No. Simple, stable, well aligned fractures in the right locations, especially in young animals, can heal in a cast or splint. But most significant fractures in adult dogs and cats do best with surgical repair, and pretending otherwise usually trades a surgical bill now for a malunion and a bigger bill later.
Bones want to heal. Left alone, most will, in whatever position they happen to be lying. A femur that heals two centimetres short and rotated is a healed fracture and a ruined leg. This is why the honest question is never will it heal but will it heal straight, stable and pain free. X-rays answer that question, and an independent surgeon can read yours in minutes.
Send the x-rays. We will tell you honestly whether surgery is the only road. From $250.
Sooner is almost always cheaper and kinder than later. Correcting a healing malposition is a smaller job than re breaking and realigning a healed one. If you are watching a crooked callus form with a sinking feeling, get an opinion this week, not after the recheck next month.
Kittens and puppies heal astonishingly fast, which widens the casting window considerably. But their growth plates also raise stakes: a fracture through a growth plate needs precise handling to avoid a deformed adult limb. Age helps; it does not remove the need for good x-rays and judgement.
An independent written opinion on the diagnosis, the technique and the quote. From $250.