Patterns and Distribution of Deep Vein Thrombosis and Its Effects on Clinical Outcomes After Opening-Wedge High Tibial Osteotomy.

BACKGROUND: Although a few studies have reported the incidence of deep vein thrombosis (DVT) after opening-wedge high tibial osteotomy (OWHTO), previous studies focused only on symptomatic DVT. Information is lacking regarding the overall incidence of DVT after OWHTO, thrombus location, and the relationship between DVT and clinical outcome. PURPOSE: To determine the overall incidence of DVT and classify the location of DVT after OWHTO. We also determined whether significant differences in clinical improvement exist in patients with and without DVT at 6 months and at 2 years after OWHTO. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: This study included 46 patients (47 knees) who underwent OWHTO. All patients were instructed to perform knee range of motion exercises and partial weightbearing after drain removal. None of the patients received a chemoprophylaxis for DVT except intermittent pneumatic compression. DVT was diagnosed using 128-row multidetector computed tomography performed before discharge on the fourth postoperative day. The location was classified into 6 segments in the distal portion (muscular and axial veins) and proximal portion (popliteal, femoral, and common femoral veins and veins located above the iliac vein). International Knee Documentation Committee (IKDC) score was assessed preoperatively and postoperatively at 6 months, 1 year, and 2 years using a linear mixed model. RESULTS: Although the incidence of symptomatic DVT was 8.5% (n = 4), the overall incidence of early DVT was 44.7% (n = 21). All DVTs were located in the distal portion of the lower extremity vein, and 76.2% of the DVTs were located in an axial vein. The IKDC scores were 33.6 ± 7.2 and 35.3 ± 9.1 (P = .910) preoperatively, 38.1 ± 5.6 and 40.6 ± 8.4 (P = .531) at 6 months after surgery, and 44.8 ± 6.9 and 45.9 ± 11.4 (P = .786) at 2 years after surgery in patients without and those with DVT, respectively. CONCLUSION: The overall incidence of early DVT after OWHTO was 44.7%. DVT after OWHTO was found particularly around the osteotomy site (76.2%). Patients with DVT did not have inferior short-term clinical outcomes after surgery.