Background: On the assumption that an aneurysmal bone cyst has an
intrinsic potential to heal by ossification, a new, minimally invasive
protocol was developed. Demineralized bone powder mixed with bone-marrow
aspirate was introduced into the cyst to halt the expansion phase and to allow
the cyst to ossify. We hypothesized that, in order to induce bone-healing,
cells from the cyst are needed to respond to the inductive material but that
curettage or extensive surgery is not necessary. The goals of the present
study were to assess cyst-healing and to determine the prevalence of
recurrence associated with this new procedure.
Methods: Thirteen biopsy-proven primary aneurysmal bone cysts were
entered through a small incision, and a paste of demineralized bone and
autologous bone marrow was introduced with an applicator. The study group
included three male and ten female patients with a mean age of 16.6 years. The
cyst was located in a long bone in six patients, the pelvis in five patients,
and the scapular glenoid and the calcaneus in one patient each. Five patients
had not received treatment previously, whereas one had had a preoperative
embolization and seven had recurrent lesions that had been treated
Results: After a mean duration of follow-up of 3.9 years, healing
was achieved in eleven patients.
Conclusions: This minimally invasive method is able to promote the
self-healing of a primary aneurysmal bone cyst. As no curettage is required,
the proposed treatment avoids extensive surgery and blood loss and is
convenient for the treatment of poorly accessible lesions such as those
occurring in the pelvis.
Level of Evidence: Therapeutic Level IV. See Instructions
to Authors for a complete description of levels of evidence.