Post-Traumatic Lymphatic Vessel Thrombosis Treated With Thrombus Removal and Lymphaticovenous Anastomosis: A Case Report.

Lymphatic vessel thrombosis is a rare finding, and its role in the development of lymphedema remains unclear. Secondary lymphedema is usually related to oncologic lymph node dissection, radiotherapy, infection, or major tissue trauma. In contrast, focal lymphatic obstruction after minor limb trauma has rarely been described. We report the case of a 71-year-old woman who developed progressive Stage II lymphedema of the left lower limb after a minor trauma without fracture. Preoperative examination showed persistent lower-limb swelling with a focal medial proximal lower-leg nodule, and conservative treatment with manual lymphatic drainage and compression produced only partial improvement. Venous duplex ultrasound and magnetic resonance imaging excluded venous obstruction, tumor, or muscular injury. Ultrasound suggested a lymphatic rather than venous origin of the focal lesion, while lymphoscintigraphy with SPECT/CT demonstrated an interruption of lymphatic drainage at the medial proximal lower leg, associated with a 17-mm subcutaneous fluid collection consistent with a lymphocele. Intraoperatively, the lymphocele was excised and an intact but dilated collecting lymphatic vessel distal to the obstruction was identified. After opening the vessel, intraluminal thrombotic material was removed, resulting in restoration of spontaneous lymphatic flow. Lymphaticovenous anastomosis was then performed using the recovered lymphatic vessel, with intraoperative confirmation of patency and lymphatic washout. The postoperative course was uneventful, with significant clinical improvement confirmed at 6 months follow-up. This case supports the hypothesis that lymphatic thrombosis may occur after minor trauma and may directly contribute to secondary lymphedema, although longer follow-up and objective outcome assessment are required.