Practical guide to joint and soft tissue injection techniques James Galloway MRCP and Marwan Bukhari PhD, FRCP

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1 Practical guide to joint and soft tissue injection techniques James Galloway MRCP and Marwan Bukhari PhD, FRCP Figure 1. The authors encourage a medial approach to injection of the knee joint; a combination of 40mg triamcinolone acetonide and 4ml lidocaine is recommended Musculoskeletal conditions account for a vast number of attendances in primary care. Treatment of these problems involves a number of therapeutic options, including intra-articular aspiration and injection. Joint injections were first attempted in the 1920s, using substances such as lactic acid or petroleum jelly. It was not until the early 1950s that intra-articular injections of steroids was introduced and shown to be helpful. 1,2 They are now the most frequently performed procedure in rheumatological practice. 3 Indications Joint injection The primary indication for joint injection is inflammatory arthritis 4 (eg rheumatoid arthritis, spondylarthropathies). Many patients will experience prolonged improvement up to six months from a single joint injection. The longerterm benefits of intra-articular steroids have been less well defined. There is limited evidence that supports their role in reducing synovial inflammation and destruction, and no evidence suggesting that they cause adverse effects on the joint when given in appropriate doses at not more than three or four times per year. 1,2 Osteoarthritis (OA) is a weaker indication for steroid injection a single trial has shown no benefit of intra-articular steroids over saline, although other studies have been more optimistic. 5 However, in practice, many rheumatologists use intra-articular steroids for OA with apparent success. Soft tissue injection There are many soft tissue injections that are regularly performed Steroid injections are a key tool in the management of musculoskeletal conditions and are now the most frequently performed procedure in rheumatological practice. Here, the authors illustrate the correct technique for administering these injections and highlight some of the points to consider. for the treatment of localised inflammation. These include trochanteric bursitis, flexor tenosynovitis, medial or lateral epicondylitis, and carpal tunnel syndrome. Joint aspiration The usual indication for joint aspiration is to evaluate an acutely swollen and inflamed ( hot ) joint. Synovial fluid analysis allows differentiation between crystal arthropathy and sepsis. There is also some evidence to support the routine aspiration of joints prior to steroid injection to improve efficacy. 6 Type of agent to use (see Table 1) Should lidocaine be mixed with the steroid? Many rheumatologists will mix some local anaesthetic with their steroid preparation for injection. Prescriber 19 October

2 Available Depo-Medrone Kenalog 40mg/ml 25mg/ml (1ml doses 40mg/ml Adcortyl 10mg/ml vials) (1, 2 or 3ml vials) (both available in available premixed 1ml vials) with lidocaine Advantages possibly causes possibly causes less associated soft less postinjection less postinjection tissue atrophy Disadvantages crystal precipitates shown to be less can form if mixed efficacious in with lidocaine joint injection Typical site/ dose knee 80mg 40mg shoulder 80mg 40mg subacromial 40mg 20mg bursa ankle 40mg 20mg soft tissue Table 1. Commonly used preparations for joint injections There have been several studies over the years that have not conclusively shown benefit of this practice. However, there are some theoretical reasons why it may be of benefit: Absolute sepsis within the joint or soft tissue prosthetic joints injection into a tendon Relative in the joint postinjection when performed previously active psoriatic lesions (or other skin disease) at the site of injection oral anticoagulation (although experienced injectors may proceed with caution) Table 2. Contraindications to joint injection Methylpred- Triamcinolone Hydrocortisone nisolone acetonide 25mg there may be a volume effect of the local anaesthetic on expanding the joint capsule in shoulder capsulitis and other large joints 7 anaesthetics may reduce postinjection anaesthetics may also prolong the duration of time the steroid remains within the joint by promoting vasoconstriction and thereby delaying clearance. What size needle should be used? Generally, the smallest needle possible should be used, which is normally a 25-gauge (blue) for most sites. A 22-gauge (green) is preferable for knee joints, or for when aspiration is expected to reveal viscous fluid. Hyaluronic acid Intra-articular hyaluronans are becoming an increasingly used treatment for OA. Hyaluronic acid is a large glycosaminoglycan that occurs naturally within the synovial fluid. Their use in veterinary practice to improve performance in arthritic joints dates back many years. In the USA they were first licensed for human use in 1997, using a regimen of three to five injections at weekly intervals. Following the publication of several randomised trials in the USA there was considerable hope for the use of these products. However, a more recent meta-analysis suggested only a small benefit over placebo perhaps more comparable to the use of NSAIDs. It also raised concerns over the likelihood of publication bias. In summary, because of its increased cost along with the inconvenience of requiring a series of three to five injections, it should be reserved for people in whom other treatment options have failed. Side-effects Side-effects of injecting steroids include skin atrophy at the site of injection, depigmentation and discoloration at the site. Postinjection is a wellreported phenomenon, which is due to steroid crystals forming within the joint. Infection is not common 8 and is estimated at between 1:2000 and 1: procedures. It can sometimes be difficult to differentiate infection and postinjection. Typically, postinjection starts and resolves within 48 hours, whereas infection develops after 48 hours and is associated with systemic features, eg fever, malaise. There is no real evidence to suggest joint injections predispose to Charcot s joints, although there are some anecdotal reports associated with more frequent injections. Systemic glucocorticoid effects have been seen only in patients 52 Prescriber 19 October

3 Injection technique Joint and soft tissue injections should be used in conditions that are clearly demarcated and well diagnosed and in which the injector is comfortable with the procedure. Some general guidance follows: exact location of the needle is not always necessary as even the more experienced injectors can obtain good response rates with periarticular injections 13 it is a clean, not sterile procedure; evidence suggests that, despite wide variation in precaution against sepsis, this is rare 8 anatomical landmarks are important and using them reduces the discomfort of scraping bone a drawing-up needle should be used that is separate from the injecting needle (no touch technique) hours rest is beneficial, especially in weight-bearing joints 15 they should be administered at a maximum of 3 a year as they tend to lose their efficacy over time in noninflammatory conditions receiving injections on a regular basis, ie every month. 9,10 Hypersensitivity to injected steroids can occur and is probably due to the diluent rather than the steroid itself. Common injection areas anatomical approach to specific injection sites Knee joint Painful knee effusions in patients with rheumatic disease are both common and disabling. Aspiration can relieve significant pressure and increase range of movement, while steroid instillation will often produce many months of symptom relief. We recommend using 40mg triamcinolone acetonide Figure 2. The glenohumeral joint is one of the most common sites for injection (Kenalog) combined with 4ml lidocaine. There are multiple approaches that are described for knee joint injection. We recommend a medial approach. Locating the insertion of the tendon of quadriceps femoris into the proximal patella, follow onethird of the way around the medial border of the patella and insert the needle 2cm below this parallel to the horizontal axis (see Figure 1). Shoulder Glenohumeral joint This is one of the commonest places for injection. Pathology in the glenohumeral joint tends to present as a global restriction in internal and external rotation. The classical example is adhesive capsulitis (frozen shoulder). The other main indication is rheumatoid or other inflammatory arthritides. Injecting the glenohumeral joint is easiest using the posterior approach. Tracing the spine of the scapula laterally to the acromial angle, the needle should be inserted approximately 2cm below this mark, pointing towards the coracoid process (see Figure 2). Use 4ml of 2 per cent lidocaine and 40mg triamcinolone acetonide. 54 Prescriber 19 October

4 Subacromial bursa (rotator cuff) Pain is often described over the lateral aspect of the upper arm (over the deltoid). Examination reveals a painful arc, with pain on resisted abduction. This can be due to the impingement syndrome, with inflammation in the subacromial bursa causing restriction of the supraspinatus tendon. It is important to remember that space is limited in the subacromial bursa, and not more than a total of 3ml can be injected. We recommend 1ml of lidocaine and 1ml of triamcinolone. The safest technique uses a lateral approach. The patient should relax their neck and shoulder muscles, sitting up with hands resting in their lap. The injection is placed approximately 2cm below the midpoint of the lateral edge of the acromion the gap between the inferior border of the acromion and the humeral head is usually palpable and is angled towards the opposite humeral head. Wrist We recommend the use of 2ml of lidocaine combined with 40mg of triamcinolone. Position the hand prone and locate the base of the second metacarpal bone. The joint space is palpable between the extensor of the index finger and the thumb abductor. Elbow (epicondylitis) Many patients presenting with elbow pain have inflammation not of the joint but of the periarticular structures. The most common site is the lateral epicondyle (known as tennis elbow ). The aetiology is repetitive wrist movements, resulting in rubbing of the extensor carpi radialis tendons over the lateral epicondyle. Classically (and anecdotally), it occurs in novice tennis players who use a tight grip Figure 3. Injection technique for lateral epicondylitis (tennis elbow) on the racket and have poor technique at backhand. Medial epicondylitis is often referred to as golfer s elbow, again due to presentation in people learning to play golf. There have been some case reports of this condition occurring with the use of fluoroquinolones, possibly through the same mechanism through which Achilles tendonitis occurs. Treatment should initially be with rest and analgesics but, if these fail to control symptoms, a corticosteroid injection is an efficacious option. 11 We recommend using 1ml of local anaesthetic and 25mg hydrocortisone (Hydrocortistab). Lateral epicondyle The patient should sit with the elbow flexed to 90 and, with the forearm supinated (palm upwards), the needle should then be inserted into the area over the epicondyle where there is maximal tenderness (see Figure 3). Medial epicondyle Laying the patient supine, the shoulder should be rotated externally to around 90 and the elbow flexed to 90. The injection is made slightly distal to the centre of the epicondyle. Trochanteric bursa Bursitis is one of the commonest causes of hip pain. Friction occurs between the bursae around the greater trochanter and both the tendon of gluteus medius (which inserts distally into the greater trochanter) and also the tensor fascia lata (running from the anterior superior iliac crest into the iliotibial tract, which in turn attaches to the lateral tibial condyle). The patient will often complain of difficulty walking and of being unable to sleep on the affected side. Examination is usually diagnostic and it is important to exclude underlying hip joint pathology. Initial therapy with analgesics and passive stretching exercises should be tried in the first instance. If these fail, then lidocaine and steroid injection are an effective option. 12 Placing the patient in the lateral decubitus position, with the hip flexed to 90 to allow identification of the superior aspect of the greater trochanter, the point of maximal tenderness should be identified and marked as the site for injection (see Figure 4). There is more than one bursa over the greater trochanter so the exact location of the pain may vary. Figure 4. Injection technique for trochanteric bursa; analgesics and stretching exercises should be tried in the first instance in cases of bursitis Prescriber 19 October

5 Other injections In patients in whom recurrent joint injections into typically large joints are needed more than three times a year, a yttrium 90 isotope injection can be used in specialist centres; alternatively osmium could be used. This is usually reserved for patients with mono- or oligoarthritis. Conclusion In the past many doctors have been reluctant to administer joint injections. This has been due to fears regarding adverse events based on old studies using much larger doses of steroids. More recent data now support the use of joint injections for many conditions, and the techniques involved are both safe and simple. This article aims to increase the knowledge and skills available to the general practitioner, therefore allowing more comprehensive management of rheumatic disease in primary care. Further reading Doherty M. Rheumatology examination and injection techniques. 2nd ed. London: WB Saunders, References 1. Hollander JL, Brown EM Jr, Jessar RA, et al. Hydrocortisone and cortisone injected into arthritic joints: comparative effect of and use of hydrocortisone as a local antiarthritic agent. J Am Med Assoc 1951;147: Ziff M, Scull E, Ford D, et al. Effects in rheumatoid arthritis of hydrocortisone and cortisone injected intra-articularly. AMA Arch Intern Med 1952;90: Bamji AN, Dieppe PA, Haslock DI, et al. What do rheumatologists do? A pilot audit study. Br J Rheumatol 1990;29: Gumpel JM. Intra-articular therapy. In: Scott JT, ed. Copeman s textbook of the rheumatic diseases. 6th ed. Churchill Livingstone, Jones A, Doherty M. Intra-articular corticosteroids are effective in osteoarthritis but there are no clinical predictors of response. Ann Rheum Dis 1996;55: Weitoft T, Uddenfeldt P. Importance of synovial fluid aspiration when injecting intra-articular corticosteroids. Ann Rheum Dis 2000;59: Mulcahy KA, Baxter AD, Oni OO, et al. The value of shoulder distension arthrography with intraarticular injection of steroid and local anaesthetic: a follow-up study. Br J Radiol 1994;67: Pal B, Morris J. Perceived risks of joint infection following intra-articular corticosteroid injections: a survey of rheumatologists. Clin Rheumatol 1999;18: Mader R, Lavi I, Luboshitzky R. Evaluation of the pituitary-adrenal axis function following single intraarticular injection of methylprednisolone. Arthritis Rheum 2005;52: Emkey RD, Lindsay R, Lyssy J, et al. The systemic effect of intraarticular administration of corticosteroid on markers of bone formation and bone resorption in patients with rheumatoid arthritis. Arthritis Rheum 1996;39: Smidt N, van der Windt DA, Assendelft WJ, et al. Corticosteroid injections, physiotherapy, or a wait-andsee policy for lateral epicondylitis: a randomised controlled trial. Lancet 2002;359: Shbeeb MI, O Duffy JD, Michet CJ Jr, et al. Evaluation of glucocorticosteroid injection for the treatment of trochanteric bursitis. J Rheumatol 1996;23: Jones A, Regan M, Ledingham J, et al. Importance of placement of intraarticular steroid injections. BMJ 1993;307: Charalambous CP, Tryfonidis M, Sadiq S, et al. Septic arthritis following intra-articular steroid injection of the knee a survey of current practice regarding antiseptic technique used during intra-articular steroid injection of the knee. Clin Rheumatol 2003;22: Chakravarty K, Pharaoh PD, Scott DG. A randomised controlled study of post injection rest following intra-articular steroid therapy for knee synovitis. Br J Rheumatol 1994;33: Dr Galloway is specialist registrar in rheumatology and Dr Bukhari is consultant rheumatologist in the Department of Rheumatology, University Hospitals of Morecambe Bay, Royal Lancaster Infirmary 56 Prescriber 19 October