Extracorporeal shock waves increase interleukin-10 expression by human osteoarthritic and healthy osteoblasts in vitro.

OBJECTIVE Extra corporeal shock waves (ESW) have been proposed as additional therapy in bone fracture repair and osteoarthrtitis (OA). However, little is known on the effects of ESW on osteoblast metabolism. The aim of this study was to evaluate phenotype changes of healthy and OA human osteoblasts following ESW treatment. METHODS Osteoblasts were isolated from subchondral bone of 13 OA patients and 7 healthy donors. Osteoblasts were treated or not with ESW at different levels of energy and impulses. IL-10, TNF-alpha, CD29/Beta1 integrin, and CD105/endoglin expression was evaluated by flowcytometry. RESULTS Intracellular IL-10 significantly increased using 1000 impulses at 0.055 mJ/mm2 in both healthy and OA osteoblasts in comparison with untreated osteoblasts (p<0.01). Only in the OA osteoblasts CD29 and CD105 expression significantly increased at 500 impulses and 0.17 mJ/mm2 ESW treatment (p<0.05). CONCLUSION ESW are capable of modifying IL-10 expression in osteoblasts. There is evidence that IL-10 can play a role in bone remodelling by inhibiting osteoclast differentiation and this suggests that ESW may favour bone growth and healing. This further supports the use of ESW in treating bone fracture to promote callus formation. However, the possible use of ESW in OA therapy needs further studies since in OA, osteoblast metabolism is already enhanced with bone sclerosis and ESW application may further increase bone deposition and osteophyte formation, leading to a subsequent worsening of the disease.