Dr. Charles Edwards, 38, is a uniquely inventive orthopedic surgeon who has added radical new techniques to skeletal reconstruction. But his business, after all, concerns more than just plastic, metal and bone. "For me," he says, "an operation is a commitment from one person to another."

In the last few months he has felt the consequences of that commitment—anguish as well as exhilaration—because of two remarkable cases involving courageous patients.

One began last July when Edwards, head of orthopedic surgery at the University of Maryland Hospital in Baltimore, operated on Mrs. Jessie Thomas, 33. A cancerous tumor was tangled around her spine, pressing on delicate nerves and blood vessels and slowly paralyzing her. In addition to removing the tumor, a 15-hour procedure in itself, Edwards also cut out six inches of her spine.

For six weeks Mrs. Thomas was immobilized while Edwards designed and had built a cylindrical brace made from an alloy of chrome, molybdenum and cobalt. It had rods on either end to fit into the spinal column. The day before he was to insert it, Edwards realized during a run-through with a cadaver that a pliers-like tool he needed for the surgery had to be modified. After staying up part of the night drilling holes in the tool to make it more maneuverable, he and a three-member surgical team implanted the cylinder, the world's first spine prosthesis. It took 16 hours. "I invoked any powers that would help me and Jessie," Edwards says. "I believed I could improve this woman's life."

Six months later Mrs. Thomas was discharged to her Baltimore home. With exterior braces, she was able to sit up. Then, on March 24, she was readmitted to University Hospital, suffering from a kidney infection unrelated to the spinal replacement. In a week the illness killed her. Dr. Edwards was stunned.

"For her to overcome such great obstacles and then die of a condition thought to be treatable was very frustrating," he understates. "In a way, the battle was won, but the war was lost." When Mrs. Thomas' husband, Ray, asked Edwards to deliver her eulogy, he canceled a long-scheduled lecture to a surgical society. "I was personally honored," he says.

Edwards majored in political science at Duke, and almost became a lawyer. But an aptitude test steered him to medicine at Maryland. He did his internship and residency at Yale-New Haven Hospital, returning to Baltimore in 1975. In 1977 he was chosen to head the shock trauma unit at the University Hospital, then its orthopedic group.

He and his wife, Gretchen, 35, have four children whom Edwards manages to spend at least one day a week with. At the hospital, in that same week, he performs three or four operations, does research, teaches and administers his 18-doctor department. He has invented a dozen reconstructive devices for bones of the arm, leg and pelvis, all of them tailor-made. "I don't invent something first," he says, "and then find a way to use it."

The publicity resulting from Mrs. Thomas' surgery brought construction worker-mechanic Gary Blackmore, 31, of El Paso, III. to Edwards in November. He also appeared in hopeless condition, with a basketball-sized tumor in his pelvic area which had blocked his normal digestive and urinary systems. One leg was paralyzed. He had not worked in six years.

In a 20-hour operation, Edwards and a team of 24 working in shifts removed the tumor, as well as nine inches of Blackmore's spine and about a quarter of his pelvis.

During the procedure his body was suspended horizontally from the ceiling so that surgeons could operate at eye level front and back. Blood was passed into his legs by tubes to maintain circulation. At one point in the operation, Edwards remembers looking through the patient's abdominal cavity and seeing the head of another surgeon through the massive hole. "It was," he says, "incredible."

Blackmore was discharged four months later and went home. Whether Edwards will later need to implant one of his metal prostheses will depend upon how well Blackmore's spine settles. He is literally three inches shorter since the operation, but his own muscles and scar tissue have formed a sling around the spine that should prevent further shrinkage. Blackmore already can lift himself to a standing position in his wheelchair; soon he'll start practicing with crutches or braces. "The prospect of walking," says a more than pleased Edwards, "is a very real possibility."