EFFECT OF HYLAN G-F 20 (SYNVISC®) ON JOINT KINEMATICS, TEMPORAL/SPATIAL PARAMETERS, AND ON PAIN DURING GAIT OF PATIENTS WITH KNEE OSTEOARTHRITIS. Sue A. Sisto*1,2; Quin Bond1; Gerard Malanga3,2 1. Reseach-Human Performance and Movement Analysis Laboratory, Kessler Medical Rehabilitation Research and Education Corporation, West Orange, NJ; 2. Physical Medicine and Rehabilitation, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, NJ; 3. Sports, Spine and Orthopedic Rehabilitation, Kessler Institute for Rehabilitation, Inc. , West Orange, NJ PURPOSE: To determine whether Hylan G-F 20 therapy changes in pain, temporal/ spatial parameters, and kinematis of individuals with osteoarthritis (OA) of the knee joint. BACKGROUNDS/SIGNIFICANCE: Typically, when an adult suffers from OA of the knee, they are presented with conservative treatments consisting of NSAID therapy and physical therapy or surgical intervention to replace the affected knee joint. There is a third avenue of treatment that has become available in recent years. This treatment modality is viscosupplementation that consists of replacing hyaluronic acid in the synovial fluid contained in the knee joint. It has been observed that the synovial fluid of OA sufferers has less hyaluronic acid (HA), and has been shown to be clinically safe, and have the ability to provide pain relief with a minimum of adverse reactions. To date, there have been no studies performed looking at the efficacy of Hylan G-F 20 on the kinematics and temporal spatial parameters of gait after Synvisc injections to the affected knee afflicted with OA. SUBJECTS: Subjects: 10 healthy; 2 men and 8 women ? 40 years of age (mean age 61.3;sd=13.5) who were diagnosed with OA of the knee and who had a walking pain rating of 50-90 mm. Subjects were 165.5 cm tall (sd=11.8cm) and 89.3kg in weight (sd=18.4kg). All participants were ambulatory without assistive devices, OA of a single knee of at least 3 months, had radiographic confirmation of OA at the target joint, pain from OA requiring frequent use (3 days/week) of analgesics or nonsteroidal anti- inflammatory drugs (NSAIDs) for at least 2 months before enrollment, free of any acute disease or trauma leading to secondary OA of the knee must have occurred at least 5 years before study entry. Participants were excluded if they had any prior viscosupplementation therapy, known allergy to avian products or any components of hyaluronan-based injection devices, a presence of inflammatory arthropathy (eg, rheumatoid arthritis, metabolic bone disease, psoriasis, gout, pseudogout, chondrocalcinosis, joint infection, skin diseases or infection in the area of the injection site), history of sepsis in any joint, varus or valgus deformity of the knee greater than 12 degrees, oral corticosteroids or intra-articular injection in any joint within last 3 months, venous or lymphatic stasis in the leg, claudication or PVD, any surgery in either knee, within the last 6 months, current malignancy or treatment within the past 5 years,diabetes requiring insulin, use of an investigational drug or device (including glucosamine and chondroitin sulfate) within 90 days before entering the study, significant psychiatric or neurological disorder, active alcohol abuse or drug abuse within the past year METHODS AND MATERIALS: 3D gait analyses using Vicon Workstation and Polygon Reporting Tool for the kinematic analysis and 2 Bertec Force Plates for the kinetic analysis were utilized. Each participant walked along a 30 foot walkway at self-selected walking speed. The starting position was altered to allow their respective foot strikes to hit the force plates without any instruction to alter the natural gait pattern. Each participant was tested twice with at least one week in between tests to determine the repeatability of gait parameters and pain responses. Participants completed the WOMAC questionnaire that contains domains of pain, physical function, stiffness and a total score and has been validated for the characterization of pain in OA. This was followed by 3 intra-articular injections of Hylan G-F 20 over a 15-day period of the affected knee joint. Each injection contained 2cc (Synvisc) and injected via a standard lateral approach with knee extended. Participants received 3D gait analysis and WOMAC twice before and were repeated 8 weeks after treatment. ANALYSES: There were no statistical differences using a paired T-test between baseline 1 and 2 for the WOMAC, therefore the scores were averaged and compared to the post injection scores. Multi-variate ANOVAs were used to determine differences in temporal/spatial and kinematic dependent variables, with test time as the independent variable and weight as the covariate. RESULTS: : Paired t-tests of the averaged baseline vs. post injection WOMAC scores were significantly different for pain (p=0.00007), stiffness (p=0.0004), physical function (p=0.002), total score (p=0.0006). There were no significant difference in the temporal spatial parameters. Kinematically, the stance knee abduction range of motion (ROM) showed the greatest decrease (14 degrees pre vs. 10 degrees post) post injection though not statistically significant (0.06). Weight did not account for significantly more variance. CONCLUSIONS: These results are preliminary but point to trends in changes in coronal plane motion during stance in, specifically knee abduction. This is coupled with a significant decrease in pain. Therefore, Hylan G-F 20 can improve the gait and pain of individuals who suffer from OA of the knee. This intervention may be utilized to provide an optimal pain-free period in which physical therapists could educate patients about knee mechanics during gait and stair climbing as well as introduce an exercise regimen without the exacerbation of pain. Exercise is likely to aid in reduction of body weight and reduce gravitational forces on the load bearing joints. FUNDING SOURCE: Wyeth Pharmaceuticals and Henry H. Kessler Foundation KEYWORDS: gait analysis, Kinematics, Knee Osteoarthritis, knee pain Copyright 2009 by the American Physical Therapy Association. Requests for reprints should be directed to the corresponding author of the article. 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