Considerations of Surgical Treatment of Aneurysmal Bone Cysts of the Spine in 17 Patients

• (e - Travel Assistance)

Purpose: Aneurysmal bone cysts are benign osseous lesions of unknown origin. They are relatively rare representing 1.4 % of all primary bone tumors. The spine is reported to be involved in 3 -20% of cases. Surgical treatment often consists of intralesional curettage or marginal resection with recurrence occurring not uncommonly. We report on 15 patients with aneurysmal bone cysts of the spine, either primary or presenting with recurrence, treated with en bloc excision and reconstruction or marginal resection in situations where en bloc excision was not possible.

Methods: Fifteen patients (5 female, 9 male) with aneurysmal bone cysts of the spine surgically treated between June 1990 and September 1999 at our institution were retrospectively reviewed. Follow up ranged from 2 - 16.5 years (mean 7 years). Patient age at time of initial diagnosis ranged from 4 years to 44 years (mean 18 years). 9/15 (60%) patients presented to us with tumor recurrence after initial surgical treatment elsewhere. Of these 9 patients, 6 were initially treated with intralesional curettage and bone graft, 3 with marginal resection.

Findings: The cervical spine was involved in 7/15 cases (47%), the thoracic spine in 6/15 cases (40%), and the lumbar spine in 2 cases (13%). In 11 cases ( 73%), the tumor involved the anterior and posterior elements of the vertebra. 5/15 patients (33%), were treated with en bloc resection with anterior and posterior instrumentation. Marginal resection was performed in 10 patients (67%).One intra-operative dural leak occurred in a previously operarted patient. There were 2 cases of Horner's syndrome in patients undergoing re-operation in the cervical spine. No tumor recurrences have occurred at the time of last follow up.

Conclusions: Initial surgical treatment of aneurysmal bone cysts of the spine should be aggressive and complete. Surgical treatment should consist of en bloc excision and reconstruction. When this is not possible, due to anatomical considerations, marginal resection or curettage followed a reconstruction of the affected segment or segments should be undertaken in an attempt to prevent recurrence of these benign but often locally aggressive lesions.

• If noted, the author indicates something of value received. The codes are identified as: a-research or institutional support; b-miscellaneous funding; c-stock or stock options; d-royalties; e-other financial or material support.