On April 6, 2010, plaintiff Victor Marquez, 50, a truck driver, was operating a big rig truck, a 2010 Freightliner, on the eastbound State Route 60 in the city of Industry when he slowed to stop with the rest of traffic. Subsequently, his truck was rear-ended by another big rig truck, a 2009 Kenworth, which was being operated by Conrad Rios, and Rios’ big rig was rear-ended by a third big rig truck, which was operated by Marco Silva. Upon impact, Marquez was forcefully jolted forward and backward inside his truck while seat belted. Paramedics then arrived on the scene and examined Marquez, whom complained of back and ankle pain, and was transported to St. Jude Medical Center. Marquez sued Rios; the owner of Rios’ truck, BP Products North America Inc.; Silva; and the owner of Silva’s truck, Americus Logistics. Marquez alleged that Rios and Silva were negligent in the operation of their respective big rig trucks. He also alleged that BP Products was vicariously liable for Rios’ actions and that Americus Logistics was vicariously liable for Silva’s actions. Plaintiff’s counsel contended that Rios failed to timely stop his truck and avoid rear-ending Marquez’s truck. Counsel also contended that Silva failed to stop as the traffic in front of him came to a stop, causing a chain-reaction rear-ender accident. Rios’ counsel contended that the brakes on Marquez’s trailer were not functioning properly, as seen in Rios’ BP truck drive-cam. Thus, Rios claimed that he could not see Marquez’s vehicle slowing down. Silva contended that he was travelling behind Rios and was unable to stop his vehicle in time., Marquez sustained a fibular fracture of the ankle and a 5-millimeter lumbar disc bulge at the L5-S1 level. He subsequently underwent ankle surgery 18 months post-incident, and a lumbar discectomy and fusion two years after the accident. Thus, Marquez claimed approximately $280,000 in medical expenses, as well as sought recovery for unspecified damages for his pain and suffering. Defense counsel contended that Marquez sustained an ankle injury because the driver’s seat was defective and dislodged during impact, causing it to slide forward and strike Marquez’s ankle. Counsel further contended that Marquez did not sustain a lumbar injury in the event in light of the fact that he did not treat for any lumbar pain for several months after the accident.