Odd Job's Gunshot Thread

[Odd Job]

After various threads along the lines of "This guy was hit x times with y ammo of z calibre and he still didn't die" I have decided to tell you all what my perspective is on gunshot wounds and shot placement. To begin with let's go over what we are told by all the experts as regards neutralising a threat by means of gunfire:

1) It is accepted that there are certain 'critical' organs and structures within the human body which, if significantly damaged, will lead to the neutralisation of that individual's ability to pose a threat.
2) It is also accepted that if we intend to damage those structures we must deliver a projectile that has the ability to penetrate deeply enough into the target to reach and damage those critical organs and structures.
3) Lastly we must have some exterior landmark to aim at, which will correspond to the position of the critical organ that we are aiming to damage.

And these three points are very difficult to satisfy in real-world shootings because of the variables involved.

To illustrate this, let us pretend that every bad guy we ever encounter will always stand with his arms out sideways (as in Figure 1) and that there is a critical rectangular plate of known dimensions within his chest (as in Figure 2, 3 and 4). Let us also pretend that any bullet that can pass through that plate so that it damages any two parallel surfaces of the plate, will result in an instant incapacitation of that man.











If that is the case, then an ideal shot will be in the center of the chest, through the sternum and through the plate, as indicated by the red line trajectories in Figure 5 and 6:







Continued...

[Odd Job]

Of course, we cannot aim directly at that plate at the time of the shooting because we do not have X-ray vision, so we choose an overlying surface landmark instead. If we retain the red trajectory in Figure 6 but this time only mark where it enters the skin, we can make a blue aiming point on the man's chest as in Figure 7:





This blue circle seems to be the ideal aiming point if we want to hit that critical red area within the chest. Okay, so let's assume for now that everybody here can satisfy the following requirements:

1) Hit that blue circle ALL the time, 100% accuracy.
2) Deliver a projectile that cannot be deflected, fragmented or otherwise impeded by the target's tissues. In other words, this will be a projectile that travels in a straight line like a laser beam, no matter what it hits.
3) The projectile has sufficient energy to penetrate the man's chest and perforate the critical red area.

Even if the above points could be satisfied, we would still have variables to do with the position of the shooter relative to the position of the target. There are numerous combinations of these positions whereby even if the above three points are satisfied, the projectile fails to even touch the red critical area. Examples can be seen in Figures 8 to 11:



Note that in the above trajectories the blue circle has been hit but not the red area within the chest.
Now we must add another variable: the fact that the bad guy doesn't want to stand there with his arms out sideways showing you his chest so you can pick a spot to hit. Have a look at these poses and try to imagine where that blue circle is in all of them. In those cases where you automatically dismiss the blue circle as a valid aiming point, try to work out where you would aim to hit the red area within the target:



This is why we get told to aim for center of mass (COM). The reason being that we are likely to hit something of some 'value' even if we don't hit the 'magic red area.' So therefore in the following figures, the COM would be where I have shaded them:





Note the problem of the target's profile and build. A fat guy or a big-busted woman when standing sideways may appear to be offering quite a large COM, but in reality the critical area available to be struck is less than would be available if they stood facing the shooter. This is how you get COM hits that 'go right through the target' but do not have the required effect, and that's when we get blame put on the weapon/calibre/ammunition type. You only have to spend some time in the emergency room of a large trauma center to see perforating gunshot injuries that have failed to kill or even seriously injure the victim.

Note also that so far we have not even touched on the subject of projectile deflection or fragmentation within the clothing or tissues of the target. A projectile that may have been traveling straight towards the critical area as in Figure 7, may not reach the critical area if it is deflected by the sternum or an anterior rib end. Another thing to remember is that there is no such thing as a nice geometric 'red critical area' as I have drawn here. That was just a convenient way for me to demonstrate the trajectory variables involved. There are substantial variables in the size and position of vital structures such as the heart and great vessels within a person's chest. Further surface variables exist such as muscle content, fat, clothes, bone mineralisation etc. This means that you cannot guarantee that a bad guy will go down even if you are fortunate or skilled enough to place that shot exactly where you intend it to go. Even head shots are not a guarantee to instantly incapacitate somebody.

[rmagill]

Overall, this seems decent (and that a lot of work went into hit). However, you seem to negate the idea of a head shot. For some of these (particularly pic. 14), it seems to be the best way to as quickly as possible neutralize the target would be with a head shot (between eyes, down to the nose), which is not in the "red box", but is even more effective. While it may be "smaller" and "harder to hit, espcecially while moving around", in some cases, this may actually be the easiest way to neutralize the target.

Personally, I would aim a little high of the blue circle (sometimes my shots drop) and, if this is not an option, go for a head shot (leathal force, as any gunshot is, is leathal force and is regardless of the actual outcome. I.e. there is no legal difference (in PA) between shooting comeone COM and in the head if shooting would be justified).

But this is just my .02

[BlueTrain]

Wow, what a post! Among other things, it tends to make you think about exactly what you are trying to do, which is to shoot another human being, presumably with the intent to kill them. One cannot assume otherwise.

There are some interesting parallels with being stabbed with a knife or sword and there have also been some well written studies about that. The chief problem, which also applies to being shot, is that people often refuse to conform to our expectations with regards to injury. All the same, it is an easy matter to inflict a fatal wound. The problem is the difficulty of producing a quickly disabling wound. There are plenty of instances to prove both points and they are regularly reported in the paper, though not necessarily accurately.

Some of statements in the first post suggest that a full metal jacket would be the preferred load and in some instances it undoubtedly would be. There are plenty of people here who would agree the a .45 auto with a full metal jacket would take care of any problem they would care to tackle with a pistol, so they see no problem. Of course, at the same time, the problem is nothing like so simple as the illustrations suggest and besides, the target really goes all the way to the ground. And people don't always wear form fitting garments.

I'd like to also suggest a couple of things about headshots. It may be true that the skull is difficult to penetrate and a bullet will likely be deflected. But it is also true that a hit to the top of the head will almost certainly cause the person to drop like a rock. It is unlikely to be fatal even though it will be an awful looking wound and the individual is very likely to quickly recover enough to get up again almost right away. Nonetheless, such a hit is likely to cause such a reaction. And a person's head is almost always in view even when nothing else is.

[18DAI]

Great info/graphics, thanks. One question though, why would anyone want to shoot a big busted woman? Regards 18DAI.

[Odd Job]

@ rmagill and Blue Train

A head shot might be nice, but it is a small area. The other problem is that if you hit the guy anywhere in the face, there is a greater chance for a deflection away from the skull vault itself. One of our trauma nurses sustained a gunshot wound just under the eye and the bullet was deflected downwards by the inferior orbital rim through her mouth and into her neck. She lost an eye but her brain was not harmed. In a similar vein I have seen many patients come into the hospital with gunshot wounds to the head and many of those have not suffered a loss of consciousness at all. Many of those have been tangential to the bone. If you could guarantee to hit the head all the time, and in such a manner as to cause an undeflected trajectory involving the brain, then I say yes that is preferable to a chest shot. But it is a big 'if' in my book.

[rmagill]

Odd Job,

A head shot is not my prefered aiming point. However, if someone is threatening immediate severe bodily harm or death, they need to be stopped. If a shot "in the box" is not available, the only other alternative that I know of that has a chance of instantly stopping them is a head shot.

I know that the odds of a successful incapacitation is low, but it would be the only remaining shot that has a chance of immediately incapacitating them. Again, in picture 14, the shootable area below the suspect's arms is roughly the same as the shootable area of his head. So the question becomes, which will stop him quicker? Shots to non-vital organs (the arguement of "Ow, you shot me, I will now stop" aside) will not instantly stop him. However, a shot to the head has a much higher chance of immediately stopping him than would a shot to the lower torso.

As for odds of hitting the brain/CNS, that is where training comes into play. We should all practice enough to be a good enough shot to shoot him every time in the soft spots in the head (eyes/nose) that would allow a bullet to disrupt the CNS the easiest. Granted, I am not there yet, but that is why we practice.

A head shot is not my first choice. As I said, my first choice is to shoot him in "the box". However, when this is not possible and I need to stop the threat immediately, I will take the possability of an instant stop over the unlikelihood of a one-shot-stop to a non-vital organ. But this is my .02 cents. Feel free to disagree.

[Boondoggie]

This is an awesome presentation, great job.

[Odd Job]

@ All

Thanks!!
I use the same style when I do talks/presentations. I am one of these dudes who LOVES pictures.

[BlueTrain]

Actually, this presentation (the graphics) rather transforms an academic discussion of shootings into something gruesome, but those are the facts of gunshots.

My mention of headshots was intended to highlight certain points. I did not intend to suggest the head was not difficult to hit but rather that the head will often be the most exposed body part and that is one reason soldiers wear armor first on their head. It is also the part you are most likely to focus on (unless it is a big busted woman!!) when looking at another person and it is possible that may have an unconscious effect on your aim.

Likewise, I was only suggesting that a hit to the head will very likely put the person down immediately, if it does anything, but even so, such a wound, if not immediately fatal, will possibly only cause a momentary incapacitation. Generally speaking, it would be similar to reactions in a boxing match. Not much to count on but better than nothing.

The reaction of an individual when shot will still be difficult to predict since the circumstances will be so varied.

Another thought that just occurred to me is that in military training, the head is sometimes taught to be the aiming point for certain ranges, as are other points up and down on the torso, but this has nothing to do with pistol shooting.

[dfaugh]

Mozambique---2 to the chest, SLIGHT PAUSE, one to the head. many of my friends in LE are now being taught this. Negates inability to make "clean" COM hits, or body armor. COM is first choice, as its a bigger target, but head shot will usually be disabling, if not fatal.

[Odd Job]

@ All

The point I am keen on making is that no matter where you intend to place your shot, even if you can do so with millimetric precision, there is no guarantee that the surface placement will result in the deep structures being hit as intended. This applies to head shots too. Have a look at this real life shooting (from my research files, Case no 35):

WARNING: This photograph is not for the faint of heart
http://i55.photobucket.com/albums/g1...e35APPhoto.jpg

How do you like that shot placement? Anything wrong with that? No. Yet...the bullet was deflected by the frontal bone and it followed an inferior path through the maxillary sinus on the left, through the upper molars (which were smashed) and then into the oral cavity and then into the tissues lateral to the mandible. I found one lead fragment in his stomach too (ingested), when he went for CT of the head (I added a scout view of his stomach). His brain was untouched and he was a sole maxillo-facial concern.

So I would summarise by saying that deflections are not a rare occurence, they are quite common and I have many cases that demonstrate this (not just involving the head and chest, and not all involving bone strikes).

[Odd Job]

@ BluesMan

Oops, sorry, I didn't think that picture was so bad.
I'll link wound photographs in future.

[smiling cobra]

most excellent...I was taught mozambique...or triple tap years ago as a state LEO..Odd job that was a great presentation...thanks COBRA>>>Semper Fi

[Odd Job]

I must warn you that all the linked images are graphic.

I am seeing varied and confusing terminology when discussing the behaviour of a projectile when interacting with a target on this board. I thought I would describe the terminology I use as applies to gunshot wounds.

There are four possible outcomes when a projectile is fired at a person:

1) It can miss.
2) It can graze the person.
3) It can go into the person and not come out. The proper term for this is a penetrating injury.
4) It can go into the person and some or all of the original projectile can come out. The proper term for this is a perforating injury.

I am not concerned with number (1) above, I am only concerned with hits of some description. Likewise I am not concerned with intermediate targets, I am only concerned with the type of injury the projectile causes from the moment it hits the target.

Vincent Di Maio says that there are 4 types of gunshot wounds:

1) Graze
2) Tangential
3) Penetrating
4) Perforating

His description of a graze injury is the same as my description of a tangential injury. His description of a tangential injury is one where the skin is ripped in a ragged fashion and there is potential for underlying subcutaneous damage. The examples he offers in his book "Gunshot Wounds" are all due to high velocity projectiles from centerfire rifles. I would rather call those injuries perforating injuries because it is my opinion that those projectiles have breached the skin and that the rupture of the skin along the bullet track is not due to the direct passage of the projectile. The ragged nature of the breaches supports my observation (the tears look like lightning strikes).
Anyway the point I am making here is that I have a different view from Di Maio and I only describe three types of gunshot wounds:

1) Tangential
2) Penetrating
3) Perforating

Di Maio and I have the same description of what a penetrating and perforating wound is. I will provide graphics to demonstrate the 3 types as I describe them. Figure A is a tangential trajectory, Figure B is a penetrating trajectory and Figure C is a perforating trajectory.







The key features of a tangential gunshot injury are as follows:

1) It is a 'graze.'
2) The wound can be visually inspected. There is no damage that is not directly accessible by the health care worker.
3) No projectiles or fragments thereof are retained in the wound.
4) This is the only gunshot wound that does not merit being X-rayed. The reason it does not have to be X-rayed is because the clinician's visual inspection provides all the information he or she needs to assess the severity of the wound.
5) Generally the patient does not require hospitalisation. The only detrimental effects to look out for in these cases are those relating to infection and also those related to psychological stress on the victim.

Here is a typical tangential wound (Vincent Di Maio calls this a graze wound).

http://i55.photobucket.com/albums/g1...Tangential.jpg

The key features of a penetrating gunshot injury are as follows:

1) All of the original components of the projectile that were incident to the skin, are retained in the body.
2) Whether the projectile fragments or deforms is irrelevant to the classification of this injury as 'penetrating.'
3) If the projectile or fragments thereof are propelled through the body by natural means and are subsequently expelled this remains a penetrating injury. There are many cases in the literature where this has happened. A typical example would be a projectile fragment that enters the urinary system and is subsequently expelled in the urine.
4) All penetrating gunshot injuries must be X-rayed because the clinician cannot visually inspect the wound track and therefore cannot give a 100% guarantee that all projectiles or fragments thereof have been accounted for.

Here is a typical penetrating gunshot wound (note that technically if you were dead certain that no other skin breaches were present, you could confidently call this an entrance wound):

http://i55.photobucket.com/albums/g1...enetrating.jpg

The key features of a perforating gunshot injury are:

1) All or part of the projectile that was incident to the skin travels subcutaneously and makes an exit from the body.
2) It does not matter whether the whole projectile exits or only a piece of the core, or only a piece of insert or only a piece of jacketing: this is still a perforating gunshot wound.
3) If a projectile breaks into two pieces and only one piece makes an exit, this is still a perforating wound. This classification is not affected by projectile fragments remaining in the body.
4) All perforating gunshot wounds must be X-rayed.

Here is a perforating gunshot injury:

http://i55.photobucket.com/albums/g1...erforating.jpg

Now there are several things I want to point out here. Firstly there are pitfalls surrounding the classification of a wound as perforating. The most problematic of these pitfalls is the tendency of some ER clinicians to count skin breaches and attempt to classify the wound in that manner. For example they will count two holes and assume that this is a perforating injury. However those two holes could easily be two entrance wounds from two penetrating injuries.
The next pitfall is the tendency of some ER clinicians to expect exit wounds to be larger than entrance wounds, and indeed, to classify wounds as being those of entrance or exit based purely on the size of the wounds or a general 'impression' of the wounds. There is adequate literature to indicate that clinicians generally do not accurately describe wounds of entrance and exit. I put this down to lack of experience or forensic training or lack of means and time to examine these wounds and arrive at a proper determination of whether these are entrance or exit wounds. My experience in a very busy trauma unit in Johannesburg leads me to make the following recommendations to ER staff:

1) Do not, in any written or verbal communication or documentation, make a statement to the effect that a particular wound is an entrance or exit wound, unless supplementary evidence not related to the appearance of the skin breaches themselves is at hand. In simple terms, don't declare it unless you have other proof such as X-ray imaging (radiology can determine which wound is the entrance and which one is the exit in some cases), or clothing evidence (a failed exit through the fabric means the corresponding skin breach is an exit wound in most cases).
2) Size doesn't matter. Granted, in most perforating injuries where the bullet has remained intact the exit wound will be larger because the bullet may have yawed or expanded prior to exit. However, don't forget what I said about perforating injuries: you need only have a portion of the original projectile making an exit in order for this to be a perforating injury. You can't be sure of which components have exited the body without having good knowledge of what the radiological appearances of a particular projectile are, coupled with knowledge of what projectile is involved in the case at hand.
3) The patient's recollection of events may not be accurate. There may be a nefarious rationale behind this. Asking how many shots were fired may not be helpful, depending on the circumstances of the shooting.

As I said previously you have less chance to make a mistake by finding a single skin breach and calling that the entrance wound as opposed to assuming that multiple breaches are due to a perforating injury.

When discussing other targets such as gel blocks, car doors, furniture etc I would use the same terminology. If a bullet penetrates a car door it means it went in one side and did not come out the other. If it went through the car door, then it perforated the car door. And then you have the added factor of tangential shots producing ricochets, but that is a subject for another thread.
I'm here mainly to talk meat, not metal

[CDH]

Based on your first post, you seem to be concentrating on the heart as the only organ that will put an immediate stop to an attacker (the little square in red).

And you also intimate by your subsequent post that you are in some kind of position as a coroner or some profession that allows you to take bodies apart.
I can't make such claims, but I have looked at the issue of a preferred one-shot stop hit, and I think you are putting too much emphasis on such a small target.

There is a major nerve bundle that runs from the brain straight down the spine. Any hit on that bundle will place enough shock to the nervous system that a person hit in that way would drop immediately because those nerves involve all motor abilities in the rest of the body.

So my .02 is that any shot placed at the sternum and up to the head will stop an attack immediately. Of course, that's assuming a straight on placement, but if you aim (and hit) at center of chest (basically what you said), you are going to stop the attack.
I think that the standard teaching to shoot "center of mass" is that it doesn't matter how the attacker is facing you, you will still hit vital parts because center of mass is not "center of chest", but "center of mass of the target" which could be in many places other than center of chest depending on how the attacker is facing you.

I just think that there's a lot more in the chest cavity that can be hit that will put an attacker down, including a wound that punctures the lung even though it's not in the nerve bundle.

I don't disagree with your assessments, I just think that hitting "center of mass" is a lot easier to concentrate on while under stress where you fear for your life than trying to think "Let's see now, he just turned 15 degrees to the left so I have to adjust my aim 2.7 inches to the left and up about an inch."

Once the action starts, it has been shown that there is very little thinking going on, so again, shooting for "center of mass" (as presented to you) shortcuts a lot of what you said.

Carter

[Odd Job]

@ CDH

In my first post I made it clear that I was using that illustrative red plate in the chest as an example:

To illustrate this, let us pretend that every bad guy we ever encounter will always stand with his arms out sideways (as in Figure 1) and that there is a critical rectangular plate of known dimensions within his chest (as in Figure 2, 3 and 4). Let us also pretend that any bullet that can pass through that plate so that it damages any two parallel surfaces of the plate, will result in an instant incapacitation of that man.

I am not a coroner or even a doctor. I am a radiographer. I have certain dealings and research to do with gunshot wounds and Johannesburg is the place where I got my experience.

Generally my advice corresponds to the latter part of your post.

[Odd Job]

@ CDH

So my .02 is that any shot placed at the sternum and up to the head will stop an attack immediately.

Well it is a very small target, if you intend to cause neurological incapacitation at that level. You have to disprupt the spinal cord. If you look at a CT scan of a neck and see how small the area is in the axial plane, you will realise it is going to be very difficult to hit intentionally.

Edit: here is a CT slice through the neck at the level of C3-C4. Basically for those not in the know, it is a type of cross-sectional medical imaging that uses multiple X-ray projections to compute a section of anatomy in any given plane. In this case the plane is axial (what you would see if you fed the guy's neck through a bacon-slicer). The white arch at the top is the jaw, so you are looking at this as if the guy is lying on his back.
I have outlined in red where the spinal cord sits and I have been a little generous in describing its size. But overall I am sure you will agree that the spinal cord is quite small. Of course, you could get lucky and hit the guy's spine (the light grey thing around the red dot) so that pieces of bone are projected backwards into the spinal canal, and those pieces may sever or damage the cord. But I wouldn't go for that shot myself.

[bdarin]

What about being so scared that you empty the weapon into the person? Seems that at least one of those (6,8,9,14) shots will do the trick, even with crappy lead wadcutter bullets. Course, all I know of gunshot wounds I learned right here (nice work, Oddjob), so I'm far from being an expert. I guess I'm looking more at the quantity of lead rather than the quality, since we're probably in a panic situation here, especially if it's your first time having to do this. OK?

[Odd Job]

@ bdarin

Agreed, I don't know what will happen. I know what I should do, as I sit here nice and comfortable at my keyboard out of harm's way in London. But whether I do it if the time comes, I cannot predict. I have not been in a gunfight and I hope I never will be in one.

[Odd Job]

The question of spinal CNS incapacitation came up in another thread. There is some confusion about what spinal incapacitation is and where it originates from. The first thing to realise is that the spinal column is a bony structure, which, if damaged, need not result in damage to the spinal cord which is the thing we are really interested in when we speak of CNS incapacitation outside of the brain. It is the spinal cord that transmits 'nerve instructions' between the brain and the body and this has nothing to do with the vertebrae themselves.
I have rendered some simple diagrams to illustrate where the spinal cord is in relation to the spine. In the following image I have produced three views of the spine and added a red tube where the spinal cord sits in the spinal canal. The spinal canal is a space provided within the posterior elements of the spinal column.



When discussing injuries of the spine, we speak about the vertebral level at which the injury occurs. It is therefore important to know how many vertebrae there are, and what the regions are. We have three regions: cervical (the neck), thoracic (the thorax or chest area) and the lumbar (your lower back). There are 7 cervical vertebrae, 12 thoracic vertebrae and 5 lumbar vertebrae. Between the vertebral bodies you have discs. You can think of these as a kind of rubber shock absorber. These do not show up on plain radiographs ('X-rays').
I will not discuss variants here (such as people who have 6 lumbar vertebrae). We will go with the standard 7,12,5 configuration. The spinal regions are abbreviated C, T and L.
So we have abbreviations for each vertebra and therefore each possible level that we want to discuss. For example we know that the spinal cord ends at the level of the second lumbar vertebra so that is abbreviated 'L2.' Beyond L2 there are nerves that branch out from the spine and go down to the lower body amongst other places.

Here is a representation of T8 (which could possibly be hit if you are shooting COM whether from the front or the side or behind). I have left the whole cord in the render so you can see how it runs behind the vertebral body:



And here is another render of the thoracic spine. On the left you see it intact, and on the right it is in longitudinal section. Note where that cord sits, it is the key to this discussion:



Okay, we now know where the cord sits and how many vertebrae there are, and what the basic 'architecture' of the spinal column is. But there is more to consider, especially when you want to know about spinal incapacitation. Now I will tell you this in basic terms (which is just as well because I do not profess to be an expert on spines, neurology or orthopaedics as pertains to spines. I am telling you this as a radiographer). These are the salient points for consideration in this discussion:

1) Nerves branch out from the spinal cord at various levels, to 'supply' the various parts of the body.
2) There are sensory and motor components of these nerves, and indeed of the cord itself. It is possible to have minor damage to the cord or the nerves that branch out from it such that only the motor or only the sensory component is damaged (you can move but can't feel, or you can feel but can't move). This is more common with stab injuries but is possible with gunshots too.
3) If you cut the cord completely (called a transection) then all nerves below that level and all parts of the cord below that level lose sensory and motor components. All the regions of the body that would have had a nerve 'supply' will now be paralysed.
4) The higher the level of damage, the more parts of the body will be paralysed. For example damage to the cord at C4 is far worse than damage to the cord at L1, because in the former case you lose the use of your arms and legs whilst in the latter case you lose the use of your legs only.

Now let us see what is required to incapacitate a person by spinal cord damage (which falls within the broad category of CNS damage but excludes the brain itself):

1) If you want to deny the individual the use of his arms, you have to damage the spinal cord at the level of C5 or higher. This is a neck shot. You cannot accomplish this by firing COM (assuming there is no deflection up into the neck). So if the guy has a gun and you shoot COM, he isn't going to drop it because of CNS damage.
2) If you want to deny the individual the use of his legs, you have to damage the spinal cord at the level of L2 or higher. The guy can't run but maybe he can still shoot you if he is armed.
3) No matter what level this damage occurs at, the damage must be sufficient to disrupt, impinge or otherwise impair the spinal cord completely. This need not happen by direct contact with the projectile: it could happen as a result of secondary bone projectiles derived from damage to the bony spine itself.
4) When shooting an individual from the front you will either have to shoot through a vertebral body or an intervertebral disc, or fracture the vertebral body so that bone fragments are projected backwards into the spinal canal in sufficient quantity and sufficient depth to disrupt the spinal cord.
5) When shooting an individual from the back or side, there is less bony protection for the cord. Nonetheless your bullet may have to go through posterior elements in order to hit the cord. There is less bone available to project into the spinal canal.
6) There have been cases where the cord has been damaged without any damage to the bony spine. In gunshot cases that I have seen this damage has resulted in a sensory or motor deficit, although it is obvious from the structure of the spine and the 'windows' onto the spinal cord (neural foramena and space between the spinous processes posteriorly) that the cord can be accessed and transected without damage being caused to the bone.

Here is a nice link where you can see what damage and type of paralysis can be expected from damage to the spinal cord at various levels:

http://www.apparelyzed.com/support/f...nality/c5.html

I will shortly add two cases from my files to demonstrate two different sorts of damage to the spinal cord and spinal canal area as a result of gunshots.

[Odd Job]

Case number 1 (gunshot spine)

A young male was shot in the left flank and arrived at the hospital fully conscious but with localised tenderness over the lumbar spine and decreased sensation in one leg (I did not document which leg it was at the time).
These are his initial radiographs:



It was immediately apparent that he had a nasty fracture of L4 (red arrows). The entrance wound was marked with a paperclip (yellow arrow, but collimated off AP view). A largely intact FMJ was seen behind the iliac blade on the right (the hip bone). The radiological trajectory of this bullet was therefore from left flank, through the abdomen, through L4 and through the iliac blade on the right. That is a significant penetration.

Whenever the spine is fractured, a CT scan is ordered (some of you may know these as CAT scans) in order to plot the fractures in more detail. Here are nine sequential CT slices through the vertebra that was damaged (L4):



In the first slice (no 1) I have superimposed a red circle where the spinal canal is. Now take note that this injury was at the level of L4 so there is no spinal cord there, but there will be nerve roots in the vicinity. The thing that I want to show you here is the mechanism of damage and encroachment on the spinal canal. If you look at slice 3, I have indicated one of the many fractures of this vertebra with a green arrow. All those grey lines are fractures (breaks in the bone, caused by the bullet). In slice 4 I have arrowed a small projectile fragment (yellow arrow). This is a small piece of lead, probably from the base of the bullet, that has been deposited in the vertebra as the bullet passed through. In slices 6,7 and 8 I have arrowed pieces of the vertebra that have been projected into the spinal canal by the bullet (blue arrows). You can see how the spinal canal is encroached by those bone fragments (compare to slice 1).
Here is a sagittal reconstruction (a virtual longitudinal section) through the damaged vertebra. You can clearly see how a large chunk of L4 bone has gone posteriorly into the spinal canal:



If this injury had been higher up, you can see how the spinal cord would be damaged by the bone of the vertebra even though the bullet probably did not go into the spinal canal.

Note that just because the bullet fractures the spine, doesn't mean that there will be damage to the spinal cord or projection of bone fragments into the spinal canal. I have seen many cases where only the vertebral body is damaged and the spinal canal is not breached by bone or bullet. Like many other encounters between bullet and bone, the results can be unpredictable. Would a JHP have performed the same? It is impossible to say. Would a repeat shooting under laboratory conditions with the same gun and ammunition produce the same result? Impossible to say. Such is the real-life variation of gunshot wounds, especially when they involve bone.

Case 2 to follow...

[JohnKSa]

I appreciate the thought and effort that has gone into this thread. Very interesting and informative.

[Odd Job]

Case number 2 (gunshot spine)

This one is a bit complicated.

A young man sustained a penetrating gunshot wound to the back. On arrival he had localised pain in the lumbar spine, paralysis of one leg and decreased motor and sensation in the other (I did not note at the time which leg was paralysed). These are his initial radiographs:



The bullet entered posteriorly and centrally (yellow arrow). It then caused a fracture of L3 (red arrow) and suffered significant fragmentation, depositing multiple daughter fragments in the wound. The parent fragment (blue arrow) came to rest in front of the spine at the level of L2.
This bullet is obviously jacketed. You can appreciate the difference in density especially on the lateral view (side view) of the spine. It is possible that this was a JHP, but it could also be an FMJ that fragmented upon encountering the spine.
Of course with a situation like this, you have to CT scan the guy:



Now you can appreciate the amount of damage that was done. Again I have indicated some of the many fractures with green arrows. In this case most of the damage to the spinal canal was done by the projectile or daughter fragments of the projectile. I have indicated with orange arrows several examples (not all) where fragments of the projectile are lodged in the spinal canal. Other projectile fragments are indicated with yellow arrows. Note the projectile fragments lodged in the vertebral body in slices 12, 13 and 14. Pieces of the bullet have also been lodged in the region of the fractured posterior elements (best seen on slices 14 and 15). The parent projectile can be seen in the top left corner of slices 3-10. This corresponds to the right hand side of the patient's anatomy. Those streaks that you see emanating from the projectile fragments are a type of imaging artefact associated with metals and other dense materials. It basically results from a failure of the X-ray beam to penetrate the item and therefore the computer software renders the incorrect density (usually a dark or light streak) for the anatomy in the path between the bullet and the CT detector. Similarly if you look at the parent projectile in slices 6 and 7, it appears to have a black hollow. This is a false representation. That could be a solid piece of lead. This happens because the X-ray beam cannot penetrate that large piece of lead and the CT detector therefore gets no data for that region.

This injury is worse than the previous case for the following reasons:

1) The projectile has passed through the spinal canal and deposited projectile fragments within the spinal canal at multiple levels. Bone fragments from the factured posterior elements are also present in the canal.
2) There are more fractures, involving the body and posterior elements of L3, but also the vertebra above is fractured (L2).
3) The possibility exists to damage the spinal cord at the level of L2, and this may very well have happened. It is not possible to determine in all cases where a projectile has passed, but the indications in this case that the spinal cord may have been damaged are compelling, especially when you see the projectile fragment lodged in the canal at the level of L2 (see slice 3).

In both these cases I have not discussed vascular or abdominal organ damage, because the subject here is CNS incapacitation from spinal gunshot wounds. You should note that other factors come into play, depending on the level at which the spine is damaged. There are major vessels running alongside the spine such as the abdominal and thoracic aorta and the inferior vena cava. In the cervical spine you also have the vertebral arteries that pass through two foramena (holes) in the posterior elements on their way to the brain. A gunshot injury to the cervical spine therefore carries the risk of a vascular injury even though the aorta and superior vena cava are out of harm's way. I have one such case in my file where a man sustained a gunshot injury to the neck, resulting in a fractured vertebra and damage to one of the vertebral arteries, but the spinal cord was untouched.

Here is a well illustrated overview of spinal anatomy:

http://www.fleshandbones.com/readingroom/pdf/275.pdf

Edit: the horizontal streaks across slices 2 and 4 are not due to projectile artefact, they are imaging errors.

[CobrayCommando]

Excellent thread Odd Job, thank you for increasing my knowledge of the subject.

So I would summarise by saying that deflections are not a rare occurence, they are quite common and I have many cases that demonstrate this (not just involving the head and chest, and not all involving bone strikes).

From what I have read I would have to agree. Would you say that there are specific types of bullets that are less likely to do this, perhaps even specific calibers (to settle something in another thread and to satisfy my curiosity) and combinations thereof?

I have read that solid bullets with a meplat, or flat point, generally tend to stay on target, especially if they have high momentum. The meplat makes them penetrate more because it keeps them stable and far less likely to yaw.

If theoretically you knew that several shots you fired had already hit your attacker in the lethal red plate, and the attacker did not cease his assault, where would you recommend aiming? I know this is theoretical because in real life you likely wouldn't see your hits, and in this situation what would you recommend doing?

I recently read a dissertation called "Wound ballistic simulation: Assessment of the legitimacy of law enforcement firearms ammunition by means of wound ballistic simulation" by Jorma Jussila. I am no scientist, and I wonder what your thoughts are on the subject of linking tissue devitalization with kinetic energy dispersed per unit of length traveled by the projectile in tissue. If you haven't read it and are interested PM me and I will email you a copy. It is very detailed and in depth. Essentially I was wondering if, in your estimation, the increased mass of devitalized tissue external of the permanent cavity caused by some ideal bullet fired from a service caliber handgun, that still got a minimum of 12 inches of penetration in calibrated gelatin, would hasten incapacitation or death (by means of devitalised tissue external of permanent cavity) over say, a non deforming FMJ fired from the same handgun? In your opinion what is the relative importance of said devitalised tissue compared to the actual hole left by a bullet?

Thank you for your time