Objective:To investigate the therapeutic effects of bridge internal fixation system on the treatment of periprosthetic femoral fracture of Vancouver type B1.Methods:From June 2013 to October 2018, 10 patients with periprosthetic femoral fracture of Vancouver type B1 were treated by bridge internal fixation system at Department of Orthopedics, Zhucheng People's Hospital Affiliated to Weifang Medical College. They were 3 males and 7 females, aged from 65 to 84 years (average, 73.6 years). All patients had received hip replacement due to femoral neck fracture, including 6 hemi-hip replacements and 4 total hip replacements. Fracture had occurred in 9 cases after the primary hip replacement and in one case after revision. The time from primary hip replacement to the present surgery ranged from 1.5 to 4.0 years (average, 2.5 years). Recorded were operation time, intraoperative blood loss, fracture healing time, hip joint function and complications at the last follow-up.Results:In this group, operation time ranged from 65 to 114 min (average, 82 min), intraoperative blood loss from 110 to 320 mL (average, 145 mL). The 10 patients were followed up for 12 to 18 months (average, 15 months). Their X-ray films showed that bony union was achieved in all after 3 to 6 months (average, 4.3 months). According to their hip Harris scores at the last follow-up, 7 cases were rated as excellent, 2 as good and one as fair. Follow-ups revealed no loosening or breakage of implants, infection, femoral prosthesis loosening, fracture or femoral prosthesis displacement.Conclusion:Bridge internal fixation system is a good way to treat periprosthetic femoral fracture of Vancouver type B1, leading to satisfactory short-term outcomes and fine functional recovery.