Hindfoot ‘Triple’ Fusion Surgery

Surgery is performed under general anesthetic as an inpatient. The stay is usually 2-3nights. The procedure takes 2 hours. The aim of surgery is to improve the position of the joints at the back of the foot and stop them moving so removing the pain. The fusion involves 3 joints and so is called a triple fusion.This surgery one of the last resort to correct complex foot deformities.

Technique

The surgery is done with you in a supine position. Two incisions are required on the inside and the outside of the foot , each about 6-8cm long. The affected joints can be seen, and they are prepared by removing any remaining cartilage and drilling the surfaces and realign the bone to correct deformities. Once all three joints are prepared, they are fixed together with screws or plates. It is normally necessary to take bone graft to help with the healing process. This graft is usually taken from iliac crest on the same side as the fusion is taking place. The tissues are stitched and a below knee back slab is then applied while you are still asleep.

Risks

All surgery carries potential risks. This is minimized surgery being pefromed an experienced surgeon.

  • Infection - approximately 2% risk in our unit
  • Blood clots (thrombosis) – You will be put on Low molecular weight Heparin prophylaxis to reduce the risk of blood clots in calf, thigh or rarely in lungs.
  • Numbness – can occur over the outer border and inner border of the foot, and usually improves over time.
  • Pain and swelling - This can occur after any foot and ankle surgery. You have to keep the limb elevated for 48 hours to avoid swelling and you will be given pain killers. Rarely you can develop a special condition called CRPS which can cause long term pain.
  • Stiffness – this improves over time and helped by physiotherapy
  • Scar sensitivity - can be improved with scar massage
  • Pain, swelling, and bruising - will occur to some degree following all foot and ankle surgery
  • Delayed or non-union - the non-union rate (bones not healing together) is approximately 5-10 % and is higher in people who smoke.

Discharge advice following a triple fusion

Dressings

Your leg has been dressed in a plaster back- slab to give it support. This dressing should not be changed until you are seen at your first follow-up appointment after 2 weeks. The plaster must be kept clean and dry.

Elevation

It is very important that you rest as much as possible and keep your foot elevated for the first 48 hours after surgery. Try to avoid letting it hang down when sitting as this will lead to swelling and pain. This is most apparent within the first 2 weeks but swelling may occur for up to 6 months after surgery, especially after sitting or standing for long periods. In bed, put the foot on a pillow.

Analgesia

You will receive a prescription for pain medication on discharge. Pain is often due to swelling, and this is eased by rest and elevation of the foot.

Walking

A physiotherapist will have shown you how to use crutches. You should not put any weight on the foot for at least 6 weeks.

Follow-up

You will be seen approximately 2 weeks when the plaster and sutures will be removed. At this stage a removable boot will be applied. You will be seen again after 6 weeks when you will have an X-ray. If all is progressing well, you will start to take more weight on the foot. You will then be seen 12 weeks after the surgery. The foot will require immobilizing for a total of 12 weeks. The fusion might take from 6-12 months. So you will be seen in pour clinic until the joint is fused.

Driving

You should not drive a manual car for 12 weeks following surgery. After this you should start gradually, to see if you are comfortable. It normally takes a few days to feel confident.

Work

If you have an office-based job, then it may be possible for you to return after 2 weeks however it is more advisable to return after 12 weeks. If you have a more physical job, then it may take 16-20 weeks.

Recovery

It often takes up to 12 months for all swelling to resolve and so minor swelling late in the day is not unusual and should not be a cause for concern.