Interprosthetic Femur Fractures: Systematic Review

Interprosthetic femur fractures (IFF) present unique challenges to orthopaedic surgeons due to the preexisting implants in place, oftentimes advanced age and poor bone quality. Through the development of specific implants and improvement of fixation principles, management of this rare—yet growing—fracture pattern has progressed in recent decades to improve patient outcomes. This study’s aim was to identify patient-related outcomes after undergoing ORIF of interprosthetic femur fractures, including time to union, change in pre-operative ambulatory status, malunion/nonunion, surgical site infections, and revisions. A systematic review of published literature was conducted on Pubmed/MEDLINE and Cochrane Library databases for English language papers published with 12 studies meeting inclusion/exclusion criteria. Studies providing quantitative data comparing time to union, change in ambulatory status, surgical site infections, malunion/nonunion, revisions, and one-year mortality were used in the analysis. Studies lacking quantitative data were excluded. 12 studies were included in this systematic review and graded by MINOR to identify potential biases. The aforementioned patient outcomes were calculated as mean values, ranges, and percentages. Time to union averaged 20.2 (range 6-28) weeks with roughly 18% of patients experiencing a decline in pre-operative ambulatory status. It was found 1.3% of patients experienced surgical site infections that were treated successfully either operatively or nonoperatively. Malunions and nonunions occurred in 1.63% and 6.12% of cases, respectively. Revisions were necessary in 12.6% of cases due to malunion, nonunion, and hardware failure. The one-year mortality rate was 12.8%. Our review demonstrates that interprosthetic femur fractures continue to pose significant challenges in their treatment to both patients and orthopaedic surgeons. With the expected continued growth in the number of primary total hip and total knee arthroplasty performed annually, the incidence of interprosthetic femur fractures will continue to rise. Full femur spanning locked plating is currently the standard of care in fracture patterns with stable prostheses. Therapeutic Level III