Midfoot Fusion

​What is the midfoot?

The midfoot refers to the bones and joints that make up the arch and connect the forefoot (which includes the bones of the toes) to the hindfoot (which includes the ankle bone and the heel bone).
 

What is a midfoot fusion?  

Midfoot fusion is a procedure in which the separate bones that make up the arch of the foot are fused into a single mass of bone. Fusion is also referred to as arthrodesis. Fusion eliminates the normal motion that occurs between two bones.
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At left, this standing X-ray view of a right foot shows a gap between the first and second metatarsals (arrow). At right, this side X-ray view of the same foot shows loss of alignment. In a healthy foot, the two yellow lines would overlap one another.

  
 
Midfoot fusion can involve all of the midfoot joints. More commonly just one or a few of the joints are fused. The joints of the midfoot do not bend and move like your knee or elbow. They are designed to be relatively stiff to give your foot strength and support your body. Midfoot fusion does not generally produce much noticeable loss of motion because there is fairly little motion to begin with.  
 

What are the goals of a midfoot fusion?

The primary goal of midfoot fusion is to decrease pain and improve function. Eliminating the painful motion between arthritic joint surfaces and restoring the bones to their normal positions achieves this. Other goals include the correction of deformity and the return of stability to the arch of the foot. A successful midfoot fusion can achieve these goals and restore more normal walking ability.
 

What signs indicate a midfoot fusion may be needed?

The most common reason for midfoot fusion is painful arthritis in the midfoot joints that has not improved with nonsurgical treatment. Other common reasons to do a midfoot fusion include too much motion of one or more of the midfoot joints or deformity of the midfoot. Examples of conditions that may result in midfoot deformity include severe bunions and flatfoot deformity. Midfoot fusion is also indicated for certain acute fractures and joint displacement involving the midfoot. 
 

When should I avoid surgery?

Midfoot fusion should not be performed if there is active infection or if the patient’s health is poor enough that the risk of surgery is too high. Conditions such as uncontrolled diabetes and blood flow problems may make a patient a poor candidate for surgery. Other reasons to not perform midfoot fusion include osteoporosis and poor skin quality. Smoking significantly increases the risk that bones will not fuse.
 

General Details of Procedure

Successful midfoot fusion depends on complete removal of all joint surfaces (cartilage) and stable fixation of the joints being fused. Residual cartilage can prevent the bones from fusing together. Failure to achieve adequate stability may allow too

  

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Post
-surgery X-rays showing correction. The arrow shows that the gap has been eliminated, and a single line can be drawn through the middle of the foot bones, which means the foot is now in the proper position. Screws and plates were used for the repair.

  much motion for fusion to occur. 
 

Specific Techniques

Midfoot fusion is generally accomplished using one or two incisions on the top of the foot. The length of the incision and how many incisions are necessary is determined by the number of joints to be fused. Careful attention is paid to protecting tendons and nerves.
 
Stability is achieved during midfoot fusion using metal implants such as screws and plates. These are designed to immobilize the joints and allow for the formation of bone across the joint space. This process may involve the addition of bone graft material to fill any gaps that might exist between the bones after the cartilage has been removed. This bone graft material may be taken from another location in the patient’s body (autograft). It may also come from donated bone (allograft) or from a synthetic material. A combination of these materials may be used. 
 

What happens after surgery?

After surgery a period of protection and immobilization is required for successful fusion to occur. A cast is typically placed for the first six to 10 weeks. Weightbearing is not allowed on the affected foot for eight to 12 weeks after surgery. X-rays are usually obtained every four weeks to assess progress of the fusion.
 
Gradually increased weightbearing is allowed as healing progresses. Initial weightbearing is protected in a prefabricated boot with gradual transition to supportive shoes. Physical therapy may be prescribed on a case-by-case basis to help the patient’s walking and balance. 
 

Potential Complications

There are complications that relate to surgery in general. These include risks associated with anesthesia, infection, damage to nerves and blood vessels, and bleeding or blood clots.
 
A major potential complication after midfoot fusion is failure of the bones to fuse (nonunion). Other complications can include over-correction or under-correction of deformity (malunion). There can be problems with wound healing. Prominent plates and screws can be painful and may require removal of the hardware. Injury to nerves on the top of the foot can occur.
 
Smoking is one of the leading risks for nonunion. Premature weightbearing can also result in failure of the bones to fuse.
 

Frequently Asked Questions

How much motion in my foot will I lose after midfoot fusion?
Motion of the midfoot joints is normally somewhat limited. Loss of that motion after fusion surgery tends to be well tolerated by patients. The more mobile joints of the ankle, hindfoot and forefoot are unaffected by midfoot fusion and thus continue to provide motion to the foot.
 
Will I set off an airport metal detector after midfoot fusion?
The strength of the metal detector and the amount of metal implants used determine whether hardware from a midfoot fusion will be detected. It is uncommon for the metal implants to be detectable by airport screening methods.
 
How will I get around after surgery before I am allowed to put any weight on the foot?
A combination of devices can be used, including crutches, walkers, knee-rollers, scooters and wheelchairs. Physical therapy is also used to help assess patient needs and improve mobility and safety. Certain patients may benefit from the assistance provided by a skilled nursing facility or post-operative rehabilitation unit.
 
Will the plates and screws have to be removed after midfoot fusion?
Metal implants used for midfoot fusion are not routinely removed. Hardware may need to be removed if there is a failure of the fusion or if infection develops. Painful hardware can be removed once the fusion is healed.
 
The American Orthopaedic Foot & Ankle Society (AOFAS) offers information on this site as an educational service. The content of FootCareMD, including text, images and graphics, is for informational purposes only. The content is not intended to substitute for professional medical advice, diagnoses or treatments. If you need medical advice, use the "Find an Orthopaedic Foot & Ankle Surgeon" tool at the top of this page or contact your primary doctor.