Joint Injection (3)
(ĐTĐ) - Exercise and other physical activity is important when you have osteoarthritis (OA). But joint pain and stiffness in a knee can make it difficult just to walk, even with medication and other treatments. If that sounds like your situation, or if you can’t take oral arthritis medicine, hyaluronic acid injections may help.
Also called visco supplements, these injections add to the joint’s natural supply of hyaluronic acid, a part of the joint fluid that helps lubricate joints and keep them working smoothly. Hyaluronic acid is also a shock absorber that keeps your bones from bearing the full force of impact when you walk.
When you have osteoarthritis, the concentration of hyaluronic acid lessens. Hyaluronic acid injections are given to supplement the joint area. Experts aren’t completely sure how the injections work, however, because the additional hyaluronic acid stays in the joint for only a matter of hours or days.
Getting a Hyaluronic Acid Injection: What to Expect
Five different brands of hyaluronic acid are available and approved for knee OA:
- Synvisc, Synvisc-One
Depending on which type your doctor uses, you’ll get a single shot or three to five injections spaced a week apart.
The injection procedure is the same for all types. First, the doctor cleans the area. If your knee is swollen with excess fluid, your doctor may inject a local anesthetic to reduce pain, then insert a needle into the joint to withdraw excess fluid. The doctor can usually use the same needle still in place to inject a syringe with the hyaluronic acid preparation into the knee joint.
After an injection, you shouldn’t do any excessive weight-bearing activity for one or two days. Otherwise, you should be able to resume normal activities.
How Effective Are Hyaluronic Acid Injections for Osteoarthritis?
Hyaluronic acid injections seem to work better in some people than others. They may be less effective in elderly people and people with severe OA.
The results of studies on their effectiveness as an osteoarthritis treatment have been mixed. A 2002 study published in Rheumatology found that in the short term, a shot of hyaluronic acid didn't reduce joint pain any better than an injection of salt water. An analysis of seven studies published in the Journal of Family Practice in 2006 concluded that the benefits -- if any -- were slight.
But another analysis of 20 studies from 2004 found that hyaluronic acid injections did lessen pain and increase knee function in people with OA. And an earlier analysis -- of eight clinical trials involving 971 people -- found that people treated with hyaluronic acid did better than those treated with placebo, both at the end of their treatment and six months later.
More recent research has found that the injections relieved pain about as well as nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, or steroid injection. Some studies show that pain relief lasts up to six months or a year.
Hyaluronic Acid Injections for Osteoarthritis: What Are the Risks?
So far, there appear to be no long-term side effects and few short-term side effects from this treatment. The most common side effects in studies were minor pain at the injection site and effusions (build-up of joint fluid), which got better within a few days. Doctors don’t know whether the medication or the injections caused these reactions.
Should You Try Hyaluronic Acid Injections?
Doctors can’t predict yet who will benefit from hyaluronic acid injections. But many doctors consider them for people with significant knee OA symptoms that have not responded to other treatments, and for those who can’t take oral medications or have total knee replacement surgery.
Talk to your doctor to discuss whether the injections might help you. Most insurance companies cover hyaluronic acid injections.
(ĐTĐ) - A number of injectables, including corticosteroids and hyaluronic acid, are now available to treat painful knee osteoarthritis.
Finding relief from knee pain can be a trying experience for the nearly 27 million Americans who live with osteoarthritis. Non-steroidal anti-inflammatory drugs (NSAIDs) help many, but these medications can have serious side effects, including ulcers and serious gastrointestinal bleeding. What’s more, supplements such as glucosamine and chondroitin, which were once hailed as miracles, have not always lived up to their claims in clinical studies.
Although joint replacement surgery is an option for many with advanced osteoarthritis (OA), new types of injections may help postpone the need for knee replacement surgery -- and help relieve pain in people who are not candidates for the surgery.
From steroids and hyaluronic acid to Botox (yes, the same Botox used by millions to paralyze their wrinkles) and stem cells, injectables do have a growing and important role in the multi-pronged approach to treating OA.
“Using injections to treat OA is becoming more mainstream,” says Jennifer L. Solomon, MD, an assistant attending physiatrist at the Hospital for Special Surgery and a clinical instructor at Weill Cornell Medical College, both in New York City. “These are good options that can improve quality of life, especially for people who can’t undergo joint replacement.”
Osteoarthritis Treatments: Steroid Injections
Knees hurt? “Steroid injections can decrease inflammation, which can cause joint cartilage breakdown and can be very effective at relieving OA pain,” says Edward Puzas, PhD, a professor of orthopedics at the University of Rochester at Rochester, NY.
But corticosteroid injections are certainly not a panacea for OA, says Elaine Husni, MD, MPH,the vice chair of rheumatology and the director of Arthritis and Musculoskeletal Center at the Cleveland Clinic in Ohio.
“Steroids are more of a one-time, last-resort treatment, and some people do get a lot of pain relief that lasts for months and months,” she says. Steroid injections can also be used with other treatments such as NSAIDs. “Sometimes we use NSAIDs to get rid of stiffness and steroids for the pain,” Husni says.
Solomon agrees. “If there is a lot of inflammation and acute irritation, steroid injections are the way to go,” she tells WebMD. “If the pain is really more chronic, I still go with hyaluronic acid.”
Hyaluronic Acid Injections Can Help OA
Joint-lubricating injections of hyaluronan or hyaluronic acid also play a role in treating OA. Known as viscosupplementation, these injections basically replenish a substance found in normal joint fluid called hyaluronic acid. Several brands are available, including Euflexxa, Hyalgan, Orthovisc, Supartz, Synvisc, and Synvisc-One.
When injected directly into the knee, these OA treatments allow the cartilage surfaces of the bones to glide over each other more smoothly. They also act as a shock absorber to cushion your knee joint. Although these injections are only approved for the knee, some doctors use them for other arthritic joints, Solomon says.
Hyaluronic injections can help postpone the need for knee replacement surgery in people who have not had success with other OA treatments; but the injections don’t work for everyone. Even if they do work, there can be a large degree of variability in the response, Solomon says.
“Hyaluronic injections are for people with moderate or advanced OA,” Husni says. “If your OA is too advanced or too mild, they don’t work much at all.”
Depending on the injectable your doctor thinks is right for you, treatment involves one or more injections and may relieve symptoms up to six months before repeat treatment is needed.
Botox for Osteoarthritis Joint Pain?
The same Botox injections that have helped millions of Americans eliminate their frown lines, forehead creases, and crows feet may also help relieve OA pain in the knees and shoulders, and the results may last up to three months, says Jasvinder Singh, MBBS, MPH, a staff physician at the Minneapolis VA Medical Center in Minnesota, and assistant professor of medicine at the University of Minnesota in Minneapolis.
Although “promising,” this research is still in its infancy, Singh tells WebMD. “Both corticosteroid and hyaluronic acid injections are accepted, approved, and commonly used treatments for OA, but botulism toxin in the joints is not approved by the federal Food and Drug Administration, so it’s in a slightly different category and needs more evidence that it works and that it’s safe,” he says. Botox (onabotulinumtoxin A) is approved to treat certain wrinkles, arm spasticity, certain neck and eye problems, excessive underarm sweating, and is being studied in a laundry list of other medical conditions, including migraine headache.
Exactly how Botox works in joints is not fully understood, but it may inhibit the release of certain proteins from nerves in the joint, which may decrease the pain sensation.
Treating OA With Stem Cells and Growth Factors
There are other promising experimental injections for treating osteoarthritis on the horizon. Solomon is one of a growing cadre of doctors using the body’s own stem cells and growth factors to stimulate the cartilage’s natural healing process.
“We take blood, isolate the growth factors in the blood, and inject them back into the knee,” she says. “There is not good hard evidence out there yet, but my clinical experience is that it works,” she says.
Stem cells are another possibility. These are unspecialized cells that can turn into other types of cells, and there is some research that suggests stem cells can be used to repair the damaged cartilage in OA.
“There have been some very encouraging animal studies in which we use stem cells to regenerate the cartilage surface in joints,” Puzas says.
These treatments may help change the way OA is treated.
As of now, “you can repair the cartilage or regenerate it,” he says. “Once OA has gone far enough, there is not enough cartilage left to repair, but it may be possible to regenerate it using stem cell technology.”
Osteoarthritis Treatment: It Takes a Village
Treating OA is not just about surgery, or injectables, or weight loss, or bracing or any of the other osteoarthritis treatments out there. Successfully treating OA requires a personalized multi-disciplinary approach. This may include bracing, activity modification, weight loss (if necessary), medications, injections, and/or surgery.
“We are getting away from the one-type-of-treatment approach,” Husni says. “It’s about what you want to do, how active you need to be, and how motivated you are.” Doctors can then design a treatment plan especially for you.
Use of cortisone injections in the treatment of muscle and joint inflammatory reactions is becoming increasingly popular. First popularized by Janet Travell, MD, muscle injections are a remarkably effective adjunct to pharmacologic and physical therapies and are safe and easy to perform. Joint injections, while technically more difficult to perform, also can be of great benefit in the patient's recovery. The purpose of this article is to introduce the basic principles of muscle and joint injections.
Mechanism of Inflammation
Inflammation is one of the body's first reactions to injury. Release of damaged cells and tissue debris occurs upon injury. These expelled particles act as antigens to stimulate a nonspecific immune response and to cause the proliferation of leukocytes. Local blood flow increases to transport the polymorphonuclear leukocytes, macrophages, and plasma proteins to the injured area. A redistribution of arteriolar flow produces stasis and hypoxia at the injury site. The resulting infiltration of tissues by the leukocytes, plasma proteins, and fluid causes the redness, swelling, and pain that are characteristic of inflammation.
Inflammatory muscle and joint injuries are associated with many causes, including the following:
- Muscle strains
- Connective tissue disease
- Degenerative joint disease (DJD)
- Inherited congenital disorders
- Miscellaneous systemic diseases
Initially, the inflammatory reaction serves several important purposes. The influx of leukocytes facilitates the process of phagocytosis and the removal of damaged cells and other particulate matter. Pain and tenderness remind the patient to protect the injured area; however, the inflammatory reaction eventually becomes counterproductive. The extravascular pressure exerted by the edema may retard blood flow into the area and delay healing. Sometimes, the debris coagulates and forms hard masses, scarring, and/or trigger points in the muscle or joint, preventing normal function from returning
Actions of Corticosteroids
The mechanism of corticosteroid action includes a reduction of the inflammatory reaction by limiting the capillary dilatation and permeability of the vascular structures. These compounds restrict the accumulation of polymorphonuclear leukocytes and macrophages and reduce the release of vasoactive kinins. They also inhibit the release of destructive enzymes that attack the injury debris and destroy normal tissue indiscriminately.
Additionally, new research suggests that corticosteroids may inhibit the release of arachidonic acid from phospholipids, thereby reducing the formation of prostaglandins, which contribute to the inflammatory process. Finally, the clinician should appreciate the importance of introducing a needle into the injured area. The needle itself may provide drainage and a release of pressure, and it may also mechanically disrupt the scar tissue in the muscle.
Evaluation of the Patient
As with the treatment of any disorder, a carefully taken patient history and a carefully made physical examination are of paramount importance. Sharp, severe, intense pain suggests the presence of a more acute, traumatic reaction with marked inflammation. Dull, low-grade, chronic pain indicates the existence of a mild inflammatory reaction, a chronic overuse injury, or arthritis. Radiation of pain or additional neurologic symptoms (eg, tingling, burning, numbness) imply additional neurologic involvement. Medication history is important because discontinuation of anti-inflammatory medications often precipitates a reaction. Dietary changes also may precipitate reactions, such as an attack of gout.
The physical examination is performed to assess the location and severity of the reaction. Determination of whether the inflammation is in the muscle, tendon, or joint is of paramount importance. Trigger points in muscles can be easily identified if the clinician uses the appropriate palpation skills. Many clinicians ask their patients to identify the site of greatest discomfort. Patients often know exactly where the source of their pain is, having spent hours localizing it.
Radiographic studies may or may not be beneficial, because it takes a significant amount of effusion for the injury to appear on a routine radiograph. Usually, clinical symptoms are present and treatable long before a radiographic abnormality may be identified. On the other hand, radiographs are important in evaluating for fracture or determining acuity.
If joint and cartilage damage exists, the clinician knows that a long-standing process is involved. Electromyograms (EMGs) are extremely beneficial in determining whether there is a significant neurologic component to the patient's symptoms. This determination is important in targeting injection sites. Blood work can include blood counts and chemistry series. An elevated leukocyte or white blood cell count may indicate infection. An elevated erythrocyte sedimentation rate suggests that a significant myopathic or arthritic process has developed. Elevated rheumatoid factor implies chronic arthritic conditions, such as rheumatoid arthritis. Elevated uric acid levels are sometimes observed in patients with gout.
Treatment of the Patient
Treatment of the patient with an inflammatory condition involves a multidisciplinary approach. Anti-inflammatory medications (eg, aspirins, nonsteroidal anti-inflammatory drugs [NSAIDs], oral prednisone) are indicated in patients with acute and chronic inflammation. It should be remembered that a full therapeutic dose should initially be used. Many patients discontinue their medication after they have begun to feel better, leaving a low-lying inflammatory reaction. This author recommends first prescribing the NSAID for a 10- to 14-day period, with instructions to use up the medication as long as side effects do not develop. This should be followed up with an as-needed (prn) prescription.
Nonnarcotic pain medications, such as Elavil, may be beneficial in reducing the pain associated with inflammatory reactions. Although this is an area of some controversy, the use of narcotic medications is dependent on the severity of the pain, and these drugs should be used only for a limited duration.
In acute situations, rest, ice, heat, splinting, and bracing are important elements of care. With time, physical therapy, massage therapy, and general rehabilitation management become increasingly effective. While injection therapy is relatively safe, there are inherent dangers in any procedure where the skin is pierced, including infection, bleeding, joint ruptures, and perforation of vital structures.
Indications for injection therapy may include any of the following inflammatory conditions:
- Gouty arthritis
- Posttraumatic osteoarthritis (frozen shoulder syndrome)
- Rheumatoid arthritis
- Muscle trigger points
- Carpal tunnel and other entrapment syndromes
- Ganglion Cysts
Precautions for injection therapy include the following:
- Charcot joint (neuropathic sensory loss)
- Neurogenic disease
- Active infections (eg, tuberculosis)
- Immune-suppressed hosts
- Bleeding dyscrasias
- Uncontrolled diabetes
- Joint prosthesis
- Surrounding joint osteoporosis
- Patellar or Achilles tendinopathies (possible tendon rupture)
The packing insert for corticosteroids lists additional significant precautions and contraindications. The physician should be familiar with all of these restrictions before considering injection therapy.
Potential local side effects of corticosteroid injections include infection, subcutaneous atrophy, skin depigmentation, and tendon rupture. These complications often result from poor technique, too large a dose, too frequent a dose, or a failure to mix and dissolve the medications properly.
Regarding injections for myofascial pain, some clinicians prefer to perform trigger point injections of corticosteroid, while others prefer to perform trigger point injections containing only local anesthetics or no medication at all ("dry needling").
The procedure for injection therapy is uncomplicated and well established. The object is to inject the corticosteroid preparation with as little pain and as few complications as possible. The technique is similar for muscle, periarticular, or articular injections. Selection of the site and careful attention to surface and deep anatomy are of paramount importance. Injections in the vicinity of known nerve or arterial landmarks should not be attempted. For example, a lateral epicondyle injection is relatively easy. An injection into at the medial epicondyle (near the ulnar nerve) carries greater risk, and extra care must be taken to identify the nerve, outline its course, and avoid it.
Sterile technique is recommended when performing injections. This added care is needed to minimize the risk of iatrogenic infection and is especially important for intra-articular injections.
Opinions abound regarding whether to give a separate injection with just a local anesthetic (eg, lidocaine) prior to the corticosteroid injection. Some physicians prefer to give 1 injection (the corticosteroid preparation, perhaps mixed with a local anesthetic). Their rationale is that 1 needle is less painful than 2; however, the cortisone injection involves a thicker material, and therefore, a larger-gauge needle is used. Thus, this author prefers a 2-needle technique, feeling that this method is better tolerated by patients. The 2-needle technique starts with the physician anesthetizing the area with a small, 25-gauge needle and waiting 3-5 minutes for the anesthesia to take full effect; a larger-bore needle (21-22 gauge) is then used for the corticosteroid injection.
It should be remembered that the povidone-iodine solution should dry on the skin to have its full antibacterial effect. Just swabbing on the disinfectant and injecting increases the risk of infection. Another important tip is to consider changing the needle used to aspirate the medication into the syringe with the one used to do the injection, especially when using multidose vials. Finally, gentle distraction of the joint being injected may improve accessibility.
The material used for the injection is left to the discretion of the physician. Numerous philosophies and theories exist regarding the use of the different materials that are available. Many physicians prefer a simple, long-acting methylprednisolone preparation. This author prefers a cocktail consisting of equal parts of the following:
- Triamcinolone, which is intermediate acting (40 mg/mL)
- Dexamethasone, which is long acting (4 mg/mL)
For muscle trigger point injections, the needle is inserted directly into the trigger point. The plunger should always be withdrawn to confirm that a blood vessel has not been penetrated before injecting the cortisone. The needle may remain in place but can be moved up and down and turned without withdrawing it from the skin. The needle should be angled into 3-4 areas of the trigger point.
It should be remembered that some of the benefit of the injection is the mechanical disruption of scar tissue. For periarticular injections, the injection should not be made directly into the tendon, lest the patient develop mechanical disruption or weakening of the tendon. Injection of the cortisone is accomplished in small droplets around the area of inflammation. Multiple injections may be required to infiltrate several centimeters of the tendon and muscle. Joint injections are accomplished by inserting the needle directly into the joint. Identification of joint injection sites is beyond the scope of this article, but information can easily be found in several guides to injection. This author's personal favorite reference for muscle trigger points is Myofascial Pain and Dysfunction:The Trigger Point Manual, by J Travell and D Simons.
Following the injection procedure, it is often helpful to ice the area. The injection itself is traumatic and results in swelling and edema, the very problems requiring treatment. Immediate icing of the area reduces this inflammatory response. The patient should be told what to expect. For the first 2 hours, the patient may feel quite comfortable because the area is numb from the local anesthetic. However, this lack of discomfort lasts only 2 hours and is replaced by increased pain that is often worse than the pain experienced before the injection.
The patient should be reminded that a needle has been stuck into a sore spot. This increased tenderness often lasts 2 days and should be treated at home with ice. By warning the patient up front of the level of pain to expect, the clinician can avoid many emergency calls. Obviously, the patient should also be cautioned that any unexpected symptoms (eg, excessive bleeding, allergic reactions, chest tightness, wheezing) should be evaluated immediately in an emergency department.
Frequently, multiple injections are required for comprehensive treatment of the patient. Typically, patients have multiple trigger points, and 3 sets of injections are required; however, it has been this author's observation that administration of up to 10 rounds of trigger point injections may be necessary. Each week, the patient may return with a new "worst spot." This phenomenon tends to be more common in patients with a chronic muscle disorder, such as fibromyalgia or a chronic pain syndrome. Tendon and joint injections generally are limited to no more than 3 in 1 joint per calendar year because of the potential for mechanical disruption of the joint space and structures.
Sibbitt et al found that in patients receiving intra-articular joint injections for pain, the use of ultrasonographic needle guidance appears to significantly improve performance and outcome. Their randomized study of triamcinolone acetonide injection into 148 painful joints showed that in patients who underwent ultrasonographically guided injections, when compared with those who underwent conventional, palpation-guided injections, procedural pain was reduced 43% (p <0.001), absolute pain scores at 2 weeks were reduced 58.5% (p <0.001), significant pain was reduced 75% (p <0.001), and the responder rate increased 25.6% (p <0.01).
Selected Joint Injection Techniques
Injection of the subacromial space for the treatment of rotator cuff tendinitis and shoulder impingement syndrome is a common and useful procedure. This can also be used diagnostically to differentiate between local and referred pain. The posterolateral approach, as follows, is safe and easy to execute:
- Palpate the posterior tip of the acromion, and insert the needle into the space between the acromion and the head of the humerus.
- Angle the needle anteriorly toward the coracoid process.
- Once in the space, draw back on the syringe to ensure that the needle is not in a vascular structure. Resistance during delivery of the medication should be minimal.
- Palpate the inferior medial aspect of the patella, and insert the needle into the space between the patella and femur, parallel to the inferior border of the patella.
- Angle the needle to the center of the patella.
- Aspirate any fluid before performing the injection.
- Deliver the medication, and withdraw the needle.
Hand and wrist
After exhausting conservative treatment, injection is indicated for the treatment of carpal tunnel syndrome, as follows:
- With the palmar surface of the hand facing upward, inject just proximal to the flexor crease and between the palmaris longus tendon and the flexor carpi radialis tendon. The needle should enter the skin at a 45° angle and be aimed toward the tip of the middle finger.
- Advance the needle 1 to 2 cm until resistance is felt.
- Withdraw the needle slightly, and inject the medication. The patient should have mild paresthesias elicited in the distribution of the median nerve. Volume should be minimized to prevent discomfort.
The injection technique for lateral epicondylitis is as follows:
- Palpate the lateral epicondyle.
- With the arm faced palm down and elbow flexed to about 45°, identify a point about 1 cm superior and 1 cm distal to the lateral epicondyle.
- Inject the medication into the point of maximum tenderness.
- Repeatedly withdraw and redirect the needle to infiltrate the area.
The injection technique for bursitis of the greater trochanter is as follows:
- The patient should lie on the unaffected side.
- Identify the point of maximal tenderness, which typically is over the posteroinferior edge of the greater trochanter.
- Advance the needle until it gently contacts bone.
- Withdraw the needle about 0.25-0.5 cm, and administer a partial injection.
- The remaining medication should be infiltrated into the surrounding area in a fan-shaped pattern.
The use of corticosteroid injections can be a useful addition to the treatments employed in treating musculoskeletal and joint injuries and pain. An injection regimen is most effective when combined with other pharmacologic and rehabilitation measures, such as the administration of NSAIDs, the use of stretching, and the employment of treatment modalities (eg, ice, heat). The injection of corticosteroids is a relatively safe procedure that can be managed by specialists and general practitioners alike. Treatment with corticosteroids has been a vital part of the practice of medicine for this author and can be used to benefit many other physicians and their patients.