Pattern and prognosis of perioperative deep vein thrombosis after hip fracture: a single-center retrospective cohort study.

Purpose: Patients undergoing hip fracture surgery are at high risk of deep vein thrombosis (DVT) despite standard prophylaxis due to advanced age, surgery or the fracture itself, and immobilization. We investigated the incidence, pattern, and clinical course of DVT in this population. Methods: Consecutive patients who underwent hip fracture surgery at a single institute were included. Lower extremity vein duplex ultrasonography (DUS) was performed preoperatively and again on postoperative day 7. Pharmacologic and mechanical prophylaxis were applied. Treatment-indicated DVT (TI-DVT) was defined as proximal DVT or isolated distal DVT (IDDVT) with a large thrombus burden (TI-IDDVT). Results: Among 154 patients, 34 (22.1%) had preoperative DVT. Twelve patients had TI-DVT (11 TI-IDDVT) and were excluded from further analysis. In the remaining 142 patients, 39 (27.4%) postoperative DVTs were diagnosed, including 19 (13.3%) TI-DVT. Of these, 3 were proximal DVT and 16 were TI-IDDVT. The multivariate analysis identified operation time and the presence of preoperative IDDVT as risk factors for postoperative TI-DVT. The majority of DVT cases were IDDVT, and we further analyzed the prognosis of IDDVT before and after surgery. Twenty-two non-TI-IDDVT cases were identified in preoperative DUS, half of which became TI-DVT after surgery. Conclusion: Most cases of perioperative DVT after hip fracture occurred as IDDVT. Half of these cases progressed to clinically significant DVT. Preoperative IDDVT represents an important predictor of postoperative TI-DVT. Therefore, preoperative DUS needs to be considered in very high-risk patients to allow earlier identification and timely management.