Comparison of Pain and Functional State and Quality of Life of Total Knee Replacement Patient

Knee osteoarthritis is a disease that causes pain, functional limitation and disability and its incidence rate is gradually rising with an increase in the elderly population (Felson & Anderson, 1987; McKay, Prapavessis & Doherty, 2012). A total knee replacement is an effective surgical intervention for the patients with knee osteoarthritis by reducing pain in the knee joints and enhancing the quality of life and joint functions for a smoother gait. A study of the cohort of patients with total knee replacement showed a significant increase in the Short Form-36 Health Survey (Gidwani, Tauro, Whitehouse & Newman, 2003; Keurentjes et al., 2013). However, all the prognoses of the patients with total knee are positive. Some patients with total knee replacement show little improvement in the knee functions after the operation (Dickstein, Heffes, Shabtai & Markowitz, 1998) and complain of a decrease in the knee extension torque, range of motion and functional mobility, and a difficulty in carrying out daily functional tasks (Holm, et al., 2010; McClelland, Webster, Feller, & Menz, 2010). Such functional limitations are mainly related with weaknesses of muscle strength of lower extremities so even after the operation, the weakness in the knee extensor and flexor may continue into a few months or even years (Valtonen, Poyhonen, Sipila, & Heinonen, 2010). There are many studies being conducted on the knee function of patients with total knee replacement at various levels, nonetheless, there are too few studies to compare and analyze the knee function of the surgical site, based on whether or not research subjects had total knee replacement (TKR) and whether they had TKR on one or both knees. Therefore, the present study aims to explore the differences in knee function between the subjects who had TKR and those who did not, and between the subjects who had TKR on one knee and those who had on both knees in order to gather underlying information needed to understand the clinical features of patients with TKR.