On Aug. 11, 2014, plaintiff Kenneth Parsons, 60, an ambulance mechanic, was in his vehicle on Lakeville Highway, in Petaluma, when his vehicle was rear-ended by a vehicle operated by Robert Martinelli. Parsons claimed to his left shoulder. Parsons sued Martinelli, alleging that Martinelli was negligent in the operation of his vehicle. Martinelli claimed that he could not avoid the collision because Parsons made a sudden stop at a traffic signal, which contributed to the accident., Two days after the subject accident, Parsons sought medical care and was diagnosed with severe osteoarthritis in his left, non-dominant shoulder. He subsequently underwent over 18 months of conservative treatment, which included injections and physical therapy. He then saw an orthopedic surgeon, who recommended shoulder replacement surgery. In February 2016, Parsons underwent a reverse shoulder arthroplasty. At trial, Parsons contended that his left shoulder osteoarthritis was asymptomatic prior to the collision, but that the subject crash made it symptomatic. He also alleged that he could no longer work on classic cars like he did in the past or play with his grandchild. Two of the plaintiff’s treating physicians testified that the accident was a substantial factor in causing the need for the shoulder replacement surgery. Parsons’ orthopedic surgery expert also opined that the shoulder replacement surgery was related to the accident. Parsons contended that he could potentially need a second surgery to his left shoulder in the future. Thus, plaintiff’s counsel asked the jury to award Parsons $1.6 million in total damages. The defense’s orthopedic surgery expert opined that the shoulder replacement surgery was the result of Parsons’ pre-existing, degenerative osteoarthritis and was not related to, or caused by, the subject accident. Thus, defense counsel asked the jury to only award damages in the area of $50,000.