On Jan. 26, 2009, plaintiff Hyun Jae Kim, 40, a truck driver, was driving his tractor-trailer in the course and scope of his employment for Swift Transportation on westbound Interstate 44 in an unincorporated area of Jasper County, Mo. As Kim was proceeding downhill on an icy road at less than 20 mph, he was rear-ended by another tractor-trailer and pushed into a sport utility vehicle. Kim’s trailer jackknifed and came to rest in the center median. He claimed to his neck, lower back, and both shoulders. Kim filed a claim against Gainey Transportation Services Inc., the owner of the tractor-trailer that rear-ended his truck. Kim alleged Gainey Transportation was vicariously liable for its employee’s actions. Gainey Transportation admitted liability for the accident., Following the accident, Kim complained of neck, lower back, and shoulder pain. He was subsequently taken from the scene of the accident by ambulance and brought to an emergency room, where he was diagnosed with a disc herniation at L5-S1 with impingement. He later underwent a laminectomy on July 2, 2009. Kim claimed the accident also exacerbated prior cervical complaints dating back to a motor vehicle accident on Dec. 18, 1994, in which he sustained multiple and required a C12 fusion and other treatment. Kim claimed he tried to return to work after the subject accident, but had to quit his job since he was unable to continue his duties as a truck driver due to continuing lower back pain and bilateral lower extremity pain. Thus, he claimed $170,377.55 in past medical costs (worker’s compensation lien), and sought recovery of damages for his future medical costs, lost earnings, and pain and suffering. The insurance carrier for Gainey Transportation claimed that Kim’s cervical complaints were all due to his pre-existing neck condition and treatment, and was not caused or exacerbated by the January 2009 accident.