If at first an injured ankle does not heal, a U.S. surgeon says there are some new techniques that may help.

Dr. Matthew Mitchell, an orthopedic surgeon in Casper, Wyo., says most ankle injuries are successfully treated with traditional "first-line" therapies, but about one-fifth to one-quarter of people with ankle injuries may need additional "second-line" restorative treatment to heal successfully.

Mitchell is lead author of an article published in the Journal of the American Academy of Orthopaedic Surgeons on several emerging techniques.

He suggests one of these -- a graft technique called matrix-induced autologous chondrocyte implantation, in which cartilage cells taken from the patient are used as seeds to grow more tissue in the lab on a special backing material or "matrix" -- benefits the patient because it is a second-line repair that may not always require an osteotomy or cutting of the tibia, the lower leg bone.

"You only need to make an incision to place the graft, which decreases the morbidity of the procedure quite a bit," Mitchell says in a statement.