When Do Surgeons Perform Arthroplasty for Minimally Displaced Femoral Neck Fractures?

Purpose: Minimally displaced femoral neck fractures (FNFs) have traditionally been managed with internal fixation. In response to emerging evidence suggesting that arthroplasty may offer better functional outcomes and fewer complications, some orthopaedic surgeons have begun treating more minimally displaced FNFs with arthroplasty. We sought to determine the frequency of this practice and the clinical characteristics that lead orthopaedic surgeons to prefer arthroplasty for minimally displaced FNFs.

Methods: We developed an electronic survey to assess the influence of fracture and patient characteristics on orthopaedic surgeons’ choice to treat minimally displaced FNFs with internal fixation or arthroplasty using clinical vignettes. Sample size calculations determined that 138 completed surveys would facilitate a meaningful analysis. We electronically distributed the survey via an anonymous survey application to members of the OTA, Canadian Orthopaedic Association, and the investigators’ research network.

Results: 142 orthopaedic surgeons completed the survey, with approximately half (46%) practicing outside North America. 36% of surgeons reported performing arthroplasty in at least half of minimally displaced FNFs, while 73% of surgeons indicated that deciding between internal fixation and arthroplasty is difficult for certain minimally displaced FNFs cases. Most surgeons indicated that they would perform arthroplasty for a posterior tilt of 20º (69%) or 30º (94%), varus angulation (90%), or a neck-shaft angle >160º (72%). Conversely, internal fixation was preferred for posterior tilt of <10º (83%) or a neck-shaft angle between 140º and 150º (83%). Patient characteristics influencing surgeons’ treatment preferences included: age (83%), pre-injury mobility or use of walking aids (75%), osteoporosis (62%), and dementia (46%). Sex (12%), body mass index (25%), and frailty index (35%) were less influential. We found an association between the preference for arthroplasty and number of minimally displaced FNFs treated annually (P = 0.033), but none between arthroplasty preference and number of years in practice (P = 0.065). 79% of surgeons agreed that there is a need for a randomized trial comparing arthroplasty to internal fixation for minimally displaced FNFs.

Conclusion: In contrast to existing guidelines and prior practice trends, over one-third of orthopaedic surgeons routinely treat minimally displaced FNFs with arthroplasty. Variation in current practice demonstrates the need for a high-quality randomized trial to definitively determine if arthroplasty leads to improved outcomes, fewer complications, and possibly lower mortality.