Normally a isolated fibula fracture
will unite on time may be in 6-8 weeks , fibula fracture within 5 cms from the ankle joint or fracture neck of fibula is of little concern where it has to be treated accordingly.
If treated adequately u need be on cast if no open wounds present for 5-6 weeks and do check x-ray after 6 weeks and access again for further line of treatment. no immobilization should last for more than 3 months, it will cause stiffness
of joints which is a major complication.
In your scenario - its 2 yrs post trauma, the fracture should have healed or should be in non-union either way the splint/bandages has to be removed.
If united start weight bearing and physiotherapy
has u will have wasting of the muscles(thigh and leg muscles) and stiffness of joints( knee and ankle). you can do normal activity.
If the fracture is not united causing pain, discomfort , instability, unable to walk or the fracture is close to the ankle joint and its not united then u need to undergo surgery to remove the sclerotic bone and stabilize it with an implant.
If the fracture is not united but no symptoms(pain, instibility,) then removal splint, start weight bearing, physiotherapy and continue normal activity