Abstract
Sarcopenic obesity is closely associated with knee osteoarthritis (KOA) and has high risk of total knee replacement (TKR). In addition, poor nutrition status may lead to sarcopenia and physical frailty in KOA and is negatively associated with surgery outcome after TKR. This study investigated the effects of sarcopenic obesity and its confounding factors on recovery in range of motion (ROM) after total knee replacement (TKR) in older adults with KOA. A total of 587 older adults, aged ≥60 years, who had a diagnosis of KOA and underwent TKR, were enrolled in this retrospective cohort study. Sarcopenia and obesity were defined based on cutoff values of appendicular mass index and body mass index for Asian people. Based on the sarcopenia and obesity definitions, patients were classified into three body-composition groups before TKR: sarcopenic-obese, obese, and non-obese. All patients were asked to attend postoperative outpatient follow-up admissions. Knee flexion ROM was measured before and after surgery. A ROM cutoff of 125 degrees was used to identify poor recovery post-surgery. Kaplan-Meier curve analysis was performed to measure the probability of poor ROM recovery among study groups. Cox multivariate regression models were established to calculate the hazard ratios (HRs) of postoperative poor ROM recovery, using potential confounding factors including age, sex, comorbidity, risk of malnutrition, preoperative ROM, and outpatient follow-up duration as covariates. Analyses results showed that patients in the obese and sarcopenic-obese groups had a higher probability of poor ROM recovery compared to the non-obese group (all p < 0.001). Among all body-composition groups, the sarcopenic-obese group yielded the highest risk of postoperative physical difficulty (adjusted HR = 1.63, p = 0.03), independent to the potential confounding factors. Sarcopenic obesity is likely at the high risk of poor ROM outcome following TKR in older individuals with KOA.
Highlights
Obesity has become epidemic worldwide in populations with knee osteoarthritis (KOA) and has growing impacts for those who are undergoing total knee replacement (TKR) [1]
Due to the fact that the rate of TKR grows rapidly in obese older individuals with KOA [16,17] and that the postoperative range of motion (ROM) gains are significantly associated with function recovery [12,18,19,20,21], there is an urgent need to further identify the effect of obesity on ROM recovery following TKR
Between the sarcopenic obesity and non-obesity groups, the mean values of comorbidity score (10.9 versus 8.4 points), number of patients who were at risk of undernutrition (27/59 versus 76/205), preoperative (101 versus 118 degrees) and inpatient-discharge (94 versus 102 degrees) knee flexion ROMs, length of inpatient stay (LOS) (6.2 versus 5.3 days), and outpatient follow-up duration (19.5 versus 13.7 weeks) differed significantly; similar results were observed between the obesity and non-obesity groups
Summary
Obesity has become epidemic worldwide in populations with knee osteoarthritis (KOA) and has growing impacts for those who are undergoing total knee replacement (TKR) [1]. Obesity is a predominant risk factor for post-surgery complications and may affect short-term or long-term outcomes after TKR [7,8], among which the recovery in knee flexion range of motion (ROM) is of particular interest [9,10,11,12,13]. A number of previous studies have indicated that obesity negatively affects ROM recovery following TKR [7,14], whereas others had inconsistent conclusions [15]. Due to the fact that the rate of TKR grows rapidly in obese older individuals with KOA [16,17] and that the postoperative ROM gains are significantly associated with function recovery [12,18,19,20,21], there is an urgent need to further identify the effect of obesity on ROM recovery following TKR
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
