Pig Ligs


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Your body probably doesn’t have any pig parts-unless you ate bacon for breakfast. But at least five skiers at Aspen Valley Hospital have been implanted with swine intestines to repair torn knee ligaments.

Studied by biomedical engineers at Purdue University over the past decade, the pig intestine (called SIS for small-intestine submucosa) acts as a “scaffold” for new ligaments. As new tissue grows around the SIS, it is gradually absorbed into the body until nothing but healthy ligaments remain.

Traditional knee surgery involves removing tendons from around the knee to replace a torn ligament. “That way, we’re robbing Peter to pay Paul,” says Dr. Rob Hunter, the orthopedic surgeon pioneering the technique. “With SIS grafts we’re not taking anything from the body.” The operation takes about an hour. Full recovery (about six months) and price are comparable to standard ACL surgery. But since SIS grafting is experimental, most insurance companies won’t pay for it.