Surgical Management of Giant Multilevel Aneurysmal Bone Cyst of Cervical Spine in a 10-Year-Old Child: Case Report with Review of Literature (Evid Based Spine Care

In response to the excellent case report and summary on aneurysmal bone cysts by Gurjar et al1 in the November 2012 edition of EBSJ, we felt that some additional points should be brought to the attention of the readers. In themanagement of these difficult but benign lesions, many good points were raised by the authors, but minimally invasive sclerotherapy was omitted. This procedure involves percutaneous puncturing, often repeated injections of a sclerosing agent, traditionally polidocanol and more recently ethanol, owing to complications reported with the former and not seen with the latter. It is a curious omission of the authors because one of the better articles considering sclerotherapy—“Is Sclerotherapy Better than Intralesional Excision for Treating Aneurysmal Bone Cysts?” by Varshney in CORR 2010—is from one of the author’s institution, the All India Institute of Medical Sciences.2 In this Level II study, 94 patientswere prospectively randomized into two treatment groups receiving either repetitive sclerotherapy using polidocanol or an intralesional extended curettage with autograft. With an average followup of more than 3 years, 93% achieved the group’s criteria for healing versus 85% in the curettage control group, yet with a much more favorable complication profile. This injectionbased treatment option has also been left unnoticed by other centers—as much as can be gleaned from the literature—as this form of therapy is likely not available in some institutions without more advanced interventional radiology departments.3 There is concern, however, regarding cervical aneurysmal bone cysts (ABCs) and injection of Ethibloc (polidocanol) following a case report resulting in death. This was felt to be related to tumor involvement with the vertebral artery.4 As noted by Gurjar, preoperative angiography, and if possible, embolization, are requisite studies. In our experience, sclerotherapy has been avaluable tool in the treatment of this disease. For tumors with significant three-column involvement over multiple areas, it may not be possible to remove the lesion in its entirety even though a macroscopic intralesional resection may seem complete. Residual or “recurrent” disease involving one or both vertebral arteries may be seen on MRI in the setting of a solid incorporating fusion and graft. We have found sclerotherapy to be very helpful in those cases to try to get a jump on early “recurrence.” Extension into the bone graft could precipitate implant loosening and pseudarthrosis, which are difficult issues, especially in children.Within the last year, we had five large cervical and two thoracic ABCs with multicolumn and multilevel involvement; four were resected and instrumented, thus far without recurrences. Another was resected without reconstruction and is doing well. Two children have had resection and circumferential-instrumented fusions but have recurrent tumors being managedwith sclerotherapy and serial MRI as the adjuvant. As a standalone treatment, sclerotherapy has not been helpful for the large multilevel, multicolumn tumors, but it is a helpful adjuvant, especially in early recurrence or smaller tumors where resection and reconstruction are unnecessary as discussed by Varshney et al.2 Also worth mentioning is the concept of spinal instability in neoplastic conditions, which does not directly equate with traditional methods of assessing stability in trauma. Destruction by tumor does not usually involve the additional loss of the ligamentous and soft tissue secondary stabilizers, making the assessment of stability much more difficult. Fourney and Gokaslan as well as the Spine Oncology Study Group have illustrated these unique differences to neoplasia.5,6 With respect to the case described by Gurjar et al and its