Stair Falls: 15+ Potential Injuries (at least)
Throughout the film, Harry and Marv prove to be what the French would call "laissez competent," by falling, hard, down several flights of stairs, on multiple occasions. We decided to lump these incidents together, for brevity.
Diagnosis: "Neither one would be able to get up after these falls, especially at their age. Any of these tumbles would definitely be enough to send them to the ER, immediately: herniated disks, bruised or fractured tail bones, multiple spinal fractures, broken limbs and ribs, serious deep tissue bruising, internal bleeding—and that's just a start. Damage to the coccyx, or tailbone would make it extremely painful and difficult to even stay seated, let alone walk/run. They are old enough to have underlying health problems for the rest of their lives, just based on these falls, alone."