Risk factors related to periprosthetic femoral fracture following hemiarthroplasty for displaced femoral neck fracture in aged patients

Abstract

Objective To analyze the risk factors associated with periprosthetic femoral fracture following hemiarthroplasty (HA) for displaced femoral neck fracture in aged patients. Methods From January 2013 to June 2016, 120 patients over 80 years old were treated by HA for displaced femoral neck fractures. They were 45 males and 75 females, with an average age of 85.2 years (from 80 to 97 years). Their fractures were Garden type Ⅲ(72 cases) and Garden type Ⅳ(48 cases). The time from injury to op-eration averaged 5.1 days. The patients were divided into a fracture group and a non-fracture group according to the presence or absence of the periprosthetic fracture. The general data of the 2 groups were compared; multivariate logistic regression analyses were done to indentify the influencing factors associated with periprosthetic femoral fracture. Results The 120 patients obtained a mean follow-up of 26.1 months (from 13 to 48 months). Periprosthetic femoral fracture occurred in 11 cases, giving an overall incidence of 9.2% (11/120). Compared with the non-fracture group, the average age was significantly older, the inci-dence of past fractures was significantly higher, significantly more types of uncemented stem were used, and American Society of Anesthesiologists (ASA) grading was significantly more severe for the fracture group (P 0.05). Multivariate Logistic regression analyses revealed that age [OR=1.268, 95%CI (1.059, 1.517), P=0.010] and type of uncemented stem [OR=0.072, 95%CI (0.008, 0.625), P=0.017] were independent risk factors for periprosthetic fracture. Conclusions The incidence of periprosthetic femoral fracture in the elderly pa-tients may be high following HA for femoral neck fractures. Since age and uncemented stem may be independent risk factors for periprosthetic femoral fracture, surgeons should pay enough attention to them in clinic. Key words: Femoral neck fractures; Arthroplasty, replacement, hip; Periprosthetic fractures; Risk factors; Aged, 80 and over