AN IN-VITRO INVESTIGATION INTO THE EFFECTS OF REPETITIVE MOTION AND NONSTEROIDAL ANTIINFLAMMATORY MEDICATION ON HUMAN TENDON FIBROBLASTS

Soft tissue injuries due to repetitive motion are common sports injuri es and are often treated with antiinflammatory therapies. We investiga ted the in vitro effects of repetitive motion and nonsteroidal antiinf lammatory medication on human tendon fibroblasts. In addition, we stud ied the effects related to the presence of inflammatory cells. Repetit ive motion was associated with an increased release of prostaglandin E 2 and increased deoxyribonucleic acid (DNA) and protein synthesis. The presence of nonsteroidal antiinflammatory medication decreased prosta glandin E2 release and DNA synthesis but increased protein synthesis. Contact with macrophages caused a marked additional increase in prosta glandin E2 and a concomitant increase in DNA synthesis. Release of int erleukin-6 by the macrophages also suggested that this cytokine plays a role in the response to repetitive motion. Our results can aid in th e search for a more scientific approach to the treatment of soft tissu e injuries associated with repetitive motion. They suggest that nonste roidal antiinflammatory medication may have potentially negative effec ts during the proliferative phase of a heating since it was associated with decreased DNA synthesis. However, it may be beneficial in the ma turation and remodeling phase since it stimulated protein synthesis.