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What Is Bulk Allograft Transplantation for Osteochondral Lesions of the Talus?

Osteochondral lesions of the talus (OLTs) are ankle joint injuries involving damage to the joint surface (cartilage) and/or underlying ankle bone (talus). A normal, healthy ankle joint is made up of smooth cartilage supported by strong bone underneath. Sometimes an ankle injury leads to damaged, rough areas of cartilage and bone underneath. Foot and ankle orthopaedic specialists call this type of injury an OLT. Since the ankle joint moves while walking, the rough spots may cause pain, swelling, stiffness, and decreased motion. It is kind of like having a pothole in the joint surface.

Bulk allograft transplantation takes bone and cartilage from a human cadaver and places it into the damaged talus. This surgery is reserved for severe cases of OLT that have either failed previous surgical treatment or involve a very large part of the talus. These types of OLTs may not respond to lesser surgeries.


Treatment for OLTs depends on several factors. The size and location of an OLT is important, as are the patient’s activity level and any previous treatments. Non-surgical treatment options include medications, changes in activity, and braces or casts. Surgery may remove damaged cartilage and bone so that the underlying bone is stimulated to heal. If none of these are successful, bulk allograft transplantation is an option. 


The surgery usually is done under a general anesthetic. A nerve block may be used to help with pain after surgery. At least one incision is made, usually over the front or inside of the ankle. Commonly the tibia bone needs to be cut with a saw in order to allow access to the talus.

The OLT is then identified and removed. This is like on a golf course green where a plug is removed to make the hole. A similar plug is then taken from a cadaver talus and placed into the hole in the patient’s talus. If the tibia was cut, it is fixed with metal screws and/or a plate. The incision is closed. A splint or cast is commonly placed. The patient may go home the same day as the surgery or may stay overnight in the hospital.


Bulk allograft transplantation requires a substantial recovery period. In general, no pressure or weight is allowed on the operative side for six weeks or more. The patient typically is given a walker or crutches. A kneeling walker/scooter also may be an option. A transition is then made to partial weightbearing in a cast or boot. Daily activities are allowed between three to four months with complete recovery taking up to a year or more. 

Risks and Complications

All surgeries come with possible complications, including the risks associated with anesthesia, infection, damage to nerves and blood vessels, and bleeding or blood clots.

Specific risks of this procedure include nonunion (incomplete healing of the bones) of the graft and/or the site of the bone cuts (in the ankle), pain around the surgical site or hardware, and advancement of arthritic changes in the ankle joint. The graft may fail and collapse even several years after surgery.


What is the outcome for most people?
Most patients have less pain and are able to do more activities after bulk allograft transplantation. These improvements have been shown to last several years and may last many more.

What happens if this surgery does not work?
Patients still may experience pain with activities after this procedure. If medications, bracing and activity modifications fail to improve symptoms, revision surgery may be considered. Ankle fusion and possibly ankle replacement may be treatment options.

Can my body reject the bone graft?
Rejection of the allograft is an unusual occurrence. An allograft may fail to heal and/or break but this does not seem to be from the body rejecting the graft itself. 

Is there a risk of getting HIV or other diseases from a bone graft?
It is estimated that the risk of HIV transmission from allograft transplantation is less than one in a million. There is a risk of transmitting other viruses such as hepatitis, but the risk is one in several hundred thousand.


Original article by Jaymes Granata, MD
Last reviewed by David Porter, MD, 2018

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