Strength is helpful if you are going to manually do something like hold a reduction while someone nails the tibia/femur or forcefully reduce a distal radius fracture. However, we have plenty of tools/devices to use to get around these issues such as traction/distractors/traveling fixators etc.... In most cases, those tools provide better, safer, and more controlled situations.
At least in my practice, probably the only thing that I do that requires some hard work occasionally is reducing a dislocated total hip.