Whenever I see a new search engine recommended, I usually plug "fibular hemimelia" into its search box for my trial run. The condition basically boils down to being born missing a fibula--and often (though not in my case) some toes. Other leg issues, like a shortened femur, missing ligaments, etc., may also be present (as in my case).
"fibular hemimelia" in Wheeless' Textbook of Orthopaedics
When I was born (1974), amputation was by far the most common treatment. The alternative: a lengthy series of surgeries, many experimental, designed to promote tibia growth and counter a leg length discrepancy. My right leg's growth was "stimulated" in a variety of ways including a fasciectomy; my left leg's growth was stunted, and I'm now at a difference of about 3 inches, for which I wear a lift (I may eventually undergo leg lengthening surgery to even 'em out, but I'd need a couple other surgeries first to make my leg strong enough to withstand the lengthening--and as an adult working a 40-hour job, that kind of free time/leave isn't anywhere near as available to me as it was when I was a student or working part-time). I remember feeling very lucky to have been born in a time when (and metro area where) alternatives to amputation were possible, if rare.
Interestingly, what I've found searching "fibular hemimelia" in the last year or so is that amputation is once again the most common (even most desirable) treatment--and that apparently "children who undergo early amputation are more active, have less pain, are more satisfied, have fewer complications, undergo fewer procedures, and incur less cost than those who undergo lengthening." ("Fibular Hemimelia: Comparison of Outcome Measurements After Amputation and Lengthening" in The Journal of Bone and Joint Surgery 82:1732 )
I've grown up thinking of amputation--in regards to fibular hemimelia--as a primitive solution that modern medicine made it possible for me to avoid. The surprise? All the below folks were born with fibular hemimelia, are significantly younger than I am, and opted for amputation. You may have heard of the first one or two.
"Amputee Ineligible for Olympic Events" from the New York Times
"Pistorius, 21, was born without fibulas and had both legs amputated below the knee when he was 11 months old. But in the four years since he started competing, he has set Paralympic world records in the 100, 200 and 400 meters and it was his dream to compete in the Olympic Games."
UPDATE: This was just overruled--Pistorius might compete.
Wikipedia article on Aimee Mullins, model/actress/athlete born in 1976 with fibular hemimelia in both legs, both of which were amputated. "She has been named one of the fifty most beautiful people in the world by People." Mullins at MyHero: "Without her legs, she could still learn to walk with artificial ones. With her legs, she would have been confined to a wheelchair for the rest of her life."
Team Ossur Member Jeff Skiba--The First Amputee in History to Clear Seven Feet in the Men's High Jump
"Born without a fibula in his left leg due to a congenital defect known as fibular hemimelia, doctors amputated [the 24-yr-old's] leg below the knee when he was less than a year old."
Oak Park Hockey Player Isn't Held Back by his Prosthetic Leg
"Now a junior at Oak Park, Brown scored seven goals in 19 games this season. That's no small accomplishment for any player, particularly Brown, who was born in 1990 with fibular hemimelia in his right leg...Tonya Brown, Jake's mother, says the family consulted with doctors all over Kansas City, but few had even heard of fibular hemimelia. The early prognosis was that Jake would never walk...The Browns finally found comfort at Shriners Hospital in St. Louis when they met a family from Indiana with a daughter Jake's age who also had the condition. Additionally, the Shriners doctors were familiar with the condition...Unfortunately, the best course of action was amputation."
Racing to the Paralympic Games
"Tyler Carter of Topton is a typical 14-year-old...And oh, by the way, Tyler has only one foot. Tyler was born with fibular hemimelia, a congenital condition that left him without a fibula bone in his right leg. As a result, the leg was amputated below the knee when he was 1, leaving him with what he jokingly refers to as 'my stump.' Despite his disability, Tyler is a competitive skier who often beats able-bodied competitors in races held throughout the Poconos..."