PATRICK ROY'S career wins record is about to be erased, but his lasting legacy, the widespread use of butterfly goaltending, remains strong. Nearly all goalies use the limb-splaying style at least on occasion, and the result has been both a steep drop in goals against and a rash of hip injuries. In the estimation of Marc Philippon, an orthopedic surgeon who has operated on dozens of athletes—and who did the arthroscopic procedure on Alex Rodriguez's torn labrum on Monday—10% to 20% of adults have a structural problem with their femurs, the bones that run from knee to hip. If the femur head, which fits into the cup on the side of the pelvis to make the hip joint, is not cue-ball round, then repetitive motion that jams the misshapen ball into the socket can scrape away the natural padding and tear the labrum, a band of cartilage that rings the hip joint and secures the head of the femur.
Dropping into the butterfly is just such a motion. An NHL goalie who drives down for a save can slam the head of his femur into the socket with the same force that an Olympic weightlifter does when performing a clean and jerk, according to research by McGill University and hockey equipment maker Nike Bauer. Multiply that by 500 repetitions a day and you start to pity the cartilage.
Roy himself had hip troubles late in his career with Colorado, and, says former Avalanche trainer Pat Karns, "we had to work on Patrick daily [to keep his hips healthy]." Roy avoided surgery for the condition, but some A-listers from the generation that grew up idolizing, and imitating, St. Patrick have not been so lucky: the Ducks' Jean-Sébastien Giguère, the Islanders' Rick DiPietro, the Flyers' Antero Niittymaki, the Maple Leafs' Vesa Toskala and the Sabres' Patrick Lalime are just some of the active goalies who needed surgery to shave the heads of their femurs into perfect spheres. "My hips were always sore [before surgery]," says Giguère. "I was fighting against them every time on the ice."
The hip condition, femoroacetabular impingement, also tends to manifest itself as back pain or groin pulls. If the condition goes unrecognized (an MRI after a dye injection into the joint is the best way to spot a torn labrum), a goalie could be at risk for early arthritis. Some precaution—avoiding deep squats with heavy weights, for example—can minimize the stress on the joint but won't necessarily prevent injury, says Philippon. The butterfly is so effective in closing off the lower portion of the net that goalies will use it regardless of the risk. Six years after Roy's retirement his influence is still felt, often painfully.