 Consumer Business News, Erin Reyal, NBC Newsradio. 2.54 now on WDEL, and with Healthwatch this afternoon, here's Elizabeth Tracy. Tendons connect muscles to bones. When an injury to the Achilles tendon in the lower leg occurs, it's most often a tear between muscle and tendon. But in the shoulder, it's a separation between tendon and bone. That's according to shoulder expert Edward McFarlane at Johns Hopkins.