Some of that has to do with recovering physically from the surgery, some of it has to do with pain medication during the recovery period. When my stepmom had surgery, she couldn't drive the full time she was told not to. She was recovering properly but couldn't brake and was on pain medication. My dad (at a much older age) had the same surgery but was in better physical condition. He didn't drive for a week but was okay after that. When Physical Therapy came to the house, he was already 3 weeks ahead of recovery. His range of motion was excellent, his strength and mobility were good. He had stopped pain mediation 3 days after the surgery. It's different for different folks.