Just on the Florida self-defense event (that's the older gentleman shooting back at the two armed thugs right?) I recall it being a .380. So I am wondering, if a larger caliber is required for actually breaking bones to eliminate mobility? I am not sure how directly relevant this is (the breaking bones part) with all the numerous discussions on wound channel and hydrostatic shock (per se) regarding 9mm v .45 ACP.
Or is it STILL "irrelevant" what caliber is used (barring, of course 22LR).
The problem is multifold. When people talk about a shot to the hip that incapacitates a person, at least their motion, they are usually talking about damage to the pelvic girdle and upper femur substantial enough to cause structural failure to the extent that the person can't accomplish locomotor function with it, not because of choice, but because it no longer works correctly. The belief often presented is that hitting the hip/pelvis will cause it to shatter and the person will drop, unable to support themselves, much less be able to walk or run.
Strangely, the term of "hip" is rather generic. When referring to bone material, it usually is the lateral edge of the iliac crest, but can include the iliac blade itself which is the large bone of the pelvis. However, it can also refer to the top portion of the femur inclusive of the trochanters and neck of the femur. Often when you hear that grandma broke her hip, either the ball of the femur has snapped off at the neck or the acetabulum which is the meeting place socket of the ilium, ischium, and pubis with the femoral head/ball. Sometimes the acetabulum fails and the ball of the breaks through inwardly. Usually the story is that grandma fell and broke her hip. This is not what commonly happens. What commonly happens is that the hip breaks (femoral head separation) and grandma falls. Sometims, grandmas really do fall and break their hips and that is going to happen when they land on their side and damage their ilium. There are other scenarios, but those are probably the most common.
So when shooting to break a person's hip and stop their locomotor ability with a handgun round, few people have a clue as to where to shoot to accomplish this task. The trick is to cause a failure at points where the greatest amount of structural stresses occur such that even if the shot doesn't actually complete the job that the weakness created cannot endure stresses on the bone during walking or running and the failure is completed.
Probably the easiest terminal ballistic location would be the head, neck, and trochanters of the upper femur and/or puttng a hole through the head of the femur and acetabulum. Unfortunately, that is a very small target with no readily recognized external landmarks, especially for a person who is wearing clothing.
You could shoot the pubis bones, but this is also a small target. If sufficiently damaged, it will cause the pelvic girdle to be weakened and hugely painful, but may not actually collapse the structure.
The biggest target is the iliac blade. It is big in men and bigger in women. However, unlike the bone closest to the acetabulum which is mostly cortical bone that is dence, the iliac blade is mostly cancellous bone except for a thin layer of cortical bone over it. Cancellous bone looks like a sponge. As such, it does not break like cortical bone as easily with those long spiral sharp edged greenstick fractures you find mid shaft in legs and arms. The porous aspect of the controls the radiating impact forces better and keeps them from spreading as much and you may just get a failure only at the point of contact.
For example, say you have a loose packed snowball and a hard frozen ice ball and you shoot each with a pellet gun. The pellet passes through the snow ball and does some localized boring damage, but the snowball remains intact. The ice ball ends up shattering from the impact.
So the iliac blade is sort of like that loose packed snowball. Low velocity bullets (as in not fired from rifles) can punch neat holes through the iliac blade and the actual structure of the pelvic girdle can remain completely intact except of a hole. If you are shooting at a person and hit their pelvis, more than likely you are going to hit the ilium because it is the largest bone.
You may hit the illium and break off a large chunk of the hip bone such as if your shot hits the person about at the top of their front pants pockets. Away from the acetabulum where the femur meets the pelvis, much of the job of ilium is to simply help complete the circle of the pelvic girdle and to provide attachment and support for muscles and other soft tissue. So you can break of a chunk of it and it will hurt a lot, but yet still have the circle of the pelvic girdle remain intact and so the person can still walk and run with a lot of pain, but the failure needed to physically stop the person isn't achieved.
Check out this birdshot hip shot with no structural failure...
http://www.shutterstock.com/pic-188...picture-of-the-pelvis-after-the-gun-shot.html
Of course, you have to hit the bone if you want that structural failure. People shot in the hip and/or pelvis area often have bullets that don't hit bone...
http://mondoweiss.net/2012/03/sometimes-they-fall-from-the-sky.html
See cases 1 and 3 here. They were shots in the right area, but didn't do bone damage....
http://www.firearmsid.com/Feature Articles/042002/JohannesburgTraumaUnit2.htm
Check out this set of images. Y'all have probably seen it before, but be warned images are not family/word/or queezy stomach safe...
http://www.defensivecarry.com/documents/officer.pdf
The deceased suffered multiple pistol rounds in the pelvic area not of which appeared to have damaged the pevlis. A .223 round shattered much of the iliac blade, but the girdle actually remained intact in that the full circle was still complete.
This was neat. The shot should have shattered the trochanter region at the top of the femur, but the bullet his cancellous bone of a growing youth and so instead of shattering, it bored a hole through the bone.
http://www.google.com/imgres?hl=en&...&w=600&h=478&ei=qgcKUMDnAZGK2QW_zLX5Dw&zoom=1
Check out 30-38 and 39-44. Note that in the first one, a bullet clipped the iliac crest, breaking it, but really only doing minor bone damage. Be sure to look in the other images of bullets in the pelvis area, but no pelvic breakdown.
http://www.jzimaging.com/RSD_wounded_willy_and_damaged_debbie.htm
Rifle shot that did break girdle...
http://www.msnbc.msn.com/id/19419934/ns/us_news-giving/t/journal-shot-while-minding-my-own-business/
Here is a bullet lodged in the pelvic area, but entry was through the chest. Despite the distance traveled in the body, she was in pretty good shape.
http://globalhealthblog.org/2011/07/18/update-from-afghanistan/
Several gunshot wounds to the pelvic region, but no bone damage (or most with no bone damage).
http://www.ajronline.org/content/177/6/1247.full
So will a shattered pelvis take you out of the fight? Maybe not so long as the fight continues where you are. This is a pretty amazing story...
http://www.dailymail.co.uk/news/art...r-fight-Taliban--bullet-shattered-pelvis.html