A rare case of acute postoperative upper extremity deep vein thrombosis and pulmonary embolus after humeral shaft fixation: A case report and review of the literature.

RATIONALE: Upper extremity deep vein thrombosis (DVT) accounts for only 1% to 6% of all DVT cases but is clinically significant due to risks of life-threatening pulmonary embolism and post-thrombotic syndrome. Despite its low incidence, upper extremity deep vein thrombosis warrants heightened clinical vigilance given its frequently occult presentation and potentially devastating sequelae, as underestimation often delays diagnosis and management.

PATIENT CONCERNS: A 69-year-old woman developed acute-onset chest pain, tightness, and dyspnea on postoperative day 11 following open reduction and internal fixation of a left humeral shaft fracture.The patient reported significant anxiety due to the acute and unexplained nature of her symptoms.

DIAGNOSES: Doppler ultrasound revealed a hypoechoic thrombus in the left brachial vein. Computed tomographic pulmonary angiography confirmed bilateral pulmonary artery filling defects, indicating pulmonary embolism.

INTERVENTIONS: The patient received subcutaneous low-molecular-weight heparin (5000 IU twice daily) for 2 weeks as anticoagulation therapy, followed by transition to oral rivaroxaban (20 mg daily). Supplemental oxygen therapy and prophylactic antibiotics were administered concurrently.

OUTCOMES: Cardiopulmonary symptoms (chest pain, tightness, dyspnea) resolved, left upper limb swelling significantly improved, and serum D-dimer levels markedly declined at discharge. The patient underwent follow-up for 6 months and showed no signs of recurrence.

LESSONS: Maintaining a high clinical suspicion is crucial for diagnosing this uncommon syndrome in patients with postoperative humeral fractures who present with persistent or progressive symptoms - including swelling, pain, and cutaneous coolness - particularly in the presence of risk factors such as long-term steroid therapy, indwelling venous catheters and history of cancer. This study aims to enhance awareness of atypical presentations.