Airman 1st Class Spencer Stone didn't think twice before he and his friends stepped in to thwart a terrorist attack on a Paris train, and his selflessness resulted in a potentially disabling cut to his hand.

However, thanks to the skillful work of surgeons in Paris and the expert therapy he's receiving from Army medical professionals at Landstuhl Regional Medical Center, he is expected to regain full use of his hand.

Stone received a deep laceration at the base of his thumb that severed the tendon and nerves that run along the inside of the thumb, according to Lt. Col. Arthur Yeager, LRMC's Chief of Occupational Therapy.

According to Yeager, the cut appears to be a defensive wound from when the would-be attacker sliced at him with a knife, while Stone and the other heroes on the train attempted to subdue him.

"Stone said everything happened so quickly he doesn't recall exactly how he was cut," Yeager said. "The tendon that was severed allows you to flex the thumb and use it to grasp things, and without it, you can't really use your thumb."

Yeager says the excellent care Stone received at a French hospital has set him on a path to a complete recovery.

"Thanks to our counterparts in France, he underwent surgery that same day, which is critical," Yeager said. "What tends to happen is that the longer you wait to repair the cut, the harder it is to get more range of motion and the harder the rehab will be."

The nerve that provides sensation to the thumb was also severed, but the French surgeon was able to repair the nerve and sensation is already returning to his thumb.

"Normally, when a nerve is severed and then repaired, it could take up to a year before full sensation returns," Yeager said. "He already has some sensation in his thumb just days after the surgery, and that's a testament to the skill of the surgeon. Fortunately for him it was also a clean cut, so that also made the repair easier."

Yeager believes that it will take anywhere from three to four months for Stone to regain full use of his thumb.

"He is receiving therapy daily, we are changing his bandages, assessing the condition of the wound, and doing range of motion exercises with the thumb to ensure it doesn't stiffen up or become re-injured," Yeager said.

Occupational therapy helps people of all ages with temporary or permanent impairments to return to optimal performance through the use of everyday activities.

"It's more about function than just body parts, so our focus is on returning people back to the things they do every day," Yeager said.

According to Yeager, it takes six weeks for a repaired tendon to be able to sustain a load, so it's crucial that he doesn't use it during that time.

"Our occupational therapy team designed a custom-made splint for his hand that will prevent him from moving the thumb, so that he can't damage the repair to his hand," Yeager said. In the meantime, we will continue to do therapy to keep his thumb mobile and prevent it from becoming stiff from lack of movement."

So far, his OT care team, consisting of Capt. Ashley Welsh, Staff Sgt. Tischa Hall, Sgt. Aaron Keller and Kirby Kirkland, believes that his prognosis is excellent.

"He looks great for how recently he had surgery," Yeager said. "He has very little swelling, the wound looks excellent and there's no sign of infection, and he has really good range of motion. Everything looks great, so far. Within three months he will be working on strengthening the hand and he should be able to resume all the activities he was doing before."

It hasn't been determined how long Stone will receive care at Landstuhl, but Yeager says he is receiving the best care possible, and the same level of care will continue wherever he goes next for treatment.

"Over the last 14 years more than 90,000 Wounded Warriors have been treated here at Landstuhl; many with much more severe injuries, so it's refreshing to have a patient with such a positive outcome. Unfortunately, not all of our heroes leave here whole."

Yeager says that Stone, an Ambulance Services Technician stationed at Lajes Field in the Azores, has been a great patient and that they've enjoyed seeing him and hearing about how his life has changed as a result of his experience.

"We are very proud to be able to help Airman Stone on his road to recovery," Yeager said. ""He is a true testament to the caliber of the men and women in our military today."