Fur shaved after surgery

Hi everyone.

I'm looking for some advice and to hear about your experiences! Here's my situation: I have a little 8-month-old Pomeranian called Jimmy. He’s just had an operation—a femoral head and neck excision—following a fracture. The vet shaved off a huge amount of his fur: half his body, his leg, and his bottom. I'm really worried that it won't grow back because they say you should never shave a Pomeranian’s coat. Does anyone have any information on this?

Thanks in advance for your replies