The final equation: reinforce that joint with a few good exercises

Sean McEnroe, a veteran physical therapist who works with celebrity athletes from Vail's Steadman Hawkins Clinic, recommends the following short-term goals for post-ACL surgery patients (below). He's also provided a regimen of eight ski-specific exercises to get you back on the slopes (right). Though designed for skiers, this workout will strengthen the muscles that protect your knees no matter which sport you're getting back into—and they're ideal for preventing knee trauma if you've never been injured. McEnroe suggests doing this program three days a week, but stresses that it's critical to obtain clearance from your physical therapist before attempting any of these exercises.

Weeks 1–2: Decrease swelling with ice; increase range of motion with simple stretching exercises.
Weeks 2–6: Begin nonimpact cardiovascular exercises such as spinning on a bike with no resistance; look to get clearance to ditch the crutches.
Weeks 6–12: Work on endurance strength (high repetition, light resistance) by riding a stationary bike, running in a pool, or walking on a treadmill.
Weeks 12–16: Begin agility drills like balance squats to rebuild proprioceptor nerve endings, which help control balance and are severed during surgery. Also work on exercises that mimic sports (e.g. side-to-sides).
Week 16: Begin workouts on grass and routines using free weights and on exercise machines.
Week 20: Develop explosive muscles using miniplyometrics, i.e. drills incorporating small jumps like the skier's hop.
Week 24: Begin full-on participation in your sport.

BALANCE SQUATS
With one foot back and resting on a chair and the opposite foot forward, lower your torso straight down toward the floor and then rise up—your knee should never be ahead of your front foot. Do continuous, slow repetitions for 30 seconds and build to three minutes. Advanced: Add a miniplyometric by bursting on the way up, clearing three to six inches off the ground, and then landing softly. Goal: One three-minute set.

BALANCE STRETCH
Hold your right ankle behind you with your right hand, as if stretching the quad muscle. Slowly lean forward with your arm outstretched, hold the position for ten seconds, and then return to the start and switch legs. Goal: Ten stretches with each leg.

SKIER'S HOP
Start with your left leg on the ground and your right leg planted on an 8- to 12-inch-high platform. In one motion, use your right leg to leap laterally over the platform and land in the opposite of the starting position. Repeat, leaping from side to side in a quick, controlled motion. Goal: Three three-minute sets.

SIDE-TO-SIDE
Anchor a sport cord—rubber tubing with handles (find one at a stationary object. Don a waist belt, attach it to the sport cord, and lean far enough away to put tension on the cord. Hop on one foot laterally away from the anchor point, hold for two seconds, and then hop back to the starting position. Keep your legs slightly bent throughout. Goal: Two sets, 40-50 reps each.

ONE-LEG DIP
Like balance squats, but accentuates the quads more than the hips. Stand on your injured leg with the other leg balanced in the air behind you. Place one hand on a wall or chair for added stability. Slowly lower yourself until your thigh is 70 degrees to the ground and then stand back up. Add a sport cord for resistance. Goal: One three-minute set.

Also do: hamstring curls, leg presses, and calf raises. Three sets, 20 to 30 reps each, three times a week.—C.K.

ACL Surgery Demystified

Mark Schroeder

Biking, skiing, snowboarding, and trail running can all end disastrously with a hyperextended or twisted knee. Stretch your delicate anterior cruciate ligament beyond its tensile strength and a distinct champagne-bottle pop will likely follow. Not good; it's the auditory calling card of a torn ACL. "With a small tear, if there is no looseness in the joint, you could just do rehabilitation," says Richard Steadman, Picabo Street's orthopedic surgeon, who may have just saved you $20,000 in surgical costs. "But a full tear that weakens the joint will require a full reconstruction."

If you're in for the latter, there are two ways to go. World-class athletes almost universally prefer Steadman's method of using strands from the patellar tendon (see knee diagram, above), rather than the more common approach of grafting the hamstring tendons, to build a new ACL. "We did a study that found the [hamstring] is used throughout the ski turn," Steadman says. "You may lose something at the highest competitive level if you use that tendon."

The downside is that rehabilitation for a patellar graft can keep you off your feet longer and in a lot more pain than a hamstring graft, and it has the potential to cause tendinitis down the road. For the recreational athlete, stealing from your hamstring is the ticket, according to John Garrett, former chief resident of orthopedics at Harvard and founder of Atlanta-based Resurgens, which treats NFL players. "If you're aggressive, you can be off crutches in four to five days, on a bicycle by the end of a week, and back in your office," he says. "A patellar graft can keep you on crutches for up to six weeks." The success rates for both procedures hover in the 90-percent range. Either way, pick an orthopedic surgeon who subspecializes in knee operations and has a high-volume practice. And keep in mind that surgery is just the first step to becoming the badass you once were. "You have to go into it with the idea that more than half the job is yours," says Steadman. "The surgery is two hours, but the recovery is six months."—C.K.

The following Web sites can help you evaluate surgeons who specialize in knee surgery:
American Orthopaedic Society:
Steadman Hawkins Clinic:
American Academy of Orthopaedic Surgeons: