If you have been told by your doctor that the pain in your knee is “just a little arthritis,” you are approximately one of 70 million Americans who suffer from this degenerative joint disease. Fortunately, a variety of non-surgical and surgical treatments options are available for patients that suffer form osteoarthritis (OA).⁷

Synovial fluid lines a healthy joint, acts as a cushion, and reduces the friction and wear from joint motion. Hyaluronic acid (HA) is a shock-absorbing and lubricating component found in the cartilage and synovial fluid of the joint. Just as cartilage wears down in osteoarthritis, the level of hyaluronic acid in the joint also decreases and loses its shock absorbing elasticity. Intra-articular injections of hyaluronic acid are believed to restore the concentration and elasto-viscousity of the aging, arthritic joint. This treatment is known as viscosupplementation, and is one of the non-surgical options we offer to our patients for the symptomatic treatment of OA.

The treatment includes a total of 3-5 injections in the knee, administered at weekly intervals. Commercial products such as Hyalgan® (Sanofi-Aventis, Bridgewater, NJ), Orthovisc® (DePuy Mitek, Raynham, MA), Synvisc® (Wyeth, Philadelphia, PA), Supartz® (Smith and Nephew Inc, Mississauga, Ontario, Canada) consist of a sterile mixture of sodium hyaluronate from rooster/chicken combs. Therefore, if you are allergic to poultry products you are not eligible for this procedure. Side effects may include some discomfort, pain, redness, heat, or swelling, which normally resolves after a short period. Although it is not a cure, viscosupplementation can provide temporary pain relief (months to years), increased functioning, and delay the time before surgical intervention is necessary.

Recent studies suggest that viscosupplementation may provide disease-modifying benefits by slowing the progression of osteoarthritis in the joint.^8-12 With the potential to decrease inflammation, reduce pain, and increase function, HA injections are being considered for both chronic pain in arthritic joints and acute pain from traumatic sports injuries as well.⁷

When viscosupplementation is combined with an appropriate physical therapy regimen, studies have shown positive results.^1,3,4 Full benefits typically begin after 5 to 9 weeks, and pain relief can last for up to 6 months. Our experience shows three groups: one-third of the patients respond extremely well, one-third see mild benefits, while one-third see no benefits. Hyaluronan injections in one study had favorable results than treating osteoarthritis with naproxen, an over the counter non-steroidal anti-inflammatory (NSAIDs); however, other studies have shown equivocal results.⁶

The appropriate time to use intra-articular injections of hyaluronic acid varies from person to person. Typically, viscosupplementation is considered as an augmentation to other analgesics (pain relievers), such as acetaminophen or other NSAIDs. Some patients find that they are able to “buy time” using viscosupplementation when they are considering arthroplasty, but want to prolong the time to surgery.

Viscosupplementation is just one of the non-surgical tools we use to treat the pain of OA and improve functioning. Surgery can often be delayed when combined with muscle and core strengthening, gait training, range of motion exercises, joint mobilization, and heel wedges.

References:
1. Dougados M, Nguyen M, Listrat V, Amor B. High molecular weight sodium hyaluronate (hyalectin) in osteoarthritis of the knee: a 1 year placebo-controlled trial. Osteoarthritis Cart 1993;1:97-103.

2. Lee S, Park D, Chmell SJ. Viscosupplementation with hylan G-F 20 (Synvisc): pain and mobility observations from 74 consecutive patients. J Knee Surg. 2004 Apr;17(2):73-

4. Puhl W, Bernau A, Greiling H, Kopcke W, Pforringer W, Steck KJ, et al. Intraarticular sodium hyaluronate in osteoarthritis of the knee: a multicentre double-blind study. Osteoarthritis Cart 1993;1:233-41.

5. Wen DY. Intra-articular Hyaluronic Acid Injections for Knee Osteoarthritis. The American Academy of Family Physicians. http://www.aafp.org/afp/20000801/565.html

6. Vioxx Recall: Time to Review Your Arthritis Treatment. Tufts University Health and Nutrition Letter: December 2004.

7. Goldberg VM, Buckwalter JA. Hyaluronans in the treatment of osteoarthritis of the knee: Evidence for disease-modifying activity. Osteo Arthritis Cart 2005; 13, 216-224.

8. Listrat V, Aryal X, Patarnello F, Bonvarlet J-P, et. al. Arthroscopic evaluation of potential structure modifying activity of hyaluronan (Hyalgan) in Osteoarthritis of the knee. Osteoarthritis Cartilage 1997;5: 153-60

9. Frizziero L. Govoni E, Bacchini P. Intra-articular hyaluronic acid in the treatment of osteoarthritis of the knee: Clinical and morphological study. Clin Exp Rheumatol 1998;16:441-9.

10. Pasquali RI, Guerra D, Taparelli F, Boraldi F, et. al. Morphological analysis of knee synovial membrane biopsies from a randomized controlled clinical study comparing the effects of sodium hyaluronate (Hyalgan) and methylprednisone acetate (Depomedrol) in osteoarthritis of the knee. Osteoarthritis Cartilage 2001;9:371-81

11. Guidolin DD, Roncetti IP, Lini E, Guerra D, et al. Morhpological analysis of articular cartilage biopsies from a randomized, clinical study comparing the effects of 500-730 kDa sodium hyaluronate (Hyalgan) and methylprednisone Acetate on primary osteoarthritis of the knee. Osteoarthritis Cartilage 2001;9:371-81 .

12. Jubb RW, Piva S, Beinat L, Dacre J, Gishen P. A randomized, placebo (saline)-controlled clinical trial of the structure modifying effect of 500-730 kDa sodium hyaluronate (Hyalgan) in osteoarthritis of the knee. Int J Clin Pract 2003;57:467-74.