VISCOSUPPLEMENTATION,
CORTISONE AND NON STEROIDAL ANTI-INFLAMMATORY DRUGS:
“What
Works and How to Keep it Safe”
William D. Stanish, M.D.,F.R.C.S.(C),F.A.C.S. Professor of Surgery Dalhousie University Director, Orthopaedic and Sport Medicine Clinic of Nova Scotia Halifax, Nova Scotia Viscosupplementation in the Treatment of
Osteoarthritis #1 Hyaluronan in both articular tissues and synovial fluid plays a critical role in contributing to joint homeostasis and maintaining normal function. It has been recognized for many years that in osteoarthritis the molecular weight and concentration of hyaluronan is diminished. #2. Recognition that there is altered synthesis of hyaluronan by synovial sites in osteoarthritis, led to the concept of viscosupplementation. #3 Viscosupplementation was first used to treat post traumatic osteoarthritis in race horses in the early 1970's. It has been used to treat human osteoarthritis in some countries since 1987. #4 Most studies of viscosupplementation with hyaluronan have shown them to be better than placebo and as effective as non steroidal anti-inflammatories in the treatment of osteoarthritis. #5 There are two classes of hyaluronan based products currently available for clinical use. Low molecular weight hyaluronan (0.5 - 1.2 MW) and hylan molecular weight. In general, the higher the molecular weight of hyaluronan product, the longer it resides in the joint. #6 Recent controlled
randomized clinical trials confirm that five weekly intraarticular injections
of hyaluronan in patients with osteoarthritis are generally well tolerated,
provide sustained relief of pain and improved patient function, and were as
at least as effective with fewer adverse reactions as continuous treatment
with Naproxen for 26 weeks. #7 There is accumulating
evidence from animal models of osteoarthritis that hyaluronan based therapy
may be chondro protective. References:
Intra- and Peri-articular Use of
Corticosteroids in the Knee and Shoulder #1 There are few clinical
indications for the use of intra-articular steroids in chronic osteoarthritis. #2 Theoretically
corticosteroids might inhibit cartilage formation and repair: this has been
found in animal studies when injected in very high doses. #3 Osteoarthritis has been
recognized to have an inflammatory component since the turn of the 19th
century; more recent studies continue to corroborate this fact. As such, intra-articular steroids could in
theory slow or halt the disease process.
In the dog model of osteoarthritis, intra-articular steroids reduced
the severity of cartilage lesions as well as the size and number of
osteophytes. #4 A few blinded controlled
trials have demonstrated a statistically significant decrease in subjective
pain perception with steroids at one week after injection of
Triamcinolone. However, at 4 or more
weeks follow-up, differences between control and treatment cases had
resolved. #5 lntra-articular steroids
have a role in managing the acute exacerbation of osteoarthritis. They may offer significant short term
relief and any concerns regarding detrimental effects in the articular
cartilage are academic, particularly in the patient that is nearing total
knee arthroplasty. . References:
Nonsteroidal Anti-Inflammatory #1 The tissue response to
injury initiates a cascade consisting of inflammation and hyperalgesia. After a nauseous stimulus, peripheral
nerves release prostaglandins, substance P and related peptides. #2 The resultant
prostaglandin mediated inflammatory process is characterized by vasodilation,
increased vascular permeability, followed by hyperalgesia. #3 Traditionally the
analgesic properties of NSAIDs have been attributed to their effects on the
peripheral synthesis of prostaglandins.
This would cause a decrease in the inflammatory response to injury,
reducing pain perception. #4 Recent in vivo animal
studies suggest that the central response to painful stimuli may be modulated
by NSAID inhibition of prostaglandin synthesis. #5 Therefore it has been
suggested that NSAIDs can reduce both acute pain and the subsequent
hyperalgesia response via central mechanisms. We may conclude that NSAIDs “will continue to
be used commonly in Sports Medicine and their use can neither be condemned or
strongly recommended. The prudent
Sports Medicine practitioner must weight the benefits and risks of the use of
NSAIDs and decide for each injury whether these drugs should be given”. Reference:
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