As a GP for over 30 years, I have noticed a trend in these injuries amongst my patients. It is NOT appropriate to blame the show. Sports generally evolve with time, in the case of netball, ashphalt has been replaced with polished timber, concrete etc, and the design of shoes has certainly evolved.
I used to see very frequent, severe abrasions to girls knees, from slipping on the old asphalt/Dunlop combination, now I see very few abrasions and an increasing number of serious knee joint injuries.
What IS needed is a change to the rules to reflect this evolution in equipment.
It is not enough to say to IMPROVE TECHNIQUE. This involves both the thrower and the catcher, with the catcher at risk of injury if the ball is not at the best trajectory.
By simply allowing the player to ROTATE the first grounded foot [the other foot must remained fixed] will almost certainly eliminate almost all of these internal knee injuries.
I would recommend that this rule be applied to all junior levels of the sport. It would be relatively simple to reverse on entering the older age groups.
If we look at rugby union, a colleague of mine, as a then medical student, suggested a change to the packing of rugby scrums and mauls, simply by ensuring that the pack had decreasing numbers in the second and third row of the pack. When applied to the sport, this IMMEDIATELY put a stop to the previously frequent severe neck injuries suffered by players in the front row. It is now an international rule.
We need the same in netball.