Risk factors for prolonged operative time in femoral neck fracture patients undergoing hemiarthroplasty through direct anterior approach.

BACKGROUND: The use of direct anterior approach (DAA) for hemiarthroplasty in femoral neck fracture patients has recently increased worldwide. However, no previous studies have elucidated or validated risk factors for prolonged operative time in hemiarthroplasty through DAA. Accurately predicting operative time would contribute to and the selection of the most appropriate surgical approach for each patient and the effective use of operating room.

METHODS: Data from 151 femoral neck fracture patients who underwent hemiarthroplasty through DAA were evaluated. A multiple linear regression model of the operative time of hemiarthroplasty was developed, including age, sex, body mass index (BMI), surgeons' DAA experience and approach depth (cm) on the axial computed tomography (CT) slice of the hip as independent factors.

RESULTS: Mean age at admission was 83.8 [±6.3 standard deviation (SD)] years and mean operative time was 93.1 (±21 SD) min. Operative time increased by 20 min for every 1 cm increase in approach depth [partial regression coefficient (B), 20.4; standardized partial regression coefficient (β), 0.68; p < 0.001] and increased 13 min when the DAA was performed by a surgeon with DAA experience of <20 cases (B, 13.1; β, 0.29; p < 0.001). The adjusted R2 of the model was 0.57.

CONCLUSIONS: We demonstrated that increased approach depth and surgeons' DAA experience (<20 cases) are novel risk factors for prolonged operative time in femoral neck fracture patients undergoing hemiarthroplasty through DAA. Surgeons should consider these factors when estimating the operative time of surgery and selecting the most appropriate and safe surgical approach for a patient undergoing hemiarthroplasty.