On Sept. 6, 2010, plaintiff Mary Walker, a customer service manager, was driving her Jaguar in the high occupancy vehicle lane on the southbound San Diego Freeway, also known as Interstate 405, in Los Angeles. When she was just north of Devonshire Street, Walker applied her breaks and slowed down due to debris on the road. However, Christian Carrillo, who was traveling behind Walker in a Ford F-150, was unable to stop in time and rear-ended Walker’s car. Carrillo’s vehicle was towed from the scene of the accident, and Walker claimed neck . Walker sued Carrillo, alleging that Carrillo was negligent in the operation of the Ford F-150. Specifically, Walker claimed that Carrillo was traveling at an unsafe speed and failed to keep a proper lookout., Walker claimed that she suffered a 2-millimeter paracentral disc bulge at the C6-7 level and an aggravation of a 3.5-millimeter dorsal spondylotic ridge at the C5-6 level. She subsequently treated her cervical spondylosis with a cervical epidurography and a cervical epidural steroid injection via catheter under fluoroscopic guidance. She also treated the cervical disc bulge with bilateral, cervical facet injections under fluoroscopic guidance and a cervical epidurography. However, Walker maintained that she continued to have high levels of pain and was unresponsive to the initial treatments. Therefore, she underwent an anterior cervical discectomy, an interbody fusion with an interbody graft, plate fixation, and iliac crest bone marrow aspiration. She then followed up with six weeks of physical therapy. Walker claimed that she suffered from high levels of depression while she was in pain before the surgery. However, she claimed that the surgical procedure was successful and that after her course of physical therapy, her neck pain was reduced, and the bilateral soreness and tightness was reduced. She also claimed she regained her balance. Defense counsel asserted that Walker’s condition was caused by her pre-existing arthritis.