Local lipopolysaccharide injection: a potential novel treatment for heterotopic ossification.

Heterotopic ossification (HO) is a frequent complication after musculoskeletal trauma and surgical procedures. It usually decreases joint mobility and eventually causes loss of joint function. However, there is no satisfied treatment available for HO. Lipopolysaccharide (LPS) is traditionally recognized as an endotoxin. Recently, studies found LPS was associated with loss of bone during bacterial infection and periprosthetic osteolysis after total joint replacement. Cell and molecular biology studies further found that LPS initiated the osteoclast formation, stimulated osteoclast activity and inhibited osteoblast differentiation. Given HO is an abnormality in bone modeling which increases bone mass within extraskeletal soft tissues, we herein hypothesize that local LPS injection might be a potential novel treatment for HO.