It's hard to believe that we still don't understand the cracking-knuckles mechanism. The effect is so large!
Pardon the cruelty of my line of thought here... but do other animals exhibit the same effect? And could some intrusive measurements be done inserting probes into the affected areas, possibly damaging the flesh but revealing data? Even if there might be ethical concerns with such experiments today, I'm surprised that they were not carried out in decades past.
I suppose it's not the highest priority research...
The medical profession is like a bunch of garage mechanics that are working on the most complicated, convoluted, and fussy car ever with no manual. They are still reverse engineering our bodies. They are still discovering organs in the human body. (https://www.nytimes.com/2018/03/31/health/new-organ-intersti...)
Snapping Shrimp have a claw designed to produce a cavitation bubble (in seawater, not within the joint itself), which collapses to generate one of the loudest sounds in the ocean.
I'm pretty sure mantis shrimp (stomatopods) do the same thing. Apparently they're capable of smashing through the glass of aquariums if not properly reinforced.
Pardon the cruelty of my line of thought here... but do other animals exhibit the same effect? And could some intrusive measurements be done inserting probes into the affected areas, possibly damaging the flesh but revealing data? Even if there might be ethical concerns with such experiments today, I'm surprised that they were not carried out in decades past.
I suppose it's not the highest priority research...