Three-dimensional kinematics at the ankle joint complex in rheumatoid arthritis patients with painful valgus deformity of the rearfoot

Time-of-day effects on the postural control and symptoms in women with rheumatoid arthritis

The present study was designed to assess time-of-day effects on postural balance and symptoms of rheumatoid arthritis (RA) patients. A total of 15 American College of Rheumatology functional class I and II RA patients and 15 healthy controls aged between 45 and 55 (mean age: 50 ± 3) years of age voluntarily participated. We conducted a case-control, repeated-measures in design study. Postural balance, axillary temperature, pain intensity, fatigue, and sleepiness were measured during five test sessions at 06:00, 10:00, 14:00, 18:00, and 22:00 h. Participants were randomized to the order of test sessions, and each session was separated by >36 hours to minimize/eliminate learning effects. Center of pressure area (CoP_area) (p < .001), pain (p < .01), and sleepiness (p < .05) values were significantly higher at 06:00 and 22:00 h compared to 10:00, 14:00, and 18:00 h in the RA group. Fatigue significantly increased (p < .05) at 22:00 h in comparison to 10:00, 14:00, and 18:00 h in the RA group. Axillary temperature was significantly (p < .001) lower at 06:00 and at 22:00 h compared to 10:00, 14:00, and 18:00 h in the RA group. In the control group, there were no significant time-of-day difference in fatigue, but axillary temperature was significantly lower (p < .01) at 06:00 h compared to 10:00 h, 14:00, 18:00, and 22:00 h, sleepiness values were significantly higher (p < .05) at 06:00 and 22:00 h compared to 10:00, 14:00, and 18:00 h, and revealed CoP_area values were significantly (p < .05) higher at 06:00 h compared to 14:00 h. Finally, in the RA group, significant correlations were found between values of CoP_area and pain (r = 0.47; p < .001), sleepiness (r = 0.39; p < .01), fatigue (r = -0.46; p < .001), and also axillary temperature (r = -0.35; p < .001). Multiple linear regression analysis further indicated that in the RA group, time-of-day variation in postural balance was predicted collectively by that in pain and fatigue (30.7%) (R2 = 0.307; F = 11.53; p < .001). Our results first suggest that time-of-day significantly affects postural balance, axillary temperature, pain intensity, fatigue, and sleepiness in RA patients and second that the temporal variation observed in pain, fatigue, and somnolence are concomitant with that observed in postural balance.Abbreviations: RA: Rheumatoid arthritis; H&O questionnaire: Horne and Ostberg questionnaire; PSQI: Pittsburgh sleep quality index; HAQ: Health assessment questionnaire; SF-36: the short form-36; WOMAC: Western Ontario and McMaster Universities Osteoarthritis Index; CoP: The Center of foot Pressure; CoP_area: The Center of foot Pressure area; VAS: The Visual Analogue Scale; KSS: Karolinska Sleepiness Scale.

Effects of smart phone use on lower limb joint angle and dynamic balance during gait

BACKGROUND

Cognitive tasks influence gait by reducing balancing abilities. Diverse studies to date have examined dual-tasking and gait.

OBJECTIVE

This study aimed to determine the influences of smart phone use while walking on lower limb joint angle and dynamic balancing ability.

METHODS

Thirty healthy subjects were voluntarily recruited from the university population. All subjects were required to perform the tasks under three conditions: not using a smart phone, having a conversation by phone, and playing a smart phone game. Lower limb joint angle and dynamic balance ability related to smart phone use during gait were measured. Motion analysis was used to measure lower limb joint angle changes during gait, while balance measuring equipment was used to measure the dynamic balancing ability.

RESULTS

In the stability limit test to measure the changes in dynamic balancing abilities, significant differences were found among the different smart phone use conditions.

CONCLUSIONS

Smart phone use during movements that are required for balance requires special attention, and this study provides important basic data for follow-up studies.

Accurately Determining Proper Shoe Size in Patients With Rheumatoid Arthritis

PURPOSE

The aim of this descriptive study was to determine whether people with rheumatoid arthritis (RA) wear adequately fitting footwear.

DESIGN

This observational study was carried out in a health center between January and December 2014 in the state of A Coruña, Spain.

METHOD

A total of 166 patients (47 men, 119 women) completed all stages of the research process. A validated Brannock Device was used to record foot and shoe length and width.

FINDINGS

Only 64 (38.55%) participants wore shoes that met the needs and requirements of their feet, and 98 (59.03%) participants wore the incorrect shoe size, at least in one foot.

CONCLUSIONS

Many patients with RA often wear shoes that are too narrow for their foot. Assessing the proper footwear fit is an important part of the clinical foot examination.

CLINICAL RELEVANCE

Early detection of inappropriate shoe size in patients with RA allows rehabilitation nurses to optimize foot health.

A protocol for a randomised controlled trial of prefabricated versus customised foot orthoses for people with rheumatoid arthritis: the FOCOS RA trial [Foot Orthoses - Customised v Off-the-Shelf in Rheumatoid Arthritis]

BACKGROUND

Foot pain is common in rheumatoid arthritis and appears to persist despite modern day medical management. Several clinical practice guidelines currently recommend the use of foot orthoses for the treatment of foot pain in people with rheumatoid arthritis. However, an evidence gap currently exists concerning the comparative clinical- and cost-effectiveness of prefabricated and customised foot orthoses in people with early rheumatoid arthritis. Early intervention with orthotics may offer the best opportunity for positive therapeutic outcomes. The primary aim of this study is to evaluate the comparative clinical- and cost-effectiveness of prefabricated versus customised orthoses for reducing foot pain over 12 months.

METHODS/DESIGN

This is a multi-centre two-arm parallel randomised controlled trial comparing prefabricated versus customised orthoses in participants with early rheumatoid arthritis (< 2 years disease duration). A total of 160 (a minimum of 80 randomised to each arm) eligible participants will be recruited from United Kingdom National Health Service Rheumatology Outpatient Clinics. The primary outcome will be foot pain measured via the Foot Function Index pain subscale at 12 months. Secondary outcomes will include foot related impairments and disability via the Foot Impact Scale for rheumatoid arthritis, global functional status via the Stanford Health Assessment Questionnaire, foot disease activity via the Rheumatoid Arthritis Foot Disease Activity Index, and health-related quality of life at baseline, 6 and 12 months. Process outcomes will include recruitment/retention rates, data completion rates, intervention adherence rates, and participant intervention and trial participation satisfaction. Cost-utility and cost-effectiveness analyses will be undertaken.

DISCUSSION

Outcome measures collected at baseline, 6 and 12 months will be used to evaluate the comparative clinical- and cost- effectiveness of customised versus prefabricated orthoses for this treatment of early rheumatoid arthritis foot conditions. This trial will help to guide orthotic prescription recommendations for the management of foot pain for people with early rheumatoid arthritis in future.

TRIAL REGISTRATION

ISRCTN13654421. Registered 09 February 2016.

Hip kinematics during functional tasks in females with patellofemoral pain: Modification following rehabilitation and correlation with clinical improvement

OBJECTIVES

To compare hip kinematics during two functional tasks in females with and without patellofemoral pain (PFP), and to determine if hip kinematics and, symptoms and functional limitations were improved after a rehabilitation program.

DESIGN

Cross sectional and longitudinal.

PARTICIPANTS

Sixteen females with and 15 without PFP.

SETTING

Laboratory and physical therapy clinic.

MAIN OUTCOME MEASURES

Hip adduction (HADD) and medial rotation (HMR) peak angles, time integrals and inter-movement variability during step-down and vertical drop jump, symptoms and functional limitations evaluated using the Activities of Daily Living Scale of the Knee Outcome Survey (KOS-ADLS).

RESULTS

At baseline, no significant differences were found in step-down and vertical drop jump between PFP and controls. Following rehabilitation, significant improvements were reported in KOS-ADLS (p < 0.001). There was a significant decrease in HADD and HMR variability (p < 0.05), a trend for decreased peak HMR (p = 0.06) during step-down, and a significant decrease in HADD variability (p < 0.05) during vertical drop jump. These kinematic changes did not correlate with changes in KOS-ADLS (all p > 0.05).

CONCLUSION

Females with and without PFP demonstrated no hip kinematic differences during functional tasks. A rehabilitation program improved symptoms and functional status, and modified hip kinematics in females with PFP; however these changes were not correlated.

A survey of people with foot problems related to rheumatoid arthritis and their educational needs

Background

Up to 50% of people with rheumatoid arthritis (RA) have foot symptoms at diagnosis, hence early foot health intervention is recommended and this should include patient education. This study identifies, for the first time, the foot health education (FHE) needs of people with RA.

Methods

An online survey of people with RA (n = 543) captured quantitative data in relation to the aims, methods of delivery, content, timing and accessibility of FHE.

Results

The majority concurred about the aims of FHE. Verbal delivery and websites were the most common methods. Written and verbal FHE were perceived to be the most effective methods. The point of diagnosis was the preferred time to receive it. Lack of access to FHE included minimal focus on foot health during consultations by both health practitioners and patients with RA. Participant gender, age, disease duration and living situation had a statistically significant influence on the results.

Conclusion

Foot health education is rarely considered within the medical consultation. There is a lack of patient and/or health professional awareness of this need with a detrimental impact on foot health. Patients require health professionals to identify their foot education health needs. Tailored foot health education should begin at initial diagnosis.

Electronic supplementary material

The online version of this article (doi:10.1186/s13047-017-0193-6) contains supplementary material, which is available to authorized users.

Foot Health Education for People with Rheumatoid Arthritis: '…. A Game of Chance…' - A Survey of Patients' Experiences

OBJECTIVE

Up to 90% of people with rheumatoid arthritis (RA) experience foot problems leading to reduced function, mobility, quality of life and social participation, and impacts on body image, but these can be improved with general foot care, orthoses, footwear and patient education. Foot health patient education is lacking, so the aim of the present study was to identify the foot health educational needs of people with RA in relation to its content, timing, mode of delivery and the perceived barriers to its provision.

METHODS

People with RA completed an online survey and provided free-text comments for thematic analysis.

RESULTS

A total of 249 people completed the free-text section of the survey. Five main themes emerged: 'Forgotten feet'; 'Too little, too late'; 'Lacks and gaps'; 'I am my feet' and 'Game of chance'.

CONCLUSION

Foot pathology in people with RA has a bio-psychosocial impact on their lives. Foot health and related information appears to be considered rarely within the medical consultation. Access to foot health information and services is limited owing to a lack of patient and/or health professional awareness, with a detrimental impact on the prognosis of their foot health. The importance of foot health in people with RA should be reinforced for patients and health professionals alike. Opportunities to discuss foot health within the medical consultation should be provided regularly. Copyright © 2015 John Wiley & Sons, Ltd.

Gait characteristics associated with the foot and ankle in inflammatory arthritis: a systematic review and meta-analysis

BACKGROUND

Gait analysis is increasingly being used to characterise dysfunction of the lower limb and foot in people with inflammatory arthritis (IA). The aim of the systematic review was to evaluate the spatiotemporal, foot and ankle kinematic, kinetic, peak plantar pressure and muscle activity parameters between patients with inflammatory arthritis and healthy controls.

METHODS

An electronic literature search was performed on Medline, CINAHL, SportsDiscus and The Cochrane Library. Methodological quality was assessed using a modified Quality Index. Effect sizes with 95% confidence intervals (CI) were calculated as the standardised mean difference (SMD). Meta-analysis was conducted if studies were homogenous.

RESULTS

Thirty six studies with quality ranging from high to low met the inclusion criteria. The majority of studies reported gait parameters in Rheumatoid arthritis (RA). The gait pattern in RA was characterised by decreased walking speed (SMD 95% CI -1.57, -2.25 to -0.89), decreased cadence (SMD -0.97, -1.49 to -0.45), decreased stride length (SMD -1.66, -1.84 to -1.49), decreased ankle power (SMD -1.36, -1.70 to -1.02), increased double limb support time (SMD 1.03, 0.84 to 1.22), and peak plantar pressures at the forefoot (SMD 1.11, 0.76 to 1.45). Walking velocity was reduced in psoriatic arthritis and gout with no differences in ankylosing spondylitis. No studies have been conducted in polymyalgia rheumatica, systemic sclerosis or systemic lupus erythematosus.

CONCLUSIONS

The review identified the majority of studies reporting gait adaptations in RA, but limited evidence relating to other IA conditions. Poor data reporting, small sample sizes and heterogeneity across IA conditions limit the interpretation of the findings. Future studies may consider a standardised analytical approach to gait analysis that will provide clinicians and researchers with objective evidence of foot function in people with IA.

Effect of rocker shoes on pain, disability and activity limitation in patients with rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis is a chronic inflammatory joint disease which affects the joints and soft tissues of the foot and ankle. Rocker shoes may be prescribed for the symptomatic foot in rheumatoid arthritis; however, there is a limited evidence base to support the use of rocker shoes in these patients.

OBJECTIVES

The aim of this study was to evaluate the effectiveness of heel-to-toe rocker shoes on pain, disability, and activity limitation in patients with rheumatoid arthritis.

STUDY DESIGN

Clinical trial.

METHODS

Seventeen female patients with rheumatoid arthritis of 1 year or more duration, disease activity score of less than 2.6, and foot and ankle pain were recruited. Heel-to-toe rocker shoe was made according to each patient's foot size. All the patients were evaluated immediately, 7 and 30 days after their first visit. Foot Function Index values were recorded at each appointment.

RESULTS

With the use of rocker shoes, Foot Function Index values decreased in all subscales. This reduction was noted in the first visit and was maintained throughout the trials.

CONCLUSION

Rocker shoe can improve pain, disability, and activity limitation in patients with rheumatoid foot pain. All the subjects reported improved comfort levels.

CLINICAL RELEVANCE

The results of this study showed that high-top, heel-to-toe rocker shoe with wide toe box was effective at reducing foot and ankle pain. It was also regarded as comfortable and acceptable footwear by the patients with rheumatoid foot problems.

The effect of stroke on foot kinematics and the functional consequences

BACKGROUND

Although approximately one-third of stroke survivors suffer abnormal foot posture and this can influence mobility, there is very little objective information regarding the foot and ankle after stroke.

OBJECTIVE

As part of a programme of research examining foot and ankle biomechanics after stroke, we investigated multi-planar kinematics and the relationship with function.

METHODS

In a single assessment session, static foot posture (Foot Posture Index); mobility limitations (Walking Handicap Scale) and multi-segment foot and ankle kinematics during stance phase of walking were measured in 20 mobile chronic stroke survivors and 15 sex and age-matched healthy volunteers.

RESULTS

Compared to the healthy volunteers, the stroke survivors demonstrated consistently reduced range of motion across most segments and planes, increased pronation and reduced supination, disruption of the rocker and the timing of joint motion. Changes in pronation/supination were associated with limited walking ability.

CONCLUSIONS

This study provides evidence of structural and movement deficiencies in the intrinsic foot segments affected by stroke. These would not have been detectable using a single segment foot model. Data do not support common clinical practices that focus on correction of sagittal ankle deformity and assumed excessive foot supination. Some of these abnormalities were associated with limitation in functional ability. Biomechanical abnormalities of foot and ankle are modifiable and there is potential for clinical studies and future developments of interventions to help prevent or treat these abnormalities which may improve functional ability post stroke.

Biomechanics of the natural, arthritic, and replaced human ankle joint

The human ankle joint complex plays a fundamental role in gait and other activities of daily living. At the same time, it is a very complicated anatomical system but the large literature of experimental and modelling studies has not fully described the coupled joint motion, position and orientation of the joint axis of rotation, stress and strain in the ligaments and their role in guiding and stabilizing joint motion, conformity and congruence of the articular surfaces, patterns of contact at the articular surfaces, patterns of rolling and sliding at the joint surfaces, and muscle lever arm lengths.

The present review article addresses these issues as described in the literature, reporting the most recent relevant findings.

Tibialis posterior tenosynovitis and associated pes plano valgus in rheumatoid arthritis: electromyography, multisegment foot kinematics, and ultrasound features

Objective

To compare electromyographic (EMG), kinematic, kinetic, and ultrasound (US) features of pes plano valgus associated with US-confirmed tibialis posterior (TP) tenosynovitis in rheumatoid arthritis (RA) and healthy control subjects.

Methods

In this cross-sectional study, patients with RA and US-confirmed tenosynovitis of TP underwent gait analysis, including 3-dimensional kinematics, kinetics, and intramuscular EMG of TP, and findings were compared with a group of healthy individuals. The RA group also underwent B mode and power Doppler US scanning of the TP tendon to assess and score levels of pathology.

Results

Ten patients with RA, median (range) disease duration of 3 years (1–18 years), and 5 control subjects were recruited. Compared to control subjects, the RA patients walked slower and presented with moderate levels of foot-related disability. The mean ± SD Disease Activity Score in 28 joints was 4.6 ± 1.6. Increased magnitude of TP activity was recorded in the RA group compared to controls in the contact period of stance (P = 0.007), in conjunction with reduced ankle joint power (P = 0.005), reduced navicular height in the medial arch (P = 0.023), and increased forefoot dorsiflexion (P = 0.027). TP tendon thickening, fluid, and power Doppler signal were observed in the majority of patients.

Conclusion

This study has demonstrated, for the first time, increased TP EMG activity in the presence of US-confirmed TP tenosynovitis in RA. Altered muscle function occurred in conjunction with suboptimal mechanics, moderate levels of tendon pathology, and active disease. Targeted therapy may be warranted to reduce inflammation and mechanically off-load diseased tendon states.

Dose-response effects of customised foot orthoses on lower limb kinematics and kinetics in pronated foot type

Despite the widespread use of customised foot orthoses (FOs) for the pronated foot type there is a lack of reliable information on the dose-response effect on lower limb mechanics. This study investigated these effects in subjects with normal and pronated foot types. Customised FOs were administered to 12 participants with symptomatic pronated foot type and 12 age and gender matched controls. A computer-aided design (CAD) software was used to design nine FOs per participant with dose incrementally changed by varying only the rearfoot post angle. This was done in 2° increments from 6° lateral to 10° medial posting. A 3D printing method was used to manufacture the FOs. Quantification of the dose-response effect was performed using three-dimensional gait analyses for selected rearfoot and knee kinematics and kinetics. Under these experimental conditions, significant and linear effects of posting were seen for the peak (p<0.001) and mean (p<0.001) rearfoot eversions, peak (p=0.003) and mean (p<0.001) ankle eversion moments and peak (p=0.017) and mean (p=0.005) knee adduction moment variables. Group effects were observed for the peak (p=0.007) and mean (p=0.007) forefoot abduction and for the peak (p=0.007) knee adduction moment. A significant interaction between posting and group was seen for internal tibial rotation (p=0.004). These data indicate that a dose-response effect, with a linear trend for both the rearfoot and knee, exists for customised FOs used to treat pronated foot type.

Gait deviations in individuals with inflammatory joint diseases and osteoarthritis and the usage of three-dimensional gait analysis

This chapter describes three-dimensional gait analysis and common gait deviations in adults with rheumatoid arthritis (RA) and osteoarthritis (OA). Furthermore, we describe changes in gait deviations following surgical and non-surgical interventions. Gait analysis is used to define gait deviations and to evaluate varying surgical approaches, types of surgeries and non-pharmacologic interventions. Most studies examine gait in adults with knee OA. Limitations of existing studies include small samples, poor selection of controls, sample heterogenecity, lack of baseline gait assessments and inconsistency in measurement. Across studies, time and distance parameters are generally used to provide a global measure of gait deviations. Individuals with RA and OA in the lower extremities exhibit reduced walking speed/cadence and decreased motion and moments in relation to healthy subjects. Future research should include larger sample sizes, the use of proper controls, pre- and post-assessments and identify gait abnormalities early in the disease process to minimise long-term consequences.

'My feet: visible, but ignored . . .' A qualitative study of foot care for people with rheumatoid arthritis

OBJECTIVE

To explore patients' experiences of foot problems associated with rheumatoid arthritis, from onset of symptoms to being provided with foot health interventions.

DESIGN

A qualitative design was used with an interpretive phenomenological approach to the data collection and analysis.

SETTING

University of Salford, School of Health Science.

SUBJECTS

Sixteen female and six male adults with rheumatoid arthritis-related foot problems and experience of receiving foot health interventions.

METHOD

Data were collected through digital recordings of three focus groups which were conducted by an experienced researcher. An observer made field notes. Transcribed data were analysed using a thematic framework. Data were verified with randomly selected participants and agreement achieved with the participants, researcher and observer.

RESULTS

The results were organized into five themes: the significance of foot symptoms in relation to diagnosis of rheumatoid arthritis; knowledge of and explanation about foot symptoms; accessing foot health interventions; the effectiveness of foot health interventions; and improvements to foot health interventions. Despite foot problems being of concern to the participants, they were often ignored by practitioners from before diagnosis through to foot management.

CONCLUSIONS

This study has highlighted a polarity between what these participants need in relation to their foot symptoms and the management of them. That foot problems are often ignored is of concern at multiple levels. These range from the implications of ignoring foot symptoms that may aid diagnosis of rheumatoid arthritis, to ignoring the need for effective foot health interventions.

Guidelines for the management of the foot health problems associated with rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) as a chronic systemic disease, commonly affects the feet, impacting negatively on patients' quality of life. Specialist podiatrists have a prime role to play in the assessment and management of foot and ankle problems within this patient group. However, it has been identified that in many areas there is no specialist podiatry service, with many patients being managed by non-specialist podiatrists. Therefore, the North West Clinical Effectiveness Group for the Foot in Rheumatic Diseases (NWCEG) identified the need to develop 'practitioner facing' guidelines for the management of specific foot health problems associated with RA.

METHODS

Members of a guideline development group from the NWCEG each reviewed the evidence for specific aspects of the assessment and management of foot problems. Where evidence was lacking, 'expert opinion' was obtained from the members of the NWCEG and added as a consensus on current and best practice. An iterative approach was employed, with the results being reviewed and revised by all members of the group and external reviewers before the final guideline document was produced.

RESULTS

The management of specific foot problems (callus, nail pathology, ulceration) and the use of specific interventions (foot orthoses, footwear, patient education, steroid injection therapy) are detailed and standards in relation to each are provided. A diagrammatic screening pathway is presented, with the aim of guiding non-specialist podiatrists through the complexity of assessing and managing those patients with problems requiring input from a specialist podiatrist and other members of the rheumatology multidisciplinary team.

CONCLUSION

This pragmatic approach ensured that the guidelines were relevant and applicable to current practice as 'best practice', based on the available evidence from the literature and consensus expert opinion. These guidelines provide both specialist and non-specialist podiatrists with the essential and 'gold standard' aspects of managing people with RA-related foot problems.

The use of gait analysis in the treatment of pediatric foot and ankle disorders

Assessment of foot pathology during walking should form an integral part of the clinical evaluation of children. Simple observation and video recording have limitations and are not quantifiable. Three-dimensional analysis of foot motion during walking can provide invaluable information on the dynamic function of the foot and can contribute to clinical decision making. As motion analysis technology advances, the accuracy and reliability of the dynamic assessment of the foot during walking will increase further, allowing clinicians to rely confidently on this information during patient assessment and the study of treatment outcomes. It is logical to expect that objective and quantifiable assessment of gait should be undertaken before and after treatment that sets gait improvement as one of its aims.

Looking through the 'window of opportunity': is there a new paradigm of podiatry care on the horizon in early rheumatoid arthritis?

Over the past decade there have been significant advances in the clinical understanding and care of rheumatoid arthritis (RA). Major paradigm changes include earlier disease detection and introduction of therapy, and 'tight control' of follow-up driven by regular measurement of disease activity parameters. The advent of tumour necrosis factor (TNF) inhibitors and other biologic therapies have further revolutionised care. Low disease state and remission with prevention of joint damage and irreversible disability are achievable therapeutic goals. Consequently new opportunities exist for all health professionals to contribute towards these advances. For podiatrists relevant issues range from greater awareness of current concepts including early referral guidelines through to the application of specialist skills to manage localised, residual disease activity and associated functional impairments. Here we describe a new paradigm of podiatry care in early RA. This is driven by current evidence that indicates that even in low disease activity states destruction of foot joints may be progressive and associated with accumulating disability. The paradigm parallels the medical model comprising early detection, targeted therapy, a new concept of tight control of foot arthritis, and disease monitoring.

'Podiatrists are experts on foot disorders: both patients and rheumatologists can profit from the involvement of a podiatrist'

- Korda and Balint, 2004 [1].

Foot structure and function in older people with radiographic osteoarthritis of the medial midfoot

OBJECTIVE

To investigate whether foot structure and dynamic foot function differ between older people with and without radiographically confirmed osteoarthritis (OA) of the talo-navicular joint (TNJ) and navicular-first cuneiform joint (N1(st)CJ).

METHOD

Dorso-plantar and lateral weighbearing foot radiographs (right feet) were obtained from 205 older people aged 61-94 years, and the presence of OA in the TNJ and N1(st)CJ was determined using a standardized atlas. Foot structure was assessed using a clinical measure (the arch index [AI]) and two radiographic measures (calcaneal inclination angle [CIA] and calcaneal-first metatarsal angle [C1MA]). Dynamic plantar pressure assessment during walking was undertaken using the Tekscan MatScan system.

RESULTS

Thirty-five participants exhibited radiographic OA in the TNJ and N1(st)CJ. There were no significant differences between the groups in relation to age, sex, weight or walking velocity. Compared to those without OA in these joints, those with OA had significantly flatter feet, as evidenced by larger AI (0.26+/-0.05 vs 0.25+/-0.05, P=0.02), smaller CIA (18.5+/-6.3 vs 21.3+/-5.4 degrees, P<0.01) and larger C1MA (137.0+/-9.3 vs 132.4+/-8.0 degrees, P<0.01), and exhibited significantly higher maximum forces in the midfoot (15.2+/-7.3 vs 11.2+/-7.0 kg, P<0.01; 36% increase).

CONCLUSION

Older people with radiographic OA of the TNJ and N1(st)CJ exhibit flatter feet and increased loading of the plantar midfoot when walking. Excessive loading of the midfoot may predispose to OA by increasing dorsal compressive forces, although prospective studies are required to confirm whether this relationship is causal.

Tibialis posterior in health and disease: a review of structure and function with specific reference to electromyographic studies

Tibialis posterior has a vital role during gait as the primary dynamic stabiliser of the medial longitudinal arch; however, the muscle and tendon are prone to dysfunction with several conditions. We present an overview of tibialis posterior muscle and tendon anatomy with images from cadaveric work on fresh frozen limbs and a review of current evidence that define normal and abnormal tibialis posterior muscle activation during gait. A video is available that demonstrates ultrasound guided intra-muscular insertion techniques for tibialis posterior electromyography.Current electromyography literature indicates tibialis posterior intensity and timing during walking is variable in healthy adults and has a disease-specific activation profile among different pathologies. Flat-arched foot posture and tibialis posterior tendon dysfunction are associated with greater tibialis posterior muscle activity during stance phase, compared to normal or healthy participants, respectively. Cerebral palsy is associated with four potentially abnormal profiles during the entire gait cycle; however it is unclear how these profiles are defined as these studies lack control groups that characterise electromyographic activity from developmentally normal children. Intervention studies show antipronation taping to significantly decrease tibialis posterior muscle activation during walking compared to barefoot, although this research is based on only four participants. However, other interventions such as foot orthoses and footwear do not appear to systematically effect muscle activation during walking or running, respectively. This review highlights deficits in current evidence and provides suggestions for the future research agenda.

Gait patterns in subjects with rheumatoid arthritis cannot be explained by reduced speed alone

The aim of this study was to investigate the characteristics of gait in subjects with rheumatoid arthritis (RA) by comparing gait parameters obtained from these subjects and controls. Seventeen subjects with RA in functional class II (mean age 51.1 years, S.D. 6.2 years) and 20 controls (mean age 50.4 years, S.D. 5.3 years) were instructed to walk a straight walkway at five different self-selected speeds. Speed-dependent variables were analysed by an interpolation procedure to estimate scores at a normalized speed of 0.8m/s. At self-selected speed the RA group walked significantly slower, with a shorter step length and longer stance phase. There was no difference in cadence and step width. When controlling for speed, the RA group walked with shorter step length (p=0.04) and higher cadence (p=0.03) compared to controls, but no significant difference in stand phase and step width was found. The present study demonstrates that speed-dependent gait variables are affected when controlling for the effect of speed in subjects with RA. In further studies of gait, speed should be controlled for.

Characterising the clinical and biomechanical features of severely deformed feet in rheumatoid arthritis

PURPOSE

Foot deformity is a well-recognised impairment in patients with rheumatoid arthritis (RA) which results in functional disability. Deformity can occur at the rearfoot, midfoot, forefoot or in combination and the impact that site-specific foot deformities has on functional disability is largely unknown. The aim of this study was to describe the clinical and biomechanical characteristics of patients with severe rearfoot, forefoot or combined deformities and determine localised disease impact.

METHODS

Twenty-eight RA patients with severe forefoot (FF group n=12), rearfoot (RF group n=10) or combined deformities (COMB group n=6) were recruited. Each patient underwent 3D gait analysis and plantar pressure measurements. Localised disease impact and foot-specific disease activity were determined using the Leeds Foot Impact Scale and clinical examination respectively. Comparison was made against a normative control group (n=53).

RESULTS

Patients in the COMB group walked slowest and the double-support time was longer in the RF and COMB groups compared to those in the FF group. Patients in the RF and COMB group had higher levels of foot-related disability and demonstrated excessive rearfoot eversion and midfoot collapse compared to those in the FF group. Forefoot deformity was associated with reduced toe contact, high forefoot pressures and delayed heel lift.

CONCLUSIONS

Abnormal gait patterns were identified and were distinguishable among those patients with predominantly forefoot, rearfoot or combined foot deformity.

Gait pattern in rheumatoid arthritis

The purpose of this study was to analyse kinematic and kinetic gait changes in rheumatoid arthritis (RA) patients in comparison to healthy controls and to examine whether levels of functional disability (Health Assessment Questionnaire (HAQ)-scores) were associated with gait parameters. Using a three-dimensional motion analysis system, kinematic and kinetic gait parameters were measured in 50 RA patients and 37 healthy controls. There was a significant reduction in joint motions, joint moments and work in the RA cohort compared with healthy controls. The following joint motions were decreased: hip flexion-extension range (Delta6 degrees ), hip abduction (Delta4 degrees ), knee flexion-extension range (Delta8 degrees ) and ankle plantarflexion (Delta10 degrees ). The following joint moments were reduced: hip extensor (Delta0.30Nm/kg) and flexor (Delta0.20Nm/kg), knee extensor (Delta0.11Nm/kg) and flexor (Delta0.13Nm/kg), and ankle plantarflexor (Delta0.44Nm/kg). Work was lower in hip positive work (Delta0.07J/kg), knee negative work (Delta0.08J/kg) and ankle positive work (Delta0.15J/kg). Correlations were fair although significant between HAQ and hip flexion-extension range, hip abduction, knee flexion-extension range, hip abductor moment, stride length, step length and single support (r=-0.30 to -0.38, p<0.05). Our findings suggest that RA patients have overall less joint movement and specifically restricted joint moments and work across the large joints of the lower limbs during walking than healthy controls. There were only fair associations between levels of functional disability and gait parameters. The findings of this study help to improve the understanding how RA affects gait changes in the lower limbs.

Assessment of foot impairment in rheumatoid arthritis patients by dynamic pedobarography

OBJECTIVES

Impaired foot function may jeopardize the mobility of patients with rheumatoid arthritis (RA). However, there are still no guidelines concerning the adequate early treatment of painful rheumatoid feet which do not yet require surgery. An assessment method for RA feet appears necessary in order to detect foot problems before functional limitations develop. Therefore, the aim of the present study was to evaluate the use of pedobarographic measurements for detecting changes in plantar loading characteristics and their relationship to foot pain in patients with RA.

METHODS

One hundred and twelve patients with RA (55.0+/-11.0 years of age) were divided into three groups according to their Health Assessment Questionnaire (HAQ) Score and compared to a control group of 20 healthy adults (CG). Thirty-six patients with good physical capacity belonged to group 1 (RA1; HAQ-score: 0-1.0), 38 patients with moderate capacity to group 2 (RA2; score: 1.1-2.0) and 38 patients with low capacity to group 3 (RA3; score: 2.1-3.0). Each patient's foot pain was clinically assessed. Pedobarography was used to analyze foot loading parameters while walking barefoot.

RESULTS

In the forefoot, average pressures under the lateral forefoot were higher in RA1 patients than in RA2 patients and controls (p<0.05) despite an inconspicuous clinical examination of the foot in RA1 patients. RA1 patients also demonstrated higher plantar pressures than RA2 under the second metatarsal head (p<0.05). In contrast, no significant differences in maximum force could be demonstrated between patient groups. Furthermore, in RA3 patients with lower physical capacity, foot pain was increased as compared to RA1 and RA2 patients.

CONCLUSION

In RA patients, pedobarographic patterns show specific changes which characterize the level of functional capacity. In patients with foot involvement, pedobarographic measurements can be useful during the earlier stages of the disease, when clinical examination does not yet indicate the need for more aggressive treatment or orthopedic interventions.

A multisegmental foot model with bone-based referencing: sensitivity to radiographic input parameters

We present a new kinematic model measuring the three-dimensional orientation of multiple segments of the foot and ankle. The model defines neutral alignments based on the alignments of the underlying bony segments, and indexes the orientation of skin-mounted markers to the bony anatomy using measures from weightbearing x-rays. The sensitivity of the model to these radiographic input parameters was analyzed using data from walking trials. Kinematic output in each plane was found to be most sensitive to perturbations of radiographic measurements in that same plane; however, perturbations in the coronal and transverse planes demonstrated significant carry-over into other planes. The analysis highlights the importance of accurately accounting for the underlying anatomy in measuring intersegmental kinematics.

Forefoot, rearfoot and shank coupling: effect of variations in speed and mode of gait

BACKGROUND

Although there is a wealth of research into the kinematic coupling between the foot and shank, it remains unclear whether the relationship is stable across speed and mode of gait. The aim of this study was to determine whether the coupling relationship between the forefoot, rearfoot and shank differed between walking and running, and across different running speeds.

METHODS

Twelve subjects walked/ran barefoot over-ground at one walking and three running speeds. The shank, rearfoot and forefoot were modelled as rigid segments and three-dimensional joint kinematics were determined using a seven camera ProReflex system. Coupling between the forefoot, rearfoot and shank was assessed using cross-correlation and vector coding techniques.

FINDINGS

Cross-correlation of rearfoot eversion/inversion with shank internal/external rotation was lower in walking (r=0.49) compared to running (r>0.95). This was also the case between rearfoot frontal plane and forefoot sagittal plane motion (walking, r=-0.80; running, r=-0.96). Rearfoot frontal plane and forefoot transverse plane cross-correlation was high in both running and walking (r>0.90), but there was little evidence of any coupling between rearfoot frontal plane and forefoot frontal plane motion in any condition. No differences in cross-correlations were found between the three running speeds.

INTERPRETATION

Kinematic coupling between the forefoot, rearfoot and shank was weak during walking relative to running. In particular, the low cross-correlation between rearfoot eversion/inversion and shank internal/external rotation during walking implies the two motions are not rigidly linked, as has been assumed in previous injury models.

The impact of rheumatoid arthritis on foot function in the early stages of disease: a clinical case series

Background

Foot involvement occurs early in rheumatoid arthritis but the extent to which this impacts on the structure and function leading to impairment and foot related disability is unknown. The purpose of this study was to compare clinical disease activity, impairment, disability, and foot function in normal and early rheumatoid arthritis (RA) feet using standardised clinical measures and 3D gait analysis.

Methods

Twelve RA patients with disease duration ≤2 years and 12 able-bodied adults matched for age and sex underwent 3D gait analysis to measure foot function. Disease impact was measured using the Leeds Foot impact Scale (LFIS) along with standard clinical measures of disease activity, pain and foot deformity. For this small sample, the mean differences between the groups and associated confidence intervals were calculated using the t distribution

Results

Moderate-to-high foot impairment and related disability were detected amongst the RA patients. In comparison with age- and sex-matched controls, the patients with early RA walked slower (1.05 m/s Vs 1.30 m/s) and had a longer double-support phase (19.3% Vs 15.8%). In terminal stance, the heel rise angle was reduced in the patients in comparison with normal (-78.9° Vs -85.7°). Medial arch height was lower and peak eversion in stance greater in the RA patients. The peak ankle plantarflexion power profile was lower in the patients in comparison with the controls (3.4 W/kg Vs 4.6 W/kg). Pressure analysis indicated that the RA patients had a reduced lesser toe contact area (7.6 cm² Vs 8.1 cm²), elevated peak forefoot pressure (672 kPa Vs 553 kPa) and a larger mid-foot contact area (24.6 cm² Vs 19.4 cm²).

Conclusion

Analysis detected small but clinically important changes in foot function in a small cohort of RA patients with disease duration <2 years. These were accompanied by active joint disease and impairment and disability.

Repeatability of a model for measuring multi-segment foot kinematics in children

This study used a previously tested foot model and adapted it for use with children. A number of variations on this adapted model were implemented and tested for repeatability and accuracy on 15 healthy children on three occasions. These included redefinition of the long axes of the tibia and forefoot, assessment of the flexibility of the forefoot and evaluation of the variability of the wand marker on the heel for both static and dynamic trials. It was found that variations on the model produced only minimal changes in repeatability, the only significant change being elimination of the wand marker on the heel in the static trial, which reduced between-day variability of hindfoot motion in the transverse plane. However, some differences were evident in the mean values for all variations. Based on these results, the most accurate and appropriate version of the model is proposed, and average kinematic curves are presented based on the measurements from 14 healthy children.

Effect of a high-intensity weight-bearing exercise program on radiologic damage progression of the large joints in subgroups of patients with rheumatoid arthritis

OBJECTIVE

To investigate whether a high-intensity exercise program accelerates the rate of radiologic damage of the large joints in predefined subgroups of patients with rheumatoid arthritis.

METHODS

The data of 277 participants in a 2-year randomized controlled trial, comparing the effects of high-intensity exercises with usual care, were used. Linear regression analysis was used to test which predefined variables at baseline (age, disease duration, disease activity, physical capacity, functional ability, joint damage) modified the effect of high-intensity exercise on the progression of radiologic damage of the large joints over 24 months.

RESULTS

Baseline radiologic joint damage was the only variable associated with the effect of high-intensity exercise on joint damage progression in large joints. In a subgroup of 218 patients with no or little joint damage (defined as Larsen score < or = 5; 80% of our study population) the proportions of patients with an increase in joint damage were similar for the exercise and usual-care group (35% versus 36%, risk ratio [RR] 1.0 [0.7-1.4]; P = not significant), whereas, in a subgroup of 59 patients who already had extensive damage of large joints (defined as Larsen score >5) the proportion was significantly higher in the exercise group (85% versus 48%, RR 1.8 [1.2-2.6]; P < 0.05).

CONCLUSION

High-intensity weight-bearing exercises appear to accelerate joint damage progression in patients with preexisting extensive damage. Patients with extensive large joint damage should, therefore, be advised to refrain from activities excessively loading the damaged joints.

Pes planovalgus in RA: a descriptive and analytical study of foot function determined by gait analysis

OBJECTIVE

To compare gait and foot function between rheumatoid arthritis (RA) patients with painful pes planovalgus deformity and healthy age- and sex-matched adults.

METHODS

Gait analysis was undertaken in 23 RA patients (14 female and 9 male, mean age 52.3 years, mean disease duration 6.6 years) and 23 healthy adults (14 female and 9 male, mean age 49.5 years). Gait measurements included temporal and spatial parameters, plantar pressures and three-dimensional (3D) kinematics at the ankle joint complex (AJC). The mean differences between the groups and associated confidence intervals were calculated using the t distribution.

RESULTS

RA patients showed longer gait cycle (mean difference 0.15 sec and 0.14 sec for right and left limbs, respectively) and double-limb support times (mean difference 8.3% and 7.9% for right and left limbs, respectively), shorter stride length (mean difference -0.31 m for right and left limbs), slower walking speed (mean difference -0.39 m/sec) and lower cadence (mean difference -16.6 steps/min). In comparison with the normal group, RA patients had greater AJC dorsi/plantarflexion range of motion (ROM) (mean difference 5.7 ( degrees )) and inversion/eversion ROM (mean difference 2.9 ( degrees )). The frontal plane position of the AJC was more everted at specific stance periods (mean difference at heel strike -2.4 ( degrees ) and at midstance -4.0( degrees )). Furthermore, both the peak eversion (mean difference -4.1 ( degrees )) and summated eversion motion as a function of time (mean difference -313.9 ( degrees )) were greater in the RA group. The pes planovalgus foot in RA was characterized by increases in peak pressure (mean difference 34.3 kPa), pressure-time integral (mean difference 18.2 kPa.sec), peak force (mean difference 1.7 N), force-time integral (mean difference 0.7 N.sec), contact time (mean difference 9.8% roll over process) and contact area (mean group difference 3.4 cm(-2)) in the medial midfoot. Further changes in the load pattern in the forefoot were observed in the RA patients, namely increases in the peak pressure (mean difference 96.4 kPa), pressure-time integral (mean difference 58.4 kPa.sec), and contact area (mean difference 1.7 cm(-2)) in the medial forefoot region and reduction in contact area (mean difference -3.9 cm(-2)), peak force (mean difference -7.2 N) and force-time integral (mean difference -1.6 N.sec) in the lateral forefoot.

CONCLUSIONS

Painful pes planovalgus deformity in RA is associated with global changes in gait, and localized structural and functional changes in the foot which can be accurately measured using clinical gait analysis.