Injections in Orthopedics
Osteoarthritis is the most common form of arthritis, and can be a major source of disability. Many older patients continue to be active in sports-related activities; therefore, the treatment of the active patient with osteoarthritis is becoming more common. Intraarticular corticosteroids have been widely used for the treatment of osteoarthritis. There are no guidelines for the administration of corticosteroids, and they can be associated with increased risk of tendon rupture and infection. Viscosupplementation has gained popularity in the treatment of osteoarthritis of the knee. Intraarticular injections of hyaluronic acid have shown to decrease pain and improve functional outcomes.
Osteoarthritis is the most common form of arthritis, and can be a major source of disability. Traditional nonoperative treatment includes activity modification, weight loss, exercise, assistive devices, nonsteroidal antiinflammatory medications (NSAIDs), analgesics, and corticosteroid injections. Specifically, NSAID treatment is associated with significant morbidity to the gastrointestinal system. The economic burden of the gastrointestinal side effects of NSAIDs is estimated to exceed 500 million annually. Surgical treatment of osteoarthritis of the hip and knee is effective, but not indicated for early stages of the disease in all patients. There are also potential complications and enormous costs associated with surgery.
Since the early 1950s, intraarticular corticosteroids have been widely used to manage arthritic conditions. Intraarticular corticosteroids are accepted as an important treatment modality, but currently there are no guidelines in regard to administration. Even less information is known in regard to intraarticular corticosteroid injections and the treatment of sports injuries.
In recent years, intraarticular viscosupplementation with hyaluronate-derived products has gained popularity as a modality for the treatment of osteoarthritis of the knee. Hyaluronic acid provides the elastic and viscous function of synovial fluid, protecting the joint from compressive and shear forces. The content of synovial fluid (lubricating fluid of joint), in the presence of osteoarthritis, has a decreased concentration and molecular weight of hyaluronic acid. This process reduces the viscosity and the protective function of the synovial fluid.
The initial rational for the intraarticular injection of hyaluronic acid was to restore the viscoelasticity of synovial fluid. Several studies have shown that injected hyaluronic acid can augment the flow of synovial fluid, normalize the synthesis and inhibit the degradation of endogenous hyaluronic acid, and relieve joint pain.
Corticosteroids
Mechanism of Action
Corticosteroids are a well-known anti-inflammatory. Recent studies have shown that intraarticular corticosteroid injections .
Indications
Intraarticular corticosteroid injections are frequently used to treat acute and chronic inflammatory conditions. Injections decrease inflammation and swelling, which decreases pain and increases joint mobility. Results vary, depending on the type of joint injected. Small nonweight-bearing joints have better results that larger weight-bearing joints . The intraarticular corticosteroid cannot prevent the pain derived from weight-bearing forces across the joint. The literature has shown that intraarticular corticosteroid injections for the treatment of osteoarthritis can be variable. Intraarticular corticosteroid injections are commonly used for rheumatoid arthritis, and show excellent long-term pain relief. Therefore, it is thought that the primary effect of the corticosteroid is on the synovium. Other indications for intraarticular corticosteroid injections are for adhesive capsulitis of the shoulder. Several studies have shown improved motion up to 6 weeks after injection. There is no clear, objective evidence for intraarticular corticosteroid injections on the treatment of osteoarthritic or sports-related injuries of knees, ankles, shoulders, acromioclavicular joints, lumbar facet joints, and smaller hand and foot joints. Injections around joints are associated with significant risk. Corticosteroid injections could cause ligament and tendon rupture, which is the reason many orthopedists do not recommend corticosteroid injections in these locations.
The treatment of bursitis and tedonitis, such as the subacromial bursitis, greater trochanteric bursitis, and medial/lateral epicondylitis, are common, and results have varied in the literature.
Contraindications
Suspicion of infection is the main contraindication to intra-articular corticosteroid injection. Active infection of the skin and overlying tissues increases the risk of inoculating the joint during injection. Other absolute contraindications are hypersensitivity, presence of a joint prosthesis, and uncontrolled bleeding diathesis. Relative contraindications include anticoagulation therapy, joint instability, poorly controlled diabetes, and adjacent skin abrasions. Direct injection into a tendon or ligament should always be avoided due to the risk of rupture.
Complications
Adverse effects of corticosteroid injections include local and systemic effects of the medication. The local effects include tendon and ligament rupture, cutaneous atrophy at the injection site, calcification of the joint capsule, and infection.
Viscosupplementation
Properties of Hyaluronic Acid
In osteoarthritis, the concentration and molecular weight of hyaluronic acid is reduced. There is a decreased interaction between the hyaluronic acid molecules, which results in lowering the viscosity and elastic properties of the synovial fluid. The lower viscosity creates increased stress forces, which can permanently damage the delicate articular cartilage. The lower viscosity creates an environment that reduces the barrier and filter effects of the synovial fluid. This reduces the nutrient availability and waste removal functions that are vital for the survival of articular cartilage.
Hyaluronic acid has both viscous and elastic properties. At high shear forces, hyaluronic acid exhibits increased elastic properties and reduced viscosity. The opposite is true with low shear forces. Therefore, hyaluronic acid acts as a shock absorber during fast movements, and a lubricant during slow movement. Hyaluronic acid also has several antiinflammatory effects.
Intraarticular hyaluronic acid was found to be equivalent to indomethacin (a pain killer) in reducing pain.
Viscosupplements
The use of hyaluronic acid for viscosupplementation began in the late 1960s by Biotrics, Inc. (Arlington, Massachusetts). The source material was taken from human umbilical cord and rooster combs. The hyaluronic acid could be purified, and was initially injected into race horses after traumatic injuries. In recent years, developers have targeted several properties that are important for the human application of hyaluronic acid.
The hyaluronic acid products that are available in India are Synvisc (Biomatrix, Ridgeford, New Jersey), Hyalgan (Sanofi, New York, New York). They are approved for use in patients with osteoarthritis of the knee. These products are derived from rooster combs; then the hyaluronic acid is purified and the noninflammatory hyaluronan product is isolated.
Clinical Safety
Hyaluronic acid has approximately a 1% incidence of side effects per injection. The most common side effects are local reactions of the knee such as swelling, pain, and increased warmth. This type of reaction typically lasts for 1 to 2 days.
Clinical Results
There have been numerous studies evaluating the efficacy of hyaluronic acid for the treatment of osteoarthritis.
In a 12-week study by Scale et al, the authors demonstrated a significant improvement in pain, activity, and patient/doctor global assessment. They also found a significant improvement with a three-injection regimen compared with a two-injection regimen.
Summary
There are many stages of osteoarthritis, in various locations, and in different patient populations. Corticosteroids have been used for many years in the treatment of osteoarthritis. They are relatively inexpensive and safe, but do not have clear, long-term benefits, and can damage collagen structures surrounding joints. Orthopedic surgeons need to continue to use corticosteroids cautiously and conservatively. As older patients increase their activity and demand on their joints, there needs to be further research into the value and efficacy of hyaluronic acid for osteoarthritis of the knee.
Osteoarthritis is the most common form of arthritis, and can be a major source of disability. Many older patients continue to be active in sports-related activities; therefore, the treatment of the active patient with osteoarthritis is becoming more common. Intraarticular corticosteroids have been widely used for the treatment of osteoarthritis. There are no guidelines for the administration of corticosteroids, and they can be associated with increased risk of tendon rupture and infection. Viscosupplementation has gained popularity in the treatment of osteoarthritis of the knee. Intraarticular injections of hyaluronic acid have shown to decrease pain and improve functional outcomes.
Osteoarthritis is the most common form of arthritis, and can be a major source of disability. Traditional nonoperative treatment includes activity modification, weight loss, exercise, assistive devices, nonsteroidal antiinflammatory medications (NSAIDs), analgesics, and corticosteroid injections. Specifically, NSAID treatment is associated with significant morbidity to the gastrointestinal system. The economic burden of the gastrointestinal side effects of NSAIDs is estimated to exceed 500 million annually. Surgical treatment of osteoarthritis of the hip and knee is effective, but not indicated for early stages of the disease in all patients. There are also potential complications and enormous costs associated with surgery.
Since the early 1950s, intraarticular corticosteroids have been widely used to manage arthritic conditions. Intraarticular corticosteroids are accepted as an important treatment modality, but currently there are no guidelines in regard to administration. Even less information is known in regard to intraarticular corticosteroid injections and the treatment of sports injuries.
In recent years, intraarticular viscosupplementation with hyaluronate-derived products has gained popularity as a modality for the treatment of osteoarthritis of the knee. Hyaluronic acid provides the elastic and viscous function of synovial fluid, protecting the joint from compressive and shear forces. The content of synovial fluid (lubricating fluid of joint), in the presence of osteoarthritis, has a decreased concentration and molecular weight of hyaluronic acid. This process reduces the viscosity and the protective function of the synovial fluid.
The initial rational for the intraarticular injection of hyaluronic acid was to restore the viscoelasticity of synovial fluid. Several studies have shown that injected hyaluronic acid can augment the flow of synovial fluid, normalize the synthesis and inhibit the degradation of endogenous hyaluronic acid, and relieve joint pain.
Corticosteroids
Mechanism of Action
Corticosteroids are a well-known anti-inflammatory. Recent studies have shown that intraarticular corticosteroid injections .
Indications
Intraarticular corticosteroid injections are frequently used to treat acute and chronic inflammatory conditions. Injections decrease inflammation and swelling, which decreases pain and increases joint mobility. Results vary, depending on the type of joint injected. Small nonweight-bearing joints have better results that larger weight-bearing joints . The intraarticular corticosteroid cannot prevent the pain derived from weight-bearing forces across the joint. The literature has shown that intraarticular corticosteroid injections for the treatment of osteoarthritis can be variable. Intraarticular corticosteroid injections are commonly used for rheumatoid arthritis, and show excellent long-term pain relief. Therefore, it is thought that the primary effect of the corticosteroid is on the synovium. Other indications for intraarticular corticosteroid injections are for adhesive capsulitis of the shoulder. Several studies have shown improved motion up to 6 weeks after injection. There is no clear, objective evidence for intraarticular corticosteroid injections on the treatment of osteoarthritic or sports-related injuries of knees, ankles, shoulders, acromioclavicular joints, lumbar facet joints, and smaller hand and foot joints. Injections around joints are associated with significant risk. Corticosteroid injections could cause ligament and tendon rupture, which is the reason many orthopedists do not recommend corticosteroid injections in these locations.
The treatment of bursitis and tedonitis, such as the subacromial bursitis, greater trochanteric bursitis, and medial/lateral epicondylitis, are common, and results have varied in the literature.
Contraindications
Suspicion of infection is the main contraindication to intra-articular corticosteroid injection. Active infection of the skin and overlying tissues increases the risk of inoculating the joint during injection. Other absolute contraindications are hypersensitivity, presence of a joint prosthesis, and uncontrolled bleeding diathesis. Relative contraindications include anticoagulation therapy, joint instability, poorly controlled diabetes, and adjacent skin abrasions. Direct injection into a tendon or ligament should always be avoided due to the risk of rupture.
Complications
Adverse effects of corticosteroid injections include local and systemic effects of the medication. The local effects include tendon and ligament rupture, cutaneous atrophy at the injection site, calcification of the joint capsule, and infection.
Viscosupplementation
Properties of Hyaluronic Acid
In osteoarthritis, the concentration and molecular weight of hyaluronic acid is reduced. There is a decreased interaction between the hyaluronic acid molecules, which results in lowering the viscosity and elastic properties of the synovial fluid. The lower viscosity creates increased stress forces, which can permanently damage the delicate articular cartilage. The lower viscosity creates an environment that reduces the barrier and filter effects of the synovial fluid. This reduces the nutrient availability and waste removal functions that are vital for the survival of articular cartilage.
Hyaluronic acid has both viscous and elastic properties. At high shear forces, hyaluronic acid exhibits increased elastic properties and reduced viscosity. The opposite is true with low shear forces. Therefore, hyaluronic acid acts as a shock absorber during fast movements, and a lubricant during slow movement. Hyaluronic acid also has several antiinflammatory effects.
Intraarticular hyaluronic acid was found to be equivalent to indomethacin (a pain killer) in reducing pain.
Viscosupplements
The use of hyaluronic acid for viscosupplementation began in the late 1960s by Biotrics, Inc. (Arlington, Massachusetts). The source material was taken from human umbilical cord and rooster combs. The hyaluronic acid could be purified, and was initially injected into race horses after traumatic injuries. In recent years, developers have targeted several properties that are important for the human application of hyaluronic acid.
The hyaluronic acid products that are available in India are Synvisc (Biomatrix, Ridgeford, New Jersey), Hyalgan (Sanofi, New York, New York). They are approved for use in patients with osteoarthritis of the knee. These products are derived from rooster combs; then the hyaluronic acid is purified and the noninflammatory hyaluronan product is isolated.
Clinical Safety
Hyaluronic acid has approximately a 1% incidence of side effects per injection. The most common side effects are local reactions of the knee such as swelling, pain, and increased warmth. This type of reaction typically lasts for 1 to 2 days.
Clinical Results
There have been numerous studies evaluating the efficacy of hyaluronic acid for the treatment of osteoarthritis.
In a 12-week study by Scale et al, the authors demonstrated a significant improvement in pain, activity, and patient/doctor global assessment. They also found a significant improvement with a three-injection regimen compared with a two-injection regimen.
Summary
There are many stages of osteoarthritis, in various locations, and in different patient populations. Corticosteroids have been used for many years in the treatment of osteoarthritis. They are relatively inexpensive and safe, but do not have clear, long-term benefits, and can damage collagen structures surrounding joints. Orthopedic surgeons need to continue to use corticosteroids cautiously and conservatively. As older patients increase their activity and demand on their joints, there needs to be further research into the value and efficacy of hyaluronic acid for osteoarthritis of the knee.
