Therapy dogs are making a big impact in healthcare and have become more of the norm than the exception any more. Their work ranges from helping kids with autism to comforting those dealing with chronic pain. Animal Assisted Therapy (A-A-T) uses trained animals to enhance a person's physical and emotional well-being and experts say these dogs help facilitate the healing process.

Dr. Elizabeth Johnson, who is the Medical Director of the Polytrauma Rehabilitation Center, in San Antonio, Texas, believes that therapy dogs are the most holistic approach to treatment. A study found therapy dog visits to chronic pain patients led to significant reduction in pain and emotional distress. Research also shows therapy dogs lowered autistic children's stress hormones or cortisol levels by 48 percent, which points to potential behavioral benefits.

For example, Sergeant Matthew Krumweide lost both legs and severely injured his arm while serving in Afghanistan. Sgt. Krumweide talks about the impact of his therapy dog, Kelsie, "I stepped on an IED. Rehab's been hard, but Kelsie makes it easier."

His case in point is one day when during physical therapy, he was struggling while working on his arm's range of motion. He said that when Kelsie came in, the pain just went away. "I was able to get there, get to 90 degrees," Sgt. Krumweide said. Meanwhile, he is improving day by day. He's working on walking and eventually wants to snow ski. He knows that its going to be hard work but trust that he can do it with Kelsie close by to help him through it all.

Pet therapy is crucial because it can help lower anxiety, decrease blood pressure, shorten hospital stays, and improve patient outcomes. Just a dog's presence can also have an interesting effect on the rest of us. A Japanese study found just by looking at their dog, an owner's oxytocin levels increased. Oxytocin is a chemical produced by the pituitary gland that's associated with human bonding. It is an amazing relationship that we have with our canine best friends.