Prognostic Injections

Everything you’d like to know about having the Prognostic Injection procedure to manage your pain.

Interventus Pain Specialists conducts Prognostic Injections to help manage a range of persistent pain issues in our patients. Find out about how the procedure is performed, the benefits and risks, and what you can expect when you come to hospital.

Why do I need a prognostic injection?

Broadly speaking, spinal pain can originate from front-of-spine structures, such as the intervertebral discs, or back-of-spine structures, such as the facet joints or sacroiliac joints. Muscular dysfunction can also cause or exacerbate spinal pain.

Prognostic injections help to determine if you are likely to benefit from Radiofrequency neurotomy (RFN). RFN has been well researched and is established as the most effective treatment for facet joint pain that has failed to respond to other measures. Prognostic injections help determine if you are likely to benefit from RFN.

The general success rate for RFN in patients with probable facet joint pain is about 50%, but if your pain improves significantly after a prognostic injection, you are more likely to benefit from RFN.

It is important to remember that the purpose of the prognostic injection is only to establish your potential suitability for RFN. Because it involves the injection of just a local anaesthetic, it is only expected to provide relief for a few hours.

How is the procedure performed?

• An anaesthetist will be present during your procedure to ensure you feel as comfortable as possible
• You will be comfortably positioned lying face down with pillow supports under your legs and chest
• Before the procedure starts, a small needle (cannula) will be inserted into your hand or arm so that sedation can be administered as necessary
• Your back will be cleaned with antiseptic solution and then covered with sterile drapes
• Local anaesthetic will be injected to make the skin area numb and you may feel a sharp sting
• An X-ray machine is used to help guide the needle and when your Interventus Pain Specialist is happy with the location of the needle, a small solution of local anaesthetic will be injected

Are there any risks?

All medical procedures carry a risk of side effects and possible complications.

Common risks and complications for prognostic injections include:

• Bleeding or bruising
• Backache due to the muscle being aggravated by the needle
• Temporary leg or arm weakness due to local anaesthetic
• Temporary nerve irritation due to the volume of fluid injected

Less common risks and complications include:

• Not able to perform the procedure due to medical and/or technical reasons
• Infection requiring further medical treatment
• Allergies
• Damage to surrounding structures that may need further treatment

How do I prepare for my procedure?

At least two weeks before your procedure, inform your Interventus Pain Specialist if you:

• Are taking blood thinners, including fish oils or aspirin
• Are diabetic
• May possibly be pregnant
• Are allergic to iodine, betadine, chlorhexadine, shellfish, local anaesthetics or steroids
• Have a temperature, feel unwell or possibly have an infection

You must have a responsible adult (over the age of 18) collect you after the procedure and stay with you overnight. You must not drive a vehicle or make important decisions for 24 hours following your procedure.

It’s important that you do normal activity following the procedure, in particular the activities that generally make your pain worse. This helps us assess the effectiveness of the procedure in reducing your pain.

What happens on the day of my procedure?

• Please have no food within 6 hours prior to your procedure
• You may drink water up to 2 hours prior to your procedure, but no more that 200mls per hour
• Take your regular medication with a small sip of water
• Shower the morning of your procedure

What do I need to look out for after discharge from hospital?

If you notice any of the following once you return home, please contact Interventus Pain Specialists during office hours, your GP or present to your nearest Emergency Department:

• Swelling
• Bleeding from the injection site
• Changes in sensation
• Difficulty moving your arms or legs
• Any new symptoms
• Difficulty passing urine

What happens next?

• You will be contacted by the Interventus Pain Nurse in the days following your procedure to assess if the prognostic blocks were effective
• You will be asked about your pain score before and after the procedure, and about your pain associated with activity on the day of your procedure