of the odontoid process. This injury occurs most typically when there is an excessive extension of the cervical spine, and the anterior arch of C1 pushes dorsally (backward) with sufficient force on the odontoid process (dens) to fracture the odontoid process at its base. Type II odontoid fractures can also occur with hyperflexion of the neck and the transverse ligament, pushing the odontoid process forward to the point of fracture.

Answer 35

Type I – avulsion of the tip of the dens, rare, STABLE A type I odontoid fracture occurs when the rostral tip of the odontoid process is avulsed (broken or torn off). This injury commonly occurs due to pulling forces from the apical ligament attachment to the odontoid process. The apical ligament attaches the tip of the odontoid process to the foramen magnum (skull base).

Answer 36

Scoliosis: an abnormal lateral curvature of the spine. Common in young individuals and is often idiopathic and asymptomatic. Associated symptoms can include back pain, mobility issues and respiratory and cardiac problems. Signs include uneven hips, arms or legs, rib prominence, uneven muscles and slow nerve reaction.

Answer 37

common measure to determine and track progression of scoliosis. In place since 1948. To determine the Cobb angle, you must first determine where the curve starts and ends. From the end plate of each vertebrae you draw a line until these meet and measure the angle. Management will depend on this angle; if ‘mild’ observation and/or bracing maybe considered. If the angle is grater than 50° then surgical intervention might be necessary (anterior and/or posterior fusion; Harrington Rods were commonly before this).

Answer 38

Broad term that covers benign lesions, primary bone tumours and secondary metastatic disease Examples: Aneurysmal bone cyst (ABC) Osteoblastoma Multiple Myeloma

Answer 39

Benign, expansile lesion Composed of numerous blood-filled channels Common in children (<16 years old) Common in long bones (approx. 60% occur here). Occurrence in spine 20-30%. All images from a 16 y/o patient with an ABC affecting the left side of the T10 vertebral body, pedicle and transverse process.

Answer 40

Rare, bone forming tumour, that is locally aggressive More frequently affect the axial skeleton (~40%) Plain radiograph – expansile, lytic lesions with a sclerotic edge. CT - similar to the radiograph, lesions are often demonstrated as predominantly lytic. Internal matrix is better appreciated on CT MRI – features can be non-specific and often overestimate the size of the lesion. Typically appears dark (has low intensity signal) on both T1 and T2. However, a high signal on T2 may be seen in surround bone marrow and soft tissue oedema. Highly vascularised tumour so contrast enhancement is useful. Nuclear medicine – Tc-99m bone scans can show high uptake, but this is non-specific (intake will be high in any area with increased bone turnover)

Answer 41

Most common primary malignant bone tumour Arises from red marrow Clinical presentation: Bone pain Anaemia Hypercalcaemia Renal failure Distribution mirrors red marrow sites More likely to occur in those over 40 years old (typically onset btw. 50-70 y/o). More likely to occur in males than females. MRI demonstrates complete replacement of this vertebral bone marrow, with it appearing of lower intensity that skeletal muscle Plain radiograph – A skeletal survey (lateral skull to inc. C-spine, lateral T-spine, lateral L-spine, AP pelvis, AP humeri, AP femora, CXR) is essential not only for the diagnosis of multiple myeloma but also in pre-empting potential complications (e.g. pathological fracture). ~40% bone destruction is required for lesion detection; lesions are lytic, sharply defined, and can appear punched out. CT – Whole-body low dose CT is more accurate than a skeletal survey (~70% sensitivity), but comes with a radiation dose increase. MRI – more sensitive in detecting multiple lesions compared to both plain film x-ray and CT (sensitivity 70-100%). MRI sequences that allow for bone marrow evaluation are most commonly utilised (T1 and T2). T1 typically appears dark (low signal intensity) due to the loss of fatty tissue within marrow. Whereas on T2 it appears grey (as signal intensity is intermediate).

Answer 42

Spondylosis is the term used for osteoarthritis of the spine. It is an ageing, wear and tear type process, characterised by degenerating and narrowing discs and bones spurs (osteophytes) forming around joints.

Answer 43

Spondylolysis relates specifically to a defect or fracture through the bone where the pedicle and lamina join, resulting in a weakening of the vertebral arch. This area is known as the ‘pars interarticularis’. Defects can be unilateral or bilateral and may lead to compromises in the vertebra maintaining their normal alignment in the vertebral column.. ‘Scottie dogs’ on oblique x-rays. A collar is indicative of a #pars interarticularis defect

Answer 44

Spondylolithesis - This is the term used to describe one vertebral body slipping out of place in relation to another. Can be caused by spinal degeneration (spondylosis) or a pars interarticularis defect (spondylolysis) One vertebra slips forward on the adjacent vertebra Developing stenosis of the vertebral canal Nerve impingement Most common at L4/5/S1

Answer 45

Ankylosis - The stiffening and immobility of a joint The bones are fusing together abnormally Ankylosing spondylitis An inflammatory type of arthritis (rather than osteoarthritis) that primarily affects the spine (but can affect other joints) Large bone spurs (osteophytes) join one vertebra to the next causing a ‘bamboo’ cane type appearance and pathological fusion.

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Spine part 1 and part 2 Flashcards

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