Treatment Failure in Femoral Neck Fractures in Adults Less Than 50 Years of Age: Analysis of 492 Patients Repaired at 26 North American Trauma Centers.

OBJECTIVES

To assess the operative results of femoral neck fractures (FNFs) in young adults in a large multicenter series, specifically focusing on risk factors for treatment failure.

DESIGN

Large multicenter retrospective cohort series.

SETTING

Twenty-six North American Level 1 trauma centers.

PATIENTS: Skeletally mature patients younger than 50 years with displaced and nondisplaced FNFs treated between 2005 and 2017.

INTERVENTION: Operative repair of FNF.

MAIN OUTCOME MEASUREMENTS: The main outcome measure is treatment failure: nonunion and/or failed fixation, osteonecrosis, malunion, and need for subsequent major reconstructive surgery (arthroplasty or proximal femoral osteotomy). Logistic regression models were conducted to examine factors associated with treatment failure.

RESULTS

Of 492 patients with FNFs studied, a major complication and/or subsequent major reconstructive surgery occurred in 45% (52% of 377 displaced fractures and 21% of 115 nondisplaced fractures). Overall, 23% of patients had nonunion/failure of fixation, 12% osteonecrosis type 2b or worse, 15% malunion (>10 mm), and 32% required major reconstructive surgery. Odds of failure were increased with fair-to-poor reduction [odds ratio (OR) = 5.29, 95% confidence interval (CI) = 2.41-13.31], chronic alcohol misuse (OR = 3.08, 95% CI = 1.59-6.38), comminution (OR = 2.63, 95% CI = 1.69-4.13), multiple screw constructs (vs. fixed-angle devices, OR = 1.95, 95% CI = 1.30-2.95), metabolic bone disease (OR = 1.77, 95% CI = 1.17-2.67), and increasing age (OR = 1.03, 95% CI = 1.01-1.06). Women (OR = 0.57, 95% CI = 0.37-0.88), Pauwels angle ≤50 degrees (type 1 or 2; OR = 0.64, 95% CI = 0.41-0.98), or associated femoral shaft fracture (OR = 0.19, 95% CI = 0.10-0.33) had lower odds of failure.

CONCLUSIONS

FNFs in adults <50 years old remain a difficult clinical and surgical problem, with 45% of patients experiencing major complications and 32% undergoing subsequent major reconstructive surgery. Risk factors for complications after treatment of displaced FNFs were numerous.

LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.