Corticosteroid Injection Techniques

Introduction

The ability to access joints has great benefit for diagnosis (rule out infections, hemarthrosis or inflammatory gout) and treatment (delivery of corticosteroids or hyluranoglucans). This introductory talk will focus on some of the basics of the injection of corticosteroids.

History of Corticosteroid Use

Corticosteroid injections have been used for over 50 years for the treatment of many musculoskeletal ailments. Injections are a useful modality for Rheumatologists and Orthopedic doctors as well as the General or Family Practitioner. One a familiarity and comfort level is reached with each technique office based practitioners may offer to their patients a very effective and cost effective treatment.

Care should be made in the selection of who should receive injections. Pitfalls to avoid include: wrong dose of the drug (either too little or too much), injections given too frequently, the drug is administered to the wrong area, poor injection technique allows spread of the dug to adjacent tissues, ignoring an underlying cause of the injury and a failure to address it, and lack of attention to rehabilitation and general strengthening afterwards.

Cortisone injections should not be seen as a panacea or a placebo but one of many tools the sports medicine practitioner has at he disposal.

Injectable Corticosteroids are all synthetic analogues of the hormone cortisol. Cortisol in physiological doses has a regulatory effect on glucose and protein metabolism as well as anti-inflammatory effects via action on polymorph and macrophage migration as well as lymphocyte suppression.

Initially in the 1940s corticosteroids were fist used systemically but as side effects were noted the enthusiasm for their use declined. Systemic steroids still have an important role today either as a large amount over a very short term (pulse dose) for severe systemic inflammatory states or low dose chronic suppressive doses. Systemic steroids do involve a trade off though. At high doses the immune system is globally depressed as well as inadvertent effects such as depression ad osteoporosis. The regular adrenocortical release of cortisone may also become suppressed giving a patient an Addisonan condition- where the patient will not mount an appropriate release of cortisol when appropriate for a given stress. Cortisol is an endogenous hormone like thyroxine- you hardly notice it when you have it but sorely miss it when you need it.

Action of Corticosteroids

In 1951 hydrocortisone was fist used for injection into arthritic knees. Today many synthetic corticosteroids preparations are available.

REFERENCE CHART OF CORTICOSTEROID POTENCIES

Injection techniques in Orthopaedic and Sports Medicine 2 nd edition Stephanie Suanders WBSaunders Londn 2002

Notes-

1.Short acting steroids are more water soluble and are absorbed quicker and also more likely to cause a steroid flare.

2.Use of triamcinolone has a higher antinflammatory effect with a lower minerocorticoid effect compared with methylprenilone. Triamcinolone also tends not to precipitate in the syringe when mixed with lidocaine but precipitation does not have reduction in clinical effectiveness.

3.Long acting corticosteroids are less likely to cause hyperglycemia in diabetic patients.

Soluable forms of corticosteroids are not useful since when injected intraarticularly they rapidly are absorbed into the systemic circulation.

Insoluble steroid suspensions are used instead. The steroid drug gradually is released from a crystalline solution while in contact with the inflamed tissue. Synovial cells uptake the steroid where it is gradually removed into the blood and then cleared.

Corticosteroids are effective anti-inflammatory drugs by their action on cell nuclear receptors in the control of mRNA synthesis on the production of proteins. This affects the production of cytokines and other mediators of inflammation.

Therapeutic goals in the use of intra-articularly steroids

Many of the precise mechanisms of action of corticosteroids are still not fully understood but the outcome of these processes has shown the following clinical benefits.

Suppression of Inflammation in systemic inflammatory diseases such as Rheumatoid Arthritis

Suppression of inflammation in degenerative diseases. Osteoartritic conditions are periodically thought to have flare-ups of remaining cartilage.

Modifying or curtailing inflammatory damage in severe inflammatory states where inflammation and then rehealing in cyclical fashion may contribute to scar formation.

Side effects of Injectable Corticosteroids

• Facial flushing may occur in 1-5% of patients and occurs in the first 24-48 hrs. It is self limited for up to 1-2 days.
• Menstrual irregularities may occur including bleeding in premenarche and postmenopausal women. Mechanism is unknown but though to be due to inhibition of ovulation.
• Infection rate is felt to be low (estimated as low as 1 in 3900 using alcohol swab without sterile gloves).
• Hyperglycemia in Diabetics although not pronounced or sustained and patients should be informed that their sugars will run higher for a short period.
• Pneumothorax has been described for chest wall injections. Having the patient hold their breath and using a short needle helps prevent this. Alternatively phonophoresis may be used to administer the steroid.
• Other rare side effects include dysphoria and nausea. Some patients with generalized myalgia may feel an upbeat temporary general improvement possible from a systemic absorption of corticosteroid.
• Anaphylaxis has been described and all practitioners should be prepared to have resuscitation mediations available. The corticosteroid itself is unlikely to be the precipitant but more likely are the crystal stabilizers or local anesthetic.

Pregnancy and breastfeeding are not contraindications to corticosteroids and steroid are sometimes recommended for the carpel tunnel syndrome of pregnancy.

Local Side effects to corticosteroid injections

• Post injection steroid flares (2-10%)

This is a localized reaction to the crystal suspension and s characterized by an increased pain and swelling at the injection site. It is important do differentiate a steroid flare from a septic arthritis.

Multidose lidocaine vials contain preservatives that may predispose to precipitate with steroid crystals. Using single dose lidocaine may minimize this.

•  Subcutaneous Skin atrophy/ Ski depigmentation. This is more common in superficial injections into subcutaneous tissue. This is more noticeable in dark skin individuals

•  Bleeding or bruising. Bleeding diatheses such as hemophilia are relative contraindications to injections. Some consider this an absolute contraindication in large joint. If absolutely needed factor replacement may be considered in consultation wit a haematologist.

• Other side effects include nerve damage and needle fracture.
• Steroid arthropathy is a common perceived issue but this is a proven side effect. Several papers refute any damage to joints (add references here)

One study had documented a Charcot like accelerated joint destruction in human hips after injection, but this is widely believed to be more due to the natural progression of the hip arthritis rather than the corticosteroids (reference). Oral corticosteroids in high doses are associated with osteonecrosis (reference)

• Tendon Rupture is well documented in load bearing tendons especially the Achilles tendon. Poor technique injecting into a tendon is often responsible. Other modalities such as phonophoresis and ionophoresis that administer cortisone either by ultrasound or charge are much safer in administering steroid near an inflamed tendon. (Look for reference)
• Joint sepsis is rare occurring anywhere from 1 in 17000- 7700 patients (references)

Contraindications of Use

Overlying cellulites

Bacteremia

Coagulopathy or anticoagulant treatment

Joint prosthesis

Septic effusion

More than 3 injections in a weight bearing joint

Lack of response after 3-4 injections

Inaccessible Joints (i.e. Hip for non orthopedic surgeon without fluoroscopy)

Precautions

Avoid injections in patients who cannot rest joint

Aim for peritendinous injection and not into tendon

Avoid needle trauma to cartilaginous surface

Dorsal extensor injection approach preferable to a volar or plantar one.

Use of Local Anesthetic

Often a local anesthetic is added with a corticosteroid for several reasons.

An anasthetic may be administered prior to a steroid to confirm the correct location of the problem. Alternatively cortisone may be administered in the same needle and be a marker of the successful placement of the injection. This has great therapeutic benefit in that the patient can be shown that the relief brought on by the short acting anesthetic will be followed by long term relief after the cortisone takes effect. It is worth reminding patients that this relief brought on by the freezing will be short lived and their pain and stiffness will recur after an hour or so. Their joint may even be more painful than prior to the injection due to irritation and joint distension but this should rapidly decrease.

Dilution of Steroid

Because if the convoluted surface of synovia the absorptive surface area of joints is large and increasing the volume of injected solution enhances the absorption of corticosteroids. Similarly the volume administered may distend the joint capsule and help break up adhesions.

Equipment

Syringes 3cc, 5cc, and 10cc for injection. A tuberculin syringe may be helpful for hand injections. Use 20cc, 30cc for aspirations

Needles 25G or 30G for injections. 1½ Inch length usually adequate for most

18G needle for aspirations

4x4 gauze soaked in alcohol or betadine

Hemostat can be used for stabilizing a needle if planning to do a injection after aspiration

Gloves

Lidocaine 1% or 2% (always without epinephrine since vasoconstriction will inhibit diffusion into tissue). As a general rule more lidocaine is better than less. If more volume is needed to distend a joint you may add normal saline as well to avoid giving too much lidocaine but this is rarely done

Corticosteroids and Athletes

Under the international Olympic category of doping class III drugs (subject to certain restrictions). They are permitted for certain conditions if medically indicated (look up references). Athletes must declare the steroid on their doping control form. Physicians should look for signs of anabolic steroid abuse and be careful to document these (athletes who develop side effects due to anabolics may be quick to deflect these from a corticosteroid treatment)

General Steps for Injections

Make patient comfortable and lie down for most injections except shoulder. Check if patients companion (Parent, spouse or friend) is not a distraction or themselves in threat of fainting. It is not unheard of to have a patient very comfortable but having to deal with a fainting relative in the middle of a procedure. Generally anxious patients may prefer someone with them.

Patients should be disrobed enough to have good visualization yet be comfortable in either their own clothes or a surgical gown.

Palpate bony landmarks and identify where you wish to inject.

Mark the injection site with a retractable ballpoint pen, a needle cap or the circular cap that the steroid vial comes with. This cap gives a nice "target" with gentle pressure.

Do not draw on the patient, as this will most likely be wiped off.

Clean the site with betadine in an Archimedean spiral- that is starting from the centre and radiating out without crossing over areas you have already wiped.

Wipe once with alcohol in the same pattern.

Your impression should still be visible

Do not touch the injection site or guide the needle with your hand.

There is no need to aspirate prior to injection. Your injection site will not be a highly vascular area. Clinicians are rarely surprised to have an unexpected aspiration as a needle fills up with blood or pus. In this instance it is best to not inject and send the aspirate for testing.

Anaesthetizing the Joint

Some clinicians will first freeze a joint with lidocaine with observation in clinic followed by a second injection with corticosteroid if clinical improvement.

The more common approach is to premix lidocaine with the corticosteroid in the same syringe and administering this as a single injection.

Using lidocaine alone has some value in specific clinical situations. In a patient with traumatic or sudden painful weakness of abduction (with normal xrays and no signs of fracture) a lidocaine injection may be used to transiently relieve their pain. Ability to move their arm will rule out a significant rotator cuff tear whereas if their pain is gone and they still can't abduct then a large rotator cuff tear may be present and they may be referred early on to an orthopedic surgeon.

Post Injection Care

Patient may move joint trough full rage of motion to distribute fluid.

Educate patients regarding steroid flare. Consider use of non-steroidal anti-inflammatory to prevent steroid flare. Steroid flare does not decrease the effectiveness of the injection. Patients who have had successful injections with no prior steroid flares may still be susceptible to steroid and should be counselled regarding this possibility regardless of their past history.

When injections are placed near tendons patients should avoid sudden ballistic movements for 2 weeks Exercises should be increased gradually as tolerated

Common sites for injection

Shoulder

AC joint for arthritis, osteolysis

Glenohumeral joint for frozen shoulder, OA

Elbow

Epicondylitis

Olecrannon Bursitis

Wrist/hand

Carpel Tunnel syndrome

Trigger finger

De Qervain's tendonitis

Hip

Trochanteric bursitis

Iiliotibial band tendonitis

Knee

Knee joint- osteoarthritis, aspirate blood, unlock meniscus locked knee

Anserine bursitis

Ankle/foot

Plantar fascitis

Morton's Neuroma

Chronic ankle tendonitis

Miscellaneous

Several other therapeutic uses of corticosteroid injection have been described as well. Some require specialized training and fluoroscopy and are beyond the capabilities of an office-based practitioner.

Shoulder Injection

Posteriolateral Injection Approach

At posterior angle of acromion with needle directed anteriorly under the acromion. This will reach the sub acromial bursa and the long head of the biceps

Ac Joint Injection

Approach AC joint perpendicular to the clavicle at point of maximal pain.

Glenohumeral Joint injection

Anterior approach one thumb lateral and one thumb inferior to coracoid process. Direct the needle perpendicularly and enter the glenohumeral space.

Epicondylitis

For both the wrist extensors and flexors the origins are sheaths of connective tissue arising from the lateral and medial epicondyles.

Inject the corticosteroid at the site of maximal tenderness. Inject deep enough to avoid depigmentation and atrophy.

Olecranon Bursa

Aspiration to remove fluid and relieve discomfort or rule out infection.

Trigger Finger

Avoid intra-tendinous injection insert the needle at the MCP crease from distal to proximal. The needle is inserted with tendon extended and then flexed prior to injection, which will release the needle tip from the tendon if it accidentally enter the tendon. Use

DeQuervain's Insert the needle distally toward proximal direction to avoid intra tendinous injection. The needle should be entered with the tendon flexed and then extended before injection, which will release the tendon from the needle if the tendon is accidentally entered.

Trochanteric Bursitis

Patient lies in their uninvolved side. Direct the needle down perpendicularly down to the bone.

Iliotibial Band Syndrome

Patient lies in their uninvolved side. Direct the needle down perpendicularly down to the bone

Knee Aspiration

There are several approaches to the knee. Learning one well is all that is required

A bulging effusion is easy to aspirate but entering a normal size joint can be difficult.

One approach ( Superiomedial)

Patient is supine with leg extended. Needle is entered a t a spot one finger width superior to the top of the patella and one finger width medial to the medial patellar edge.

Second approach (parapatellar tendon)

With knee flexed needle is inserted either medially or laterally to the patellar tendon

Pes Anserine Bursitis

The pes anserine is the fan like insertion of the gracilis, sartorious, and semimembranosis. Find the point of maximal tenderness and fan injection to bathe area with injection

Plantar Facsiitis

Palpate to area of maximal tenderness and inject into this area from an area 1 cm above the sole from the medial side of the foot. Aim needle towards the calcaneal spur and go towards bone, then pull back a bit and inject. This approach bypasses going through the thick sole of the foot and is much less painful. Inject deep at the facial attachment to avoid atrophy of the fat pad (if injection given too superficially).

Use 1 cc of steroid with 2-3cc of lidocaine.

Morton's Neuroma

Inject from the dorsal surface between the metatarsal heads at a right angle.

Ganglion Cyst aspiration

Use a 30G needle to anaesthetize and then a 18G to aspirate. Aspiration alone may be adequate since there is questionable benefit of additional corticosteroid injections.

References :

Injection techniques in Orthopaedic and Sports Medicine 2 nd edition Stephanie Saunders WBSaunders London 2002

Joint Aspiration and Injection Workshop Robert Sallis American College of Sports Medicine Team Physician Course 1992 Tampa Meeting

Illustrations G Podolsky 2005.