The findings indicated that osteonecrosis development correlated with elevated levels of specific immune markers, including CD62L- monocyte %monocyte, absolute count of CD33− HLA DR + Myeloid cell, CD8br and CD8dim %leukocyte, CD28+ DN (CD4-CD8- %T cell, CD27 on unsw mem B cells, IgD on IgD+ CD38dim B cells, CD28 on CD28+ DN (CD4-CD8-) T cell, CD45 on HLA DR + CD8br TBNK, and CCR2 on monocyte. This evidence concerns the gene CD28 and osteonecrosis.