How?long ?to heal a displaced broken neck femur?

Depends on treatment: Femoral neck fractures can be treated with fixation or replacement when displaced. When fixed, you can expect about 12 weeks for the fracture to heal. Weight bearing will be limited during the healing process. If the fracture is treated with replacement, hemi-arthroplasty, recovery is faster. There are limitations with a hemi-arthroplasty. A healed fracture should function well.