Cell therapy for bone nonunion: a retrospective study

The aim of this study was to report our experience in augmenting nonunion both with bone marrow mononuclear cells/mesenchymal stem cells (MSCs) and conventional surgical approaches; and for clinical applications, a simple, safe, and reproducible method to effectively treat bone mass loss disease.

A retrospective analysis was performed on stem cell-treated bone nonunion patients from October 1, 2007 to October 1, 2009. Nine patients were categorized into two groups: group 1 consists of 3 patients who received autologous bone marrow mononuclear cells transplantation; group 2 consists of 6 patients who received umbilical cord MSCs (hUC-MSCs) transplantation. All patients accepted conventional surgical treatment and X-ray supervised at 3, 6, and 12 months or so after transplantation, while T cells' subtype was analyzed.

All patients were followed up for 36 months through recheck Out-patient Department and X-ray examination to observe the fracture healing. The mean time for clinical healing was comparable in both groups. The mean time of fracture lines blurred partly, continuous bone callus formation, marrow flow was 3.5M, 6.2M, and 9.1M, respectively, in the human umbilical cord mesenchymal stem cells (hUC-MSCs) treatment group. The compared healing times were 3.8 M, 7.1M and 10.6 months in autologous bone marrow mononuclear cells transplantation, respectively. The serum levels of CD4, CD56, and HLA-DR in hUC-MSCs graft group were negative, while the serum level of CD8 was 7.8% positive. Clearly, there was no significant difference in the percent of T subsets between the 2 groups of T cells' subtype.

Our study showed that patients treated by allograft-augmentation had no complications, reduced treatment- dissatisfaction. The use of hUC-MSCs should be offered to suitable patients in the preoperative consultation as a valuable alternative for autologous grafting and larger clinical trials should be considered in the future.