No abstract

Background and purpose: In younger patients with a femoral neck fracture (FNF), internal fixation is the recommended treatment regardless of displacement. Healing complications are often treated with arthroplasty. We determined the rate of conversion to arthroplasty up to 5 years after fixation of either undisplaced FNFs (uFNFs) or displaced FNFs (dFNFs).Patients and methods: The study was based on prospectively collected data from the Swedish Fracture Register (SFR) and the Swedish Arthroplasty Register (SAR). FNFs in patients aged < 60 treated with parallel pins/screws or sliding hip screws (SHS) registered in SFR 2012–2018 were cross-referenced with conversions to arthroplasty registered in SAR until 2019. The cumulative conversion and mortality rates were determined by Kaplan–Meier analyses and patient- and surgery-dependent risk factors for conversion by Cox regression analyses.Results: We included 407 uFNFs and 389 dFNFs (median age 52, 59% men). The 1-year conversion rate was 3% (95% CI 1–5) for uFNFs and 9% (CI 6–12) for dFNFs. Corresponding results at 5 years were 8% (CI 5–11) and 25% (CI 20–30). Besides a displaced fracture, age 50–59 was associated with an increased rate of conversion in uFNFs. This older group also had a higher mortality rate, compared with patients aged < 50. There was no sex difference for mortality.Interpretation: Adults aged under 60 with uFNFs and dFNFs face an 8–25% risk, respectively, of conversion to arthroplasty within 5 years after internal fixation. This is new and pertinent information for surgeons as well as patients.

Background:The widespread use of intramedullary nails (IMNs) compared with sliding hip screws (SHSs) in extracapsular hip fractures (AO/OTA 31-A1, 31-A2, 31-A3) has been questioned because of a higher complication rate, although the outcome might have improved through more recent implant designs and the learning curve. This study aimed to investigate if there is a difference with regard to the cumulative incidence of conversion to arthroplasty or any reoperation during the first 5 years after IMN or SHS fixation of extracapsular hip fractures.Methods:In this nationwide, observational cohort study, individuals who were ≥60 years of age and were registered in the Swedish Fracture Register (SFR) from 2012 to 2018 due to extracapsular fracture and were primarily treated with an IMN or SHS were followed in the SFR and the Swedish Arthroplasty Register (SAR) for a minimum of 1 year. The primary outcome was the cumulative incidence of conversion to arthroplasty (conversion rate). The secondary outcome was the cumulative incidence of all reoperations (reoperation rate). Both were calculated in a competing risk analysis during the first 5 years.Results:We included 19,604 individuals (70% women), with a median age of 85 years (range, 60 to 107 years). The 31-A2 fracture was most prevalent (52%), followed by the 31-A1 fracture (28%). No significant differences were seen in the 1-year conversion rate after IMN or SHS use (1.0% compared with 0.9% in the 31-A1 fractures, 1.7% compared with 1.3% in the 31-A2 fractures, and 1.3% compared with 1.5% in the 31-A3 fractures) or in the 1-year reoperation rate (1.9% compared with 1.9% in the type-A1 fractures, 3.4% compared with 2.5% in the type-A2 fractures, and 4.0% compared with 5.2% in the type-A3 fractures). Only in 31-A2 fractures were more reoperations seen after IMN use at 2 and 5 years (p < 0.05). The crude 1-year-mortality was 26.4% (5,178 of 19,604), without significant differences between implants.Conclusions:Considering conversion arthroplasty, IMNs and SHSs performed equally well in general. IMN use was associated with more reoperations than SHS use in 31-A2 fractures at 2 years. However, from a clinical perspective, the differences between the implants were small, in particular when considering the competing risk of dying.Level of Evidence:Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.