1st MTPJ (Big Toe) Fusion: The Key Components
Written by:
Orthopaedic surgeon
Published: 08/02/2023
Edited by: Aoife Maguire
What is MTPJ (Big Toe) Fusion?
Hallux Metatarsophalangeal Joint Fusion (MTPJ fusion) is an operation intended to fuse the big toe joint together. It is also often referred to as an arthrodesis of the big toe (metatarsophalangeal) joint.
What is the purpose of the operation?
This operation aims to fuse the big toe joint together and it is usually performed as a day case operation. It is also referred to as arthrodesis of the big toe (metatarsophalangeal) joint.
It is usually performed to aid painful arthritis of this joint (hallux rigidus) which has not responded to other non-operative treatment.
For certain patients, it may also be recommended for the treatment of a bunions.
What does the surgery involve?
The surgery involves removal of the joint surfaces via an incision over the inside surface of the foot. The two ‘raw’ bone surfaces are then compressed together using titanium screws and a plate to stabilise the joint in the desired position.
This metalwork does not usually need to be removed but it is possible. Holding the prepared joint still permits the bone to knit up across the joint as if healing a broken bone. This is called fusion.
After it is fused, the big toe does not move except at the end (interphalangeal) joint. This should significantly improve the painful symptoms. The toe is positioned for optimal function.
Following successful fusion, you will be able to wear most shoes but not uually those which hace a high heel bigger than 2 inches/5 cm. Furthermore, exercise activities allowed subsequently are unrestricted. The operation is performed under general anaesthetic or regional anaesthetic.
Post operative care
This surgery is beneficial because you are able to walk on the foot immediately after the surgery (day of surgery). There are some rules you must follow after surgery. These are as follows:
You must wear your surgical shoe (post-op shoe) at all times, including in bed at night. Strict elevation of the foot is essential- you should elevate the foot for 50 minutes every hour for one week after the operation. You should take pain medication for the first 2 days regularly. However there is usually very little pain, if any. You may not walk on the foot without this shoe at all, even in the house You may not drive after the surgery for six weeks unless you have an automatic vehicle and only the left foot has undergone surgery. The surgical shoe must be worn for 6-8 weeks.
The foot will probably be numb for 12-24 hours. Some blood drainage through bandage may occur, however, you should not change the bandage.
A follow up review will usually be carried out by the orthopaedic surgeon 10-14 days after surgery.
During the 2-6 weeks following surgery, use of the post-operative shoe should be continual and walking activity should be minimal.
Another follow up review with the orthopaedic surgeon will take place between 6-8 weeks after surgery.
Regarding activity, you cannot play sports or wear high heels until 3 months after surgery. Swelling will continue but slowly improve until 4-6 months post operation.
What are the main risks of big toe fusion surgery?
Swelling
Initially the foot will be very swollen and will require elevation. Swelling will persist for around 4-6 months after surgery. However, in some cases, it will continue up until a year after surgery.
Infection
There is a small risk of infection following surgery, however this risk is extremely low. Keeping the foot elevated for the first 14 days following surgery will reduce the risk of infection.
It is important to contact the surgeon if you are concerned that you may have developed an infection. Signs of infection include increased swelling, redness, heat and/or any discharge in the surgical area.
Wound problems
Sometimes wounds can be slower to heal, which should be monitored for any infection.
Scar sensitivity
Scars may be sensitive following surgery but the problema is normally resolved without treatment.
Nerve Injury
Risk of small nerve damage in surgery is very low. However, the nerves can become bruised by the surgery, due to swelling.
This swelling normally heals, however, permanent numbness in the big toe area may occur, which will lead to irritation.
CRPS – Complex regional pain syndrome
This rarely occurs in a severe form. CRPS can cause swelling, sensitivity of the skin, stiffness and pain. It can be treated but in severe form, it can take many months to recover.
Delayed and non- union
Delayed union is a term used to describe when the bones are slow to heal. Generally, if the bones have not healed on an x-ray by three months then this is a delayed union - and often accompanied by persisting swelling in the foot.
Non-union is used to describe failure of the bones to heal. At times, this may only appear a year following surgery. It is only a problem if there is swelling and discomfort that requires further surgery.
Malposition
Ideally the toe is fused in a position that permits optimum function and the best appearance. Surgeons try to fuse the joint in the best position, although sometimes during surgery, it is not always possible to achieve the best position to fuse the joint.
The toe may be either too high or too low for example. It doesn¡t usually cause a issue which requires further surgery and can be accommodated with insoles.
Deep Vein Thrombosis (DVT)
Deep vein thrombosis is a clot which appears in the deep veins of the leg. The risk of this developing after foot and ankle surgery is low.
However, if it does develop, treatment with heparin and Warfarin will be necessary to prevent the clot travelling to the lungs.