On Jan. 2, 2016, plaintiff Christopher Sullivan, 49, a fraud investigator for an insurance company, fell from a Tricam Commercial Type II step stool, model RM-SLA3, while in the garage of a house that he was renting. Sullivan claimed to his left shoulder as a result of falling onto his left shoulder and arm. He also fell onto his tailbone. Sullivan sued the manufacturer of the step stool, Tricam Industries Inc., and the operator of the store where he purchased the step stool, Costco Wholesale Corp. Sullivan alleged that Tricam defectively designed and manufactured the step stool and that Costco and Tricam were both negligent for selling the defective product. The negligence claim against Costco was dismissed with prejudice during trial, and the matter continued against Tricam only. In regard to the design-defect claim, Sullivan’s expert mechanical engineer opined that certain reinforcements should have been used to increase the stability and bending resistance of the rear rails, as step stools, unlike ladders, are designed for users to stand on the top cap. In regard to the manufacturing-defect claim, the expert opined that internal ribs of the step stool and the left rear rail were undersized and did not comply with design specifications, causing the rear rails to fail. The defense’s expert mechanical engineer performed various tests on an exemplar step stool, and videos of that test, along with other tests, were presented to the jury. The expert opined that the step stool complied with applicable standards, per the American National Standards Institute, and did not contain a design defect. The expert also opined that some of the measurements taken by Sullivan’s expert engineer were not accurate and that any purported variance with the design specifications at the fracture sight were due to stretching of the aluminum when Sullivan impacted the rear rails when he fell onto the step stool, as Sullivan testified that the step stool was underneath him after the fall. The defense’s expert testified that while performing various tests on an exemplar step stool, he found that even if the area of the rear rails were too thin because of an alleged manufacturing defect, the ladder could still withstand four times the load of the ANSI requirement, even if the stability of area of the fracture site was weakened by more than 50 percent by drilling holes into the rear rails. The expert further testified that based on his findings, he believed that Sullivan fell off the step stool due to his own actions and that the damage to the rear rails was caused by Sullivan falling onto it. In response, plaintiff’s counsel argued that the defense’s expert engineer changed his opinion about the dynamics of the fall at trial. The expert authored a report in April 2018 stating he believed Sullivan lost his balance, causing the step stool to tip to the left, after which Sullivan fell on top of it on his right side, causing the step stool to break. However, at trial, the expert testified that Sullivan fell on top of the step stool on his left side. During cross-examination, plaintiff’s counsel questioned the expert about the opinion change by arguing that the April 2018 opinion was not consistent with his accident-reconstruction protocol, as Sullivan had no visible to his right side, but, instead, claimed on his left side. However, defense counsel argued that their expert did not change the opinions contained in the initial report and that the expert supplemented his opinions at trial regarding Sullivan’s post-fall location on the floor of the garage after the expert read an eyewitness’ deposition taken in September 2018 and after inspecting the accident site in October 2018. Defense counsel further noted that Sullivan’s engineering expert never inspected the accident site., Sullivan presented to a Kaiser facility three days after the fall and was diagnosed with an impingement of the left, non-dominant shoulder and acromioclavicular osteoarthritis. He also claimed back pain and an elbow injury, but those conditions resolved shortly after the accident. Sullivan ultimately underwent an arthroscopic subacromial decompression and a Mumford procedure, also known as a distal clavicle excision, on his left shoulder on Sept. 29, 2016. Sullivan claimed that he does not have any residual problems with his left shoulder and that he does not require any future medical expenses. However, he claimed he took three weeks off from work after the surgery and that he is hesitant to engage in certain activities, like skiing, for fear of falling onto his shoulder and causing damage. Plaintiff’s counsel asked the jury to award Sullivan between $150,000 and $200,000 in total damages, including $36,372.77 for past medical expenses from Kaiser, $6,000 for past wage loss, and the rest for Sullivan’s past pain and suffering. Defense counsel stipulated that the Kaiser charges were reasonable, but disputed that they were all necessary. Counsel noted that Sullivan had undergone a prior arthroscopic procedure on his right shoulder in October 2013 due to a skiing accident. Counsel also contended that Sullivan’s primary care physician initially ordered Sullivan to undergo physical therapy for his shoulder complaints prior to undergoing surgery, but that Sullivan failed to comply. Defense counsel argued that had Sullivan undergone physical therapy to address his impingement syndrome, Sullivan could have avoided surgery. In response, the plaintiff’s treating surgeon testified that physical therapy had been ordered, but that he could not say if it would have alleviated the need for surgery. Plaintiff’s counsel also noted that defense counsel presented no medical experts on the issue.