PONOS · ULTRASOUND-GUIDED PROCEDURES
Ultrasound-guided sacroiliac injections
A targeted treatment to relieve pain and provide useful information for planning your diagnostic and treatment pathway.
No X-rays · Outpatient care · At the first consultation when appropriate
A procedure to help understand and treat pain
The sacroiliac joints connect the sacrum to the iliac bones of the pelvis. Pain may arise from the joint, its capsule or the surrounding ligaments. Identifying the structures involved helps guide treatment.
An injection delivers medication to the site identified during the specialist assessment, using ultrasound to guide the needle. Local anaesthetic can provide information about the source of pain; a corticosteroid, when indicated, has a therapeutic anti-inflammatory purpose.
Ultrasound: real-time guidance without radiation
Ultrasound guidance uses sound waves and involves no X-ray exposure. It helps identify anatomical landmarks and guide the needle towards the selected target. The injection can be performed in a suitably equipped outpatient setting using aseptic technique; an operating theatre is not inherently required.
This can simplify arrangements and reduce time and costs. Ultrasound nevertheless has limitations related to depth and individual anatomy and does not always confirm that medication has spread inside the joint. If specific confirmation of intra-articular placement is needed, the specialist may recommend a different imaging method.
Ultrasound in PONOS clinical practice
When is an injection appropriate?
An injection may be considered when the examination suggests that the sacroiliac complex contributes to the pain, particularly when symptoms restrict daily activities or persist despite initial treatment. Not all lower back or buttock pain comes from the sacroiliac joint: spinal, hip, neurological and inflammatory causes must also be considered.
Suspected inflammatory sacroiliitis may require rheumatological assessment. An injection does not replace treatment of the underlying disease.
Preparation: investigations and medication
There is no routine package of tests required for everyone. The need for blood tests or imaging depends on your history, examination, medication and individual risk factors. Bring existing reports and an up-to-date medication list.
Sacroiliac and intra-articular injections, including hip and knee injections, can generally be performed without stopping anticoagulants or antiplatelet medication. Routine interruption is not required for joint injections unless particular circumstances increase bleeding risk. Always tell the specialist what you take and do not change medication yourself.
For epidural injections and radiofrequency procedures, medication management is decided individually. The site and technique, the medication and the balance between bleeding and thrombotic risk all matter. Radiofrequency encompasses procedures with different risk profiles and does not automatically require interruption. If interruption is needed, the timing of stopping and restarting is agreed with the clinicians involved.
Stopping anticoagulants can expose patients to thrombotic complications. An observational study of several pain procedures, including sacroiliac blocks, reported serious complications in the group that stopped anticoagulants and no complications attributed to these drugs in the group that continued them. This supports individual assessment, rather than a claim that every medication and patient carries no risk.
Report allergies, fever or infection, diabetes, clotting problems, pregnancy and previous reactions to injections.
Clinical judgement in the patient’s interests
Providing care means making decisions and accepting clinical responsibility. Every treatment has potential benefits and risks. Withholding care or stopping medication may also have consequences.
At PONOS, we weigh both sides and recommend what is appropriate for the individual, avoiding unnecessary medication interruptions, investigations and delays. Decisions are explained and shared with the patient, focusing on their specific problem and treatment goals.
At the first consultation, when possible
Within the PONOS pathway, if the assessment confirms the indication and the necessary clinical and organisational conditions are met, an ultrasound-guided injection can be performed during the first consultation, without an additional charge for the injection performed at that appointment.
Before proceeding, we explain the aims, limitations, alternatives and possible adverse effects and obtain consent. Performing the injection at the first visit depends on its appropriateness for that person.
The diagnostic value of the response
Before the injection, pain intensity and difficulty with movements that normally provoke symptoms are recorded. After local anaesthetic, the same movements are repeated when safe, assessing reported pain and function over the first minutes and subsequent hours.
Significant improvement consistent with the expected duration of the anaesthetic provides useful diagnostic evidence. The patient’s assessment is central, but the response alone is not absolute proof: spread into neighbouring tissues and other factors can influence the result.
If a corticosteroid is added, its effect is assessed over the following days and distinguished from immediate anaesthetic relief. This is a diagnostic and therapeutic injection rather than a pure local anaesthetic test.
After the injection and number of sessions
Following a short observation period, you receive individual advice on activity and pain monitoring. Recording symptom changes, duration of relief and changes in everyday activities is useful.
A mandatory course of three injections is not appropriate for everyone. Repeating treatment makes sense when the response and clinical course justify it. Little or no benefit calls for reassessment of the diagnosis and target; it does not automatically establish that the pain is mechanical.
Possible adverse effects include temporary local soreness, bruising, a vasovagal reaction and, with corticosteroids, a temporary rise in blood glucose. Infection, significant bleeding and allergic reactions are possible, although uncommon. Fever, rapidly worsening pain, new weakness or other significant symptoms require prompt medical assessment.
When to consider radiofrequency
If pain persists or relief is short-lived, the pathway is reassessed. In selected patients, radiofrequency treatment of the nerves supplying the posterior sacroiliac complex may be an option. Selection may require specific prognostic lateral branch blocks; these are not equivalent to a simple joint injection.
Radiofrequency requires dedicated planning and may use radiological guidance in theatre. The X-ray equipment belongs to this pathway and is not needed for an outpatient ultrasound-guided injection.
Frequently asked questions
Do I need an X-ray or MRI before my consultation?
These are not automatically required for everyone. Bring any existing investigations; further tests are requested according to your clinical presentation.
Should I stop anticoagulants or antiplatelet medication?
Sacroiliac and intra-articular injections can generally be performed without stopping these drugs, except where particular bleeding risk factors apply. For epidural injections and radiofrequency, management is specific to the procedure and patient. Do not change medication yourself.
Must relief occur within one minute?
There is no universal one-minute threshold. The response is assessed over a timescale appropriate to the local anaesthetic used, comparing pain and function before and afterwards.
Is an injection always necessary for diagnosis?
It is an important tool in selected cases, alongside examination and any relevant investigations. It is not compulsory for everyone with lower back or buttock pain.
Selected references
- Uson J et al. EULAR recommendations for intra-articular therapies. Annals of the Rheumatic Diseases. 2021;80:1299–1305.
- Endres S, Shufelt A, Bogduk N. The Risks of Continuing or Discontinuing Anticoagulants for Patients Undergoing Common Interventional Pain Procedures. Pain Medicine. 2017;18:403–409.
- McCormick ZL et al. Consensus practice guidelines on sacroiliac joint complex pain from a multispecialty, international working group. Pain Medicine. 2025;26:817–917.