Steroid injections, also called corticosteroid injections, are anti-inflammatory medicines used to treat a range of medical conditions. They are also used as a treatment adjunct in the management of various musculoskeletal pathologies.
The injections usually contain a type of steroid medication and a local anaesthetic. Corticosteroids are medications that mimic the effects of the hormone cortisol, produced naturally by the adrenal glands. Cortisol affects many parts of the body, including the immune system.
The purpose of a corticosteroid injection is to reduce the interaction between certain white blood cells (T-cells and B-cells) involved in the immune response. Corticosteroids stimulate this effect to lessen the inflammatory response in certain musculoskeletal conditions where an exaggerated inflammatory process is present.
A steroid injection may take up to a week before you start to notice any benefit. However, you may experience immediate pain relief secondary to the local anaesthetic that was combined with the steroid. Also, you may experience immediate relief if the steroid injection was combined with fluid aspiration.
Depending on the patient and the condition being treated, a successful cortisone injection can suppress localized inflammation for anywhere from 6 weeks to 6 months. Therefore, these effects are short-term treatment options.
Patients who are advised to have repeated steroid injections if the prior resulted in unsatisfactory results, should be aware that the period of pain relief experienced will reduce with increasing steroid injection administration. It should also be noted that this is not necessarily because you have built up a tolerance to the medication, but because the joint is degrading (with time) with conditions such as Rheumatoid Arthritis and Osteoarthritis.
Repeated corticosteroid injections can result in damage to soft tissues including, tendons, ligaments and articular cartilage. Therefore, you are advised to have no more than four injections and should be administered six weeks apart.
Common side effects include:
(Brinks et al., 2010)
It should be noted that steroid injections for soft tissue pathologies – such as tendonitis, should (where possible) be avoided. It is well evidenced in scientific literature that many negative effects occur to the structural make-up of the tendon – essentially, increasing the risk of tendon rupture. Therefore, it is advisable (where possible) to avoid a corticosteroid injection in such pathologies.
In tendonitis, the underlying mechanisms have thought to include limited inflammatory processes (particularly in the long-term) such that this terminology is becoming redundant and being replaced with the term tendinopathy. Therefore, please seek advice from your specialist Physiotherapist. It should also be noted that a steroid injection may have benefits – in some cases, for reducing the initial pain to allow you start a specific exercise protocol, particularly if you have co-exiting pathologies such as arthritis in a joint in the same area as your soft tissue pain (Dean et al., 2014).
Typically the process of administering a cortisone injection will normally take no longer than 20 minutes. Like with any injection, you can experience mild to moderate pain. However, the clinician may administer a topical anaesthetic to the area receiving the injection once thoroughly cleaned.
You will be asked to lie down and keep the area nice and relaxed whilst the injection is administered. If the affected area contains excessive fluid, the clinician may remove this with a needle and syringe; known as aspiration. Often the cortisone is mixed with a local anaesthetic such as lidocaine or bupivacaine to decrease discomfort. These effects may last for a few hours. After the injection has been administered the area will be cleaned once again.
A small amount of bleeding may occur where the needle has pierced the skin, however this may increase if you are on blood thinning medication. Sometimes, the injection can also be administered with the assistance of ultrasound to improve accuracy when positioning the needle tip. You will often be advised to limit heavy loading of the affected structures for at least 48 hours post-injection to protect the area and monitor any potential side effects.
Corticosteroid injections should be used in conjunction with Physiotherapy and not in isolation. The desired pain relief subsequently provides a window of opportunity to treat the underlying cause of your pain with appropriate Physiotherapy interventions to prevent re-occurrence or worsening symptoms. However, if you have a steroid injection without subsequent Physiotherapy, the pain relief will be short-lived and the underlying cause of the pain will still be present, meaning that your pain will most likely re-occur in most musculoskeletal conditions.
Avoid (where possible) having a corticosteroid injection due to the associated risks – particularly for tendon pain, and always ensure that this is followed up with a specialist Physiotherapist to treat the underlying cause with a specific exercise protocol (risk free) as the steroid injection will only treat the symptoms and is associated with negative effects to the articulating surfaces in joints and the structure of tendons.
Brinks, A., Koes, B. W., Volkers, A. C., Verhaar, J. A., & Bierma-Zeinstra, S. M. (2010). Adverse effects of extra-articular corticosteroid injections: a systematic review. BMC musculoskeletal disorders, 11(1), 206.
Dean, B. J. F., Lostis, E., Oakley, T., Rombach, I., Morrey, M. E., & Carr, A. J. (2014, February). The risks and benefits of glucocorticoid treatment for tendinopathy: a systematic review of the effects of local glucocorticoid on tendon. In Seminars in arthritis and rheumatism (Vol. 43, No. 4, pp. 570-576). WB Saunders.
Steroid Injections . (2020, April 30 ). Retrieved from NHS: https://www.nhs.uk/conditions/steroid-injections/