Why ultrasound guidance matters
The foot is small and crowded. Nerves, blood vessels, tendons and the protective fat pads under the heel and ball of the foot all sit close together. Ultrasound lets us:
- See the problem first, such as a thickened plantar fascia, an inflamed bursa, a neuroma or fluid in a joint, which also confirms the diagnosis before anything is injected
- Watch the needle in real time, so the medication goes exactly where it’s needed
- Avoid structures that shouldn’t be injected, such as tendons, nerves and the heel fat pad
- Use the smallest effective dose, because accurate placement means less medication is wasted in the surrounding tissue
What is a corticosteroid injection?
Corticosteroid (often called cortisone) is a strong anti-inflammatory medication. It’s injected together with a local anaesthetic into or around an inflamed bursa, joint, nerve or tendon sheath. The local anaesthetic gives short-term relief, and the corticosteroid usually starts to work over the following days.
Conditions we use it for
- Plantar fasciitis and heel pain that hasn’t settled with other treatment
- Morton’s neuroma, injected around the thickened nerve
- Bursitis, including at the back of the heel, under the heel and over a bunion
- Arthritis and joint inflammation, including big toe arthritis (hallux rigidus) and midfoot arthritis
- Capsulitis and inflammation in the toe joints that contributes to ball-of-foot pain
- Tendon sheath inflammation, such as around the peroneal tendons, injected into the sheath and not the tendon itself
- Tarsal tunnel syndrome, injected around the nerve to reduce swelling in the tunnel
- Sesamoiditis, where inflammation around the sesamoid bones is contributing
Where we don’t use corticosteroid
Corticosteroid can weaken tendons and ligaments, so we don’t inject it:
- Into the Achilles tendon or other major tendons
- Around the tibialis posterior tendon
- Into a toe joint with a plantar plate tear
For these problems, we use other treatments, such as loading programs, shockwave therapy or prolotherapy.
How well does it work?
Corticosteroid injections can give useful short to medium-term relief from pain and inflammation, which often makes it easier to progress with exercises, orthotics and footwear changes. How much relief you get, and for how long, varies from person to person, and some people get little benefit. An injection treats inflammation, not the underlying cause, so it works best as one part of a wider plan.
How many injections can I have?
We use injections selectively. As a general rule, we leave at least 6 weeks between injections and avoid more than 3 injections in the same area within 12 months, because repeated injections increase the risk of side effects.
Possible side effects and risks
Most people have no problems, but your podiatrist will go through the risks with you before the injection, including:
- Post-injection flare: increased pain for a day or two, which usually settles with rest, ice and paracetamol
- Raised blood sugar: in people with diabetes, blood sugar can rise for a few days, so check it more often
- Skin changes: thinning or lightening of the skin at the injection site
- Fat pad thinning: loss of the cushioning fat under the heel or ball of the foot, which ultrasound guidance helps to avoid
- Weakening or tearing of tissue: such as the plantar fascia, particularly after repeated injections
- Facial flushing: for a day or two
- Infection: rare, but seek prompt care if the area becomes increasingly hot, red, swollen or painful after 48 hours, or you feel unwell
Who shouldn’t have one
A corticosteroid injection may not be suitable if you have an infection in the area or elsewhere in your body, poorly controlled diabetes, an allergy to any of the ingredients, a recent live vaccine, or you’re pregnant or breastfeeding. Tell us about any blood-thinning medication, as this affects bruising. We’ll check your medical history and medications before every injection.
What is prolotherapy?
Prolotherapy (short for "proliferative therapy") involves injecting a sugar solution, called dextrose, usually mixed with local anaesthetic, into or around a damaged tendon, ligament or fascia. Rather than switching inflammation off, as corticosteroid does, prolotherapy aims to trigger a mild healing response in tissue that has stalled, and to encourage repair.
Conditions we use it for
- Long-standing plantar fasciitis
- Achilles tendinopathy, alongside a loading program
- Other chronic tendon and ligament problems, where other treatment hasn’t helped
Because dextrose doesn’t weaken tendons, prolotherapy can be used in areas where we avoid corticosteroid. It’s also an option for people who’d rather not have corticosteroid, or who have already had one.
What does the evidence say?
Research on prolotherapy is still developing. A 2023 review of clinical trials in chronic plantar fasciitis found that dextrose prolotherapy improved pain and function over the following 1 to 3 months compared with placebo or exercise alone, with results similar to corticosteroid and PRP injections. In Achilles tendinopathy, an Australian trial found that adding prolotherapy to an eccentric loading program sped up improvement. Most studies are small, so we’ll talk through whether it’s a sensible option for you.
What does a course involve?
Prolotherapy is usually given as a short course of injections, typically spaced 2 to 4 weeks apart. Your podiatrist will recommend a plan based on your condition and how you respond.
What to expect afterwards
Because prolotherapy works by creating a short healing response, the area is commonly sore and stiff for 2 to 3 days. Paracetamol and ice can help. We usually advise avoiding anti-inflammatory medication, such as ibuprofen, for a few days after each injection, as it may dampen the response.
What to expect at your appointment
- Assessment and diagnosis. We confirm the diagnosis, review your treatment so far and check that an injection is the right next step. Ultrasound helps confirm what’s going on.
- Consent. We explain the injection, the expected benefits and the risks, and answer your questions.
- The injection. The skin is cleaned, and under ultrasound guidance the needle is guided to the target. Most injections take only a few minutes.
- Aftercare. Rest the area for 2 to 3 days, avoid aggravating activities, then return gradually to activity. You may prefer not to drive straight after a foot injection, so bring someone if you can.
- Review. We review you to check your progress and continue your rehabilitation, orthotics or footwear plan.
Watch Dr Ozan Amir explain
Injection Therapy for Long-standing Neuroma
Ultrasound-Guided Injection Therapy FAQs
Most people feel a sharp scratch and some pressure. The local anaesthetic numbs the area quickly. Some areas, such as the heel, can be more uncomfortable, and we’ll talk you through it.
The local anaesthetic gives relief within minutes, but this wears off within hours. A corticosteroid usually starts working over a few days to a couple of weeks. Prolotherapy works more gradually, often over several weeks.
It depends on the problem. Corticosteroid is best suited to inflammation in a bursa, joint, nerve or tendon sheath. Prolotherapy is suited to long-standing tendon, ligament and fascia problems, including some where corticosteroid isn’t safe. Your podiatrist will recommend the most suitable option.
Often, yes, but your blood sugar can rise for a few days afterwards, so monitor it more closely. If your diabetes isn’t well controlled, an injection may not be suitable, and prolotherapy or other treatments may be considered.
Rest the area for 2 to 3 days, then gradually return to activity. Your podiatrist will tell you when to restart your exercise program.
No, you can book directly. If your appointment is through a Medicare care plan, DVA or another funded program, you’ll need a referral, so check with us when you book.
Your consultation is covered under extras if your policy includes podiatry. Cover for the injection itself varies between funds, so check with your fund. We’ll give you the item numbers.
Serving Manly and the Northern Beaches.
Manly Foot Clinic is at Shop 3/3 Corrie Rd, North Manly NSW 2100. We see patients from Manly, Balgowlah, Freshwater, Dee Why and Brookvale through to Mosman, Neutral Bay, Chatswood and the wider North Shore.