On Aug. 3, 2015, plaintiff Angelica Hermosillo, 19, a medical assistant, was a passenger in a vehicle operated by her sister. As they were traveling in Bakersfield, their vehicle was struck in the rear by a trailing vehicle operated by Brent Robinson. Hermosillo claimed a back injury. Hermosillo sued Robinson and Robinson’s employer, Kevin Wood. Hermosillo alleged that Robinson was negligent in the operation of his vehicle and that Wood was vicariously liable for Robinson’s actions while in the course and scope of his employment. Robinson initially claimed that Hermosillo’s sister cut off his vehicle prior to the collision, but the defendants ultimately admitted liability for the accident on the eve of trial., Hermosillo developed lower back and leg pain, and sought treatment at an emergency department 17 days after the accident. She was ultimately diagnosed with a 10 millimeter lumbar disc bulge at the L5-S1 level. She claimed the bulge caused radicular pain into her leg. Eight months after the collision, Hermosillo underwent surgery at L5-S1 level. She then did not receive any medical care for the four years after the surgery. However, the plaintiff’s expert neurosurgeon opined that Hermosillo would eventually need surgery at the adjacent level. Hermosillo’s counsel noted that the defense’s expert neurosurgeon admitted on the stand that Hermosillo required the L5-S1 surgery after the collision and deferred to Hermosillo’s expert neurosurgeon on future care recommendations. Hermosillo sought recovery of past and future medical costs, and damages for her past and future pain and suffering. Defense counsel disputed causation, and the nature and extent of Hermosillo’s . The defense’s biomechanical expert was expected to testify that the collision could not have caused Hermosillo’s alleged spinal . However, based on plaintiff’s counsel’s motion, the court excluded the expert from testifying at all.