Unicameral bone cysts: comparison of percutaneous curettage, steroid, and autologous bone marrow injections.

BACKGROUND: The purpose of this study was to compare the outcome of percutaneous curettage with intralesional injection of methylprednisolone and bone marrow for unicameral bone cysts (UBCs). METHODS: This was a retrospective review of 46 children and adolescents with UBC treated with autologous bone marrow injection, methylprednisolone acetate injection or percutaneous curettage alone. Inclusion criteria were a radiological diagnosis of UBC and at least 24 months follow-up from the last procedure. Healing was determined using Neer/Cole 4-grades rating scale. RESULTS: The 3 treatment groups were comparable with regard to age, sex, location of the cyst, and the number of procedures undertaken. At 2 years follow-up, the proportion of patients with satisfactory healing (Neer/Cole grades I and II) was greatest among those who underwent percutaneous curettage (70%) compared with bone marrow injection (21%) and methylprednisolone acetate injection (41%) (P = 0.03). We found no association between healing and age (P = 0.80) nor between healing and sex (P = 0.61). CONCLUSIONS: These results suggest that mechanical disruption of the cyst membrane may be helpful in healing of cysts and that this technique may be preferred to simple intralesional injections. LEVEL OF EVIDENCE: Level III.