The effect of body mass index and preoperative weight loss in people with obesity on postoperative outcomes to 6 months following total hip or knee arthroplasty: a retrospective study

Abstract Background Few studies have investigated the association between obesity, preoperative weight loss and postoperative outcomes beyond 30- and 90-days post-arthroplasty. This study investigated whether body mass index (BMI) and preoperative weight loss in people with obesity predict postoperative complications and patient-reported outcomes 6 months following total knee or hip arthroplasty. Methods Two independent, prospectively collected datasets of people undergoing primary total knee or hip arthroplasty for osteoarthritis between January 2013 and June 2018 at two public hospitals were merged. First, the sample was grouped into BMI categories, < 35 kg/m2 and ≥ 35 kg/m2. Subgroup analysis was completed separately for hips and knees. Second, a sample of people with BMI ≥ 30 kg/m2 was stratified into participants who did or did not lose ≥ 5% of their baseline weight preoperatively. The presence of postoperative complications, Oxford Hip Score, Oxford Knee Score, EuroQol Visual Analogue Scale and patient-rated improvement 6 months post-surgery were compared using unadjusted and adjusted techniques. Results From 3,552 and 9,562 patients identified from the datasets, 1,337 were included in the analysis after merging. After adjustment for covariates, there was no difference in postoperative complication rate to 6 months post-surgery according to BMI category (OR 1.0, 95%CI 0.8–1.4, P = 0.8) or preoperative weight loss (OR 1.1, 95%CI 0.7–1.8, P = 0.7). There was no between-group difference according to BMI or preoperative weight change for any patient-reported outcomes 6 months post-surgery. Conclusion Preoperative BMI or a 5% reduction in preoperative BMI in people with obesity was not associated with postoperative outcomes to 6 months following total knee or hip arthroplasty

A mixed methods approach to investigating physical activity in people with obesity participating in a chronic care programme awaiting total knee or hip arthroplasty

Aims: To describe patient-reported physical activity and step count trajectory and explore perceived barriers and enablers to physical activity amongst people with obesity participating in a chronic care programme whilst awaiting arthroplasty. Design: Convergent parallel mixed-method study. Method: A patient cohort derived from a longitudinal sample of adults with end-stage osteoarthritis and obesity from a chronic care programme whilst awaiting primary total knee or hip arthroplasty (n = 97) was studied. Physical activity was measured at baseline (entry to the wait list) and before surgery (9–12 months waiting time) using the Lower Extremity Activity Scale (LEAS) and activity monitors (activPAL™). A subset of participants completed in-depth semi-structured interviews 6 months after being waitlisted to explore perceived barriers and enablers to physical activity. Themes were inductively derived and then interpreted through the COM-B model. Results: Baseline LEAS and activPAL™ data were available from 97 and 63 participants, respectively. The proportion of community ambulant individuals reduced from 43% (95% CI 33%–53%) at baseline to 17% (95% CI 9%–28%) pre-surgery. Paired activPAL™ data (n = 31) for step count, upright time, and stepping time remained unchanged. Twenty-five participants were interviewed. Five themes underpinning physical activity were mapped to the COM-B model components of capability (physical capability), opportunity (accessibility and social norms), and motivation (self-efficacy and beliefs and physical activity). Conclusions: Participation in a chronic care programme did not improve physical activity levels for people with obesity awaiting arthroplasty. Programs cognisant of the COM-B model components may be required to address the natural trajectory of declining physical activity levels while awaiting arthroplasty

Why do some people with osteoarthritis and obesity awaiting hip or knee arthroplasty achieve successful weight management? A qualitative study

Aim: To explore perceived barriers and enablers to weight management among people with obesity awaiting total knee or hip arthroplasty. Design: A nested qualitative study within a multi-centre, quasi-experimental pilot study comparing usual care weight management to a dietitian-led weight-loss diet. Methods: Semi-structured individual interviews were conducted with adults with end-stage osteoarthritis and a body mass index ≥30 kg/m2 waitlisted for primary total knee or hip arthroplasty. Participants with diverse sociodemographic characteristics and varied success with weight management in the pilot study were purposively sampled. Interviews were analysed using inductive thematic analysis, underpinned by constructivist–interpretivist epistemology. The Patient Activation Measure and Health Literacy Questionnaire were used for context when interpreting the findings. Results: Twenty-five participant interviews were conducted with a sociodemographically varied sample (aged 44–80 years, 9 born in Australia, 6 in paid employment and 11 lost ≥5% of their baseline weight). Four identified themes underpinned successful weight management: beliefs, adaptability, navigating healthcare and sociocultural context. Beliefs about whether weight was perceived as a problem, the expectation of weight loss and treatment-related beliefs influenced participants\u27 perspectives towards weight loss. Adaptability, the ability to overcome barriers to weight loss, comprised three subthemes; readiness to act, degree of independence and problem-solving skills. Approaches towards navigating healthcare influenced uptake and adherence to weight management recommendations. Importantly, these themes were dependent on social and environmental circumstances, which influenced the type of barriers experienced and resources available to the individual. Conclusion: Differences in a person\u27s beliefs, their ability to adapt and navigate healthcare and sociocultural context appear to explain successful weight management among people with end-stage arthritis. Implications for the profession and/or patient care: Clinicians should allow for individualisation cognisant of the identified themes when providing advice and treatment to promote adherence to weight management interventions. Impact: This study explored perceived barriers and enablers to weight management among people with obesity awaiting total knee or hip arthroplasty. Four identified themes underpinned successful weight management: beliefs, adaptability, navigating healthcare and sociocultural context. Beliefs about whether weight was perceived as a problem, the expectation of weight loss and treatment-related beliefs influenced participants\u27 perspectives towards weight loss. Understanding and assessing the contribution of each factor may guide weight management from clinicians treating patients with obesity and osteoarthritis. Reporting Method: The data are reported using the COREQ guidelines. Patient or Public Contribution: Patients contributed to the data collected

Patients\u27 experiences of subacute pain management following total hip or knee arthroplasty: A qualitative study

Background: Total hip and knee arthroplasties are common surgeries performed worldwide, but the management of pain during the subacute period (defined as hospital discharge to 3 months postoperatively) is poorly understood. This study aimed to determine patients\u27 experiences, facilitators and barriers to subacute pain management following total hip or knee arthroplasty. Methods: Semi-structured interviews with a purposive sample of patients following total hip or knee arthroplasty were conducted between June and August 2022. Participants were recruited from two tertiary metropolitan hospitals. Interviews were audio-recorded and transcribed verbatim. Data were analysed using an inductive thematic approach to identify common themes. Results: In total, 30 interviews were conducted with patients following hip or knee arthroplasty. Four main themes were identified: (i) Physical constitution before surgery (joint condition, analgesic use, age, and hearing); (ii) Attitude and knowledge (motivation, outlook on life, attitude towards taking medications, individual benchmarking, and knowledge); (iii) Socio-ethno-cultural factors (family and community connection, language, and religion), and (iv) Health-system support (health-professional delivered education, medications, services, staff, and costs). Conclusions: Participants\u27 experiences of subacute pain following hip or knee arthroplasty were shaped by multidimensional factors. Strategies to empower patients through increased education and support during postoperative opioid tapering as well as a shift to a biopsychosocial approach to pain management during the subacute period may improve patient and health-system outcomes