Overview
A sacroiliac joint injection is a targeted treatment used when the sacroiliac joint is suspected to be a source of pelvic or lower back pain. The sacroiliac joints sit at the base of the spine and transfer weight between the upper body and the legs. When these joints become irritated or inflamed, pain may develop in the lower back, buttocks, groin, or pelvic region.
Symptoms often worsen with standing, walking, climbing stairs, or prolonged sitting. Sacroiliac joint pain may occur after injury, degenerative joint changes, or pregnancy related pelvic instability.
A sacroiliac joint injection delivers medication into or around the joint to reduce inflammation and improve comfort. The procedure can also help confirm the sacroiliac joint as the source of pain if symptoms improve after treatment.
Who this treatment helps
Sacroiliac joint injections may be considered for people with:
- Persistent pelvic, buttock, or lower back pain
- Pain that worsens with standing, walking, or climbing stairs
- Pelvic instability or pain following pregnancy
- Discomfort linked to injury or degenerative joint changes
- Limited improvement with physiotherapy or medication
- Clinical examination suggesting sacroiliac joint involvement
A consultation is required to confirm suitability and ensure the sacroiliac joint is the most likely source of symptoms.
What is a sacroiliac joint injection
A sacroiliac joint injection is a minimally invasive procedure where medication is delivered directly into or around the sacroiliac joint.
The injection typically includes:
- Local anaesthetic to provide temporary numbing
- Steroid medication to reduce joint inflammation
Imaging guidance, usually X ray or ultrasound, is used to ensure accurate placement of the needle. The aim is to reduce inflammation, ease pain, improve movement, and help guide further treatment decisions.
What to expect during the procedure
Your consultant will confirm the treatment plan and answer any questions before the procedure begins.
- You lie comfortably on the procedure table
- The skin over the lower back is cleaned and numbed with local anaesthetic
- A fine needle is guided into position using imaging guidance
- Medication is delivered into or around the sacroiliac joint
- You are monitored briefly before returning home
The procedure is usually performed as a day case and typically takes around 10 to 20 minutes.
After the procedure
It is normal to experience mild soreness or bruising at the injection site. Some people notice immediate improvement due to the local anaesthetic, while others experience gradual improvement over several days as the steroid begins to work.
Your consultant may advise:
- Avoiding strenuous activity for 24 to 48 hours
- Returning to normal activity as comfort allows
- Continuing physiotherapy to support pelvic stability
- Monitoring symptoms and reporting any concerns
Benefits
- May reduce pelvic, buttock, and lower back pain
- Minimally invasive with short recovery time
- Useful as both a diagnostic and therapeutic treatment
- Can improve mobility and daily function
- May reduce reliance on pain medication
- Supports physiotherapy and pelvic stability rehabilitation
Possible risks and side effects
Sacroiliac joint injections are generally safe when performed by experienced clinicians, although some risks may occur.
- Temporary increase in pain
- Local bruising or soreness
- Temporary leg numbness in some cases
- Infection, which is rare
- Bleeding
- Allergic reaction to medication, uncommon
- Very rare irritation of nearby nerves
When to consider other options
If pain does not improve or if symptoms suggest another cause, your consultant may discuss other treatments such as caudal epidural injection, pudendal nerve block, ganglion impar block, or a combined rehabilitation approach.
Safety note
Please inform your consultant about all medications and medical conditions, including blood thinning medication, diabetes, allergies, pregnancy, or recent infection. If numbness persists after the injection you should avoid driving until it fully settles.
Arrange a consultation to discuss whether a sacroiliac joint injection may help relieve your pelvic or lower back pain.
You can also explore our pelvic pain treatments, view all pain treatments, or learn more about our pain management services.