BACKGROUND: Subtrochanteric fractures, which constitute 5-10% of proximal femoral fractures, are particularly challenging due to their high incidence of nonunion and failure of internal fixation. The incidence of deep venous thrombosis (DVT) in the lower extremities is notably higher among patients with orthopedic trauma, leading to significantly increased healthcare costs and prolonged hospitalization. The number of studies focusing on the incidence and risk factors among the patients with subtrochanteric fractures was quite limited. Therefore, there is a lack of effective methods of identification and predication. The study aimed to examine the occurrence and contributing factors of DVT in the lower limbs following subtrochanteric fractures in patients.

MATERIALS AND METHODS: Retrospective analysis was performed on the patients with subtrochanteric fracture who were admitted from August 2019 to October 2022. All patients received ultrasound doppler scanning to detect lower extremity DVT. Demographic information, comorbid conditions, and serum markers levels from patients including red blood cell (RBC), hemoglobin (HGB), lymphocyte (LYM), triglyceride (TG) and etc. were collected for analysis. Variables that demonstrated significant differences were subsequently introduced into multiple regression models to identify the independent risk factors associated with DVT.

RESULTS: A total of 120 patients were included, including 80 males and 40 females, with an average age of 58.3 ± 16.14years. A total of 51 patients were diagnosed to have DVT, with an incidence of 42.50%. There was significant difference between two groups in terms of albumin (ALB) (P = 0.0008), total protein (TP)(P = 0.019), RBC(P = 0.013), HGB (P = 0.032) and D-dimer levels (P = 0.007). However, multivariate analyses identified increased D-dimer level(>750 ng/ml) and reduced serum albumin as independent factors. The ROC curve indicated that a D-dimer level of 750 ng/ml was the optimal cut-off value for diagnosing DVT in patients with subtrochanteric fractures, with a sensitivity of 56.52% and specificity of 82.35%. The optimal cut-off value of ALB was determined to be 36.6 g/L, with a sensitivity of 73.2% and the specificity of 41.2%. The area under the curve of 0.63 indicates that this cut-off moderately effectively distinguishes between conditions related to ALB levels.

CONCLUSIONS: D-dimer level and serum albumin are independent factors of DVT in patients with subtrochanteric fractures. These data are helpful in assessing risks of DVT, and guiding the subsequent individualized intervention program.