Darek Fidyka may appreciate his nose more than many other people. Not because of how it makes him look, or how it allows him to smell the fragrance of flowers, but because it’s letting him walk again.

Fidkya, was stabbed during a knife attack in his native Bulgaria when he was just 36. One of the stab wounds essentially severed his spinal cord. It left him paralyzed and unable of feel sensation from his chest down. The severed nerve cells couldn’t transmit signals to and from his brain.

When the spinal cord is severed, scar tissue begins to form, and it successfully blocks any ability of the cut nerve cells to regenerate and rejoin. Most often, conditions like this are permanent injuries. He could have expected to spend the rest of his life in that state, unable to walk, unable to feel sensations from the lower part of his body.

About 40 years before the attack on Darek, Dr. Geoffrey Rasiman, from the United Kingdom, was working on experiments using nerve cells. He showed that damaged nerve cells can form new connections. As his work progressed over decades, he also found that a specific type of cell in the brain, called olfactory ensheathing cells (OECs), can allow nerve cells to regrow.

Studies in rats showed that their OECs, when transplanted to their spinal cords, could cause previously damaged cells nerve cells to repair themselves. As that happened, the animals regained some use of previously paralyzed limbs.

A neurosurgeon from Poland, Dr. Pawel Tabakow, was interested in working on patients who had spinal cord damage. Though the severed cord couldn’t be repaired and the nerves made to function again, he was using techniques to try to minimize the scarring and other neurological damage that could occur. He was using neuroprotective techniques, and having patients undergo intense neurorehabilitation with physical therapy, electrostimulation and other techniques. Tabakow became aware of Raisman’s work. They began to correspond, and Tabakow invited Rasiman to Poland to collaborate.

They worked out a technique to attempt to treat human victims of spinal cord transsection. They would take some of the patient’s brain tissue containing OECs, and get the OECs to multiply in tissue culture. Then they’d take strips of nerve from the patient’s leg to serve as a physical bridge between the two severed sections of his spinal cord. Next they’d inject the cord in the area of the cut hundreds of times with small volumes of solution containing OECs. Theoretically, the OECs would stimulate the previously cut, but still living, nerve cells to regenerate and reconnect.

Fidyka was one of three patients chosen for the initial trial. He had a small amount of his brain tissue removed, grown, and injected as described. He continued with intensive neurorehabilitation for, usually, five hours per day for months. He has gradually had the return of both some motor and some sensory function in his lower body. Using a metal support frame, he can slowly walk. He ’s not graceful, and he’s very slow, but he can walk. He’s also regained some control over his bowels and bladder, and sexual function. He’s now able to live a little more independently than he was before. The rehabilitation specialists have actually started working with him to further increase his mobility by helping him learn to drive a car.

Researchers are planning to do similar operations in 10 other patients to see if they can achieve similar results in them as they did in Darek.

[Fidyka says] walking again – with the support of a frame – was “an incredible feeling”, adding: “When you can’t feel almost half your body, you are helpless, but when it starts coming back it’s like you were born again.”

Raisman said, upon seeing Fidkya walk: “[This is] more impressive than man walking on the moon.”