The Effect of Subcutaneous Fat Tissue Length and Area on Postoperative Wound Drainage in Patients Undergoing Hemiarthroplasty for Femoral Neck Fracture

Background The aim of this study was to investigate whether subcutaneous adipose tissue (SAT) length by radiograph and SAT area by computed tomography (CT) before femoral neck fracture surgery are associated with surgical wound drainage (SWD) in elderly female patients. Methods We prospectively evaluated 87 female patients who underwent hemiarthroplasty surgery at a level 1 trauma center between May 2024 and January 2025. The patients were classified into 2 groups: those with SWD within 90 days after surgery (group 1) and those without (group 2). SAT area and SAT length were evaluated using CT and hip radiograph imaging, respectively, and the differences between the 2 groups were analyzed. Additionally, we compared demographic data, body mass index, the Charlson comorbidity index, monocyte-to-lymphocyte ratio, neutrophil-to-lymphocyte ratio, neutrophil-to-albumin ratio, albumin values and surgical incision length. Results No statistically significant difference in the length of the peritrochanteric SAT was found between fractured and nonfractured hips across the groups. However, CT scans revealed that the SAT area around the greater trochanter was 102.5 cm 2 (range: 25–175.4) in group 1 and 71.1 cm 2 (range: 20–190) in group 2, indicating a statistically significant difference ( P < .001). Similarly, the SAT area around the anterior superior iliac spine was found to be 132.4 cm 2 (81.6–172 cm 2 ) in group 1 and 82.3 cm 2 (17–179 cm 2 ) in group 2; this difference was also statistically significant ( P < .001). Conclusions The area of SAT is an effective predictor of postoperative SWD in elderly female patients undergoing hemiarthroplasty due to a femoral neck fracture.