HomeSurgery guidesSubtalar joint fusion (arthrodesis)
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Subtalar joint fusion (arthrodesis)

The subtalar joint sits just below the ankle joint and is responsible for side-to-side foot motion. Subtalar arthritis, often following a calcaneus fracture or from inflammatory arthritis, can be very painful. Fusion of the joint reliably eliminates pain, at the cost of permanently losing the side-to-side ankle motion.

Before surgery
The day of surgery
In hospital
Going home
Recovery week by week

Step 1: Your pre-operative assessment

ℹ️ This appointment takes place 2-4 weeks before surgery. Subtalar fusion is a moderately complex procedure, so the assessment is thorough.

You will meet the nursing and anaesthetic teams. A full review is carried out including a careful explanation of which functions you will lose and which you will retain.

What will happen at the pre-assessment?

Blood tests, ECG, and chest X-ray

Full pre-operative screen.

Medication review

Blood thinners, anti-inflammatory drugs, and steroids may need adjustment.

Anaesthetic discussion

Usually under general or spinal anaesthesia, with a popliteal nerve block for post-operative pain relief.

Smoking

Smoking significantly increases the risk of non-union (the fusion failing to heal). Stop smoking for at least 6 weeks before surgery.

Prepare your home

You will be non-weight-bearing for 6 weeks. Arrange ground-floor sleeping and home help.

The day of surgery

ℹ️ You will be given a specific arrival time. Do not eat or drink (other than clear water up to 2 hours before) from midnight the night before. Bring your medication list and any documents sent by the hospital.

Arrive at the time given

You will be admitted to the ward or day surgery unit, change into a gown, and be seen by the nursing, anaesthetic, and surgical teams before theatre.

Consent and marking

Your surgeon will confirm the procedure, mark the operative side, and you will sign a consent form before going to theatre.

Anaesthetic

You will meet the anaesthetist in the anaesthetic room. Once anaesthesia is established, the procedure will begin.

Recovery room

After surgery you will wake in the recovery room where nurses monitor your vital signs until you are stable and comfortable.

In hospital

Most foot and ankle surgery is performed as a day case, meaning you go home the same day. More complex procedures such as ankle replacement or flat foot reconstruction usually require 1-3 nights in hospital. Before discharge, the team will check your pain is controlled, give you wound care instructions, and confirm your follow-up appointment.

Pain control

You will be given oral pain relief before discharge. Take it regularly for the first 48 hours rather than waiting until pain is severe.

Wound check and dressing

A nurse will check the wound before you leave and explain how to keep it clean and dry.

Crutches and weight-bearing instructions

You will be shown how to use crutches and given clear instructions about weight-bearing on your operated foot.

Discharge letter and follow-up

You will receive a letter for your GP and details of your next outpatient appointment, usually at 2 weeks for a wound check.

You must not drive yourself home

Arrange for a family member or friend to collect you. You must not drive after a general anaesthetic or sedation.

Going home

⚠️ Important: Non-union (failure of the bones to fuse) occurs in around 5-10% of cases, and is significantly more likely in smokers, diabetics, and those who weight-bear early. Smoking cessation is one of the most important things you can do for a successful outcome.

Elevate your foot

Keep the foot elevated above the level of your heart for as much of the day as possible during the first 2 weeks. This significantly reduces swelling and helps healing.

Keep the wound clean and dry

Avoid getting the wound wet until it is fully healed, usually 10-14 days. Use a waterproof cover when showering.

Take your pain relief as prescribed

Do not wait until pain is severe before taking medication. Regular simple analgesia (paracetamol, ibuprofen if appropriate) is more effective than taking it only when needed.

Attend your wound check appointment

This is usually 2 weeks after surgery. Sutures or clips will be removed if used.

When to contact the hospital

Seek urgent advice if you develop increasing redness, warmth, swelling, discharge from the wound, calf pain or swelling (possible DVT), shortness of breath, or a temperature above 38°C.

Recovery week by week

Weeks 0-2

Below-knee cast, non-weight-bearing

Foot kept elevated. Crutches required.

Weeks 2-6

Cast change, continued non-weight-bearing

Wound check, replaced cast. Strict non-weight-bearing continues.

Weeks 6-12

Walking boot, progressive weight-bearing

X-rays confirm bone fusion is progressing. Gradual transition from partial to full weight-bearing in a boot.

3-6 months

Out of boot, normal walking

Transition to supportive shoes. Most patients walking comfortably.

6-9 months

Final recovery

Continuing improvement. Final outcome assessed at 9-12 months.

Common questions

Will I be able to walk on uneven ground?

Yes, but with more difficulty than before, as the side-to-side motion of the foot is lost. The mid-foot joints compensate to some degree.

When can I drive?

For right-sided surgery, around 10-12 weeks. Left side in an automatic, around 6-8 weeks once out of the boot.

How long off work?

Desk work: 4-8 weeks. Standing work: 4-6 months. Heavy manual work: longer.

What if the bones do not fuse?

In 5-10% of cases, non-union occurs. Further surgery may be needed. Smoking is the strongest risk factor.

Common questions

Your questions, answered

Plain-English answers to the things people most often ask, grounded in published guidance. Tap a question to open it.

Your operationWhich joint is fused, and why?

The subtalar joint, which sits just below the ankle and controls side-to-side movement of the foot, is fused with screws. It is done for painful arthritis or deformity of that joint.

Stopping movement at the worn joint is what relieves the pain.

Sources  BOFAS
WellbeingHow will it affect my movement?

The up-and-down movement of the ankle is kept. The side-to-side movement of the hindfoot is reduced, which most people adapt to well and walk comfortably.

Uneven ground can feel different at first.

Sources  BOFAS
AnaesthesiaWhat anaesthetic is used?

Usually a general or spinal anaesthetic with a nerve block for pain relief.

Your anaesthetist will discuss the options.

Sources  NHS
Getting backWhat is the recovery timeline?

There is usually a period of limited or no weight-bearing for some weeks while the bone unites, then a gradual return over several months.

Your team will guide each stage.

Sources  BOFAS
PreparingHow should I prepare?

Plan for a spell off the foot, arrange home help, and have crutches or a frame ready. If you smoke, stopping improves the chance of the bone uniting.

Preparing the home in advance makes the early weeks easier.

Sources  NHS · BOFAS
UrgentWhat warning signs need review?

Increasing pain, wound discharge or a temperature can signal infection, and calf or chest symptoms can signal a clot.

Seek prompt help if these occur.

Sources  NHS
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