Clinical character and surgical interventions of solid variant of aneurysmal bone cyst in the iliac bone

Objective To retrospectively study the character and surgical interventions of solid variant of aneurysmal bone cyst in the iliac bone. Methods All the clinical data of 6 cases of solid variant of aneurysmal bone cyst arising in the iliac bone which underwent surgical treatment in our department from January 2002 to March 2014 were retrospectively analyzed, including 5 males and 1 female. The patients ranged from 21 to 66 years old at diagnosis, with an average age of 44.0 years old. 1 patient underwent massive resection of the iliac bone, while other 5 patients underwent intralesional treatment. 2 patients underwent allograft and 1 patient underwent bone cement reconstruction, with titanium rod to strengthen pelvic ring and acetabulum. 1 patient underwent packing with osseous granula on the top of the acetabulum and bone cement. 1 patient underwent bone cement reconstruction with Steinmann Pin and occurred diffused wound bleeding then local radiotherapy was given. Results The average age of patients was 44.0 years, which was older than those who had common aneurysmal bone cyst or giant cell tumor. X-ray of the pelvis revealed an expansile, lytic lesion located centrally with partially-sclerotic margins, and a pelvic CT confirmed the plain radiographic findings more obviously. MRI of the pelvis revealed that the expansile iliac bone lesion was equal intensity on T1WI. T2WI and post-contrast images showed heterogeneous signal and enhancement. The signal of soft tissue edema nearby the tumor margin could be found in 3 cases. The operative time ranged from 80 to 240 min (mean, 110 min). The intraoperative boold loss ranged from 300 to 1 600 ml (mean, 900 ml). The followup period ranged from 3 to 141 months (mean, 41.1 months). There were no local recurrence and loosen of internal implants in all patients. Conclusion Solid variant of aneurysmal bone cyst are rarely seen in the iliac bone and the early clinical manifestation is atypical, which is due to a reactive vascular process of native bone. So we conclude intralesional treatment with allograft or bone cement reconstruction is a reliable option for solid variant of aneurysmal bone cyst in the iliac bone. Local radiotherapy with small dose is also reliable option for the patients who have diffused wound bleeding after operation. Key words: Ilium; Bone cysts, aneurysmal; Treatment outcome; Radiotherapy