Humerus fracture (while squatting)

[Wrong_Acanthaceae599]

Male
43 yo
76 kg
Squat 67.5 kg
Press: 20 kg
Bench: 37.5 kg
Deadlift: 85 kg

I had an injury 3 weeks ago: spiral fracture of the let humerus. It was displaced so surgery was necessary, it is fixed with an intramedullary nail. I stayed one week hospitalized. I will be non weight bearing for 3-4 more weeks at least. I can move my arm although with limitation.

Before the incident, I was at 79 kg with 18% bodyfat (I have a balance that measure BF). I had progressed from 75 kg/17.5% BF before I started lifting weight (4 months of work, I know this was slow gains, I started very de-conditioned due to suffering from Ankylosing Spondylitis).

Now I weight 76 kg and 18%BF I lost nearly all gains in 3 weeks (hospital food sucks!). Nutrition now I am at home so higher in protein but I guess the surplus goes into bone and incisions repair. I know my left arm has atrophied due to the surgery (they needed to access behind the triceps so it was cut in part). But my entire upper body seems to have lost (I think my legs did not lose anything). How should I approach regaining the loss ? I would like to focus on an approach with lots of upper body, including exercises that might work only for partial ROM.
I assume I will need significant work to recover some ROM in arm and basic strength before lifting. Also there might be a mental bloc: my arm broke while squatting (67.5 kg work set, second set).

[Mark Rippetoe]

Bones don't just break for no reason. The squat does not apply dynamic force to the humerus. Do you have bone cancer?

[Wrong_Acanthaceae599]

Bones don't just break for no reason. The squat does not apply dynamic force to the humerus. Do you have bone cancer?

Not to my knowledge. Osteoporosis is a more likely possibility and I will try to get a Dexa scan once I am healed.