Benjie Wrubel, 10, has the biggest grin ever for his friend Sammie when he sees her when he arrives for pottery class at Bemis Art School.Sammie, 3 1/2, in turn, wags her tail at top speed.“She’s a really nice dog, I don’t have a dog at home and I feel connected,” Benjie says.Sammie is the unofficial greeter at the school run by the Colorado Springs Fine Arts Center.From behind the reception desk, she loves to receive pats from her many fans. Sometimes she sticks her head under the gate to get a better view of what  is going on and to accept treats. Beside friending regular summer art students such as Benjie, Sammie provides her special brand of  therapy for at- risk kids from Griffith Centers for Children and other schools.But these days the 90-pound Labrador retriever isn’t feeling so hot, and friends are trying to raise the money for a costly surgery.Sammie tore her anterior cruciate ligament on her back right knee. If not treated it will become worse.On breaks she used to play a little ball.But on a trip outside Monday, she limped badly and could only sniff the wind.Sammie is the companion of Carol Mercogliano, Bemis administrative assistant. Mercogliano has health problems of her own, and her doctor prescribed that Sammie come to work with her to help with stress. The dog has a bed under Mercogliano’s desk.The relationship started more than three years ago after her 12-year-old Newfoundland dog Buddy died. “I was devastated. A friend gave me Sammie. Her previous owner was a soldier deploying to Afghanistan.“She’s my support, my baby, ” says Mercogliano, 61. Her two children are grown.Mindy Heikkenen, a teacher assistant at Griffith Centers, calls Sammie “our therapist” because of the positive way she effects the kids. The school has art class there each Friday.One 14-year-old Griffith student , says,   “I love Sammie. I get to hug her and it makes me feel better,”Another student explains, “Sammie has a big heart even though she is hurt. It shows me I need to act that way, too.”Yet another youth notes,” I sometimes mess up and don’t trust people. Sammie makes me feel like I can trust more.”About five months ago, Sammie came up lame.Anterior cruciate ligament  injuries are common in dogs, notes Nate Miller, a veterinary surgeon at Canine Orthopedics at the Veterinarian Speciality Center of Southern Colorado. The center often does four or five such surgeries a day. (ACL injuries are technically called a cranial cruciate ligament injury. Miller notes. But  it is commonly referred to as ACL because people are more familiar with that term because its a common football or skiing injury in humans.)There are multiple surgeries which can be perfomed, with a procedure called  TPLO (Tibial Plateau Leveling Osteotomy) generally being the best option.If the surgery isn’t done, the dogs will have a persistent limp, and will be in pain when exercising. Without the repair, arthritis takes hold. It is a degenerative problem rather than traumatic, thus  a dog will sometimes get the problem on the opposite leg, too. Researchers are studying why it happens, and are looking at heredity and confirmation of the joint.Recovery takes about three months. Such surgeries can cost $3,000 or more, depending on many factors.When Tara Thomas, Bemis director of education, heard about Sammie’s plight,  she set up a fund to help pay for the surgery. To donate visit Sammie’s Facebook page:  facebook.com/SammieNeedsSurgery.(note the spelling of Sammie’s name), then, click on the Fundrazr.com link. Donors can also  contact Tara Thomas at Bemis, 477-4314.“She is just the sweetest dog,” says Thomas. “Sammie has  comforted many students, young and old, and we want to help her feel better so she can run and play ball again.”—Contact Carol McGraw: 636-0371 Twitter @mcgrawatgazette Facebook Carol McGraw