Yoshisada Shingaki

Packing with high-porosity hydroxyapatite cubes alone for the treatment of simple bone cyst

In 23 patients, simple bone cysts were treated by curettage followed by packing the cavity with cubes of high-porosity hydroxyapatite (HA). In 22 patients, HA was packed exclusively without autogeneic bone graft. Except in one patient who sustained pathologic fracture at the femoral diaphysis, HA was packed with a fibula strut graft. Each case had an uneventful postoperative course and was followed, on average, two years. Complete healing without cyst recurrence occurred in 18 cases (78%). In three cases--all rapidly growing children--a new cyst appeared between the epiphyseal plate and the HA packing, but the original cysts did not recur. In two multiloculated cysts, the cavities were not filled fully and healing was incomplete, yet there was no cyst recurrence. In the entire group, new bone surrounding HA was roentgenographically evident within an average of 2.3 months. Thus, the result of packing high-porosity HA for simple bone cysts compares favorably with the cure rates reported either with autogeneic bone graft, or topical steroid injection.

Solo Implantation of Porous Cuboidal Hydroxyapatite for the Treatment of Simple Bone Cysts

ABSRACT Solo packing of porous cuboidal hydroxiapatite (HAp) for the treatment of simple bone cyst was performed in 23 cases. New bone formation of the space around HAp in the cysts were demonstrated radiologically in a few months. Complete cure was confirmed in 19 cases(83%) followed over one year(average one year nine months). Even for the large expansive cysts which had been often ineffective by topical steroid injection, complete healing by packing of HAp alone was obtained. In three cases, the cavities were not fully packed with HAp because of bony septa in multilocular cysts. Only in one growing child, new cyst was recurred between the epiphyseal plate and the packed HAp. Thus, this treatment for simple bone cysts is recommended because of high curability and shorter contraction period compared to topical steroid injection, and also recommended because of less invasiveness compared to conventional autogenous bone graft.