I am guessing that when some saw this question about causing arm injuries, they may have thought only a simpleton could ask such a question
In reality, what causes arm injuries appears to be a complex question at the very least. For instance, many cite mechanical problems as at least part of the problem. Interesting to know how we could possibly determine this. Not even sure how we can even study the problem with so many variables and variances between individuals.
For instance, what if we had some kids that were all similar in velocity, and had them each throw exactly 100 pitches per week (or less), to live hitters, on the same day each week. Lets say that each kid is not allowed to throw harder than 85 mph and can only throw fastballs. This type of test should address the overuse/rest type concerns noted by PG above. What if some of the kids, were throwing at 100% capacity to reach 85 and some others were only throwing 70% to reach 85, it seems we would predict the ones throwing at 100% would more likely do more damage to their arms. Not so fast. What about the genetic component. Maybe some of the kids maxing out at 85 or some other number actually had superior arm muscles and tissues to begin with that basically made them resistant to injury. How in fact do we sort all this stuff out? There are other variables as well such as conditioning.
Here are some thoughts for some possible long range testing and analysis. Feel free to add to them or critique them
1) Clinics like Doctor Andrew's in Birmingham should require all patients to fill out forms that detail their past histories to try and understand the nature of the problem. This should inlcude pitch counts, rest patterns, weather patterns, family histories, balls thrown at other positions, velocity estimates, types and frequencies of pitches thrown and so forth. Any type of data that can possibly be used to design future regimens should be collected.
2) During the procedures/diagnosis, Doctor's should collect biological data from the arm/shoulder in question. Does this person have any unusual features that led to injury, does there seem to be smaller/weaker tendons and ligmaments involved with this individual, unusual bone structures, etc. Whatever measurments that can be taken to understand what may have led to the injury.
3) It seems to me we need to start studying and collecting data on healthy pitchers and compare it to the data taken above. From the contrasting data, just maybe we can try and sort through some of the obvious variability involved and design regimens to mitigate injury. For instance, I think it would be great if pitchers like Roger Clemons, Greg Maddox, Tom Glavine, and so forth could have their arms and histories studied to find out if there were common threads that led to their long term success and health.
4) PG noted this one above. Maybe as technology improves, the cost for taking an MRI will dramatically decrease. If so, maybe we can have our kids regularly checked on these machines (say once a month) to help guarantee that no damage is being done. That data could also be employed to reduce further injury.
In the end, we may find out it is mostly luck