Victor M. Goldberg

Intra-articular hyaluronans: the treatment of knee pain in osteoarthritis Victor M Goldberg1, Laura Goldberg21Department of Orthopaedics, Case Medical Center, Cleveland, Ohio, USA; 2Cleveland Clinic, Cleveland, Ohio, USA The etiology of pain in osteoarthritis is multifactoral, and includes mechanical and inflammatory processes. Intra-articular injections of hyaluronans (HAs) are indicated when non-pharmacological and simple analgesics have failed to relieve symptoms. The HAs appear to reduce pain by restoring both mechanical and biomechanical homeostasis in the joint. There are five FDA-approved injectable preparations of HAs: Hyalgan®, Synvisc®, Supartz®, Orthovisc® and Euflexxa®. They all appear to relieve pain from 4 to 14 weeks after injection and may have disease-modification properties. Although several randomized controlled trials have established the efficacy of this treatment modality, additional high quality randomized control studies with appropriate comparison are still required to clearly define the role of intra-articular HA injections in the treatment of osteoarthritis.Keywords: hyaluronans, knee, pain, osteoarthritis

Total joint arthroplasty is a highly successful procedure for end-stage lower extremity arthritis. Excellent pain relief and significantly improved function is usual after surgery when used for appropriate indications by highly skilled surgeons using contemporary designed components. Future improvement in design and materials to reduce wear will further enhance clinical outcomes and long-term implant survival.

The long term survival of the Miller-Galante I cementless total knee arthroplasty was evaluated by studying prospectively for a minimum of 14 years (range, 14-17 years), 124 consecutive cementless total knee arthroplasties using a Miller-Galante I prosthesis in 99 patients with a mean age of 62 years who had primary or secondary osteoarthritis. Knee function and roentgenograms were evaluated using the Knee Society criteria. Kaplan-Meier survivorship analysis was conducted. Five patients (five knees) were lost to followup; six patients died with six knees in place. Fifteen knees (15 patients) failed and were revised. Thirteen metal-backed patellas were revised. Eight of these revisions also required exchange of the femoral component, but only one tibial tray was revised. One knee (one patient) was revised for an infection. Of the 98 knees not revised (73 patients) observed throughout this study, the average preoperative knee score was 31 (range, 0-47); postoperatively, the average knee score was 91 (range, 72-100). The average function score improved from 28 (range, 10-45) to 84 (range, 50-100). Twenty-four tibial trays (21%) and twenty femoral components (17%) of the 113 knees studied showed osteolysis. This study indicates that osteointegration of cementless tibial components can be successful with screw fixation, although there is a worrisome incidence of tibial and femoral osteolysis. The overall knee survival rate was 87%; however, the tibial component had a survival of 99%.

Hyaluronans are used widely in the treatment of osteoarthritis of the knee. Three commercial hyaluronan preparations currently are available in the United States: sodium hyaluronate (Hyalgan), sodium hyaluronate (Supartz), and hylan G-F 20 (Synvisc). Although the sodium hyaluronates are derived naturally, hylan is chemically modified to increase its molecular weight. All three products have been shown to be well tolerated in clinical trials, however, there have been reports in the literature of pseudoseptic reactions, or severe acute inflammatory reactions, after injections with hylan. Our study reviewed the reported incidence of pseudosepsis. The pathogenic mechanisms and clinical treatment of this reaction are presented.