Abstract: On February 1, 2011, Employee #1, a 45-year-old tree worker with Ronald D Little dba AAA Tree Service, was part of a crew trimming and topping trees at a residential house. Employee #1 an experienced tree climber, positioned himself in a tree and had his flip line around the trunk of the tree but was not secured via a safety line. Upon cutting a large top section of trunk that had been attached to a rope, the crew below pulled the cut section to allow it to fall to the ground. As the section of trunk was pulled off the tree, it created a vibrating action. According to Employee #1 this caused his flip line to pop off the remaining tree trunk, which in turn, caused him to fall to the ground below. Emergency Medical Services responded, and Employee #1 was transported to UC Davis Medical Center in critical condition. Employee #1 sustained a broken back/spine, fractured ribs, fractured sternum, punctured lung, torn aorta, and other internal injuries as well as being permanently paralyzed from the navel down. The employee was scheduled to be discharged from the hospital at the end of March.