Autopsy & forensics
General
Spine and spinal cord traumatic injury
Authors: Michel Tawil, M.D., Christine E. Fuller, M.D.
Resident / Fellow Advisory Board: Lorenzo Gitto, M.D.
Deputy Editor-in-Chief: Patricia Tsang, M.D., M.B.A.
Last author update: 25 April 2023
Last staff update: 25 April 2023
Copyright: 2023, PathologyOutlines.com, Inc.
PubMed Search: Spine and spinal cord traumatic injury
Table of Contents
Definition / general | Essential features | Epidemiology | Pathophysiology | Autopsy findings | Microscopic findings | Medicolegal considerations | Additional references | Board review style question #1 | Board review style answer #1Cite this page: Tawil M, Fuller CE. Spine and spinal cord traumatic injury. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/forensicsneuropathologyspinalcord.html. Accessed April 26th, 2024.
Definition / general
- Spinal cord injuries may lead to disruption to the axonal tracts running the length of the cord, leading to loss of function and increased rates of mortality and morbidity
- Clinical symptom complex relates directly to the level and severity of cord injury
Essential features
- Traumatic injury to the spinal cord may take the form of localized compression, contusion, laceration, hemorrhage, flexion / extension injury or even direct penetrating injury from a knife or bullet
- Vertebral fractures and dislocations of the vertebral column may result in concomitant spinal cord injury
Epidemiology
- Globally, between 250,000 and 500,000 patients each year sustain spinal cord injuries (J Spinal Cord Med 2016;39:493)
- In the United States, there are 17,000 new cases of spinal cord injury annually
- Males between the ages of 16 to 30 years are the most prone (Hodler: Diseases of the Brain, Head and Neck, Spine 2020-2023, 1st Edition, 2020)
- 38% of new spinal cord injury cases yearly are due to motor vehicle accidents, followed by falls at 30%, violent encounters at 13%, sports injuries at 9% and iatrogenesis at 5% (J Spinal Cord Med 2016;39:493)
- Cervical cord injuries may result from whiplash type injuries, including in the context of shaking of infants
- Up to 67% of spinal cord injuries are cervical, with ~25% thoracic and 10% involving lumbar cord
Pathophysiology
- Injury to the upper cervical spine and cord
- Anteroposterior shear force or rotational force → disruption of the transverse ligament of C1 → atlantoaxial subluxation with or without odontoid fracture and no cord injury (J Am Acad Orthop Surg 2002;10:271)
- Compressive vertex impacts (falls) → compression fracture of the anterior and posterior arches of C1 with lateral displacement of the fragments to C2 without cord injury (J Athl Train 2012;47:489)
- Forcible hyperextension of the neck (judicial hangings or motor vehicle accidents) → fracture of pedicles of C2 → anterior dislocation of C2 or C3 with or without odontoid fracture
- Ring fractures (J Korean Neurosurg Soc 2014;56:534)
- Occur at the base of the skull leading to separation of the foramen magnum from the skull
- The spine pushes against the base of the skull leading to pontomedullary junction lacerations
- Caused by substantial blunt force trauma (e.g., motor vehicle collision) and commonly associated with temporal bone fracture
- Causes of death include dislocation of the atlanto-occipital junction, hemorrhage in the pons and brainstem injury
- Injury to the middle and lower cervical spine (C4 - C8)
- Most common type of nonfatal spinal cord injury
- More severe than upper cervical spine injuries
- Spinal ligamentous injury is always present
- Hyperflexion injuries (blows to the back, shallow water diving, vehicle rollover) → teardrop fracture (pinching off of the anterior part of the vertebral body and backward displacement of posterior part into the spinal canal and cord) (Asian Spine J 2009;3:73)
- Combination of rotational movements (automobile accident) → subluxation and spinal canal impingement
- One of the most immediate factors determining survival rate is respiratory control (Spine (Phila Pa 1976) 2001;26:S27, Front Neurol 2019;10:282)
- Injury at C4 or higher → loss of phrenic nerve control over diaphragm → total dependence on accessory muscles
- Other existing conditions like organ failure, shock lung, air embolism or hemothorax might overwhelm the lungs, leading to death
- Quadriplegia may ensue if injury is above level of emergence of the brachial plexus roots
- Paraplegia may ensue if injury is below level of emergence of brachial plexus roots (T1 or T2)
- Injury below C4 → bladder and bowel function disability → recurrent and chronic cystitis and pyelonephritis
- Injury at C4 or higher → loss of phrenic nerve control over diaphragm → total dependence on accessory muscles
- Spinal cord injury without radiographic abnormality (SCIWORA) (Adv Orthop 2018;2018:7060654)
- An entity based on clinical signs of posttraumatic spinal cord injury without evidence of fracture or malalignment on imaging
- MRI is now a preferable modality because of its superior ability to identify soft tissue lesions that may not be visualized in plain radiographs or CT
- Mostly seen in children rather than adults, due to increased head to body ratio and immaturity of neck musculature
- 2 hit hypothesis: initial hyperextension or hyperflexion of the neck leads to a subsequent secondary insult that worsens the cellular reaction to the primary injury
- Craniocerebral trauma (J Neurosurg 1971;34:603)
- Spinal cord injuries occurring in conjunction with brain trauma resulting in sudden death
- Mostly high cervical spinal cord trauma with pontomedullary or brain stem injury
- Spinal cord injuries occurring in conjunction with brain trauma resulting in sudden death
- Injury to the thoracic spine
- Upper thoracic: higher resistance to injury due to the rib cage and costovertebral ligaments → greater force required
- Lower thoracic: vulnerable to rotational and flexion force injuries due to higher flexibility and lack of stability of lateral ribs
- Injury to the lumbar and lumbosacral spine
- Compression injuries with burst fractures (breaks of vertebra in multiple directions) are common
- Sitting position injuries, such as in airplane crashes (Korean J Neurotrauma 2015;11:195)
- Common to have fractures in this location related to osteoporosis and metastatic disease (pathologic fractures)
Autopsy findings
- Soft tissue disruption and hemorrhage are common findings at the site of bone fracture or ligament tears
- Grossly evident damage to the cord may take the form of indentation and edema to hemorrhage or disruption (Hodler: Diseases of the Brain, Head and Neck, Spine 2020-2023, 2020)
- Acute fatal cases of craniospinal trauma → look for perivascular petechial intramedullary hemorrhages with an otherwise normal look to the spinal cord (Radiopaedia: Traumatic Spinal Cord Injury [Accessed 11 April 2023])
- Assessment of spine / spinal cord injury may require removing the affected portion of the vertebral column en bloc to preserve anatomic relationships (J Orthop Sci 2006;11:3)
Microscopic findings
| Time and course of injury | |
| Time interval (postinjury) | Microscopic findings |
| 0 - 1 hours | Minimal to no changes |
| 4 hours | Central necrosis |
| 8 - 24 hours | Necrosis starts spreading peripherally |
| Within 24 hours | Polymorphonuclear cells dominate |
| Within 1 month | Macrophages dominate |
| Months to years | Residual cystic lesion with variable amount of neovascularization and gliosis |
- Acute spinal cord injury will show a mixture of edema, axonal spheroids, hemorrhage and infarct
- As time passes, the area of damage will expand with progressive cavitation and subsequent tract degeneration
Medicolegal considerations
- High mental and emotional burden on victims of disabling spinal cord injury → depression and suicide are among the most common complications of spinal cord injury (J Spinal Cord Med 2007;30:S76)
- Circumstances in which legal issues can arise include spinal injuries after chiropractic management, in suspected child abuse cases, complications of spinal surgery and in sports and training (World Neurosurg 2021;149:e108, Int J Legal Med 2021;135:1481)
Additional references
Board review style question #1
Traumatic spinal cord injury most frequently involves which of the following regions?
- Filum terminale
- Lumbar cord
- Mid to lower cervical cord
- Thoracic cord
- Upper cervical cord
Board review style answer #1
C. Mid to lower cervical cord. The mid to lower cervical levels of the spinal cord are the most frequent to be involved in traumatic spinal cord injury due to this area being the most mobile relative to adjoining structures. It may thus be subjected to motions including hyperflexion, hyperextension, hyperrotation or compression.
Injuries to the upper cervical cord are less common due in part to more space around the cord in this region, as well as restriction of motion by the transverse ligament of the atlas. The thoracic rib cage and costovertebral ligaments provide added stability to the thoracic spine. The lumbar region would be more prone to injury due to less lateral stability and more flexibility than the thoracic region, though still is less susceptible to injury than the mid / lower cervical region. The filum terminale is a fibrous band connecting the lower end of the cord (conus medullaris) to the posterior coccyx and not typically injured without disruption / injury of adjoining structures.
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Reference: Spine and spinal cord traumatic injury
Injuries to the upper cervical cord are less common due in part to more space around the cord in this region, as well as restriction of motion by the transverse ligament of the atlas. The thoracic rib cage and costovertebral ligaments provide added stability to the thoracic spine. The lumbar region would be more prone to injury due to less lateral stability and more flexibility than the thoracic region, though still is less susceptible to injury than the mid / lower cervical region. The filum terminale is a fibrous band connecting the lower end of the cord (conus medullaris) to the posterior coccyx and not typically injured without disruption / injury of adjoining structures.
Comment Here
Reference: Spine and spinal cord traumatic injury
