I broke my arm in the mid 70s when I was in 5th grade. Radius was compound fracture, Ulna was a simple (or vice versa). The bones were surgically set.
I spent at least 3 nights in the hospital.
I wore a cast past my elbow for several weeks and got one below the elbow for several more.
Eddie had also been jumped by four guys, had gravel ground into his face and mouth, and had gone into shock after the attack - he was in and out of consciousness when Officer Nell found him and during his ambulance ride. A greenstick fracture doesn’t have to mean a minor splintering, either - just that the break is not complete. It could still have been pretty angulated. Given the circumstances, it doesn’t seem unreasonable to keep him for further observation, especially if there was reason to be concerned about compartment syndrome, or if they were worried about his ‘asthma’, or if his mother was an overbearing harridan and the doctor was cowed by her.
Would socioeconomic differences account for the discrepancies among above posts regarding hospitalization times during the 1950-60s? My understanding as that more people were pretty much on your own back then when it came to medical expenses, but this also meant that doctors were less stingy about providing care to those who were willing to pay for it since insurance companies weren’t pulling their strings as much.