I had one of these for nearly a year. It was on my femur,the bone was broken under anaesthetic,I loosened the frame twice a day and opened it half a mm each time with an Allen key. The bone being broken rather than sawn knits and heals quicker and better. The half mm gap bridges in between cranks so I was breaking and stretching my leg twice a day for a few months. When the required length was achieved the frame was bolted off for the break to mend. I was on crutches for maybe 10 months then a stick. Not the coolest thing at 17! The four pins were removed in out patients,no anaesthetic, just unscrewed with pliers! I still have the pins.