Is Kinesiophobia Associated With Quality of Life, Level of Physical Activity, and Function in Older Adults With Knee Osteoarthritis?

Abstract

Background

Beyond knee pain itself, the fear of movement, also known as kinesiophobia, recently has been proposed as a potential factor contributing to disability and functional limitation in patients with knee osteoarthritis (OA). Nevertheless, the available evidence on the association of kinesiophobia with patient-reported outcome measures (PROMs) in knee OA remains limited.

Questions/purposes

Among patients with nonoperatively treated knee OA, we asked: (1) Is kinesiophobia associated with decreased quality of life (QoL), functional outcomes, and physical activity? (2) What are the patient disease and psychosocial demographic factors associated with kinesiophobia?

Methods

This was a multicenter, cross-sectional study of 406 general orthopaedic patients from two urban, referral-based tertiary hospitals in Singapore under a single healthcare group who received nonoperative treatment for knee OA. Between July 2020 and January 2022, a total of 1541 patients were treated for knee OA nonoperatively. Based on that, 60% (923) of patients were rejected due to refusal to participate in the study, 3% (52) of patients were enrolled but did not show up for their appointments for data collection, and a further 10% (160) had incomplete data sets, leaving 26% (406) for this study’s analysis. The mean age of patients was 64 ± 8 years, 69% were women, and 81% were Chinese. The level of kinesiophobia in patients was measured using the Brief Fear of Movement scale, a validated 6-item questionnaire ranging from a score of 6 to 24 to measure kinesiophobia in OA, with higher scores representing higher levels of kinesiophobia. In terms of PROMs, the QoL and functional level of patients were measured using the QoL and activities of daily living (ADL) components of the widely validated 12-item Knee Injury and Osteoarthritis Outcome Score (KOOS-12). The KOOS-12 is a questionnaire consisting of 12 items encompassing three domains (QoL, ADL, and pain), with each item ranging from 0 to 4 and higher scores representing worse outcomes. The University of California, Los Angeles (UCLA) Activity Scale was used to measure the level of physical activity in patients. The UCLA score is a descriptive 10-level activity scale ranging from a score of 1 to 10, with higher scores representing greater physical activity levels. A directed acyclic graph, which is a relationship map used to depict and visualize the confounders between the studied variables, was used to identify the confounders between kinesiophobia and PROMs (QoL, function, and physical activity). An ordinal regression model was used to explore: (1) the association between kinesiophobia (as measured using the Brief Fear of Movement scale) and PROMs (as measured using KOOS QoL, KOOS ADL, and the UCLA Activity Scale), adjusting for key confounders such as age, gender, pain, side of arthritis, OA duration/severity, and psychosocial factors (for example, depression, anxiety, and education levels), and (2) the association between kinesiophobia (Brief Fear of Movement scale) and various patient disease and psychosocial demographic factors.

Results

After accounting for confounders, greater kinesiophobia (higher Brief Fear of Movement scores) was associated with lower QoL (KOOS QoL score adjusted IQR OR 0.69 [95% confidence interval (CI) 0.53 to 0.90]; p = 0.007) and lower physical activity (UCLA score adjusted IQR OR 0.68 [95% CI 0.52 to 0.90]; p = 0.007); however, there was no association between kinesiophobia and function (KOOS ADL score adjusted IQR OR 0.90 [95% CI 0.70 to 1.17]; p = 0.45). After adjusting for age, gender, OA duration, pain, and BMI, higher levels of anxiety (Patient Health Questionnaire 2 [PHQ-2] anxiety score adjusted OR 2.49 [95% CI 1.36 to 4.58]; p = 0.003) and depression (PHQ-2 depression score adjusted OR 3.38 [95% CI 1.73 to 6.62]; p < 0.001) were associated with higher levels of kinesiophobia. Education level, OA disease severity, side of arthritis (unilateral versus bilateral), and history of previous injury or surgery on the knee were not associated with kinesiophobia.

Conclusion

Clinicians should assess for kinesiophobia and other psychological comorbidities such as depression and anxiety at the point of initial evaluation and subsequent follow-up of knee OA with simple validated tools like the Brief Fear of Movement scale (kinesiophobia) in the clinic. This allows for clinicians to identify high-risk individuals and offer evidence-based treatment such as cognitive behavioral therapies with a multidisciplinary team, including a physical therapist and psychologist, to manage these psychological comorbidities and improve outcomes in patients with knee OA. While kinesiophobia was found to be associated with poorer QoL and physical activity, future studies including larger observational cohort studies should be conducted to determine causal and prognostic relationships between kinesiophobia and outcomes in knee OA.

Level of Evidence

Level III, prognostic study.

Introduction

Kinesiophobia is defined as “an excessive, irrational, and debilitating fear of physical movement and activity resulting from a feeling of vulnerability because of painful injury or reinjury” [25]. Kinesiophobia has been reported to be associated with poorer clinical outcomes, disability, and quality of life (QoL) in musculoskeletal diseases [36]. The fear-avoidance model has been proposed as a theory explaining how kinesiophobia impacts disability, recovery, and outcomes in chronic pain conditions such as knee osteoarthritis (OA) [46]. This model proposes that patients who experience pain would follow one of two paths: (1) either the path of “no fear,” which leads to confrontation and actions to overcome the underlying pain and eventually recovery, or (2) the path of “pain catastrophizing,” which leads to pain-related fear (including kinesiophobia), avoidance hypervigilance, increased disuse, and disability that leads to worsening of their condition and greater pain—a vicious cycle involving pain, fear, and disability [46].

Although more studies are reporting the importance of considering psychosocial factors in OA management, there remains a lack of evidence examining the relationship between kinesiophobia and patient-reported outcome measures (PROMs) in knee OA specifically [24, 49]. Previous studies that touched on the association between kinesiophobia and knee OA outcomes largely consisted of small cross-sectional studies [2, 5]. Moreover, when considering the relationship between kinesiophobia and knee OA outcomes, the current available evidence also does not fully account for multiple interplaying demographic, disease, and psychosocial factors that could potentially confound the relationship [14]. Kinesiophobia is a potentially modifiable psychological factor that could serve as a target for optimizing treatment of knee OA. Nevertheless, there remains a gap in the current evidence studying the association between kinesiophobia and outcomes of knee OA. Without stronger evidence establishing the relationship between kinesiophobia and knee OA outcomes, further discussion of the clinical benefits and applicability of addressing kinesiophobia as a potential modifiable factor in the treatment of knee OA is limited. Therefore, further exploration to clarify the relationship between kinesiophobia and knee OA outcomes in a larger sample size with a better account of confounding factors is warranted.

Among patients with nonoperatively treated knee OA, we therefore asked: (1) Is kinesiophobia associated with decreased QoL, functional outcomes, and physical activity? (2) What are the patient disease and psychosocial demographics factors associated with kinesiophobia?

Materials and Methods

Study Design and Setting

This was a multicenter, cross-sectional study of 406 general orthopaedic patients from two urban, referral-based tertiary hospitals in Singapore under a single healthcare group who received nonoperative treatment for knee OA as part of the baseline data collected for a multicenter, prospective cohort study for knee OA [39]. Between July 2020 and January 2022, a total of 1541 patients were treated for knee OA nonoperatively. Based on that figure, 60% (923) of patients were rejected due to refusal to participate in the study, 3% (52) of patients were enrolled but did not show up for their appointments for data collection, and a further 10% (160) had incomplete data sets, leaving 26% (406) for this study’s analysis. Results were reported in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines [11].

Participants

This study included 406 patients who presented to two tertiary hospitals between July 2020 to January 2022. Patients were independently community ambulant (without or with walking aids) and met the National Institute for Health Care Excellence clinical diagnostic criteria for knee OA (≥ 45 years of age, presence of joint pain related to activity, and the absence of joint-related morning stiffness lasting > 30 minutes) [30]. Patients with secondary arthritis (such as inflammatory arthritis), patients with an alternative diagnosis for their knee symptoms (including spine or hip referred pain), those who had previous knee arthroplasty or medical comorbidities severely impairing activities of daily living (ADL; for example, heart failure with poor effort tolerance, previous stroke, cognitive impairment), and those who used wheelchairs were excluded from the study.

Descriptive Data

We collected the baseline demographic characteristics of patients, including age, gender, ethnicity, education level, side of arthritis (unilateral versus bilateral), BMI, disease severity (Kellgren-Lawrence grade), history of previous injuries, and duration of knee OA symptoms. The mean age of patients was 64 ± 8 years, and 69% of patients were women. The mean BMI of patients was 26 ± 6 kg/m², and the mean duration of OA symptoms was 5 ± 5 years. The mean ± SD Brief Fear of Movement score for patients was 9 ± 4, and the mean Patient Health Questionnaire 4 (PHQ-4) score was 2 ± 3. The mean KOOS pain score was 64 ± 17, the KOOS ADL score was 73 ± 19, and the KOOS QoL score was 55 ± 19 (Table 1).

Table 1.

Descriptive statistics on demographic characteristics (n = 406)

Characteristic	Total
Age in years	64 ± 8
Men	31 (125)
Ethnicity
Chinese	81 (328)
Malay	7 (30)
Indian	10 (41)
Others	2 (7)
BMI in kg/m2	26 ± 6
Duration of OA symptoms in years	5 ± 5
Educational level
No or minimal education/up to elementary	21 (86)
Up to secondary school/high school	46 (185)
University and above	32 (131)
Others	1 (4)
Side of arthritis
Bilateral	45 (183)
Disease severity
Kellgren-Lawrence 2	24 (99)
Kellgren-Lawrence 3	48 (195)
Kellgren-Lawrence 4	18 (73)
History of previous injury	21 (86)
History of previous surgery	6 (23)
Brief Fear of Movement score (kinesiophobia)	9 ± 4
PHQ-2 anxiety score (≥ 3)	10 (42)
PHQ-2 depression score (≥ 3)	8 (33)
PHQ-4 score	2 ± 3
KOOS pain score	64 ± 17
KOOS ADL score	73 ± 19
KOOS QoL score	55 ± 19
KOOS score total	65 ± 16

Data presented as mean ± SD or % (n).

Kinesiophobia

The Tampa Scale of Kinesiophobia (TSK) is a widely validated 17-item questionnaire used as a tool for measuring the kinesiophobia level in patients experiencing musculoskeletal pain [16]. However, the applicability and validity of the TSK in OA remains controversial [37]. The Brief Fear of Movement scale is a more concise and targeted tool to measure kinesiophobia validated in patients with OA, focusing on 6 of 17 items that comprise the TSK [37]. Six questions assessing the level of kinesiophobia are included in the Brief Fear of Movement scale, as described by Shelby et al. [37], each measured on a 4-point scale (strongly disagree, disagree, agree, strongly agree) and forming a scale range of 6 to 24, with higher score indicating higher levels of kinesiophobia. In this study, kinesiophobia was measured using the Brief Fear of Movement scale. There is currently no validated study describing the cutoff scores to differentiate between high or low levels of kinesiophobia for the Brief Fear of Movement scale. However, it has been reported that a score of > 37 (54% [37 of 68]) for the TSK denotes a high level of kinesiophobia [43]. As the Brief Fear of Movement scale was derived from the TSK, by extrapolation, we have defined a high level of kinesiophobia as a score of > 13 (54% [13 of 24]) on the Brief Fear of Movement scale. A Brief Fear of Movement score of > 13 is equivalent to 88% of the items in the Brief Fear of Movement scale having a score of ≥ 3, which is congruent with results from a recent study by Gunn et al. [22], which also concurred that respondent agreement of ≥ 3 items in the Brief Fear of Movement scale represented a high level of kinesiophobia. In our study population, 13% of patients were reported to have high levels of kinesiophobia based on the Brief Fear of Movement scale (Fig. 1). An empirical cumulative distribution function curve was used to depict the distribution of Brief Fear of Movement scores in our study population (Fig. 1).

Fig. 1.

This empirical cumulative distribution function plot depicts the proportion of patients versus Brief Fear of Movement score (level of kinesiophobia).

PROMs

PROMs, including the widely validated 12-item Knee Injury and Osteoarthritis Outcome Score (KOOS-12) and UCLA activity score were measured for patients [34, 50]. The KOOS-12 is a questionnaire consisting of 12 items encompassing three domains (pain, ADL, and QoL), which measures the patient’s own perception of their knee function. Each item is ranked between a score of 0 and 4, with four items for each domain and higher scores representing better outcomes [34]. The UCLA Activity Scale is a validated tool that measures the self-reported physical activity level of patients based on a descriptive 10-level scale ranging from a score of 1 to 10, with higher scores representing greater physical activity levels [50]. For this study, we measured QoL, function, and pain with the three components of the KOOS-12: KOOS QoL score, KOOS ADL score, and KOOS pain score, respectively. The level of physical activity of patients was measured using the UCLA score. KOOS-12 and UCLA questionnaires validated in English and Chinese were administered to the participants [10, 48].

Depression and Anxiety

The PHQ-4 is a brief 4-item questionnaire used to screen and evaluate the level of depression and anxiety of patients [28]. Of the four items, two each evaluate the level of anxiety and depression, respectively. Each item is scored as normal (0 to 2), mild (3 to 5), moderate (6 to 8), or severe (9 to 12). A total score of ≥ 3 for the first two items combined (PHQ-2 anxiety score) suggests clinically significant anxiety, and a total score of ≥ 3 for the last two items combined (PHQ-2 depression score) suggests depression [28].

Key Confounders

The current available evidence exploring the relationship between kinesiophobia and PROMs did not fully account for the multiple and interplaying demographic, disease, and psychosocial factors that could potentially confound the relationship [2, 5]. Our study identified the potential key confounders using a directed acyclic graph that visualized the associations between kinesiophobia, the studied factors (QoL, function, and physical activity), and the identified confounding variables [14, 38] (Fig. 2). Age, gender, BMI, OA duration, education level, side of arthritis (unilateral versus bilateral), psychological comorbidities (PHQ-2 anxiety score, PHQ-2 depression score), pain (KOOS pain score), and disease severity (Kellgren-Lawrence grade) were key confounding factors identified from the evidence [1, 3, 8, 19, 21, 32, 33, 40, 52]. Of note, knee pain was a key confounder in the relationship between kinesiophobia and patient-reported outcomes that was not accounted for in the analysis of previous studies, although pain in itself is a well-established independent driver of poorer outcomes in knee OA [2, 5, 31].

Fig. 2.

Directed acyclic graph depicting the relationships and confounders between kinesiophobia, QoL, and functional outcomes in knee OA.

Sample Size Calculation

In this study, our primary aim was to determine the association between Brief Fear of Movement score and QoL and function, as measured using the KOOS QoL and KOOS ADL scores, respectively, and physical activity, as measured using the UCLA score. Multiple regression was used to study the association between the one tested independent variable (Brief Fear of Movement Score) and the study outcomes (QoL, function, physical activity), with control of the 10 confounding factors. With a Type I error of 0.05 and 90% study power, the study needed to recruit a total of 366 patients to detect a relationship between the independent and outcome variables with an effect size of 0.03. The final sample, accounting for a 10% attrition rate, was 406 patients.

Ethical Approval

Ethical approval for this study was obtained from the National Healthcare Group Domain Specific Review Board (reference number WHC/2020-00076).

Statistical Analysis

For continuous variables, we used mean ± SD and median (IQR), and we used frequency (number) for categorical variables. The distribution of the Brief Fear of Movement scores was described graphically using an empirical cumulative distribution plot (Fig. 1).

We used an ordinal regression model to explore the association between Brief Fear of Movement score and PROMs (KOOS QoL and ADL scores and UCLA score), adjusting for the key confounders including age, gender, BMI, OA duration, education levels, side of arthritis, psychological comorbidities (PHQ-2 anxiety score, PHQ-2 depression score), pain (KOOS pain score), and disease severity (Kellgren-Lawrence grade). The OR was scaled to an IQR increase to allow us to standardize and compare the effect of Brief Fear of Movement score on the outcomes. The association between Brief Fear of Movement score and factors including patient disease (side of arthritis, disease severity, history of previous knee injuries, previous knee surgery) and psychosocial demographic characteristics (gender, ethnicity, education, depression, anxiety) was also explored using the ordinal regression model, adjusting for age, OA duration, pain (KOOS pain score), and BMI to remove the confounding effects of these factors, which have been shown to have established associations with kinesiophobia [29, 42]. An ordinal regression model was used instead of a linear regression model due to the violation of assumptions for the linear regression. Multicollinearity was assessed using variance inflation factor, where a factor of < 10 suggested no multicollinearity issues in the model. The goodness of fit of the proportional odds regression model was tested using an ordinal version of the Hosmer Lemeshow goodness-of-fit test, with a p value > 0.05 indicating model fit [17, 18]. Statistical significance was denoted as p < 0.05.

Results

Kinesiophobia and PROMs

After accounting for confounders, greater kinesiophobia (higher Brief Fear of Movement scores) was associated with lower QoL (KOOS QoL score adjusted IQR OR 0.69 [95% confidence interval (CI) 0.53 to 0.90]; p = 0.007) and lower physical activity (UCLA score adjusted IQR OR 0.68 [95% CI 0.52 to 0.90]; p = 0.007); however, there was no association between kinesiophobia and function (KOOS ADL score adjusted IQR OR 0.90 [95% CI 0.70 to 1.17]; p = 0.45).

Factors Associated With Kinesiophobia

After adjusting for age, gender, OA duration, pain, and BMI, higher levels of anxiety (PHQ-2 anxiety score adjusted OR 2.49 [95% CI 1.36 to 4.58]; p = 0.003) and depression (PHQ-2 depression score adjusted OR 3.38 [95% CI 1.73 to 6.62]; p < 0.001) were associated with higher levels of kinesiophobia (Table 2). Education level, OA disease severity, side of arthritis (unilateral versus bilateral), and history of previous injury or surgery on the knee were not associated with kinesiophobia.

Table 2.

Association of Brief Fear of Movement score with disease-related and psychosocial patient factors

	Adjusted OR (95% CI)a	p value	Ordinal HL p value
Gender
Male	Ref.		0.42
Female	1.26 (0.87 to 1.84)	0.22
Ethnicity
Chinese	Ref.		0.18
Malay	0.97 (0.47 to 1.99)	0.92
Indian	0.67 (-0.35 to 1.27)	0.21
Other	0.59 (0.17 to 2.05)	0.40
Education
No or minimal education	Ref.		0.29
Up to secondary school	0.83 (0.52 to 1.30)	0.41
University education and above	0.97 (0.59 to 1.61)	0.92
Side of arthritis
Unilateral	Ref.		0.36
Bilateral	1.41 (0.99 to 2.02)	0.06
Kellgren-Lawrence grade
2	Ref.		0.72
3	1.08 (0.70 to 1.65)	0.74
4	1.25 (0.72 to 2.17)	0.43
Previous injury
No	Ref.		0.92
Yes	1.18 (0.77 to 1.81)	0.44
Previous surgery
No	Ref.		0.75
Yes	0.58 (0.26 to 1.29)	0.18
PHQ-2 anxiety score
No	Ref.		0.86
Yes	2.49 (1.36 to 4.58)	0.003
PHQ-2 depression score
No	Ref.		0.98
Yes	3.38 (1.73 to 6.62)	< 0.001

HL = Hosmer Lemeshow goodness-of-fit test; ref. = reference group.

^aAdjusted for age, duration of OA, pain (KOOS pain score), and BMI.

Discussion

Kinesiophobia has been reported to be associated with poorer clinical outcomes, disability, and QoL in musculoskeletal diseases, with patients with a tendency for pain catastrophizing going down a path which leads to pain-related fear (including kinesiophobia), avoidance hypervigilance, increased disuse, and disability that leads to worsening of their condition and greater pain [36, 46]. Nevertheless, there remains a gap in current literature studying the association between kinesiophobia and outcomes of knee OA after accounting for the potential confounders. We therefore asked, among patients with nonoperatively treated knee OA: (1) Is kinesiophobia associated with decreased QoL, functional outcomes, and physical activity? (2) What are the patient disease and psychosocial demographics factors associated with kinesiophobia? Overall, after adjusting for potential confounders, we found that greater kinesiophobia (measured using the Brief Fear of Movement scale) was associated with lower QoL and lower physical activity (Fig. 2). We also found that greater kinesiophobia was associated with the presence of psychological comorbidities, including anxiety and depression, and was independent of disease factors like disease severity, history of knee injury or surgeries, and the patient’s sociocultural background, including ethnicity and education level. Clinicians should be cognizant of the negative association of kinesiophobia with knee OA outcomes and incorporate routine psychological screening for kinesiophobia and other psychological comorbidities (depression, anxiety) as part of the consultation. This would allow clinicians to identify high-risk individuals and offer evidence-based treatment (for example, graded exposure to movement, pain neuroscience education, cognitive behavioral therapy) in managing these psychological comorbidities and potentially improve outcomes in patients with knee OA [9, 12, 27, 35, 41, 47, 51].

Limitations

This study has several limitations. First, because of its cross-sectional study design, the association found between kinesiophobia and knee OA outcomes cannot be used to determine causality between the two factors. Similarly, while depression and anxiety may predispose a patient to greater kinesiophobia, increased depression or anxiety and activity limitations (related or not related to kinesiophobia) can also cause increased depression or anxiety given the common negative mindsets that underpin these psychological states. Future well-powered, prospective cohort studies that adequately adjust for the confounders such as the ones listed in the present study could be conducted to further explore the causal relationships between the studied factors. Moreover, because of the nature of our study design (cross-sectional), which may be prone to greater selection bias, the prevalence of (high) kinesiophobia found in our population may not fully represent its true prevalence in the population [45]. Last, our study participants were predominantly Asian (mostly of Chinese ethnicity), which may affect the generalizability of results [49]. Future large-scale studies can aim to further explore the relationship of kinesiophobia and knee OA outcomes on different population groups.

Kinesiophobia and PROMs

Overall, our study found that kinesiophobia (measured using the Brief Fear of Movement scale) was associated with lower QoL and physical activity in patients with knee OA. Our findings show that beyond traditional biomedical factors like radiographic severity, kinesiophobia is a key factor that should be considered in the screening and treatment of patients with knee OA to potentially improve clinical outcomes for patients. Kinesiophobia may stem from catastrophic thoughts when an individual encounters pain that perpetuates pain-related fear leading to avoidance behavior [20, 44]. Greater avoidance of physical activity that leads to pain because of the fear-avoidance response would then result in further functional limitation on activities of daily living, weight gain, and muscle atrophy [20, 44]. This can then potentiate greater disability and disease progression that leads to greater pain and poorer QoL, creating a vicious loop that is described by the fear-avoidance model [20, 44, 46]. Furthermore, in line with previous studies, we found that kinesiophobia was associated with lower physical activity levels, which potentially affects participation and effectiveness of physiotherapy and rehabilitation interventions, which are cornerstones of knee OA management [13].

Factors Associated With Kinesiophobia

Moreover, our findings suggest that kinesiophobia is associated with psychological comorbidities, including anxiety and depression, but independent of other disease-related and sociocultural factors such as disease severity, education level, and history of previous injuries. Our findings highlight the interconnectedness of psychological comorbidities, and clinicians should avoid managing these psychological factors in isolation; instead they should aim to target mental health and addressing the negative mindsets (such as pain catastrophizing) that underpin these psychological conditions as a whole in the holistic treatment of knee OA to improve outcomes. Depression, anxiety, and kinesiophobia overlap conceptually in terms of their negative mindsets, which involve higher perceived pain, disability, and chronicity that perpetuate negative mood and fears in the treatment of chronic pain conditions such as knee OA [5, 6]. Depression can result in unhelpful beliefs and perceptions about one’s capability that may exacerbate an elevated sense of fear of movement in patients with knee OA, as they are more prone to viewing movement as increasingly difficult or uncomfortable [26]. Furthermore, it has also been proposed that there are neurobiologic pathways that link depression to increased pain sensitivity, which can further perpetuate a patient’s sense of fear of movement-aggravated pain in knee OA [23]. On the other hand, anxiety results in a sense of heightened hypervigilance and hyperawareness of bodily experiences, which can deter patients from activities that are uncomfortable and painful, such as movement of an osteoarthritic joint, thus perpetuating the kinesiophobia and movement-related anxiety in patients and forming a vicious cycle [4]. This is further in line with recent studies on other chronic diseases that have also shown that treatment of anxiety and depression improves kinesiophobia and vice versa [4, 7, 15].

Conclusion

Our study found that kinesiophobia was independently associated with poorer QoL and physical activity in patients with knee OA after accounting for potential confounding factors. Moreover, kinesiophobia was associated with psychological comorbidities, including depression and anxiety, but independent of disease factors like disease severity, history of knee injury or surgeries, and the patient’s sociocultural background, including ethnicity and education level. Clinicians should incorporate routine psychological screening of kinesiophobia using simple validated questionnaires such as the Brief Fear of Movement scale and other PROMs for psychological comorbidities, such as depression and anxiety (for example, the PHQ-4 questionnaire), as part of clinical consultation. This information would allow clinicians to better stratify high-risk populations for prognostication and initiating treatment to manage kinesiophobia and other psychological comorbidities in patients with knee OA. Clinicians can effectively target kinesiophobia as a modifiable factor in the management of knee OA through evidence-based treatment involving a multidisciplinary approach with psychologists and physical therapists (for example, graded exposure to movement, pain neuroscience education, cognitive behavioral therapy) as part of routine clinical practice. Future observational studies could be conducted to examine kinesiophobia as a prognostic factor in knee OA outcomes. Further studies could also be conducted to validate a clinically significant cutoff score for kinesiophobia measured using the Brief Fear of Movement scale, together with more randomized controlled trials performed to identify effective therapies that reduce kinesiophobia and improve outcomes in knee OA.