What is a shoulder steroid injection?
For most shoulder & elbow surgeons a “ shoulder steroid injection” means a combined single injection of steroid and local anaesthetic. There are two commonly used steroids for musculoskeletal injections in the UK; methylprednisolone (Depo-medrol) and triamcinolone (Kenalog). I prefer to use triamcinolone in my injections as it tends to have a longer lasting effect. The local anaesthetic used in combination with the steroid depends on the area being injected. I tend to use low concentrations of local anaesthetic when injecting the glenohumeral (shoulder) joint in order to protect the articular cartilage.
What are steroid injections used for in the shoulder or elbow?
The use of steroids around any joint should be limited to the control of pain through reducing inflammation. Sometimes steroid injections can be used to treat conditions (therapeutic) or can help to confirm the source of pain in or around the shoulder (diagnostic), most of the time they do both.
Around the shoulder there are 4 conditions that I commonly recommend steroid injections for; frozen shoulder, acromioclavicular joint (ACJ) arthritis, subacromial shoulder pain, and tenosynovitis of the long head of biceps (LHB) tendon. For subacromial pain steroids are used to help control pain in order to allow the patient to do their physiotherapy exercises which is the key treatment for this condition. I give most steroid injection in the clinic after consultation and confirmation of the diagnosis, however, LHB injections are best performed under ultrasound guidance.
Around the elbow I very rarely use steroid injections. Steroid injections used to be commonly used to treat tennis elbow, but we now know from several research studies that steroid injections can give good pain relief for about 6 weeks, however pain can return, and patients can be worse off than if they had no treatment at all. I do not recommend steroid injections for tennis elbow.
How painful is a steroid injection and can I drive afterwards?
Steroid injections will sting for about a minute and most patients don’t find them that painful in and around the shoulder. It is the local anaesthetic component that causes the stinging sensation. Once the stinging goes away, the local anaesthetic pain-relieving effect kicks in so that patients often have rapid pain relief. It is safe to drive after a steroid injection around the shoulder.
How long do steroid injections last?
The local anaesthetic effect of the injection wears off after a few hours and pain will recur. Steroids themselves take about 2-3 days to kick in so there is usually a gradual reduction in symptoms in the early days following a steroid injection. The duration of the effect of steroids is difficult to predict. Some injections may last weeks or months while others only last days. It is a common observation that the more steroid injections you have the less effective and shorter their duration is.
What are the risks of a steroid injection?
The most commonly observed side effect of a steroid injection into a joint is steroid flare where the joint becomes painful and irritated by the injection. Other rarer side effects include skin or fat atrophy (scarring), depigmentation, and VERY rarely but importantly steroid injections can cause joint infection.
In diabetics, steroid injections can cause a rise in blood glucose readings which can last for a couple weeks after the injection.