Osteoarthritis (OA) is the most common form of arthritis worldwide, characterised by the progressive degeneration of joint cartilage and underlying bone, leading to pain, stiffness and functional limitations (Hunter & Bierma-Zeinstra 2019). The prevalence of OA has been increasing in tandem with global trends in ageing populations and rising obesity rates (Safiri et al. 2020). Estimates suggest that approximately 528 million people were living with OA in 2019, an increase of 113% since 1990, making it a leading cause of disability globally (Vos et al. 2020). The burden of OA is not confined to individual suffering but extends to high societal costs, including increased healthcare utilisation and productivity losses (Cross et al. 2014). Historically, the management of OA has focused heavily on pharmacological interventions, such as non-steroidal anti-inflammatory drugs and intra-articular corticosteroid injections, as well as surgical options like joint replacement in advanced cases (Bannuru et al. 2019). While these treatments can offer symptom relief, they do not address the underlying risk factors driving disease progression, nor do they come without side effects and complications (Fernandes et al. 2013). Consequently, there has been a growing recognition of the importance of non-pharmacological approaches, particularly lifestyle interventions, in managing OA holistically and sustainably.

Lifestyle interventions encompass a range of strategies aimed at modifying daily habits and behaviours to improve health outcomes. For individuals with OA, these interventions may include physical activity programmes, weight management, dietary modifications, self-management education and psychological support (Hawker 2019).

Clinical guidelines from major organisations, including the Osteoarthritis Research Society International and the American College of Rheumatology, strongly recommend that core treatments for OA should prioritise patient education and structured exercise alongside weight loss when appropriate (Bannuru et al. 2019). Physical activity, particularly aerobic and strengthening exercises, is consistently identified as a cornerstone of OA management (Fransen et al. 2015). Evidence indicates that exercise reduces pain, improves function and may even delay structural progression (Uthman et al. 2013). Yet, despite its well-established benefits, adherence to exercise regimens among individuals with OA remains suboptimal due to factors such as pain, fear of exacerbating symptoms, a lack of motivation and limited access to tailored programmes (Giardulli et al. 2025).

Weight management is another critical component, especially for individuals with knee and hip OA. Excess body weight increases joint loading, exacerbates pain and accelerates cartilage degeneration (Bliddal, Leeds & Christensen 2014).

Studies have shown that a modest weight reduction of 5% – 10% can significantly decrease pain and improve physical function in overweight or obese individuals with OA (Messier et al. 2013). However, sustainable weight loss requires long-term lifestyle changes, combining dietary modifications with physical activity and behavioural strategies (Christensen et al. 2007). Dietary interventions themselves are gaining attention, not only for their role in weight management but also for their potential anti-inflammatory effects (Méndez & Medina 2021). Diets rich in omega-3 fatty acids, antioxidants and polyphenols have shown promise in reducing OA-related inflammation and pain (Sanghi et al. 2009). However, the evidence base remains fragmented, and more rigorous studies are needed to establish specific dietary recommendations for OA patients. Beyond physical and nutritional aspects, psychological and social factors play a significant role in the lived experience of OA. Chronic pain and disability can lead to depression, anxiety and social isolation, which in turn may hinder engagement in beneficial lifestyle behaviours (Stubbs et al. 2016). Therefore, cognitive behavioural therapy, pain coping skills training and peer support groups are increasingly integrated into comprehensive OA management to address psychosocial barriers and promote self-efficacy (Somers et al. 2012).

Recent developments in knee OA management have emphasised the importance of delivering lifestyle interventions in real-world, patient-centred contexts. Approaches such as shared decision-making and tailoring interventions to individual values, preferences and readiness for change have led to increasingly diverse and adaptive programme designs (Hunter & Bierma-Zeinstra 2019). In parallel, the growing use of digital health strategies, including telerehabilitation and mobile health applications, has further expanded the modes of delivery and accessibility of these interventions (Hinman et al. 2020). While these advances are promising, they contribute to considerable variation in how lifestyle interventions are conceptualised, implemented and evaluated. This heterogeneity underscores the need for a comprehensive synthesis of the range, characteristics and outcome measures of lifestyle interventions for individuals with knee OA, which our scoping review aims to address.

Despite the abundance of individual studies and systematic reviews examining various lifestyle strategies for OA, a comprehensive mapping of the evidence remains necessary to identify gaps and guide future research, policy and practice for knee OA. Scoping reviews offer an effective methodological approach to collate and synthesise heterogeneous evidence, especially when the topic is complex and has not been comprehensively reviewed before (Peters et al. 2020). By systematically exploring the range and nature of lifestyle interventions for individuals with OA, our review aimed to examine the characteristics and components of lifestyle interventions for knee OA and to identify the specific outcome measures used to evaluate their efficacy.

A total of 36 studies met the inclusion criteria for our scoping review, representing a diverse array of research designs including RCTs, quasi-experimental studies, cohort studies, feasibility trials, qualitative studies and narrative reviews. See Table 1 for a full description of the included studies. The included studies were published between 2009 and 2024 and conducted across various geographical regions, including Australia, the United States (US), the United Kingdom (UK), Saudi Arabia, Brazil, Pakistan and Nigeria. Most studies were RCTs with sample sizes ranging from 20 participants to 232 participants. The diversity of study populations and settings underscores a global effort to investigate lifestyle interventions for managing knee OA.

The studies examined a wide range of lifestyle interventions, including exercise therapy, dietary modification, psychological strategies, education and combinations of these modalities. Exercise-based interventions were the most prevalent, including resistance training (Taglietti et al. 2018), aquatic exercise (Carmona-Teres et al. 2015), Tai Chi (Sadeghi et al. 2023) and physiotherapist-led home exercise programmes (Hinman et al. 2020). Dietary interventions included structured weight loss programmes, Mediterranean diets and anti-inflammatory nutrition plans aimed at reducing OA-related symptoms (Messier et al. 2013; Rafiq, Abdul Hamid & Hafiz 2021). Psychological strategies were integrated in several studies, including cognitive behavioural therapy (Somers et al. 2012) and mindfulness-based approaches (Harris et al. 2023). Educational components were either standalone or embedded within multicomponent programmes, often delivered through in-person sessions or digital platforms (Lawford et al. 2023; Smith et al. 2023).

Intervention delivery methods varied considerably. Some programmes were conducted face-to-face in clinical or community settings, while others employed telehealth, mobile applications or online portals. For instance, Lawford et al. (2023) examined a telerehabilitation programme integrating physiotherapy with online education, while Holm et al. (2023) utilised a remotely delivered neuromuscular exercise intervention. Home-based and self-managed models were also reported, such as the digital exercise and education programmes evaluated by Bennell et al. (2017a) and De Rooij et al. (2017). Multidisciplinary teams, including physiotherapists, dietitians and psychologists, were commonly involved in delivering these interventions, particularly in trials combining physical and psychosocial support.

One of the objectives of our review was to identify the outcome measures used to assess these lifestyle interventions. Analysis of the data revealed that no single outcome measure was employed universally across all 36 identified studies. Instead, the authors utilised a broad array of validated tools to capture different dimensions of the disease. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was the most frequently utilised tool for assessing pain and physical function. Other common clinical metrics included the Visual Analogue Scale for pain intensity, the Timed Up and Go (TUG) test for functional mobility and the Knee Injury and Osteoarthritis Outcome Score (KOOS). To measure quality of life and psychosocial impact, studies often employed the Short Form Health Survey (SF-36 or SF-12), the EuroQol-5D and the Pain Catastrophising Scale.

Across the included studies, the majority reported favourable outcomes associated with lifestyle interventions.

Exercise and education programmes consistently improved pain, function and quality of life among individuals with knee OA (Bennell et al. 2022; Taglietti et al. 2018). Multicomponent interventions that combined physical activity with education, psychological support or nutritional counselling yielded greater improvements in outcomes compared to single-modality interventions (Messier et al. 2021; Smith et al. 2023). Furthermore, scalable interventions delivered via telehealth or mobile platforms demonstrated strong potential for accessibility and adherence, especially in contexts where in-person delivery was impractical or resource-limited (Holm et al. 2023; Lawford et al. 2023).

Several studies have also reported barriers to the successful delivery and uptake of interventions. These included limited digital literacy, low motivation or adherence among participants, cultural misalignment of interventions and logistical challenges such as transportation or internet access (Alfieri et al. 2020; Gudbergsen et al. 2021). Conversely, facilitators that enhanced intervention effectiveness included personalised care plans, culturally tailored content, the use of behavioural change techniques and the presence of social or peer support mechanisms (O’Brien et al. 2018; Ojoawo et al. 2024). Studies conducted in low-income and middle-income countries, such as Nigeria and Pakistan, emphasised the importance of culturally relevant and cost-effective programmes to improve feasibility and engagement (Ojoawo et al. 2024; Saleem et al. 2022).

In general, the findings of our scoping review suggest that lifestyle interventions are not only feasible and acceptable but also effective in addressing the multifactorial needs of individuals with knee OA. The results underscore the potential of combining physical, nutritional, psychological and educational components into integrated care pathways to enhance clinical and functional outcomes.

Our scoping review revealed the growing body of evidence supporting multimodal lifestyle interventions as effective strategies for managing knee OA. In our review, lifestyle interventions are defined as structured or semi-structured, non-pharmacological strategies aimed at modifying individuals’ daily behaviours to improve health outcomes in knee OA. These interventions typically target modifiable risk factors and functional limitations through approaches such as physical activity and exercise, weight management, dietary modification, patient education, and behavioural or psychological strategies, including self-management training and cognitive behavioural approaches (Bannuru et al. 2019; Hunter & Bierma-Zeinstra 2019). This definition reflects contemporary models of care that emphasise patient-centred and sustainable approaches to managing knee OA.

Our review synthesised findings from 36 studies, involving 4025 participants, spanning diverse settings and populations, revealing that programmes incorporating multiple lifestyle components, such as exercise, weight management, education, psychological support and behaviour change techniques, were more effective in improving pain, physical function and quality of life compared to single-component interventions (Bennell et al. 2020; Hinman et al. 2020; Messier et al. 2022). The results demonstrate that lifestyle management for knee OA has evolved beyond simple exercise prescriptions. While traditional physiotherapy-guided exercise remains a foundational element, there is a significant trend towards incorporating psychological and educational components. Interventions such as cognitive behavioural therapy, mindfulness-based Tai Chi and pain coping skills training were prominent in the literature. This shift aligns with the biopsychosocial model of chronic pain, suggesting that addressing the psychological burden of OA is as critical as addressing physical dysfunction. The synergistic effect of combining structured exercise with dietary advice and self-management education was repeatedly demonstrated across the studies (Chen et al. 2021; Lawford et al. 2018). Interventions that adopted behavioural coaching models or digitally supported platforms were especially effective in enhancing patient engagement and adherence, a critical determinant of long-term outcomes (Smith et al. 2023; Walrabenstein et al. 2022). These findings align with the biopsychosocial framework of chronic disease management, emphasising that sustained improvements in OA symptoms require addressing biological, behavioural and contextual factors (Loeser et al. 2017). A notable finding is the proliferation of digital health interventions, including mobile apps, tele-physiotherapy and web-based platforms. These models appear to offer clinical benefits comparable to in-person care while providing greater flexibility. However, the identification of ‘digital literacy’ and ‘tech usability’ as recurring barriers suggests that while eHealth increases accessibility for some, it may create new barriers for older populations or those with limited technological proficiency. Considering the diversity of intervention models and populations studied, future research should adopt more standardised, yet simple and pragmatic, outcome measures.

Our review highlights tools such as the TUG test, 30-s sit-to-stand test and patient-reported global rating of change as feasible alternatives to comprehensive instruments like WOMAC and KOOS, particularly for large-scale community or digital trials (Alghadir et al. 2019; Kaufman et al. 2022). Additionally, measures of patient activation and self-efficacy (e.g. Patient Activation Measure [PAM]-13) provide valuable insights into behaviour change, which is crucial for lifestyle modification (Lawford et al. 2023). Adherence to lifestyle interventions emerged as a key determinant of effectiveness across the included studies, with several interrelated factors influencing compliance and participant engagement. Motivation was frequently reported as a central barrier, particularly in programmes requiring sustained behavioural change such as exercise adherence, dietary modification or self-management practices (Giardulli et al. 2025). Additional challenges included limited access to facilities or technology, time constraints, low digital literacy in eHealth-based interventions and variability in individual readiness for change (Ojoawo et al. 2024). Conversely, facilitators of adherence included structured, supervised programmes; personalised or tailored interventions; ongoing coaching or professional support; and the incorporation of social or peer support mechanisms. Interventions described as ‘holistic’ in our study typically referred to multicomponent programmes that combined physical (e.g. exercise therapy), behavioural (e.g. education and self-management strategies) and, in some cases, psychosocial or dietary elements. These integrated approaches appeared to enhance engagement by addressing the multifactorial nature of knee OA and supporting sustained behaviour change. Collectively, these findings highlight that beyond intervention content, the design and delivery context play a critical role in influencing adherence and overall outcomes.

A primary objective of our review was to identify the outcome measures used to evaluate lifestyle interventions in individuals with knee OA. The findings demonstrate considerable heterogeneity, with no single outcome measure consistently applied across all included studies. Although the WOMAC remains the most frequently utilised tool for assessing pain, stiffness and physical function, its continued prominence in recent trials highlights its central role in evaluating clinical outcomes (Ali et al. 2025). Similarly, contemporary interventions continue to incorporate broader outcome domains, including health-related quality of life using the SF-36, which has shown significant responsiveness to lifestyle interventions (Chen et al. 2021), and performance-based measures reflecting functional mobility.

This diversity reflects the multidimensional nature of knee OA and the broad targets of lifestyle interventions, which encompass physical, psychological and behavioural components. Recent evidence confirms that exercise, weight management and combined lifestyle programmes improve pain, physical function and overall well-being, although the magnitude of clinical benefit may vary across settings (Huffman et al. 2024; Landry & Bagha 2026). Moreover, emerging models of care continue to integrate physical activity and behavioural strategies as first-line interventions, reinforcing the need to capture multiple outcome domains (Izquierdo, Ramírez-Vélez & Fiatarone Singh 2025). Despite these advances, methodological challenges persist. The variability in outcome selection limits comparability across studies, complicates evidence synthesis and restricts the feasibility of robust meta-analyses. Wu et al. (2022) highlight the ongoing difficulties in evaluating the effectiveness of interventions due to inconsistent measurement approaches and undefined key outcome dimensions in knee OA research. The findings of this systematic review highlighted the need to develop and adopt a Core Outcome Set (COS) tailored to lifestyle interventions for knee OA. Standardisation of outcome measures would enhance comparability, strengthen evidence synthesis and facilitate translation into clinical practice. Importantly, future COS development should incorporate stakeholder perspectives, including patients and clinicians, to ensure that selected outcomes are meaningful, comprehensive and aligned with real-world care priorities.

Lifestyle interventions for knee OA are diverse and generally effective in improving pain, function and quality of life. However, substantial variability in intervention design and outcome measures limits comparability and evidence synthesis. Standardising outcome assessment through a COS and improving consistency in reporting will strengthen future research and support the translation of lifestyle interventions into clinical practice.