Context: Deep vein thrombosis (DVT), a frequent complication of spinal cord injury, is occasionally caused by neurogenic heterotopic ossification (NHO). In most cases of NHO, the hip joint is affected. Herein, we present a case of paraplegia following radiation-induced myelopathy that presented with left leg swelling due to DVT in the common iliac vein (CIV) caused by venous compression by NHO on the anterior lower lumbar spine.

Findings: A 28-year-old man with complete paraplegia due to radiation-induced myelopathy presented with left lower extremity swelling 6 years after the onset of paraplegia. DVT in the left CIV was observed on computed tomography venography. The left CIV was significantly compressed between the NHO at the anterior longitudinal ligament of the lumbar spine and the right common iliac artery, suggestive of May-Thurner syndrome. Slightly distal to that compressed area, the left CIV was significantly compressed by the large NHO at the anterior longitudinal ligament of the lumbar spine.

Conclusions: We believe that such compression of the left CIV would have contributed to the development of DVT. This case shows that DVT might be caused by NHO at the anterior aspect of the lumbar vertebral body, and this may help clinicians identify the main cause of DVT in the leg.

背景：深静脉血栓形成 (DVT) 是脊髓损伤的常见并发症，偶尔由神经源性异位骨化 (NHO) 引起。在大多数 NHO 病例中，髋关节受到影响。在此，我们介绍了一例放射性脊髓病后截瘫病例，该病例表现为左腿肿胀，这是由于 NHO 对前下腰椎的静脉压迫引起的髂总静脉 (CIV) 深静脉血栓形成。

结果：一名 28 岁男性，因放射性脊髓病完全截瘫，截瘫发作 6 年后出现左下肢肿胀。在计算机断层扫描静脉造影中观察到左侧 CIV 中的 DVT。左侧 CIV 在腰椎前纵韧带的 NHO 和右侧髂总动脉之间明显受压，提示 May-Thurner 综合征。在该压缩区域稍远的地方，左侧 CIV 被腰椎前纵韧带处的大 NHO 显着压缩。

结论：我们认为左侧 CIV 的这种压缩会导致 DVT 的发展。该病例表明 DVT 可能是由腰椎前侧的 NHO 引起的，这可能有助于临床医生确定腿部 DVT 的主要原因。