Juvenile allograft transplantation, sometimes known as the DeNovo natural tissue graft implantation, is a fairly new surgical technique, performed to replace damaged cartilage in the ankle with cartilage from a donor. Cartilage is the smooth coating on the end of the bones that provides cushioning and support for comfortable and fluid movement of the joints. Cartilage damage may occur as a result of injury or degeneration and can lead to severe pain and arthritis. Eventually, the damaged cartilage can wear away and leave the bone unprotected.
Juvenile allograft transplantation received its name because the healthy cartilage tissue used for the procedure is harvested from donors under the age of 13. Juvenile tissue contains a greater quantity of chondrocytes, or healthy cartilage cells, than adult tissue, giving the patient a better chance of the joint healing. While most cartilage used in juvenile allograft transplantations come from a cadaver donor, the cartilage may also be taken from a living patient. In some cases, juvenile bovine cartilage material may be used instead.
Juvenile allograft transplantation is considered a minimally invasive alternative to more intrusive cartilage treatments since it eliminates the need to harvest tissue from areas of undamaged cartilage. The main goal of this procedure is to relieve pain and restore movement and function to the ankle.
Candidates for Juvenile Allograft Transplantation
Ideal candidates for juvenile allograft transplantation are patients who have an osteochondral lesion of the talus . These patients often experience pain and swelling weeks or months after the initial trauma or injury, and the pain has become progressively worse with time. When conservative treatment measures fail, surgical intervention may be necessary to alleviate the discomfort. Juvenile allograft transplantation is especially beneficial for patients with large or refractory cartilage lesions.
The Juvenile Allograft Transplantation Procedure
Prior to surgery, MRI or CT scans will be performed to determine the location and size of the cartilage lesions. A diagnostic arthroscopy may also be performed to thoroughly visualize the ankle lesion. Small portions of cartilage are harvested from the donor in preparation for the procedure, and these are formed into grafts. Next, the donor tissue is examined, sterilized, prepared and tested to ensure it is all healthy and that there will be no disease transmission prior to the transplantation.
Juvenile allograft transplantation is performed under general anesthesia through an arthroscopic technique. After an incision is created, the affected ankle cartilage lesion will be removed and a viable space for the healthy donor cartilage is created. Fibrin glue is applied to the lesion base, and the healthy cartilage pieces are inserted into the space through a cannula. An additional layer of fibrin glue is then used to fully embed the cartilage tissue. Once the graft is securely placed, the incisions can be sutured closed. The healthy cartilage cells from the transplanted cartilage will begin to integrate with surrounding tissues, multiply and produce new cartilage tissue.
Recovery from Juvenile Allograft Transplantation
Following juvenile allograft transplantation, patients will usually be advised to avoid putting pressure on the ankle joint for at least 6 weeks. The patient will wear a splint to maintain a normal position for the joint until the sutures are removed. Two weeks after surgery, the patient may be switched out of the splint and into a removable boot brace instead. At this time, strengthening exercises are typically started to help restore complete function to the ankle.
The length of time for a complete recovery following juvenile allograft transplantation varies by the individual patient, but frequently takes up to 6-12 months.