Introduction to Gunshot Injury Rehabilitation: Difference between revisions
No edit summary |
No edit summary |
||
(27 intermediate revisions by 2 users not shown) | |||
Line 1: | Line 1: | ||
<div class="editorbox"> | <div class="editorbox"> | ||
'''Original Editor '''- [[User: | '''Original Editor '''- [[User:Zafer Altunbezel|Zafer Altunbezel]] | ||
'''Top Contributors''' - {{Special:Contributors/{{FULLPAGENAME}}}} | '''Top Contributors''' - {{Special:Contributors/{{FULLPAGENAME}}}} | ||
</div> | </div> | ||
== Introduction == | == Introduction == | ||
Gunshot injuries are one of the most common injury patterns in conflict settings, with civilians becoming more vulnerable in 21st-century armed conflicts. Gunshot injuries are high-energy injuries which can cause significant tissue damage, paralysis or death. The extent of the injury depends on a number of factors. Rehabilitation professionals should have an understanding of the potential consequences and appropriate management strategies throughout each phase of rehabilitation to enhance patient outcomes. | |||
== Definition of | == Definition of Gunshot Injury == | ||
<blockquote> | <blockquote>A gunshot injury is "the penetrating injury and its related consequences caused by a projectile from a firearm."<ref name=":2">Altunbezel Z. Introduction to Gunshot Injury Rehabilitation Course. Plus, 2024. </ref></blockquote> | ||
== Epidemiology == | == Epidemiology == | ||
The epidemiology of gunshot injuries is difficult to assess, and it varies based on the population, conflict set, country, characteristics of the conflict, and time it occurred:<ref name=":2" /> | |||
* | * Wild et al. aimed to describe "conflict-related injuries sustained by civilians and local combatants in twenty-first century conflict".<ref name=":4">Wild H, Stewart BT, LeBoa C, Stave CD, Wren SM. [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7223167/pdf/268_2020_Article_5428.pdf Epidemiology of Injuries Sustained by Civilians and Local Combatants in Contemporary Armed Conflict: An Appeal for a Shared Trauma Registry Among Humanitarian Actors]. World J Surg. 2020 Jun;44(6):1863-1873.</ref> They found that:<ref name=":4" /> | ||
** gunshot injuries caused 22% of injuries in civilians and local combatants | |||
** gunshot injuries are the second most common mechanism of injury among US military personnel during armed conflict, causing 19.9% of injuries | |||
** 22% gunshot | * Wild et al.<ref name=":4" /> also found that urban and semi-urban settings have higher rates of gunshot injuries | ||
** 42.2% of injuries | ** gunshot injuries accounted for 42.2% of injuries in urban settings | ||
** 7.5% of injuries | ** gunshot injuries accounted for 26.7% of injuries in semi-urban settings | ||
** gunshot injuries accounted for 7.5% of injuries in rural settings | |||
* | * in the USA in 2020, over 45,000 deaths were attributed to gun-related injuries<ref name=":3">Stewart S, Tunstall C, Stevenson T. Gunshot wounds in civilian practice: a review of epidemiology, pathophysiology and management. Orthopaedics and Trauma 2023; 37(4):216-221.</ref> (i.e. 13.6 per 100,000 people<ref>Menezes JM, Batra K, Zhitny VP. [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10445625/ A nationwide analysis of gunshot wounds of the head and neck: morbidity, mortality, and cost]. J Craniofac Surg. 2023 Sep 1;34(6):1655-60. </ref>) | ||
== Firearms and Gunshot | == Types of Firearms and Severity of Gunshot Injury == | ||
The wounding potential of a firearm depends on various factors, including: | |||
* | * the type of the firearm (muzzle velocity) | ||
* | * the type of bullet | ||
* | * the distance to the target | ||
* the size of the pellets | |||
* | |||
Based on the muzzle velocity, | Based on the muzzle velocity, firearms can be divided into low-velocity, medium-velocity, or high-velocity firearms.<ref name=":2" /> | ||
=== Classification === | |||
Gunshot injuries can be classified based on the type of firearm and the Gustilo-Anderson open fracture classification. You can find out more about this classification system here: [https://www.orthobullets.com/trauma/1003/gustilo-classification Gustilo Classification]. | |||
=== Low-Velocity Firearms === | === Low-Velocity Firearms === | ||
Low-velocity firearms, including small handguns and pistols, have a muzzle velocity of less than 1200 feet.<ref name=":2" /> They tend to cause injuries that are similar to Gustilo-Anderson Type I and Type II injuries.<ref name=":1">Gustilo Classification. Available from https://www.orthobullets.com/trauma/1003/gustilo-classification [last access 14.04.2024]</ref> | |||
* Type I<ref name=":1" /><ref name=":11">Kim PH, Leopold SS. [https://journals.lww.com/clinorthop/fulltext/2012/11000/gustilo_anderson_classification.48.aspx In brief: Gustilo-Anderson classification]. [corrected]. Clin Orthop Relat Res. 2012 Nov;470(11):3270-4. doi: 10.1007/s11999-012-2376-6. Epub 2012 May 9. Erratum in: Clin Orthop Relat Res. 2012 Dec;470(12):3624. Erratum in: Clin Orthop Relat Res. 2019 Oct;477(10):2388. </ref> | |||
** low energy | |||
** wound size is less than one centimetre | |||
** minimal soft tissue damage and fracture comminution | |||
** wound is clean | |||
** no neuromuscular injury | |||
* Type II<ref name=":1" /><ref name=":11" /> | |||
** moderate energy | |||
** wound size is between 1 and 10 centimetres | |||
** moderate soft tissue damage and fracture comminution | |||
** moderate wound contamination | |||
** no neuromuscular injury | |||
=== Medium-Velocity Firearms === | |||
Medium-velocity firearms, including high-calibre handguns and shotguns, have a muzzle velocity between 1200-2000 feet per second.<ref name=":2" /> However, wound severity depends on various factors, including the distance and projectile.<ref name=":2" /><ref name=":5" /> | |||
Example: shotguns are medium-velocity firearms, but because of the "large total mass of their lead pellets can increase their kinetic energy dramatically. [...] Depending on the distance to the target and the size of pellets, shotguns can reflect the wounding potential of high-velocity firearms or multiple low-velocity weapons. [...] Very close proximity of shotgun to the target (< 2 m) results in not only the pellet projection, but also shell fragments and wadding."<ref name=":10">Gugala Z, Lindsey RW. [https://journals.lww.com/clinorthop/fulltext/2003/03000/classification_of_gunshot_injuries_in_civilians.7.aspx Classification of Gunshot Injuries in Civilians. Clinical Orthopaedics and Related Research] 2003;408():p 65-81.</ref> | |||
=== High-Velocity Firearms === | |||
High-velocity firearms, including military and hunting rifles, have a muzzle velocity greater than 2000 feet per second,<ref name=":2" /> and they are associated with more substantial tissue damage.<ref name=":5">Baum GR, Baum JT, Hayward D, MacKay BJ. [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9462949/pdf/orr-14-293.pdf Gunshot Wounds: Ballistics, Pathology, and Treatment Recommendations, with a Focus on Retained Bullets.] Orthop Res Rev. 2022 Sep 5;14:293-317. </ref> They tend to cause Gustilo-Anderson Type III wounds.<ref name=":1" /> | |||
* Type III (A, B, or C)<ref name=":1" /><ref name=":11" /> | |||
** high energy | |||
** wound size is usually greater than 10 centimetres | |||
** extensive soft tissue damage | |||
** severe fracture comminution | |||
** extensive wound contamination | |||
** periosteal stripping present | |||
** may require flap coverage (III B and III C) | |||
** exposed fracture with arterial damage that requires repair may be present (III C) | |||
[[File:Gunshot Injury Mechanism.png|thumb|400x400px|<small>Figure 1. Mechanism of gunshot injury.</small>]] | |||
== Mechanism of Gunshot Injuries == | |||
* The projectile hits the body and transfers its kinetic energy and heat to the tissues | |||
* This creates a permanent cavity approximately the size of the projectile's cross-sectional area | |||
* The momentarily extreme pressure around the projectile's trajectory can create a vortex effect<ref name=":2" /> | |||
* This vortex effect causes the tissue around the projectile's trajectory to momentarily stretch out, forming a temporary cavity, before contracting back<ref name=":2" /> | |||
* The projectile may exit the body, usually creating a bigger exit point, remain in the body or change direction | |||
* Sometimes the projectile fragments or explodes inside the body, causing further damage<ref name=":2" /> | |||
== Effects of Gunshot Injuries == | |||
<blockquote>"While the tissues in the primary cavity sustain direct injury due to energy transfer, surrounding tissues within the temporary cavity sustain secondary injuries due to burns and extreme stretching."<ref name=":2" /></blockquote>[[File:Gunshot Injury Cross-Section.001.jpeg|thumb|<small>Figure 2. Cross-section of a gunshot injury.</small>]]Gunshot wounds can have a range of effects, including diffuse soft tissue damage, muscle damage, nerve injury, vascular injury / haemorrhage, bone injury and severe pain.<ref name=":0">Moriscot A, Miyabara EH, Langeani B, Belli A, Egginton S, Bowen TS. [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7997931/pdf/41536_2021_Article_127.pdf Firearms-related skeletal muscle trauma: pathophysiology and novel approaches for regeneration.] NPJ Regen Med. 2021 Mar 26;6(1):17.</ref> These injuries are discussed in more detail below. | |||
==== Soft-tissue Injury ==== | |||
The permanent cavity or temporary cavitation causes soft tissue damage:<ref name=":0" /> | |||
* tissues in the primary (permanent) cavity are injured by the projectile and extreme kinetic energy transfer<ref name=":2" /> | |||
* tissues in the temporary cavity are "destroyed by projectile compression and shearing that leaves a projectile trail"<ref name=":0" /> | |||
There may be partial or complete damage to the soft tissues, including ruptures, lacerations, internal burns and scarring in the later stages.<ref name=":2" /> | |||
==== Muscle Injury ==== | |||
<blockquote>"Skeletal muscle is suggested to be more sensitive to permanent cavitation, with temporary cavitation thought to induce less damage (unless the vasculature is disrupted) due to skeletal muscle’s inherent elasticity."<ref name=":0" /></blockquote>Skeletal muscles can be affected by laceration, contusion or crush injury, denervation, haemorrhage, ischaemia, burns, and volumetric muscle loss. Primary trauma can be complicated by secondary trauma, including:<ref name=":0" /> | |||
* infection and sepsis as a result of contamination from the bullet or debris accumulated on clothing or the skin | |||
* surgical debridement of damaged tissue | |||
* excessive physical movement | |||
Immobilisation and nutrient deficiency can lead to volumetric muscle loss after a gunshot injury. | |||
==== Nerve Injury ==== | |||
Gunshot injuries can cause:<ref name=":6">Shields LBE, Iyer VG, Zhang YP, Shields CB. [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10808781/pdf/fneur-14-1333763.pdf Gunshot-related nerve injuries of the upper extremities: clinical, electromyographic, and ultrasound features in 22 patients]. Front Neurol. 2024 Jan 11;14:1333763. </ref> | |||
* direct transection of the nerve | |||
* indirect injury from thermal damage, shock waves, and laceration from fracture fragment displacement | |||
* compression due to swelling or subacute scar formation | |||
Therefore, gunshot-related injuries can cause axonotmesis, neuropraxia and neurotmesis.<ref>Straszewski AJ, Schultz K, Dickherber JL, Dahm JS, Wolf JM, Strelzow JA. Gunshot-Related Upper Extremity Nerve Injuries at a Level 1 Trauma Center. J Hand Surg Am. 2022 Jan;47(1):88.e1-88.e6. </ref> '''Axonotmesis''' "describes the range of peripheral nerve injuries that are more severe than a minor insult, such as those resulting in neurapraxia, yet less severe than the transection of the nerve, as observed in neurotmesis."<ref>Chaney B, Nadi M. [https://www.ncbi.nlm.nih.gov/books/NBK562304/ Axonotmesis]. 2023 Sep 4. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan–. </ref> '''Neuropraxia''' is the "focal segmental demyelination at the site of injury without disruption of axon continuity and its surrounding connective tissues."<ref>Biso GMNR, Munakomi S. Neuroanatomy, Neurapraxia. [Updated 2022 Oct 24]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from https://www.ncbi.nlm.nih.gov/books/NBK557746/ [last access 16.04.2024]</ref> '''Neurotmesis''' is a "complete transection of a peripheral nerve."<ref>Matos Cruz AJ, De Jesus O. Neurotmesis. [Updated 2023 Aug 23]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK559108/</ref> | |||
The most frequently affected nerves in the upper extremities are the ulnar nerve and the brachial plexus.<ref name=":6" /> Sheilds et al. also note that, in gunshot injuries, "vascular injury and fractures increase the risk of nerve injury".<ref name=":6" /> | |||
==== Vascular Injury / Haemorrhage ==== | |||
Blood vessels can be directly injured or affected by secondary circulatory compromise.<ref name=":2" /> Vascular injury can lead to blood loss or haemorrhage (internal or external). A haemorrhagic area can form around irreversibly damaged tissue following gunshot injury. This extra vacation zone "is characterized by interstitial bleeding but the absence of macroscopically evident tissue destruction."<ref>Stefanopoulos PK, Hadjigeorgiou GF, Filippakis K, Gyftokostas D. [https://core.ac.uk/download/pdf/82808812.pdf Gunshot wounds: A review of ballistics related to penetrating trauma]. Journal of Acute Disease 2014;3(3):178-185.</ref>[[File:Highly-comminuted-fracture-gun-shot-injury.jpg|thumb|<small>Figure 3. Highly comminuted fracture-gunshot injury. Image courtesy of Dr. Matt Skalski, [[/radiopaedia.org/|Radiopaedia.org]]; rID:46134</small>]] | |||
=== | ==== Bone Injury ==== | ||
Gunshot injuries usually result in '''comminuted, displaced fractures''':<ref name=":2" /> | |||
* caused by high-energy ballistic penetration | |||
* a secondary effect of cavitation associated with the fluid properties of bone marrow | |||
* associated with a high incidence of secondary complications, including infection and nonunion<ref name=":9">Yeganeh A, Amiri S, Otoukesh B, Moghtadaei M, Sarreshtedari S, Daneshmand S, Mohseni P. [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9194713/pdf/ABJS-10-453.pdf Characteristic Features and Outcomes of Open Gunshot Fractures of Long-bones with Gustilo Grade 3: A Retrospective Study.] Arch Bone Jt Surg. 2022 May;10(5):453-458.</ref> | |||
** the rate of infection is higher in patients with a skin flap<ref name=":9" /> | |||
** the rate of nonunion is higher in patients who have vascular injuries<ref name=":9" /> | |||
A '''drill-hole effect''' is often caused by low-energy injuries to porous, low-density / cancellous bone<ref name=":10" />: | |||
* | * more common in the pelvis, distal femur, proximal humerus and spine<ref name=":10" /> | ||
* | * low-energy ballistic penetration | ||
* | * affects the metaphyseal region of long bones | ||
Unicortical fractures: | |||
* can be due to "low-energy missile impact that creates only a tangential bone defect"<ref name=":10" /> | |||
Transverse or spiral fractures: | |||
* | * can be caused by lower-energy gunshots to dense and highly-mineralised diaphyseal cortical bone | ||
Gunshot injuries can result in secondary injuries (e.g. a fall), which can also result in fracture.<ref name=":10" /><ref>Smith HW, Wheatley KK Jr. Biomechanics of femur fractures secondary to gunshot wounds. J Trauma. 1984 Nov;24(11):970-7. </ref> | |||
== | ==== Pain ==== | ||
* Patients with gunshot wounds in a combat setting have a high risk of chronic pain, "45% higher than the general population in civilian trauma patients"<ref name=":8">Kuchyn I, Horoshko V. [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9903440/pdf/12871_2023_Article_2005.pdf Chronic pain in patients with gunshot wounds.] BMC Anesthesiol. 2023 Feb 7;23(1):47.</ref> | |||
* 70% of individuals with gunshot injuries develop chronic pain<ref>Horoshko V. Value of the number of injured anatomical parts of the body and surgeries for pain chronicity in patients with gunshot wounds and blast injuries. Emergency Medicine 2023;19(3):141–143. </ref> | |||
* Kuchyn and Horoshko<ref name=":8" /> found that individuals who were injured by gunshots in three or more areas had a higher percentage of chronic pain than those with injuries to one or two areas | |||
* Complex regional pain syndrome (CRPS) can occur after traumatic events, including gunshot injuries<ref>Tieppo Francio V, Barndt B, Towery C, Allen T, Davani S. [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6202970/pdf/bcr-2018-224702.pdf Complex regional pain syndrome type II arising from a gunshot wound (GSW) associated with infective endocarditis and aortic valve replacement.] BMJ Case Rep. 2018 Oct 16;2018:bcr2018224702.</ref> | |||
== | == Determinants of Injury Severity == | ||
"Gunshot | * Projectile: velocity, mass, shape, calibre, material, yawing and impact distance:<ref name=":0" /><ref name=":2" /> | ||
** mass / shape: as projectile diameter / length increase, more damage is likely | |||
** velocity: as the velocity increases, the amount of kinetic energy dramatically increases, causing more harm | |||
** impact distance: as projectiles travel longer distances, they lose more of their kinetic energy and cause less harm, whereas even smaller projectiles from close distances can cause extensive damage | |||
** yaw is "the angle between the long axis of the bullet and its direction of flight."<ref name=":7">Gunshot Wounds: Management and Myths (2012). Available from https://www.reliasmedia.com/articles/76797-gunshot-wounds-management-and-myths [last access 16.04.2024]</ref> As the distance increases, the projectile loses its stability and starts to yaw off. While this decreases the amount of kinetic energy transfer, it can increase the cross-sectional area, causing more damage<ref name=":2" /> | |||
* Type of tissue: density, elasticity, and thickness<ref name=":0" /> | |||
** high elasticity and low density equal less damage<ref name=":7" /> | |||
** skin has a high degree of elasticity and relatively low density | |||
** lungs have a much lower density and absorb less energy | |||
** bones are dense and absorb more energy | |||
* The entry and exit points and trajectory within the body<ref name=":2" /> | |||
** if they are close to the nervous plexus, more severe damage can occur | |||
** if they are close to main arteries or veins, the clinical presentation can be more complicated | |||
*Projectile fragmentation | |||
**more fragments = more than one trajectory within the body, which results in more severe internal issues to manage in the following days and months<ref name=":2" /> | |||
== Potential Challenges and Secondary Complications of Gunshot Injuries == | |||
The management of the secondary complications related to the gunshot injury is complex. Early intervention and in-depth knowledge are required to maximise rehabilitation outcomes. | |||
Some secondary complications of gunshot injuries are listed below:<ref name=":2" /> | |||
* '''[[Contractures|joint contractures]]''' can develop as a result of periods of immobilisation after comminuted and complex open fractures that require external / internal fixation | |||
* '''[[Myofascial Pain|myofascial]], [[Chronic Pain|chronic]], or [[Neuropathic Pain|neuropathic pain]]''' can develop due to internal scarring, internal burns, wound or bone infection | |||
* '''peripheral nerve injuries''' that are initially undetected due to heterogeneity and the conditions on the field may require referral to a specialist | |||
* '''[[Deep Vein Thrombosis|deep vein thrombosis]] or different types of embolism''' | |||
* '''[[Complex Regional Pain Syndrome (CRPS)|complex regional pain syndrome]] (causalgia)''' known as military pain syndrome - "tends to affect combat soldiers after they sustain wartime injuries from blasts and gunshots"<ref>Nelson CN, Glauser G, Kessler RA, Jack MM. Causalgia: a military pain syndrome. Neurosurgical Focus 2022;53(3): E9.</ref> | |||
* '''[[Central Sensitisation|central sensitisation]]''' | |||
* '''[[Mental Health Issues and Rehabilitation|mental health issues]],''' including '''post-traumatic stress disorder, anxiety or [[depression]],''' which tend to worsen over time with long-term declines in mental health status<ref>Greenspan AI, Kellermann AL. Physical and psychological outcomes 8 months after serious gunshot injury. J Trauma. 2002 Oct;53(4):709-16. </ref> | |||
== | == Skills and Knowledge Required to Treat Gunshot Injuries == | ||
It is recommended that rehabilitation professionals treating gunshot injuries have a solid understanding of the following topics:<ref name=":2" /> | |||
* neuroanatomy | |||
** to perform a neurological examination | |||
** to plan treatment | |||
** to recognise signs and symptoms that warrant referral to speciality services | |||
* pain neuroscience | |||
** to provide pain education to help manage chronic / persistent pain | |||
*clinical reasoning | |||
**to manage complex cases | |||
**to participate in / lead a multidisciplinary team | |||
*manual skills | |||
**to help manage joint contractures, internal scarring, and neurogenic compromise | |||
== Resources == | |||
*[https://www.orthobullets.com/Site/ElasticSearch/StandardSearchTiles?contentType=6&search=Gun%20Shot%20Wounds Gun Shot Wounds] | |||
== References == | == References == | ||
<references /> | <references /> | ||
[[Category:Course Pages]] | |||
[[Category:SRSHS Course Pages]] | |||
[[Category:Injury]] |
Revision as of 12:07, 27 April 2024
Original Editor - Zafer Altunbezel
Top Contributors - Ewa Jaraczewska, Jess Bell and Kim Jackson
Introduction[edit | edit source]
Gunshot injuries are one of the most common injury patterns in conflict settings, with civilians becoming more vulnerable in 21st-century armed conflicts. Gunshot injuries are high-energy injuries which can cause significant tissue damage, paralysis or death. The extent of the injury depends on a number of factors. Rehabilitation professionals should have an understanding of the potential consequences and appropriate management strategies throughout each phase of rehabilitation to enhance patient outcomes.
Definition of Gunshot Injury[edit | edit source]
A gunshot injury is "the penetrating injury and its related consequences caused by a projectile from a firearm."[1]
Epidemiology[edit | edit source]
The epidemiology of gunshot injuries is difficult to assess, and it varies based on the population, conflict set, country, characteristics of the conflict, and time it occurred:[1]
- Wild et al. aimed to describe "conflict-related injuries sustained by civilians and local combatants in twenty-first century conflict".[2] They found that:[2]
- gunshot injuries caused 22% of injuries in civilians and local combatants
- gunshot injuries are the second most common mechanism of injury among US military personnel during armed conflict, causing 19.9% of injuries
- Wild et al.[2] also found that urban and semi-urban settings have higher rates of gunshot injuries
- gunshot injuries accounted for 42.2% of injuries in urban settings
- gunshot injuries accounted for 26.7% of injuries in semi-urban settings
- gunshot injuries accounted for 7.5% of injuries in rural settings
- in the USA in 2020, over 45,000 deaths were attributed to gun-related injuries[3] (i.e. 13.6 per 100,000 people[4])
Types of Firearms and Severity of Gunshot Injury[edit | edit source]
The wounding potential of a firearm depends on various factors, including:
- the type of the firearm (muzzle velocity)
- the type of bullet
- the distance to the target
- the size of the pellets
Based on the muzzle velocity, firearms can be divided into low-velocity, medium-velocity, or high-velocity firearms.[1]
Classification[edit | edit source]
Gunshot injuries can be classified based on the type of firearm and the Gustilo-Anderson open fracture classification. You can find out more about this classification system here: Gustilo Classification.
Low-Velocity Firearms[edit | edit source]
Low-velocity firearms, including small handguns and pistols, have a muzzle velocity of less than 1200 feet.[1] They tend to cause injuries that are similar to Gustilo-Anderson Type I and Type II injuries.[5]
- Type I[5][6]
- low energy
- wound size is less than one centimetre
- minimal soft tissue damage and fracture comminution
- wound is clean
- no neuromuscular injury
- Type II[5][6]
- moderate energy
- wound size is between 1 and 10 centimetres
- moderate soft tissue damage and fracture comminution
- moderate wound contamination
- no neuromuscular injury
Medium-Velocity Firearms[edit | edit source]
Medium-velocity firearms, including high-calibre handguns and shotguns, have a muzzle velocity between 1200-2000 feet per second.[1] However, wound severity depends on various factors, including the distance and projectile.[1][7]
Example: shotguns are medium-velocity firearms, but because of the "large total mass of their lead pellets can increase their kinetic energy dramatically. [...] Depending on the distance to the target and the size of pellets, shotguns can reflect the wounding potential of high-velocity firearms or multiple low-velocity weapons. [...] Very close proximity of shotgun to the target (< 2 m) results in not only the pellet projection, but also shell fragments and wadding."[8]
High-Velocity Firearms[edit | edit source]
High-velocity firearms, including military and hunting rifles, have a muzzle velocity greater than 2000 feet per second,[1] and they are associated with more substantial tissue damage.[7] They tend to cause Gustilo-Anderson Type III wounds.[5]
- Type III (A, B, or C)[5][6]
- high energy
- wound size is usually greater than 10 centimetres
- extensive soft tissue damage
- severe fracture comminution
- extensive wound contamination
- periosteal stripping present
- may require flap coverage (III B and III C)
- exposed fracture with arterial damage that requires repair may be present (III C)
Mechanism of Gunshot Injuries[edit | edit source]
- The projectile hits the body and transfers its kinetic energy and heat to the tissues
- This creates a permanent cavity approximately the size of the projectile's cross-sectional area
- The momentarily extreme pressure around the projectile's trajectory can create a vortex effect[1]
- This vortex effect causes the tissue around the projectile's trajectory to momentarily stretch out, forming a temporary cavity, before contracting back[1]
- The projectile may exit the body, usually creating a bigger exit point, remain in the body or change direction
- Sometimes the projectile fragments or explodes inside the body, causing further damage[1]
Effects of Gunshot Injuries[edit | edit source]
"While the tissues in the primary cavity sustain direct injury due to energy transfer, surrounding tissues within the temporary cavity sustain secondary injuries due to burns and extreme stretching."[1]
Gunshot wounds can have a range of effects, including diffuse soft tissue damage, muscle damage, nerve injury, vascular injury / haemorrhage, bone injury and severe pain.[9] These injuries are discussed in more detail below.
Soft-tissue Injury[edit | edit source]
The permanent cavity or temporary cavitation causes soft tissue damage:[9]
- tissues in the primary (permanent) cavity are injured by the projectile and extreme kinetic energy transfer[1]
- tissues in the temporary cavity are "destroyed by projectile compression and shearing that leaves a projectile trail"[9]
There may be partial or complete damage to the soft tissues, including ruptures, lacerations, internal burns and scarring in the later stages.[1]
Muscle Injury[edit | edit source]
"Skeletal muscle is suggested to be more sensitive to permanent cavitation, with temporary cavitation thought to induce less damage (unless the vasculature is disrupted) due to skeletal muscle’s inherent elasticity."[9]
Skeletal muscles can be affected by laceration, contusion or crush injury, denervation, haemorrhage, ischaemia, burns, and volumetric muscle loss. Primary trauma can be complicated by secondary trauma, including:[9]
- infection and sepsis as a result of contamination from the bullet or debris accumulated on clothing or the skin
- surgical debridement of damaged tissue
- excessive physical movement
Immobilisation and nutrient deficiency can lead to volumetric muscle loss after a gunshot injury.
Nerve Injury[edit | edit source]
Gunshot injuries can cause:[10]
- direct transection of the nerve
- indirect injury from thermal damage, shock waves, and laceration from fracture fragment displacement
- compression due to swelling or subacute scar formation
Therefore, gunshot-related injuries can cause axonotmesis, neuropraxia and neurotmesis.[11] Axonotmesis "describes the range of peripheral nerve injuries that are more severe than a minor insult, such as those resulting in neurapraxia, yet less severe than the transection of the nerve, as observed in neurotmesis."[12] Neuropraxia is the "focal segmental demyelination at the site of injury without disruption of axon continuity and its surrounding connective tissues."[13] Neurotmesis is a "complete transection of a peripheral nerve."[14]
The most frequently affected nerves in the upper extremities are the ulnar nerve and the brachial plexus.[10] Sheilds et al. also note that, in gunshot injuries, "vascular injury and fractures increase the risk of nerve injury".[10]
Vascular Injury / Haemorrhage[edit | edit source]
Blood vessels can be directly injured or affected by secondary circulatory compromise.[1] Vascular injury can lead to blood loss or haemorrhage (internal or external). A haemorrhagic area can form around irreversibly damaged tissue following gunshot injury. This extra vacation zone "is characterized by interstitial bleeding but the absence of macroscopically evident tissue destruction."[15]
Bone Injury[edit | edit source]
Gunshot injuries usually result in comminuted, displaced fractures:[1]
- caused by high-energy ballistic penetration
- a secondary effect of cavitation associated with the fluid properties of bone marrow
- associated with a high incidence of secondary complications, including infection and nonunion[16]
A drill-hole effect is often caused by low-energy injuries to porous, low-density / cancellous bone[8]:
- more common in the pelvis, distal femur, proximal humerus and spine[8]
- low-energy ballistic penetration
- affects the metaphyseal region of long bones
Unicortical fractures:
- can be due to "low-energy missile impact that creates only a tangential bone defect"[8]
Transverse or spiral fractures:
- can be caused by lower-energy gunshots to dense and highly-mineralised diaphyseal cortical bone
Gunshot injuries can result in secondary injuries (e.g. a fall), which can also result in fracture.[8][17]
Pain[edit | edit source]
- Patients with gunshot wounds in a combat setting have a high risk of chronic pain, "45% higher than the general population in civilian trauma patients"[18]
- 70% of individuals with gunshot injuries develop chronic pain[19]
- Kuchyn and Horoshko[18] found that individuals who were injured by gunshots in three or more areas had a higher percentage of chronic pain than those with injuries to one or two areas
- Complex regional pain syndrome (CRPS) can occur after traumatic events, including gunshot injuries[20]
Determinants of Injury Severity[edit | edit source]
- Projectile: velocity, mass, shape, calibre, material, yawing and impact distance:[9][1]
- mass / shape: as projectile diameter / length increase, more damage is likely
- velocity: as the velocity increases, the amount of kinetic energy dramatically increases, causing more harm
- impact distance: as projectiles travel longer distances, they lose more of their kinetic energy and cause less harm, whereas even smaller projectiles from close distances can cause extensive damage
- yaw is "the angle between the long axis of the bullet and its direction of flight."[21] As the distance increases, the projectile loses its stability and starts to yaw off. While this decreases the amount of kinetic energy transfer, it can increase the cross-sectional area, causing more damage[1]
- Type of tissue: density, elasticity, and thickness[9]
- high elasticity and low density equal less damage[21]
- skin has a high degree of elasticity and relatively low density
- lungs have a much lower density and absorb less energy
- bones are dense and absorb more energy
- The entry and exit points and trajectory within the body[1]
- if they are close to the nervous plexus, more severe damage can occur
- if they are close to main arteries or veins, the clinical presentation can be more complicated
- Projectile fragmentation
- more fragments = more than one trajectory within the body, which results in more severe internal issues to manage in the following days and months[1]
Potential Challenges and Secondary Complications of Gunshot Injuries[edit | edit source]
The management of the secondary complications related to the gunshot injury is complex. Early intervention and in-depth knowledge are required to maximise rehabilitation outcomes.
Some secondary complications of gunshot injuries are listed below:[1]
- joint contractures can develop as a result of periods of immobilisation after comminuted and complex open fractures that require external / internal fixation
- myofascial, chronic, or neuropathic pain can develop due to internal scarring, internal burns, wound or bone infection
- peripheral nerve injuries that are initially undetected due to heterogeneity and the conditions on the field may require referral to a specialist
- deep vein thrombosis or different types of embolism
- complex regional pain syndrome (causalgia) known as military pain syndrome - "tends to affect combat soldiers after they sustain wartime injuries from blasts and gunshots"[22]
- central sensitisation
- mental health issues, including post-traumatic stress disorder, anxiety or depression, which tend to worsen over time with long-term declines in mental health status[23]
Skills and Knowledge Required to Treat Gunshot Injuries[edit | edit source]
It is recommended that rehabilitation professionals treating gunshot injuries have a solid understanding of the following topics:[1]
- neuroanatomy
- to perform a neurological examination
- to plan treatment
- to recognise signs and symptoms that warrant referral to speciality services
- pain neuroscience
- to provide pain education to help manage chronic / persistent pain
- clinical reasoning
- to manage complex cases
- to participate in / lead a multidisciplinary team
- manual skills
- to help manage joint contractures, internal scarring, and neurogenic compromise
Resources[edit | edit source]
References[edit | edit source]
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 Altunbezel Z. Introduction to Gunshot Injury Rehabilitation Course. Plus, 2024.
- ↑ 2.0 2.1 2.2 Wild H, Stewart BT, LeBoa C, Stave CD, Wren SM. Epidemiology of Injuries Sustained by Civilians and Local Combatants in Contemporary Armed Conflict: An Appeal for a Shared Trauma Registry Among Humanitarian Actors. World J Surg. 2020 Jun;44(6):1863-1873.
- ↑ Stewart S, Tunstall C, Stevenson T. Gunshot wounds in civilian practice: a review of epidemiology, pathophysiology and management. Orthopaedics and Trauma 2023; 37(4):216-221.
- ↑ Menezes JM, Batra K, Zhitny VP. A nationwide analysis of gunshot wounds of the head and neck: morbidity, mortality, and cost. J Craniofac Surg. 2023 Sep 1;34(6):1655-60.
- ↑ 5.0 5.1 5.2 5.3 5.4 Gustilo Classification. Available from https://www.orthobullets.com/trauma/1003/gustilo-classification [last access 14.04.2024]
- ↑ 6.0 6.1 6.2 Kim PH, Leopold SS. In brief: Gustilo-Anderson classification. [corrected]. Clin Orthop Relat Res. 2012 Nov;470(11):3270-4. doi: 10.1007/s11999-012-2376-6. Epub 2012 May 9. Erratum in: Clin Orthop Relat Res. 2012 Dec;470(12):3624. Erratum in: Clin Orthop Relat Res. 2019 Oct;477(10):2388.
- ↑ 7.0 7.1 Baum GR, Baum JT, Hayward D, MacKay BJ. Gunshot Wounds: Ballistics, Pathology, and Treatment Recommendations, with a Focus on Retained Bullets. Orthop Res Rev. 2022 Sep 5;14:293-317.
- ↑ 8.0 8.1 8.2 8.3 8.4 Gugala Z, Lindsey RW. Classification of Gunshot Injuries in Civilians. Clinical Orthopaedics and Related Research 2003;408():p 65-81.
- ↑ 9.0 9.1 9.2 9.3 9.4 9.5 9.6 Moriscot A, Miyabara EH, Langeani B, Belli A, Egginton S, Bowen TS. Firearms-related skeletal muscle trauma: pathophysiology and novel approaches for regeneration. NPJ Regen Med. 2021 Mar 26;6(1):17.
- ↑ 10.0 10.1 10.2 Shields LBE, Iyer VG, Zhang YP, Shields CB. Gunshot-related nerve injuries of the upper extremities: clinical, electromyographic, and ultrasound features in 22 patients. Front Neurol. 2024 Jan 11;14:1333763.
- ↑ Straszewski AJ, Schultz K, Dickherber JL, Dahm JS, Wolf JM, Strelzow JA. Gunshot-Related Upper Extremity Nerve Injuries at a Level 1 Trauma Center. J Hand Surg Am. 2022 Jan;47(1):88.e1-88.e6.
- ↑ Chaney B, Nadi M. Axonotmesis. 2023 Sep 4. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan–.
- ↑ Biso GMNR, Munakomi S. Neuroanatomy, Neurapraxia. [Updated 2022 Oct 24]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from https://www.ncbi.nlm.nih.gov/books/NBK557746/ [last access 16.04.2024]
- ↑ Matos Cruz AJ, De Jesus O. Neurotmesis. [Updated 2023 Aug 23]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK559108/
- ↑ Stefanopoulos PK, Hadjigeorgiou GF, Filippakis K, Gyftokostas D. Gunshot wounds: A review of ballistics related to penetrating trauma. Journal of Acute Disease 2014;3(3):178-185.
- ↑ 16.0 16.1 16.2 Yeganeh A, Amiri S, Otoukesh B, Moghtadaei M, Sarreshtedari S, Daneshmand S, Mohseni P. Characteristic Features and Outcomes of Open Gunshot Fractures of Long-bones with Gustilo Grade 3: A Retrospective Study. Arch Bone Jt Surg. 2022 May;10(5):453-458.
- ↑ Smith HW, Wheatley KK Jr. Biomechanics of femur fractures secondary to gunshot wounds. J Trauma. 1984 Nov;24(11):970-7.
- ↑ 18.0 18.1 Kuchyn I, Horoshko V. Chronic pain in patients with gunshot wounds. BMC Anesthesiol. 2023 Feb 7;23(1):47.
- ↑ Horoshko V. Value of the number of injured anatomical parts of the body and surgeries for pain chronicity in patients with gunshot wounds and blast injuries. Emergency Medicine 2023;19(3):141–143.
- ↑ Tieppo Francio V, Barndt B, Towery C, Allen T, Davani S. Complex regional pain syndrome type II arising from a gunshot wound (GSW) associated with infective endocarditis and aortic valve replacement. BMJ Case Rep. 2018 Oct 16;2018:bcr2018224702.
- ↑ 21.0 21.1 Gunshot Wounds: Management and Myths (2012). Available from https://www.reliasmedia.com/articles/76797-gunshot-wounds-management-and-myths [last access 16.04.2024]
- ↑ Nelson CN, Glauser G, Kessler RA, Jack MM. Causalgia: a military pain syndrome. Neurosurgical Focus 2022;53(3): E9.
- ↑ Greenspan AI, Kellermann AL. Physical and psychological outcomes 8 months after serious gunshot injury. J Trauma. 2002 Oct;53(4):709-16.