Achilles Tendon Imaging London | Private Ultrasound Diagnosis & Injections

Achilles Tendon Pain Explained

Achilles Tendon & Calf Anatomy

Insertional Achilles tendinopathy affects the Achilles tendon insertion onto the back of the heel bone (calcaneum).

It is a common source of pain in both sportspeople and the general population.

In this region, the body provides some natural cushioning via:

• Kager’s fat pad (a fat pad deep to the Achilles tendon)

• A fluid-filled sac called the retrocalcaneal bursa, which helps reduce friction between the Achilles tendon and the heel bone

When excessive repetitive forces or loading occur (common in activities such as running, jumping, or hill walking), these structures can become inflamed:

• The Achilles tendon mid-portion may develop degenerative changes and tendinopathy

• The Achilles tendon/ bone interface insertion may develop degenerative changes and tendinopathy (insertional tendinopathy)

• The retrocalcaneal bursa may become swollen and inflamed, contributing to pain and disability

Causes of Achilles Tendon Pain

Achilles tendinopathy typically presents with:

• Pain, thickening and stiffness at the Achilles Tendon mid-portion or the back of the heel

• Pain worsened by walking uphill, stairs, or running

• Swelling at the Achilles Tendon mid-portion or insertion

• Pain when the heel is compressed, such as in certain footwear

Diagnosing Achilles Tendon Pathology

Ultrasound imaging is the diagnostic method of choice:

• It can clearly visualise the Achilles tendon mid-portion, Achilles insertion to the calcaneum, retrocalcaneal bursa, and Kager’s fat pad

• It can detect degenerative changes in the tendon, calcification, or bony spurs

• It can assess for bursal swelling and fluid accumulation

• It can exclude swelling (effusions) to the posterior aspect of the ankle joint

Ultrasound Guided Injections for Achilles Tendon Pain

Achilles Tendon Sheath (Paratenon) Ultrasound Guided Injection

When paratenon inflammation contributes significantly to mid-portion or insertional Achilles tendinopathy, an ultrasound-guided injection into the Achilles paratenon can provide targeted symptom relief while avoiding direct tendon injection.

The ultrasound probe is placed in a longitudinal or transverse plane over the Achilles tendon, allowing visualisation of:

• The Achilles tendon fibres

• The surrounding paratenon and peritendinous space

• Areas of paratenon thickening, hypervascularity, or fluid

• The needle is introduced from the medial aspect of the ankle and advanced under continuous ultrasound guidance into the peritendinous (paratenon) space, remaining clearly extra-tendinous at all times.

• The injectate (local anaesthetic ± corticosteroid) is visualised spreading circumferentially around the tendon within the paratenon, confirming accurate placement without intratendinous infiltration.

This injection may reduce pain and paratenon-related inflammation, helping to facilitate graded Achilles loading and rehabilitation, particularly when pain has limited progression with exercise-based management alone.

Retrocalcaneal Bursa Injections for Insertional Achilles Tendinopathy

When retrocalcaneal bursitis contributes significantly to insertional Achilles tendinopathy, an ultrasound-guided injection into the retrocalcaneal bursa can provide targeted relief.

Injection technique:

The ultrasound probe is placed in a transverse plane above the heel bone, visualising:

Achilles tendon superficially

Retrocalcaneal bursa deep to the tendon

The needle is passed from the medial (inside) aspect of the heel, advancing parallel to the tendon.

The injectate (local anaesthetic + corticosteroid) is visualised flowing into the bursa without resistance.

High Volume Injections for Chronic Achilles Tendinopathy

When mid-portion Achilles tendinopathy has failed to respond to a structured loading programme under physiotherapy supervision, a high-volume (HV) injection may be considered.

Injection technique:

• Under ultrasound guidance, a mixture of local anaesthetic, small volume corticosteroid, and saline is injected around the mid-portion of the Achilles tendon.

• The goal is to pressurise the peritendinous space to:

• Compress and obliterate the small blood vessels (neovascularisation)

• Reduce nerve ingrowth

• Settle local inflammation

What to Do After an Achilles Ultrasound Guided Injection

Needle Path & Post-Injection Pain
Depending on the type of procedure which is administered, there can be some post injection soreness with the volume of steroid, local anesthetic and saline (if a high volume injection is administered) causing a post-injection flare, typically lasting 2–3 days. This is thought to be related to the medication interacting with the local tissues and synovial fluid.

Wound Care & Infection Risk
Avoid exposing the injection site to dirty or public water (e.g., swimming pools, hot tubs) for 2–3 days to reduce infection risk. Monitor for redness, swelling, or discharge at the injection site and contact me immediately if these occur.

Activity Guidance
With any Achilles tendon injection the tendon should be offloaded from any significant activity other than every day walking for two weeks. Sensible graded activity to the tendon with guidance from a rehabilitation professional should be commenced following this two week period.

Follow-Up
If you experience unusual pain, swelling, redness, or any other concerns following your injection, please contact me immediately.

Other Treatments for Achilles Tendon Pain

Stretches for Achilles Tendon Pain

Progressive Soleus Muscle Strengthening for Achilles Tendon Pain

Progressive Gastrocnemius Muscle Strengthening for Achilles Tendon Pain

Achilles Tendinopathy | Evidence base

Achilles tendon pain is most commonly due to tendinopathy, which may involve the mid-portion or insertion of the tendon and is characterised by activity-related pain, stiffness, and impaired load tolerance. The condition typically follows a chronic, non-inflammatory course, and the evidence strongly supports progressive loading and rehabilitation as the cornerstone of management. Injection therapy is not disease-modifying and should be considered adjunctive and selective, primarily to address pain generators that limit rehabilitation. Ultrasound guidance plays a key role in phenotyping symptoms, differentiating tendinopathy from paratenon inflammation, retrocalcaneal bursitis, or partial tearing, and in guiding targeted extra-tendinous interventions. Ultrasound-guided paratenon or peritendinous injections may provide short-term pain relief in selected patients with prominent paratenon thickening or neovascular-associated pain, facilitating engagement with a structured loading program. Intratendinous corticosteroid injection is not recommended due to the risk of tendon weakening and rupture. Overall, ultrasound-guided procedures in Achilles tendon pain are best used to support rehabilitation by addressing associated inflammatory or mechanical pain drivers, with long-term outcomes dependent on well-executed, progressive tendon loading.

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