Intra-articular hyaluronic acid injection after arthroscopy of the knee joint

Background. Knee joint lavage is used when conservative measures are insufficient and a joint prosthesis is not indicated.The negative effects of lavage fluids on chondrocytes and the fact that post-arthroscopy (pa.) pain and joint dysfunction may be due to a lack of synovial fluid (SF) led to the development of a SF substitute based on hyaluronic add (HA). Patients and methods. Eighty patients with persistent knee osteoarthritis (OA) pain underwent lavage with debridement if indicated. One group received an instillation of HA pa. (A+HA, n=40) while the other group did not (A, n=40). Results. Post-surgery pain and joint dysfunction improved substantially and similarly in both groups. At 3 months p.a. CGI (clinical global impression), pain on walking and at night, and functional difficulties worsened in A, but remained stable in A+HA (Mann-Whitney: described superiority A+HA). At 1 year pa., these parameters reached proven superiority in A+HA. Conclusion. Joint lavage in knee OA improves pain and function but p.a. instillation of HA provided longer lasting carry-over effects.