• How it works: After cleaning and smoothing the edge of the tear, surgeons pierce holes in the underlying bone. A blood clot rich in stem cells and growth factors forms in the treated area, and over time, the clot remodels into fibrocartilage, which is less supple and durable than the original, hyaline cartilage. A newer procedure called autologous matrix-induced chondrogenesis stabilizes the clot with a protective collagen membrane.
  • Who might benefit: Normal-weight people ages 15 to 50. Results are best in patients younger than 40 with healthy bone and defects smaller than 4 centimeters (about 1.5 inches) square. Microfracture can help repair cartilage in most joints, including ankles and elbows. 
  • What the experts say: “It’s not very durable after five years,” says orthopaedic surgeon Riley J. Williams III, MD, director of the Institute for Cartilage Repair at the Hospital for Special Surgery in New York. “It’s not the most effective treatment, but it’s easy to do, inexpensive and doesn’t require a lot of applied technology.”

Osteochondral Autograft or Allograft Transfer System (OATS)

The only procedure that restores true hyaline cartilage to the joint, OATS is considered a second-line treatment, but recent studies show it provides better and longer-lasting results than microfracture.

  • How it works: In an osteochondral autograft, a small plug of cartilage and bone is transplanted from a healthy area of the patient’s knee to a damaged area. (Transplanting several smaller plugs is called mosaicplasty.) For larger areas, doctors may use allografts – donated tissue from a tissue bank.
  • Who might benefit: Autografts are best for active people ages 15 to 50 with a small “pothole” in the knee, elbow, shoulder or ankle. Some people with OA or other degenerative joint disease also may benefit from allografts.
  • What the experts say: “You don’t want to create another defect  at the donor site, so this is mainly for small lesions,” says Dr. Scopp. “It’s also costly, but it’s better long-term than microfracture.”

Dr. Williams uses these transplants to ease OA pain and delay disease progression. “For people with early arthritis who aren’t ready for an artificial knee, we can do multiple large grafts. The grafts contain live cells, and over time the patient’s bone grows into and replaces the allograft bone,” he explains. Although most patients do “remarkably well,” he adds, allograft supply and a slight potential for disease transmission are concerns.