Emerging Advances In Ankle Cartilage Repair
With this technique, the surgeon would graft an osteochondral plug from a non-weightbearing surface, usually from the knee, and transplant it into the damaged area of the talus. Alternatively, one can take the graft as multiple plugs, creating the mosaicplasty effect. Depending on the location of the lesion, a malleolar osteotomy may or may not be required.
In their retrospective study, Scranton and colleagues had good to excellent results of 90 percent at a mean follow-up of 36 months with the OATS procedure.5 It is important to note that 26 out of 50 patients required a malleolar osteotomy for adequate exposure.
The one major advantage of this procedure over autologous cartilage implantation is that the OATS procedure only requires one surgery to complete. Additionally, the surgeon is better able to restore the contour of the defective talus using the OATS procedure.
Sharpe and coworkers describe a hybrid technique in which they combined autologous cartilage implantation with OATS.6 The procedure entailed injecting autologous cultured chondrocytes under the periosteal patch of the previously inserted osteochondral cores. At the three-year follow-up, 10 of the 13 patients continued to relate favorable improvement in their symptoms. It is interesting to note that at a one-year arthroscopic evaluation, the osteochondral grafts were well integrated with the adjacent cartilage.
How An Innovative Natural Tissue Graft Can Help Reproduce Hyaline Cartilage
The development of methods to reproduce hyaline cartilage following cartilage damage has recently picked up momentum. The use of the aforementioned DeNovo NT Natural Tissue Graft has become a popular technique of doing this. This graft is made up of human juvenile hyaline cartilage. Research has shown these immature juvenile chondrocytes have a much larger capacity for self-repair in comparison to that of adult cartilage.7
There are a few other major advantages of this modality in contrast to either the OATS or autologous cartilage implantation. First, the DeNovo graft requires only one surgery, which surgeons can perform arthroscopically. In addition, no periosteal flap is required to secure the graft as surgeons can apply a fibrin adhesive instead.Lastly, no donor site morbidity is associated with the procedure since the surgery uses an allograft instead of an autograft. Although one can use the DeNovo graft for lesions greater than 0.5 cm, use caution with deeper lesions that have greater osseous involvement.
Coetzee and colleagues used the DeNovo graft to treat symptomatic osteochondral lesions on 24 ankles.8 They also note that 14 of the 24 ankles previously failed marrow stimulating surgeries.
The average lesion size was 125 ± 75 mm² and 7 ± 5 mm in depth. The average follow-up was 16.2 months. Seventy-eight percent of patients had good to excellent scores using the American Orthopedic Foot and Ankle Society Ankle-Hindfoot Scale. More specifically, 92 percent of patients with lesions that were 10 mm or larger and patients with lesions smaller than 15 mm demonstrated good to excellent results.
Exploring The Potential Of Orthobiologic Stem Cell Therapy
Without a doubt, the most exciting and promising innovation in tissue repair over the past few years has been stem cell therapy. Due to their pluripotent capabilities, mesenchymal stem cells are able to differentiate into multiple tissue types. For podiatric purposes, bone marrow aspirate typically originates at either the calcaneus or the tibia, where bone marrow is abundant. The goal with injection of this aspirate is to get as close to hyaline-like cartilage as possible.