Questions and answers
Q: What are the side effects of steroid injections?
A: Cortisone injections are a low risk injection; side effects are uncommon but include facial flushing, after injection flare up of pain and vaginal bleeding. These are the most common side effects and are all sort term. They typically last 12-24 hours and onset is about 12 -24 hours after the injection.
Other rare complications include tissue damage including minor changes such as de-pigmentation of the skin and more significant changes such as atrophy (wastage) of fat tissue and damage to tendons. These risks are greatly reduced when the injection is performed under guidance. Accurate needle placement ensures the needle never enters tendon or fat tissue.
The positive effects of a steroid injection are realised when the injection is placed into the joint cavity, inside the bursa and directly in the the tendon sheath which surrounds the tendon. These are millimetres in size, which is why ultrasound guidance is essential.
Q: How painful is the injection?
A: the pain experience varies from person to person. The thought of an injection is nearly always more worrying than the injection itself. Different areas of the body are also more sensitive and the reason for the injection can affect the pain experience. For example, by using an injection solution to inflate a joint capsule (hydro-dilitation) we are generating a strong capsular stretch along side the anti-inflammatory medication. This can be more painful than a simple knee or hip injection where we are just depositing the medication. A key factor in the overall experience is governed by the patients confidence. If the person can see the inflamed tissue and knows (can watch if they want) that the needle is being guided to the exact spot, then confidence is improved and the overall experience is less concerning.
Q: How long does it take for a steroid injection to work?
A: Steroids take 3-10 days to reach maximum effect and have a half life of 5 weeks. This means that a typical dose of 40 mg will be reduced to 20 mg by the end of 5 weeks. After 10 weeks the drug will have a value of 10 mg and so on. For most peolpe the real anti-inflammatory benefit will therefore last around 15 weeks. After that the dosage is low and the effect will be minimal. However, this does not mean your pain experience will return. If you have combined your injection with appropriate corrections to movement and strengthening, your joint may stay calm for an much longer period of time.
Q: Can I drive after an injection?
A: 99% of the time ‘yes’. There is however the odd occasion when a person feels light headed or anxious. If in any doubt please ask someone to accompany you; but overall, based on my personal experience from injecting thousands of different people for many different conditions, they all drive home safely.
Q: What can I expect after a cortisone shot?
A: If a local anaesthetic has been included in the injection solution then there may be quite immediate pain relief. The main benefit of the steroid will however begin to work in 3-10 days. A decrease in inflammation alters the tissue chemistry, which in turn decreases the initiation of a pain response. Remember that a pain impulse is generated by chemical and mechanical changes. When you change the chemistry and decrease inflammation and you will decrease the pain. Correct the mechanics of the joint and you will make further and longer lasting improvements. Please remember that there are no cures, but there are medical related interventions that optimise any individuals health. Best chemistry and best mechanical joint function will always minimise the likelihood generating a pain response. Conversely, weakness and poor joint function coupled with excessive inflammation and altered body chemistry (which is also influenced by our state of mind!) will always trigger pain. Therefore it is important to purse your best health, understand how and why pain exists and always strive to control pain related emotions; they really don’t help.