Costello CA, Liu M, Furey A, et al. - This study was attempted to evaluate the relationship between epidemiological factors and nonresponders to total joint replacement surgery in primary osteoarthritis patients. Researchers ascertained the nonresponders (pain nonresponders, function nonresponders, pain and function nonresponders) applying the WOMAC change score from baseline to follow-up under two previously reported criteria. They examined 88 self-reported factors collected by a general health questionnaire for associations with nonresponders. The study included a total of 601 patients (30.8% hip and 69.2% knee replacement); 18% of them were found to be either pain or function nonresponders. The outcomes implied potential roles of pain perception, widespread pain sensitization, patient expectations, and early menopause in females in total joint replacement outcomes, warranting future study.