Introduction: Foot health and lower extremity function are important in older people with rheumatoid arthritis (RA), as they maintain and promote these individuals’ independent living and functional health. RA is a long-term inflammatory health condition that alters foot structure and function. Relatively little is known about the association between foot health and lower extremity function in older people with RA. Therefore, the aim of the study was to analyse the levels of foot health and lower extremity function in older people with RA and to explore the associations between these factors. Methods: A cross-sectional survey design study was conducted. The data were collected online in April 2023 from a national association of patients with rheumatic conditions in Finland using two instruments: the Self-administered Foot Health Assessment Instrument (S-FHAI) and the Lower Extremity Function Scale (LEFS). The data were analysed using descriptive and inferential statistics. Results: Older people with RA (n = 270) reported many foot health problems, the most common of which were foot pain, dry skin, and oedema. Lower extremity function in older people with RA was at the mild-to-moderate functional limitation level and respondents reported major difficulties running or hopping, squatting, carrying out their usual hobbies, performing strenuous activities outside their homes or putting on shoes/socks. Poor levels of foot health were correlated with decreased lower extremity function. Conclusion: Foot health is associated with lower extremity function in older people with RA. Therefore, it is essential that older people with RA be provided with systematic foot health assessments, care and rehabilitation to promote their lower extremity health and improve their functional health. Multiprofessional collaboration and seamless care chains at different levels of health care could benefit older people with RA looking to maintain their functional ability and – above all – promote their active ageing.

The World Health Organization has emphasised healthy ageing and functional ability in older people as key themes of the current decade [1]. Healthy ageing is described as a process that develops, maintains, and promotes functional ability, which in turn enables wellbeing in advancing age [1]. Functional ability in this context refers to older people’s capabilities to do what they perceive as important in their lives, including being mobile and active in society, are supported by the environment, such as through health care and services [1]. However, some long-term health conditions, such as rheumatoid arthritis (RA), pose several health-related threats that negatively affect safe and active ageing [2]. RA is more likely to affect women and is common with increasing age [3]. The age-specific prevalence rate of RA peaks in the age group of 59–75 years [4]. Therefore, to support the mobility and independence of older age individuals, it is essential to determine how older people with RA perceive their lower extremity health. Lower extremity health in this study was defined as the structure and functions of the lower extremities from the hips to the toes.

Foot health in older people with RA is important to maintain and promote independent walking and functional ability. However, foot health problems are prevalent in RA [5, 6]. These problems are often due to polyarthritis, with joint stiffness and pain caused by inflammation in the joints of the foot. It is estimated that almost 90% of patients with RA suffer from foot problems [7] or foot dysfunction [8]. Older people with RA report having foot problems that limit their ability to perform daily activities [6, 9].

Lower extremity function is a precondition for safe ambulation. Lower extremity function, together with high physical activity and low levels of pain, is correlated with patients’ perception of good health [10]. However, due to the inflammatory nature of RA, joint stiffness and pain often result in impairments in the lower extremities. Limited joint mobility and decreased muscle strength may lead to disabilities, causing significant problems, particularly for those engaging in dynamic activities such as walking or stair climbing [10]. Limited lower extremity function has been reported to result in high levels of kinesiophobia [11, 12] and decreased quality of life [13].

Previous evidence of the association between self-assessed foot health and perceived lower extremity function in older people with RA is scarce. There is evidence that foot deformities have an impact on foot function [14, 15]. In particular, foot structural deformities such as hallux valgus and lesser toe deformities alter gait and foot function, which may lead to unsteady walking and balance [14]. Moreover, problems in the midfoot and hindfoot affect functional disability and walking [16]. However, studies on this topic were focused on conducting mainly clinically objective foot and lower extremity assessments rather than investigating the subjective perceptions of older people with RA.

Given the importance of foot health and lower extremity function among people with RA, the aim of this study was to analyse the level of foot health and lower extremity function in older people with RA and to investigate their associations. Following research questions were set:

  • 1.

    What is the average level of foot health in older people with RA?

  • 2.

    What is the average lower extremity function in older people with RA?

  • 3.

    What, if any, is the association between foot health and lower extremity function in older people with RA?

A cross-sectional survey design was applied. The data were collected through online survey distributed through a national patient association of rheumatic conditions in Finland to people with RA (N = 2,400). Webropol online survey tool was used to collect the data. The online survey was constructed to be as short as possible in order to minimise respondent burden and be simple in design to promote easy and quick administration [17]. The online survey was pilot-tested with 10 participants to ensure technical functionality and clarity of items and response instructions. After pilot-test only minor modifications to the layout of the survey was made.

All members of the national association who were adults (age 18 years and older), diagnosed with rheumatoid arthritis, had an email address in the member registry of the association and were voluntarily willing to participate in the study were invited. A contact person of the association distributed an invitation letter to all potential participants via email. The data were collected in April 2023. Two reminders to respond the survey were sent resulting to some increase in response rate. This study reported in this article is a part of a larger nationwide foot health in RA (n = 656) study. For the purposes of this article, a sub-data of older people (age 65 +) with RA (n = 270) were used as RA is relatively common in older people [4].

Instruments

Foot health levels were measured using the Self-administered Foot Health Assessment Instrument (S-FHAI) [18]. The S-FHAI is a subjective self-assessment measure of current foot health with 22 items. Four subcategories were included: skin health (12 items), nail health (4 items), foot structure (5 items), and foot pain (1 item). The response options are dichotomous (no-yes). By summing up the values, the S-FHAI produces a total foot health sum variable ranging from 22 to 44. The higher the values, the poorer the foot health. The S-FHAI has been used successfully in previous studies to collect data from nurses [18] and people with RA [6, 7] demonstrating satisfactory internal consistency (0.67, 0.72, respectively). Moreover, unidimensionality, with an acceptable item fit using Rasch analysis, has been reported acceptable in previous studies [19].

The Lower Extremity Function Scale (LEFS) [20] measures the functional impairment of a patient with a disorder of one or both lower extremities. It consists of 20 questions seeking to determine respondent’s ability to perform everyday tasks, such as walking inside and outside the home, taking care of one’s personal hygiene and engaging in recreational activities. The response scale is a five-point rating scale (0 = extreme difficulty or inability to perform activity, 4 = no difficulty performing the activity). The values of each item are summed together, leading to a total score that ranges between 0 and 80. The lower the score, the greater the disability. The scores of the LEFS were categorised, and functional limitation can be interpreted as follows: 0–20: severe; 21–40: moderate; 41–60: mild to moderate; 61–80: minimal (normal function) functional limitation [21]. The internal consistency (Cronbach’s alpha 0.96), test-retest reliability, sensitivity, and responsiveness of the LEFS has been demonstrated to be acceptable [20, 22, 23]. Previously, the LEFS has been used to measure functional decline caused by several lower extremity disorders such as osteoarthritis, knee, or ankle injuries [22]. Our background questions covered age, gender, duration of RA, highest education, perception of how much foot health affects performance in daily activities in general and self-evaluated level of foot health (0 = poorest foot health, 10 = excellent foot health).

Data Analysis

The data were analysed statistically using SPSS 22.0 software (SPSS Inc., Chicago, IL). Firstly, descriptive statistics (i.e., frequencies, percentages, means, and standard deviations) were calculated to describe foot health, lower extremity function and respondents’ background factors. Secondly, the sum variables of total foot health, skin health, nails, foot structure, foot pain, and lower extremity function were formulated by counting the item scores and dividing the sum by the number of items. Thirdly, the associations between foot health sum variables and lower extremity function sum variables were tested using the Pearson correlation coefficient. The statistical significance level was set to 0.05. The reliability of the S-FHAI and LEFS were analysed using Cronbach’s alpha coefficient.

Ethical Considerations

The study followed good scientific practice in each phase [24]. The ethical approval was obtained (code: 35/2021) from the University’s Ethical Committee and permission to collect the data according to standard procedures of the patient association. The participants received a cover letter together with a link to the survey distributed by the contact person of the national patient association. The cover letter included a description of data collection procedures, anonymity, confidentiality, the right to withdraw, and reporting. After reading the cover letter, the participants indicated their informed consent electronically and then proceeded to answer the survey questions.

Description of Participants

A total of 270 persons with RA participated in the study (Table 1). Their mean age was 71.2 (range: 65–87, SD: 4.8). The duration of RA was 17.7 years (range: 1–70, SD: 14.5). The majority of the participants were female (n = 225, 85%). The educational background of participants was commonly university of applied sciences (n = 95, 35%), elementary school (n = 63, 23%), or university (n = 52, 19%). Most of the participants perceived that their foot health affected their performance in daily activities very much (n = 105, 39%) or much (n = 106, 39%). Their self-assessed level of foot health was 6.5 on average (range: 1–10, SD: 1.7).

Table 1.

Participants’ (n = 270) background characteristics

Background variablef(%)Mean (SD)RangeMedian
Age   71.2 (4.8) 65–87 70 
Duration of RA   17.7 (14.5) 1–70 12.5 
Gender 
 Female 225 85    
 Male 39 15    
Highest education 
 University of applied sciences 95 36    
 Vocational school 63 24    
 University 52 20    
 Elementary school 48 18    
 High school    
Effect of foot health to daily activities 
 Very much 105 39    
 Much 108 40    
 Neither too much nor too little 37 19    
 Little 13    
 Very little    
Self-evaluated level of foot health   6.5 (1.7) 1–10 
Background variablef(%)Mean (SD)RangeMedian
Age   71.2 (4.8) 65–87 70 
Duration of RA   17.7 (14.5) 1–70 12.5 
Gender 
 Female 225 85    
 Male 39 15    
Highest education 
 University of applied sciences 95 36    
 Vocational school 63 24    
 University 52 20    
 Elementary school 48 18    
 High school    
Effect of foot health to daily activities 
 Very much 105 39    
 Much 108 40    
 Neither too much nor too little 37 19    
 Little 13    
 Very little    
Self-evaluated level of foot health   6.5 (1.7) 1–10 

Level of Foot Health in People with RA

Older people with RA reported experiencing many foot health problems (Table 2). The mean total foot health sum variable was 30 (range: 15–40, SD: 3.3), indicating a great number of foot problems and thus decreased foot health levels. High percentages of foot problem occurrence were identified on the subscale level. In the area of foot skin, the most common problems were dry skin (n = 195, 73%), oedema (n = 177, 66%), and corns or calluses (n = 161, 60%). Thickened toenails (n = 173, 64%) were the most prevalent toenail problem, followed by colour changes in the nails (n = 126, 47%). Overall, foot structural deformities were common, hammer toes (n = 150, 57%), hallux valgus (n = 137, 51%), and low foot arch (n = 116, 44%) being the most prevalent. A total of 206 of older people with RA (78%) experienced foot pain over the last 2 weeks prior to the survey.

Table 2.

Self-reported foot health in older people with RA (n = 270)

Variablef%
Foot skin 
 Skin breaks or maceration between toes 48 18 
 Dry skin 195 73 
 Fissures in the heel 93 34 
 Corns or calluses 161 60 
 Verrucae 27 10 
 Blisters 
 Oedema 177 66 
 Sweating feet 70 26 
 Burning feet 89 34 
 Cold feet 152 57 
 Leg cramps 157 59 
 Foot ulcers 
Toenails 
 Ingrown nail 42 16 
 Thickened nail 173 64 
 Colour changes in the nails 126 47 
 Fungal infection of the nails 26 10 
Foot structure 
 Hallux valgus 137 51 
 Taylor’s bunion 86 33 
 Hammer toe 150 57 
 Low foot arch 116 44 
 High foot arch 32 12 
Foot pain 206 78 
Variablef%
Foot skin 
 Skin breaks or maceration between toes 48 18 
 Dry skin 195 73 
 Fissures in the heel 93 34 
 Corns or calluses 161 60 
 Verrucae 27 10 
 Blisters 
 Oedema 177 66 
 Sweating feet 70 26 
 Burning feet 89 34 
 Cold feet 152 57 
 Leg cramps 157 59 
 Foot ulcers 
Toenails 
 Ingrown nail 42 16 
 Thickened nail 173 64 
 Colour changes in the nails 126 47 
 Fungal infection of the nails 26 10 
Foot structure 
 Hallux valgus 137 51 
 Taylor’s bunion 86 33 
 Hammer toe 150 57 
 Low foot arch 116 44 
 High foot arch 32 12 
Foot pain 206 78 

Self-administered Foot Health Assessment Instrument (S-FHAI, Stolt et al. 2017) © Stolt.

Lower Extremity Function in People with RA

Lower extremity function in older people with RA was on at a mild-to-moderate functional limitation level (mean: 54.5, SD: 16.3, range: 13–80, Table 3). Older people with RA reported extreme difficulties with or an inability to run, hop, squat, engage in their usual hobbies, perform strenuous activities outside the home or put on shoes and socks.

Table 3.

Participants’ (n = 270) self-reported lower extremity function

ActivitynExtreme difficult or unable to perform activityQuite a bit of difficultyModerate difficultyA little bit of difficultyNo difficulty
f (%)f (%)f (%)f (%)f (%)
Work, housework, or school activities 267 2 (1) 9 (3) 41 (15) 105 (39) 110 (41) 
Usual hobbies, recreational, or sporting activities 268 4 (2) 23 (9) 55 (20) 132 (49) 54 (20) 
Getting into or out of the bath 254 23 (9) 17 (6) 23 (9) 59 (22) 132 (49) 
Walking between the rooms 264 2 (1) 3 (1) 14 (5) 62 (24) 183 (69) 
Putting on shoes or socks 268 4 (2) 6 (2) 32 (12) 109 (41) 117 (44) 
Squatting 269 30 (11) 24 (9) 50 (19) 86 (32) 79 (29) 
Lifting an object 269 3 (1) 13 (5) 23 (9) 88 (33) 142 (53) 
Light activities 268 0 (0) 4 (2) 16 (6) 75 (28) 173 (64) 
Heavy activities 269 18 (7) 39 (15) 63 (23) 99 (37) 50 (19) 
Getting into or out of a car 269 4 (2) 14 (5) 24 (9) 116 (43) 111 (41) 
Walking 2 blocks 269 7 (3) 13 (5) 26 (10) 63 (23) 160 (60) 
Walking 1 km 269 16 (6) 19 (7) 33 (12) 72 (27) 129 (48) 
Going up or downs 10 stairs 268 10 (4) 29 (11) 46 (17) 72 (27) 111 (41) 
Standing for 1 h 269 30 (11) 43 (16) 51 (19) 75 (28) 70 (26) 
Sitting for 1 h 269 0 (0) 9 (3) 26 (10) 86 (32) 148 (55) 
Running on even ground 265 94 (36) 40 (15) 51 (19) 45 (17) 35 (13) 
Running on uneven ground 267 110 (41) 40 (15) 51 (19) 49 (18) 17 (6) 
Making sharp turns while running fast 265 100 (38) 41 (16) 44 (17) 52 (20) 28 (11) 
Hopping 264 101 (38) 40 (15) 54 (21) 48 (18) 21 (8) 
Rolling over in bed 267 2 (1) 13 (5) 31 (11) 94 (35) 127 (48) 
ActivitynExtreme difficult or unable to perform activityQuite a bit of difficultyModerate difficultyA little bit of difficultyNo difficulty
f (%)f (%)f (%)f (%)f (%)
Work, housework, or school activities 267 2 (1) 9 (3) 41 (15) 105 (39) 110 (41) 
Usual hobbies, recreational, or sporting activities 268 4 (2) 23 (9) 55 (20) 132 (49) 54 (20) 
Getting into or out of the bath 254 23 (9) 17 (6) 23 (9) 59 (22) 132 (49) 
Walking between the rooms 264 2 (1) 3 (1) 14 (5) 62 (24) 183 (69) 
Putting on shoes or socks 268 4 (2) 6 (2) 32 (12) 109 (41) 117 (44) 
Squatting 269 30 (11) 24 (9) 50 (19) 86 (32) 79 (29) 
Lifting an object 269 3 (1) 13 (5) 23 (9) 88 (33) 142 (53) 
Light activities 268 0 (0) 4 (2) 16 (6) 75 (28) 173 (64) 
Heavy activities 269 18 (7) 39 (15) 63 (23) 99 (37) 50 (19) 
Getting into or out of a car 269 4 (2) 14 (5) 24 (9) 116 (43) 111 (41) 
Walking 2 blocks 269 7 (3) 13 (5) 26 (10) 63 (23) 160 (60) 
Walking 1 km 269 16 (6) 19 (7) 33 (12) 72 (27) 129 (48) 
Going up or downs 10 stairs 268 10 (4) 29 (11) 46 (17) 72 (27) 111 (41) 
Standing for 1 h 269 30 (11) 43 (16) 51 (19) 75 (28) 70 (26) 
Sitting for 1 h 269 0 (0) 9 (3) 26 (10) 86 (32) 148 (55) 
Running on even ground 265 94 (36) 40 (15) 51 (19) 45 (17) 35 (13) 
Running on uneven ground 267 110 (41) 40 (15) 51 (19) 49 (18) 17 (6) 
Making sharp turns while running fast 265 100 (38) 41 (16) 44 (17) 52 (20) 28 (11) 
Hopping 264 101 (38) 40 (15) 54 (21) 48 (18) 21 (8) 
Rolling over in bed 267 2 (1) 13 (5) 31 (11) 94 (35) 127 (48) 

The Lower Extremity Function Scale (LEFS, Bingley et al. 1999) © Bingley.

Association between Foot Health and Lower Extremity Function in People with RA

The poor level of foot health correlated with poor lower extremity function (−0.255, p < 0.001). The same correlative association between foot health and lower extremity function was found on each foot health subscale: skin health (−0.191, p = 0.002), toenails (−0.132, p = 0.031), foot structure (−0.199, p = 0.001), and foot pain (−0.323, p < 0.001).

Foot health and lower extremity function in people with RA had a weak, but significant, association. This indicates that foot problems are correlated with functional disability. This study illuminates the lived experiences of people with RA in terms of their foot problems and lower extremity function. The results of this study support and build on previous knowledge that foot problems impact foot function [14, 15].

Older people with RA reported many foot problems associated with their lower extremity function. Foot problems are common in older people [25]. RA is a long-term health problem, and its inflammatory nature may produce further problems. The level of foot health in older people with RA in this study seems to be lower compared to older people studied in previous studies [26]. In particular, the incidence of foot pain was high and correlated to lower extremity function. Foot pain is a common symptom in RA and can be caused by changes in joints and ligaments or by altered foot function. The study’s results indicate the need for regular foot health assessments and individually tailored podiatric care. Nowadays, podiatric care for people with RA is organised in diverse ways despite the international care guidelines emphasising multidisciplinary care with access to adequate footcare [27]. In some countries, podiatry forms part of systematic multiprofessional care for people with RA [27]; in Finland, however, the country where the study was conducted, podiatric care for people with RA is fragmented and is not sufficiently part of routine RA care [28]. Therefore, it is essential that people with RA have access to podiatric care and their foot health is also assessed during routine consultations.

In addition to podiatric care, accurate lower extremity function assessment is central to providing an overall status of a patient’s functional health. Lower extremity function is important in daily activities. Along with advancing age, lower extremity function may decrease, often suddenly, if muscle strength and joint mobility are not maintained. Even slight changes in lower extremity function may have detrimental effects on individuals’ daily lives, resulting in poorer physical performance [29]. Such physical performance can, for example, increase the risk of falls [30]. Paying attention to foot health in older people with RA is extremely important, as poor lower extremity function may lead to inactivity and a sedentary lifestyle [31]. These may in turn produce secondary effects such as decreased muscle strength and increased risk of falls [32]. To mitigate these secondary effects, preventative care and rehabilitation interventions are needed.

As the onset of RA commonly occurs at older ages, it is essential to pay attention to foot health and lower extremity function in order to maintain and promote functional activity for those advancing in age. The results of this study underline the need for proactive multiprofessional rehabilitation when caring for older people with RA with compromised lower extremity functions.

The results provided here have implications for both clinical practice and for the design of future clinical studies in people with RA. In clinical practice, older people with RA could benefit from regular foot health assessments and podiatric care. The systematic assessment and follow-up of foot health could provide information on changes in foot health and thus the need for podiatric care. A thorough lower extremity biomechanical assessment could reveal the need for individualised foot orthoses that could improve foot function [33]. In addition, foot self-care information delivered through, for example, patient associations or digital platforms [34] could help older people with RA advance their skills and knowledge in terms of caring for their own feet. Multiprofessional collaboration is much needed for the promotion of lower extremity function, as various professionals, such as podiatrists, physiotherapists, occupational therapists, and physicians, could provide their combined expertise on treating older people with RA. Future clinical studies could focus on testing multiprofessional lower extremity health interventions in which evidence-based information is gathered for older people to maintain and promote their lower extremity health and in which clinical consultations to podiatry, physiotherapy and occupational therapy or medicine are provided. Overall, older people with RA need help and support with their foot health and lower extremity function. Therefore, it is essential to structure health care services to cover the multidimensional health needs of these individuals. Structuring the co-creation of services for other patients and public involvement methods [35] could boost the alignment of the services and allow them become even more patient-centred.

Limitations

This study has some limitations that limit the generalisability of the results. The data were collected using self-assessments – older people with RA provided information about their current foot health and lower extremity function. This subjective approach might have led to some variations in the results, as individuals commonly underestimate their health status in their subjective evaluations [36]. However, subjective perception of foot health and lower extremity function is important as they both may influence physical activity, particularly in people with long-term health conditions such as RA. The data were collected in electronic format in collaboration with a national patient association, which may have caused some selection bias as not all people with RA are members of the national patient association, and some may not use electronic devices to respond to surveys. The data in this study were collected using commonly used structured instruments with acceptable internal consistency reliability (Cronbach’s alpha coefficient: S-FHAI 0.60, LEFS 0.96) providing psychometric evidence of their use among a sample of people with RA.

This study demonstrated the existence of a weak but significant association between foot health and lower extremity function in older people with RA. The results indicate the need for systematic foot health assessment, care and rehabilitation for older people with RA. Multiprofessional collaboration could benefit the promotion of functional health in older people with RA. Future research could focus on testing multiprofessional rehabilitation interventions targeted toward improving older individuals’ confidence and management of foot problems. Moreover, offering foot health services with easy access to older people with RA is important for promoting their active ageing.

This study protocol was reviewed and approved by [University of Turku, the Health Care Division of the Ethics Committee for Human Sciences], approval number [35/2021]. Participants gave their written informed consent to participate the study.

The authors have no conflicts of interest to declare.

This study was supported by Turku University Hospital (special grant in aid VTR 13240).

Conception and design of the research: M.S. and R.S.; acquisition of data and writing of the manuscript: M.S.; analysis and interpretation of the data: J.K., N.N., and M.S.; statistical analysis: J.K.; and critical revision of the manuscript for intellectual content: N.N. and R.S. All authors read and approved the final draft.

The data that support the findings of this study are not publicly available due to confidentiality as it containing information that could compromise the privacy of research participants but are available from the corresponding author on reasonable request [M.S.].

1.
World Health Organization [Internet]
.
UN decade of healthy ageing: plan of action 2021-2030
. [cited 2024 Mar 14]. Available from: https://www.who.int/initiatives/decade-of-healthy-ageing (Accessed March 17, 2024).
2.
Kakagia
DD
,
Karadimas
EJ
,
Stouras
IA
,
Papanas
N
.
The ageing foot
.
Int J Low Extrem Wounds
.
2023
:
15347346231203279
.
3.
Slobodin
G
.
Rheumatoid arthritis
. In:
Slobodin
G
,
Shoenfeld
Y
, editors.
Rheumatic disease in geriatrics: diagnosis and management
.
Cham
:
Springer
;
2020
. p.
173
83
.
4.
GBD 2021 Rheumatoid Arthritis Collaborators
.
Global, regional, and national burden of rheumatoid arthritis, 1990-2020, and projections to 2050: a systematic analysis of the Global Burden of Disease Study 2021
.
Lancet Rheumatol
.
2023
;
5
(
10
):
e594
610
.
5.
Wilson
O
,
Hewlett
S
,
Woodburn
J
,
Pollock
J
,
Kirwan
J
.
Prevalence, impact and care of foot problems in people with rheumatoid arthritis: results from a United Kingdom based cross-sectional survey
.
J Foot Ankle Res
.
2017
;
10
:
46
.
6.
Stolt
M
,
Kilkki
M
,
Katajisto
J
,
Suhonen
R
.
Self-assessed foot health in older people with rheumatoid arthritis-A cross-sectional study
.
Int J Old People Nurs
.
2021
;
16
(
4
):
e12380
.
7.
Stolt
M
,
Laitinen
AM
,
Kankaanpää
K
,
Katajisto
J
,
Cherry
L
.
The prevalence of foot health problems in people living with a rheumatic condition: a cross-sectional observational epidemiological study
.
Rheumatol Int
.
2023
;
43
(
2
):
283
91
.
8.
de Andrade
AP
,
Inoue
EN
,
Nisihara
R
,
Skare
TL
.
Foot function in rheumatoid arthritis patients: a cross-sectional study
.
Clin Rheumatol
.
2018
;
37
(
12
):
3427
30
.
9.
Chapman
LS
,
Flurey
CA
,
Redmond
AC
,
Richards
P
,
Hofstetter
C
,
Tapster
B
, et al
.
Living with foot and ankle disorders in rheumatic and musculoskeletal diseases: a systematic review of qualitative studies to inform the work of the OMERACT Foot and Ankle Working Group
.
Semin Arthritis Rheum
.
2023
;
61
:
152212
.
10.
Mellblom Bengtsson
M
,
Hagel
S
,
Jacobsson
L
,
Turesson
C
.
Lower extremity function in patients with early rheumatoid arthritis during the first five years, and relation to other disease parameters
.
Scand J Rheumatol
.
2019
;
48
(
5
):
367
74
.
11.
Yildiz
S
,
Kirdi
E
,
Bek
N
.
Comparison of the lower extremity function of patients with foot problems according to the level of kinesiophobia
.
Somatosens Mot Res
.
2020
;
37
(
4
):
284
7
.
12.
Reinoso-Cobo
A
,
Ortega-Avila
AB
,
Ramos-Petersen
L
,
García-Campos
J
,
Banwell
G
,
Gijon-Nogueron
G
, et al
.
Relationship between kinesiophobia, foot pain and foot function, and disease activity in patients with rheumatoid arthritis: a cross-sectional study
.
Med Kaunas
.
2023
;
59
(
1
):
147
.
13.
Nagafusa
T
,
Mizushima
T
,
Suzuki
M
,
Yamauchi
K
.
Comprehensive relationship between disease activity indices, mTSS, and mHAQ and physical function evaluation and QOL in females with rheumatoid arthritis
.
Sci Rep
.
2023
;
13
(
1
):
21905
.
14.
Fazaa
A
,
Triki
W
,
Ouenniche
K
,
Sellami
M
,
Miladi
S
,
Souabni
L
, et al
.
Assessment of the functional impact of foot involvement in patients with rheumatoid arthritis
.
Foot
.
2022
;
52
:
101907
.
15.
Erdem
IH
,
Kanar
M
.
Foot deformities in rheumatoid arthritis patients and their effects on foot functions
.
Eur Rev Med Pharmacol Sci
.
2023
;
27
(
5
):
1844
51
.
16.
Jeong
HJ
,
Sohn
IW
,
Kim
D
,
Cho
SK
,
Park
SB
,
Sung
IH
, et al
.
Impact of midfoot and Hindfoot involvement on functional disability in Korean patients with rheumatoid arthritis
.
BMC Musculoskelet Disord
.
2017
;
18
(
1
):
365
.
17.
Sammut
R
,
Griscti
O
,
Norman
IJ
.
Strategies to improve response rates to web surveys: a literature review
.
Int J Nurs Stud
.
2021
;
123
:
104058
.
18.
Stolt
M
,
Suhonen
R
,
Kielo
E
,
Katajisto
J
,
Leino-Kilpi
H
.
Foot health of nurses-A cross-sectional study
.
Int J Nurs Pract
.
2017
;
23
(
4
)
19.
Stolt
M
,
Kottorp
A
,
Suhonen
R
.
A Rasch analysis of the self-administered foot health assessment instrument (S-fhai)
.
BMC Nurs
.
2021
;
20
(
1
):
98
.
20.
Binkley
JM
,
Stratford
PW
,
Lott
SA
,
Riddle
DL
.
The lower extremity functional scale (LEFS): scale development, measurement properties, and clinical application. North American orthopaedic rehabilitation research network
.
Phys Ther
.
1999
;
79
(
4
):
371
83
.
21.
MAT assessment [Internet]
.
Lower extremity functional scale
. [cited 2024 Mar 5]. Available from: https://www.matassessment.com/blog/lower-extremity-functional-scale
22.
Mehta
SP
,
Fulton
A
,
Quach
C
,
Thistle
M
,
Toledo
C
,
Evans
NA
.
Measurement properties of the lower extremity functional scale: a systematic review
.
J Orthop Sports Phys Ther
.
2016
;
46
(
3
):
200
16
.
23.
Beauchamp
M
,
Hao
Q
,
Kuspinar
A
,
Alder
G
,
Makino
K
,
Nouredanesh
M
, et al
.
Measures of perceived mobility ability in community-dwelling older adults: a systematic review of psychometric properties
.
Age Ageing
.
2023
;
52
(
Suppl 4
):
iv100
11
.
24.
ALLEA [Internet]
.
The European code of conduct for research integrity
. [cited 2024 Mar 3]. Available from: https://allea.org/portfolio-item/european-code-of-conduct-2023/
25.
Oh-Park
M
,
Kirschner
J
,
Abdelshahed
D
,
Kim
DDJ
.
Painful foot disorders in the geriatric population: a narrative review
.
Am J Phys Med Rehabil
.
2019
;
98
(
9
):
811
9
.
26.
Stolt
M
,
Suhonen
R
,
Puukka
P
,
Viitanen
M
,
Voutilainen
P
,
Leino-Kilpi
H
.
Foot health and self-care activities of older people in home care
.
J Clin Nurs
.
2012
;
21
(
21–22
):
3082
95
.
27.
Tenten-Diepenmaat
M
,
van der Leeden
M
,
Vliet Vlieland
TPM
,
Dekker
J
;
RA Foot Expert Group
.
Multidisciplinary recommendations for diagnosis and treatment of foot problems in people with rheumatoid arthritis
.
J Foot Ankle Res
.
2018
;
11
:
37
.
28.
Rheumatoid Arthritis. Current Care Guidelines
[Internet] working group set up the Finnish medical society duodecim and the Finnish society for rheumatology
.
Helsinki
:
The Finnish Medical Society Duodecim
;
2022
. [cited 2024 Mar 16]. Available from: www.kaypahoito.fi
29.
Siltanen
S
,
Portegijs
E
,
Saajanaho
M
,
Poranen-Clark
T
,
Viljanen
A
,
Rantakokko
M
, et al
.
The combined effect of lower extremity function and cognitive performance on perceived walking ability among older people: a 2-year follow-up study
.
J Gerontol A Biol Sci Med Sci
.
2018
;
73
(
11
):
1568
73
.
30.
Duan
H
,
Wang
H
,
Bai
Y
,
Lu
Y
,
Xu
X
,
Wu
J
, et al
.
Health-related physical fitness as a risk factor for falls in elderly people living in the community: a prospective study in China
.
Front Public Health
.
2022
;
10
:
874993
.
31.
Wu
YZ
,
Loh
CH
,
Hsieh
JG
,
Lin
SZ
.
Physical inactivity and possible sarcopenia in rural community daycare stations of taiwan: a cross-sectional study
.
Int J Environ Res Public Health
.
2022
;
19
(
4
):
2182
.
32.
Pol
F
,
Khajooei
Z
,
Hosseini
SM
,
Taheri
A
,
Forghany
S
,
Menz
HB
.
Foot and ankle characteristics associated with fear of falling and mobility in community-dwelling older people: a cross-sectional study
.
J Foot Ankle Res
.
2022
;
15
(
1
):
86
.
33.
Tenten-Diepenmaat
M
,
Dekker
J
,
Twisk
JWR
,
Huijbrechts
E
,
Roorda
LD
,
van der Leeden
M
.
Outcomes and potential mechanism of a protocol to optimize foot orthoses in patients with rheumatoid arthritis
.
BMC Musculoskelet Disord
.
2020
;
21
(
1
):
348
.
34.
Palmer
JL
,
Siddle
HJ
,
Redmond
AC
,
Alcacer-Pitarch
B
.
Implementation of podiatry telephone appointments for people with rheumatic and musculoskeletal diseases
.
J Foot Ankle Res
.
2021
;
14
(
1
):
4
.
35.
Greenhalgh
T
,
Hinton
L
,
Finlay
T
,
Macfarlane
A
,
Fahy
N
,
Clyde
B
, et al
.
Frameworks for supporting patient and public involvement in research: systematic review and co-design pilot
.
Health Expect
.
2019
;
22
(
4
):
785
801
.
36.
Althubaiti
A
.
Information bias in health research: definition, pitfalls, and adjustment methods
.
J Multidiscip Healthc
.
2016
;
9
:
211
7
.