Effects of hallux limitus on plantar foot pressure and foot kinematics during walking

Evaluation of Gait Parameters on Subjects with Hallux Limitus Using an Optogait Sensor System: A Case-Control Study

Background and Objetives: The foot is a part of the body's kinetic chain and needs to be efficient during the entire gait cycle. Electronic Sensor Gait analysis is useful and an important tool within the area of podiatry to assess the physical state of patients that helps the comprehensive intervention in situations where the daily activity is limited. The aim of this research is to evaluate if the presence of a hallux limitus (HL) can alter gait space-time parameters and consequently can affect the take-off phase of the gait and the limitation of the range of motion (ROM) of the hallux. Materials and Methods: A case-control study was designed to verify whether there are alterations in the spatiotemporal parameters of the gait cycle between subjects with structural HL compared to the group of subjects with a normal hallux range. A total of n = 138 participants, cases (68 HL subjects) and healthy controls (70 subjects) were studied using an OptoGait LED sensor system to identify gait imbalances using OptoGait photocell gait analysis sensors. Results: Significant differences were found between the two groups with respect to stride length, gait cycle duration in seconds (for both feet) and for total stride and load response (p < 0.05). Conclusions: The limitation of the Hallux ROM may alter the normal gait patterns measured with an Optogait system. The early identification and treatment of gait disturbances due to HL are important to achieve normal gait physical activity to maintain a healthy lifestyle.

Hallux Limitus Influence on Plantar Pressure Variations during the Gait Cycle: A Case-Control Study

BACKGROUND

Hallux limitus is a common foot disorder whose incidence has increased in the school-age population. Hallux limitus is characterized by musculoskeletal alteration that involves the metatarsophalangeal joint causing structural disorders in different anatomical areas of the locomotor system, affecting gait patterns. The aim of this study was to analyze dynamic plantar pressures in a school-aged population both with functional hallux and without.

METHODS

A full sample of 100 subjects (50 male and 50 female) 7 to 12 years old was included. The subjects were identified in two groups: the case group (50 subjects characterized as having hallux limitus, 22 male and 28 female) and control group (50 subjects characterized as not having hallux limitus, 28 male and 22 female). Measurements were obtained while subjects walked barefoot in a relaxed manner along a baropodometric platform. The hallux limitus test was realized in a seated position to sort subjects out into an established study group. The variables checked in the research were the surface area supported by each lower limb, the maximum peak pressure of each lower limb, the maximum mean pressure of each lower limb, the body weight on the hallux of each foot, the body weight on the first metatarsal head of each foot, the body weight at the second metatarsal head of each foot, the body weight at the third and fourth metatarsal head of each foot, the body weight at the head of the fifth metatarsal of each foot, the body weight at the midfoot of each foot, and the body weight at the heel of each foot.

RESULTS

Non-significant results were obtained in the variable of pressure peaks between both study groups; the highest pressures were found in the hallux with a p-value of 0.127 and in the first metatarsal head with a p-value 0.354 in subjects with hallux limitus. A non-significant result with a p-value of 0.156 was obtained at the second metatarsal head in healthy subjects. However, significant results were observed for third and fourth metatarsal head pressure in healthy subjects with a p-value of 0.031 and regarding rearfoot pressure in subjects with functional hallux limitus with a p-value of 0.023.

CONCLUSIONS

School-age subjects with hallux limitus during gait exhibit more average peak plantar pressure in the heel and less peak average plantar pressure in the third and fourth metatarsal head as compared to healthy children aged between 7 and 12 years old.

Analysis of Static Plantar Pressures in School-Age Children with and without Functional Hallux Limitus: A Case-Control Study

BACKGROUND

The presence of hallux limitus in adulthood is frequently encountered in clinical practice, generating other biomechanical, structural, and functional compensations in dynamics secondary to blockage of the main pivot in the sagittal plane, the first metatarsophalangeal joint. In addition, the presence of functional hallux limitus (FHL) in school-age children is also increasing. Currently, there is a lack of scientific literature about this condition in the pediatric population, and early diagnosis is necessary to reduce future biomechanical disorders and avoid the development of foot arthritis. The purpose of this research was to identify static plantar pressures in school-age children with and without hallux limitus.

METHODS

A total sample of 106 children aged between six and twelve years old was divided into two groups: the case group (53 subjects with functional hallux limitus) and the control group (53 subjects without functional hallux limitus). Data were acquired with the participants in a standing barefoot position on the pressure platform, and the hallux limitus functional test was performed in a sitting position to classify the individuals into the determined study group. The variables analyzed in the research were: plantar pressure, bilateral forefoot and rearfoot surface area, bilateral forefoot and rearfoot ground reaction forces, bilateral forefoot and rearfoot distribution of body weight, total left and right surface area, maximum pressure of the left foot and right foot, medium pressure of the left foot and right foot, ground reaction forces of the left foot and right foot, and the weight of each foot.

RESULTS

Age was the only descriptive quantitative variable that showed a significant difference between the two study groups, with a p-value of 0.031. No statistically significant differences were found between groups in the bilateral forefoot and rearfoot surface area, ground reaction forces, distribution of body weight, or maximum and medium plantar pressure in the left and right foot.

CONCLUSIONS

Changes in the location of the maximum pressure were observed, particularly in older participants with FHL, but these results were not significant. The findings of this study did not show significant differences between the static plantar pressures of school-age individuals with and without functional hallux limitus.

Morton’s Extension on Hallux Rigidus Pathology

Study design, case-control study: Background, Morton’s extension (ME) is a kind of orthotic that has been used as a conservative treatment of painful hallux rigidus (HR) osteoarthritis, but only their effects on first metatarsophalangeal joint (MPJ) mobility and position in healthy subjects have been studied, but not on its applied pulled tension forces neither in subjects with HR. Objectives: This study sought to understand how ME’s orthotics with three different thicknesses could influence the kinematic first MPJ by measuring hallux dorsiflexion using Jack’s test and a digital algometer with a rigid strip anchored to the iron hook’s extremity and comparing subjects with healthy first MPJ mobility to those with HR. We aimed to clarify whether tension values were different between healthy and HR subjects. Methods: Fifty-eight subjects were selected, of whom thirty were included in the case group according to HR criteria and twenty-eight were included in the control group. A digital algometer (FPX®® 25, Wagner Instruments®®, Greenwich, CT, USA) was used to assess the pulled tension values (kgf) of the first MPJ during Jack’s test. Results: The pulled tension values were highly reliable (ICC > 0.963). There were no statistically significant differences between the pulled tension values for the different ME conditions in the case (p = 0.969) or control (p = 0.718) groups. However, as it’s expected, there were statistically significant differences comparing all pulled tension values between case and control group subjects (p < 0.001). Conclusions: Different ME’s thicknesses had no influence on the pulled effort applied during the dorsiflexion Jack’s test between the healthy and HR groups; therefore, it can be prescribed without joint-care danger. In addition, it is proven that there is greater resistance to performing Jack’s test in the HR group than in the healthy group, regardless of ME’s orthotics. Furthermore, it is shown that the digital algometer device is a valid tool to detect the first MPJ restriction and is more reliable than other tests.

Application of Biomechanics in Treating the Athlete: The All Important Measurements of Relaxed Calcaneal Stance Position, Achilles Flexibility, and First Ray Range of Motion

Biomechanics is a crucial component of treating lower extremity pathology. The relaxed calcaneal stance position, the Achilles flexibility, and the first ray motion and position tests are demonstrated and should be mastered. The relaxed calcaneal stance position is crucial in children's flat feet treatment, adult acquired flat feet, and all pronatory symptoms. The Achilles flexibility measurement demonstrates normality, tightness, or overflexibility. Tightness and overflexibility denote weakness owing to the contractile properties of the tendon. The first ray motion and position examination elucidates whether the first ray is normal or part of a pronatory problem or a supinatory problem.

Gait analysis of foot compensation in symptomatic Hallux Rigidus patients

BACKGROUND

Compensatory motion of foot joints in hallux rigidus (HR) are not fully known. This study aimed to clarify the kinematic compensation within the foot and to detect whether this affects plantar pressure distribution.

METHODS

Gait characteristics were assessed in 16 patients (16 feet) with HR and compared with 15 healthy controls (30 feet) with three-dimensional gait analysis by using the multi-segment Oxford Foot Model, measuring spatio-temporal parameters, joint kinematics and plantar pressure.

RESULTS

HR subjects showed less hallux plantar flexion during midstance and less hallux dorsiflexion during push-off, while increased forefoot supination was detected during push-off. No significant differences in plantar pressure were detected. Step length was significantly smaller in HR subjects, while gait velocity was comparable between groups.

CONCLUSIONS

HR significantly affects sagittal hallux motion, and the forefoot compensates by an increased supination during push-off. Despite this kinematic compensatory mechanism, no significant differences in plantar loading were detected.

International Foot and Ankle Osteoarthritis Consortium review and research agenda for diagnosis, epidemiology, burden, outcome assessment and treatment

OBJECTIVE

To summarise the available evidence relating to the diagnosis, epidemiology, burden, outcome assessment and treatment of foot and ankle osteoarthritis (OA) and to develop an agenda to guide future research.

METHOD

Members of the International Foot and Ankle Osteoarthritis Consortium compiled a narrative summary of the literature which formed the basis of an interactive discussion at the Osteoarthritis Research Society International World Congress in 2021, during which a list of 24 research agenda items were generated. Following the meeting, delegates were asked to rank the research agenda items on a 0 to 100 visual analogue rating scale (0 = not at all important to 100 = extremely important). Items scoring a mean of 70 or above were selected for inclusion.

RESULTS

Of the 45 delegates who attended the meeting, 31 contributed to the agenda item scoring. Nineteen research agenda items met the required threshold: three related to diagnosis, four to epidemiology, four to burden, three to outcome assessment and five to treatment.

CONCLUSIONS

Key knowledge gaps related to foot and ankle OA were identified, and a comprehensive agenda to guide future research planning was developed. Implementation of this agenda will assist in improving the understanding and clinical management of this common and disabling, yet relatively overlooked condition.

Gait and Balance Biomechanical Characteristics of Patients With Grades III and IV Hallux Rigidus

Patients with hallux rigidus (HR) tend to develop a characteristic alteration in walking to lessening pain and compensate for the limited range of motion at the first metatarsophalangeal (MTP1) joint that might be affected balance and gait. The goal of this study was to perform an integrated biomechanical description of gait and balance of symptomatic patients with either grade as III or IV HR in comparison with healthy subjects. Eleven patients (7 men) with HR (60 ± 7 years, 1.60 ± 0.07 m, and 70 ± 13 kg) and 16 (7 men) healthy subjects (70 ± 8 years, 1.66 ± 0.10 m, and 74 ± 14 kg) were included. Subjects performed 2 tasks: walking (5 trials of straight walking for at least 6 meters) and bipedal quiet standing for 30 seconds. For these 2 tasks the following variables were measured: range of motion of the MTP1 joint, plantar pressure distribution during the stance phase of walking, and the postural sway during quiet standing. Plantar pressure was measured in up 15 walking trials with a mat pressure sensor. The MTP1 joint range of motion for flexion/extension during walking was significantly smaller for the patients with HR than for the control group (HR: 14 ± 8°, control: 44 ± 5°; t(17) = -9.7, p < .001). The forefoot plantar pressure distribution among different regions of the foot in patients with HR was not statistically different than the control group, but there was a tendency of higher pressures in the lateral metatarsal heads (p = .06). As description of the postural sway during quiet standing, the center of pressure area was not different between HR and the control group (p > .05). Decreased MTP1 joint range of motion for flexion/extension during walking in symptomatic high-grade HR patients can be associated with higher pressure in the lateral metatarsal heads while the impact on postural sway is not affected.

Pathophysiological Behaviour of the Climber's Foot versus the General Population: A Prospective Observational Study

Sport climbing is becoming increasingly popular, with people of all types and ages practising it. The feet suffer a lot of pressure with the sport climbing gesture, which in the long run can produce alterations in the first metatarsophalangeal joint or in the first radius of the foot. Objective: To observe and quantify the behaviour of the foot in climbing subjects compared to a group of non-climbing subjects, comparing the pressures, first metatarsophalangeal joint and first radius of the foot. Method: This is a non-experimental and observational, cross-sectional, descriptive and prospective research. The study sample consisted of 105 subjects (42 males and 63 females). The control group consisted of 52 subjects and the climbing group consisted of 53 subjects. Different exploratory tests were carried out on all the subjects, such as: mobility of the metatarsophalangeal joint and first radius of the foot and the study of plantar pressures in different areas of the study. Results: No significant difference was found between left and right foot measurements (p > 0.05). The pressures of the same foot are significant, both at static and dynamic stages for both groups. The maximum pressure in the climbing group was under the first metatarsal head, while in the control group it was under the second metatarsal head. There were significant differences in the mobility of the first metatarsal joint and the first radius between the two groups. Conclusion: It can be seen that the group of climbers has less plantar pressure than the control group. They also have altered mobility of the first radius and the first metatarsophalangeal joint.

The effect of lengthening the gastrocnemius muscle in chronic therapy resistant plantar fasciitis

BACKGROUND

The aetiology of chronic therapy resistant plantar fasciitis (CTRPF) is multifactorial with more focus in recent times on the gastroc-soleus complex. This study evaluates the effect of lengthening the gastrocnemius muscle in CTRPF.

METHODS

All patients with CRTPF complaints for at least one year underwent the same standard conservative treatment prior to surgery. 32 patients failed this treatment and underwent gastrocnemius recession. Silfverskiöld test, questionnaires and plantar pressure measurements were obtained at 5 visits.

RESULTS

One year follow up showed a significantly increase in dorsiflexion of the ankle (16 degrees), a decrease in VAS; 78 (SD: 19) to 20 (SD: 24) and significant improved functional scores. Plantar pressure measurements showed an increase of pressure under the medial proximal part of the midfoot and the 1 st metatarsal and a decrease under the hallux.

CONCLUSIONS

A gastrocnemius recession results in a significant gain in dorsiflexion, altered loading of the foot and good clinical outcome in patients with CTRPF.

LEVEL OF EVIDENCE

Level 2.

Mid-Term Functionality and Survival of 116 HemiCAP® Implants for Hallux Rigidus

Hallux rigidus can be treated with a proximal hemiarthroplasty (HemiCAP®) to preserve the motion in the first metatarsophalangeal joint and reduce pain. This study examines the functionality, and survival rates of HemiCAP® implants, with or without a dorsal flange. One hundred and five patients were treated with a HemiCAP® (N = 116 HemiCAPs®) between 2006 and 2014. Revision rates, arthrosis score, hallux valgus (HV), intermetatarsal (IM), distal metaphyseal articular angle (DMAA), visual analog scale (VAS) (1-10 points), American Orthopaedic Foot and Ankle Score (AOFAS) MTP-IP (AOFAS 0-100 points), SF-12, range of motion (ROM), and radiographs were analyzed pre- and postoperatively. Statistics: Kaplan-Meier survival analysis, Cox-regression, and paired t tests. At 2, 4, and 6 years, the implant survival was 87%, 83%, and 81%, respectively. All revised due to pain. Dorsal flange, gender, arthrosis, HV, IM, and DMAA did not influence the results. At the mean 5-year follow-up (n = 47) median (range) dorsal ROM was 45° (10°-75°), AOFAS was mean 87.2 ± 10.8, VAS was 2 ± 1.6, and SEFAS was 42 ± 6 points. The dorsal flange made no significant difference for ROM or patient-reported outcome measures compared to the HemiCAP® with no dorsal flange. Twenty-three patients with preoperative data were re-examined, and preoperative dorsal ROM mean difference (confidence interval [CI]) increased 20.7° (13.9°-27.4°), VAS decreased with a mean difference (CI) of -4.7 (-5.8 to 3.5), and AOFAS increased with a mean difference (CI) 26.2 (20.2-32.2) (for all p < .001). The 6-year survival rate of the HemiCAP® implant was 81%. The design change to dorsal flange was not evident clinically. Unrevised patients had significantly less pain, greater ROM, and better foot and ankle function than preoperatively.

Plantar forces mid-term after hemiarthroplasty with HemiCAP for hallux rigidus

BACKGROUND

The aim of this study was to examine the biomechanical gait effects and range of motion following a proximal hemiarthroplasty with a HemiCap®.

METHODS

Forty-one HemiCAP-operated participants with a mean follow-up time of 5 years had plantar force variables (PFVs) examined and compared with their non-operated foot and a control group. PFVs were compared to the MTPJ1 range of motion (ROM), and pain measured by Visual Analog Scale (VAS).

RESULTS

The HemiCAP participants' operated feet had higher PFVs laterally on the foot and lower PFVs under the hallux. Dorsal ROM of the operated feet was a median 45° (range 10-75) by goniometer and 41.5 (range 16-80) by X-ray. An increase in ROM decreased the forces under the hallux. Most participants were pain-free. No correlation between pain and PFVs was found.

CONCLUSIONS

Increased dorsiflexion decreased the maximum force under the hallux. A mid-term HemiCAP maintains some motion. The decreased PFVs under the hallux may reflect a patient reluctance to load the first ray, although no correlation between plantar forces and pain was found.

Reliability Study of Diagnostic Tests for Functional Hallux Limitus

BACKGROUND

Functional hallux limitus (FHL) refers to dorsiflexion hallux mobility limitation when the first metatarsal head is under loading conditions but not in the unloaded state. The goal of the study was to evaluate 3 common manual tests (Buell, Dananberg, and Jack tests) for assessing first metatarsophalangeal joint (MPJ) mobility and determining the normal values needed to detect FHL, and clarify the signs and symptoms associated with this pathology.

METHODS

Forty-four subjects were included in this reliability study. Subjects were divided into healthy control (non-FHL) and FHL groups according to the Buell first MPJ limitation values in addition to signs and symptoms derived from the literature. In both groups, we measured the mobility in the Buell, Dananberg, and Jack tests using a goniometer; their intraclass correlation coefficients (ICCs), sensitivities, and specificity indexes were also calculated.

RESULTS

All techniques showed high reliability across measurement trials with ICCs ranging from 0.928 to 0.999. The optimal mobility grades for predicting FHL were 68.6 ± 3.7 degrees, 21 ± 5.9 degrees, and 25.5 ± 6.5 degrees (mean±SD) (P < .05) for the Buell, Dananberg, and Jack tests, respectively.

CONCLUSION

Normal and limited mobility values were established for assessing FHL using each technique. The sensitivity and specificity data were perfect for the Dananberg and Jack tests, thus identifying these tests as specific and valid tools for use in FHL diagnosis. Pinch callus was the sign most associated with FHL.

LEVEL OF EVIDENCE

Level II, comparative series.

Multi-segment foot models and their use in clinical populations

BACKGROUND

Many multi-segment foot models based on skin-markers have been proposed for in-vivo kinematic analysis of foot joints. It remains unclear whether these models have developed far enough to be useful in clinical populations. The present paper aims at reviewing these models, by discussing major methodological issues, and analyzing relevant clinical applications.

RESEARCH QUESTION

Can multi-segment foot models be used in clinical populations?

METHODS

Pubmed and Google Scholar were used as the main search engines to perform an extensive literature search of papers reporting definition, validation or application studies of multi-segment foot models. The search keywords were the following: 'multisegment'; 'foot'; 'model'; 'kinematics', 'joints' and 'gait'.

RESULTS

More than 100 papers published between 1991 and 2018 were identified and included in the review. These studies either described a technique or reported a clinical application of one of nearly 40 models which differed according to the number of segments, bony landmarks, marker set, definition of anatomical frames, and convention for calculation of joint rotations. Only a few of these models have undergone robust validation studies. Clinical application papers divided by type of assessment revealed that the large majority of studies were a cross-sectional comparison of a pathological group to a control population.

SIGNIFICANCE

This review suggests that there is sufficient evidence that multi-segment foot models may be successfully applied in clinical populations. Analysis of the currently available models allows users to better identify the most suitable protocol for specific clinical applications. However new models require thorough validation and assessment before being used to support clinical decisions.

Centre of pressure characteristics during walking in individuals with and without first metatarsophalangeal joint osteoarthritis

OBJECTIVE

The objective of this study was to compare centre of pressure characteristics during walking in individuals with and without first metatarsophalangeal joint osteoarthritis (1st MTPJ OA), in order to provide insights into alterations in foot function associated with this condition.

METHODS

Twenty people with 1st MTPJ OA and 20 asymptomatic controls matched for age, sex and body mass index underwent gait analysis using the emed^®-x400 plantar pressure system (Novel GmbH, Germany). Average and maximum centre of pressure velocity and lateral-medial force index during loading, midstance, terminal stance and preswing were compared between the groups.

RESULTS

During the preswing phase of gait, maximum centre of pressure velocity was significantly slower in individuals with 1st MTPJ OA (0.78 ± 0.19 vs 1.13 ± 0.36 m/sec; p = 0.003), and both average and maximum lateral-medial force indices were significantly higher in individuals with 1st MTPJ OA (0.98 ± 0.14 vs 0.82 ± 0.13; p < 0.001 and 1.37 ± 0.29 vs 1.15 ± 0.15; p = 0.008, respectively). Non-weightbearing 1st MTPJ dorsiflexion range of motion was significantly associated with maximum centre of pressure velocity (r = 0.54, p < 0.001) and average lateral-medial force index (r = -0.44, p = 0.004) during preswing.

CONCLUSIONS

Individuals with 1st MTPJ OA exhibit significant differences in centre of pressure characteristics during propulsion, possibly due to decreased range of available 1st MTPJ dorsiflexion.

Shoe-stiffening inserts for first metatarsophalangeal joint osteoarthritis (the SIMPLE trial): study protocol for a randomised controlled trial

BACKGROUND

This article describes the design of a parallel-group, participant- and assessor-blinded randomised controlled trial comparing the effectiveness of shoe-stiffening inserts versus sham shoe insert(s) for reducing pain associated with first metatarsophalangeal joint (MTPJ) osteoarthritis (OA).

METHODS

Ninety participants with first MTPJ OA will be randomised to receive full-length shoe-stiffening insert(s) (Carbon Fibre Spring Plate, Paris Orthotics, Vancouver, BC, Canada) plus rehabilitation therapy or sham shoe insert(s) plus rehabilitation therapy. Outcome measures will be obtained at baseline, 4, 12, 24 and 52 weeks; the primary endpoint for assessing effectiveness being 12 weeks. The primary outcome measure will be the foot pain domain of the Foot Health Status Questionnaire (FHSQ). Secondary outcome measures will include the function domain of the FHSQ, severity of first MTPJ pain (using a 100-mm Visual Analogue Scale), global change in symptoms (using a 15-point Likert scale), health status (using the Short-Form-12® Version 2.0 and EuroQol (EQ-5D-5L™) questionnaires), use of rescue medication and co-interventions, self-reported adverse events and physical activity levels (using the Incidental and Planned Activity Questionnaire). Data will be analysed using the intention-to-treat principle. Economic analysis (cost-effectiveness and cost-utility) will also be performed. In addition, the kinematic effects of the interventions will be examined at 1 week using a three-dimensional motion analysis system and multisegment foot model.

DISCUSSION

This study will determine whether shoe-stiffening inserts are a cost-effective intervention for relieving pain associated with first MTPJ OA. The biomechanical analysis will provide useful insights into the mechanism of action of the shoe-stiffening inserts.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry, identifier: ACTRN12616000552482 . Registered on 28 April 2016.

Challenging the foundations of the clinical model of foot function: further evidence that the root model assessments fail to appropriately classify foot function

BACKGROUND

The Root model of normal and abnormal foot function remains the basis for clinical foot orthotic practice globally. Our aim was to investigate the relationship between foot deformities and kinematic compensations that are the foundations of the model.

METHODS

A convenience sample of 140 were screened and 100 symptom free participants aged 18-45 years were invited to participate. The static biomechanical assessment described by the Root model was used to identify five foot deformities. A 6 segment foot model was used to measure foot kinematics during gait. Statistical tests compared foot kinematics between feet with and without foot deformities and correlated the degree of deformity with any compensatory motions.

RESULTS

None of the deformities proposed by the Root model were associated with distinct differences in foot kinematics during gait when compared to those without deformities or each other. Static and dynamic parameters were not correlated.

CONCLUSIONS

Taken as part of a wider body of evidence, the results of this study have profound implications for clinical foot health practice. We believe that the assessment protocol advocated by the Root model is no longer a suitable basis for professional practice. We recommend that clinicians stop using sub-talar neutral position during clinical assessments and stop assessing the non-weight bearing range of ankle dorsiflexion, first ray position and forefoot alignments and movement as a means of defining the associated foot deformities. The results question the relevance of the Root assessments in the prescription of foot orthoses.

Clinical improvement in functional hallux limitus using a cut-out orthosis

BACKGROUND

Functional hallux limitus (FHL) has been implicated in the development of metatarsophalangeal joint osteoarthritis.

OBJECTIVES

To determine whether cut-out orthosis treatment increases plantarflexion of the first metatarsal by increasing its declination angle.

STUDY DESIGN

Cross-sectional study.

METHODS

A total of 46 female volunteers with an average age of 25.66 ± 5.70 years (range: 19-42 years) and FHL participated in the study. We assessed the degrees of movement of the first metatarsal and proximal phalanx bones at the first metatarsophalangeal joint without and while wearing the cut-out orthosis using the 3Space Fastrak® via sensors.

RESULTS

The movement of the plantarflexión declination angle of the first metatarsal bone was higher using the orthosis 29.84° ± 5.98° versus without orthosis 27.69° ± 5.91° (p < 0.031°). Use of sandals may have minimized the magnitude of movement changes associated with orthosis versus non-orthosis use.

CONCLUSION

The cut-out orthosis demonstrated a beneficial effect on non-fixed first metatarsophalangeal and metatarsal cuneiform joints affected by FHL, significantly increasing the declination of the metatarsal angle. Furthermore, use of the cut-out orthosis significantly reduced adduction movement of the first metatarsal bone in the transverse plane.

CLINICAL RELEVANCE

The cut-out orthosis demonstrated a beneficial effect on non-fixed first metatarsophalangeal and metatarsal cuneiform joints affected by FHL, significantly increasing the declination of the metatarsal angle. Furthermore, use of the cut-out orthosis significantly reduced adduction movement of the first metatarsal bone in the transverse plane.

Are Pressure Time Integral and Cumulative Plantar Stress Related to First Metatarsophalangeal Joint Pain? Results From a Community-Based Study

OBJECTIVE

To examine the relationship between plantar stress over a step, cumulative plantar stress over a day, and first metatarsophalangeal (MTP) joint pain among older adults.

METHODS

Plantar stress and first MTP pain were assessed within the Multicenter Osteoarthritis Study. All included participants were asked if they had pain, aching, or stiffness at the first MTP joint on most days for the past 30 days. Pressure time integral (PTI) was quantified as participants walked on a pedobarograph, and mean steps per day were obtained using an accelerometer. Cumulative plantar stress was calculated as the product of regional PTI and mean steps per day. Quintiles of hallucal and second metatarsal PTI and cumulative plantar stress were generated. The relationship between predictors and the odds ratio of first MTP pain was assessed using a logistic regression model.

RESULTS

Feet in the quintile with the lowest hallux PTI had 2.14 times increased odds of first MTP pain (95% confidence interval [95% CI] 1.42-3.25, P < 0.01). Feet in the quintile with the lowest second metatarsal PTI had 1.50 times increased odds of first MTP pain (95% CI 1.01-2.23, P = 0.042). Cumulative plantar stress was unassociated with first MTP pain.

CONCLUSION

Lower PTI was modestly associated with increased prevalence of frequent first MTP pain at both the hallux and second metatarsal. Lower plantar loading may indicate the presence of an antalgic gait strategy and may reflect an attempt at pain avoidance. The lack of association with cumulative plantar stress may suggest that patients do not limit their walking as a pain-avoidance mechanism.

Severity of pronation and classification of first metatarsophalangeal joint dorsiflexion increases the validity of the Hubscher Manoeuvre for the diagnosis of functional hallux limitus

BACKGROUND

Functional hallux limitus (FHL) is diagnosed with a static test known as the Hubscher Manoeuvre, the validity of which has been previously questioned.

OBJECTIVES

To investigate the validity of this Manoeuvre and whether introducing severity of pronation as a second concurrent test would increase this validity.

METHOD

30 participants with a hallux dorsiflexion <12° were divided into 2 equal groups, depending on their severity of pronation according to the Foot Posture Index. A single video camera, placed perpendicular to the plane of motion of the 1st MPJ, captured its movement, from which the angle of maximum dorsiflexion of this joint was measured.

RESULTS

10 males and 20 females, aged 18-56 years (mean 28 yrs, SD ± 12.1 yrs) participated. There was no significant relationship between non-weight bearing and dynamic maximum dorsiflexion (p=0.160), and between weight bearing and dynamic maximum dorsiflexion (p=0.865). A significant relationship between 1st MPJ dynamic maximum dorsiflexion and severity of pronation (p=0.004) was found.

CONCLUSIONS

None of the participants exhibited a complete lack of hallux dorsiflexion. A positive Hubscher Manoeuvre test, on its own, is not a good indicator of limited 1st MPJ dorsiflexion during dynamic motion. However, as pronation increases, 1st MPJ maximum dorsiflexion during gait decreases.

Plantar fasciitis and its relationship with hallux limitus

BACKGROUND

We sought to determine whether patients with plantar fasciitis have limited dorsiflexion in the first metatarsophalangeal joint and which type of foot, pronated or supinated, is most frequently associated with plantar fasciitis.

METHODS

The 100 study participants (34 men and 66 women) were divided into two groups: patients with plantar fasciitis and controls. The Foot Posture Index and dorsiflexion of the first metatarsophalangeal joint were compared between the two groups, and a correlation analysis was conducted to study their relationship.

RESULTS

In the plantar fasciitis group there was a slight limitation of dorsiflexion of the hallux that was not present in the control group (P < .001). Hallux dorsiflexion and the Foot Posture Index were inversely correlated (Spearman correlation coefficient, -0.441; P < .01).

CONCLUSIONS

Participants with plantar fasciitis presented less hallux dorsiflexion than those in the control group, and their most common foot type was the pronated foot.

Rocker-sole footwear versus prefabricated foot orthoses for the treatment of pain associated with first metatarsophalangeal joint osteoarthritis: study protocol for a randomised trial

BACKGROUND

Osteoarthritis affecting the first metatarsophalangeal joint of the foot is a common condition which results in pain, stiffness and impaired ambulation. Footwear modifications and foot orthoses are widely used in clinical practice to treat this condition, but their effectiveness has not been rigorously evaluated. This article describes the design of a randomised trial comparing the effectiveness of rocker-sole footwear and individualised prefabricated foot orthoses in reducing pain associated with first metatarsophalangeal joint osteoarthritis.

METHODS

Eighty people with first metatarsophalangeal joint osteoarthritis will be randomly allocated to receive either a pair of rocker-sole shoes (MBT® Matwa, Masai Barefoot Technology, Switzerland) or a pair of individualised, prefabricated foot orthoses (Vasyli Customs, Vasyli Medical™, Queensland, Australia). At baseline, the biomechanical effects of the interventions will be examined using a wireless wearable sensor motion analysis system (LEGSys™, BioSensics, Boston, MA, USA) and an in-shoe plantar pressure system (Pedar®, Novel GmbH, Munich, Germany). The primary outcome measure will be the pain subscale of the Foot Health Status Questionnaire (FHSQ), measured at baseline and 4, 8 and 12 weeks. Secondary outcome measures will include the function, footwear and general foot health subscales of the FHSQ, severity of pain and stiffness at the first metatarsophalangeal joint (measured using 100 mm visual analog scales), global change in symptoms (using a 15-point Likert scale), health status (using the Short-Form-12® Version 2.0 questionnaire), use of rescue medication and co-interventions to relieve pain, the frequency and type of self-reported adverse events and physical activity levels (using the Incidental and Planned Activity Questionnaire). Data will be analysed using the intention to treat principle.

DISCUSSION

This study is the first randomised trial to compare the effectiveness of rocker-sole footwear and individualised prefabricated foot orthoses in reducing pain associated with osteoarthritis of the first metatarsophalangeal joint, and only the third randomised trial ever conducted for this condition. The study has been pragmatically designed to ensure that the findings can be implemented into clinical practice if the interventions are found to be effective, and the baseline biomechanical analysis will provide useful insights into their mechanism of action.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12613001245785.

First metatarsophalangeal joint arthrodesis versus proximal phalanx hemiarthroplasty for hallux rigidus: feasibility study for a randomised controlled trial

Background

Osteoarthritis of the first metatarsophalangeal joint (hallux rigidus) leads to pain and poor function and mobility. Arthrodesis is the gold standard treatment for end-stage disease. Total joint arthroplasties have been attempted, but early loosening has been attributed to dorsally directed shear forces on the metatarsal component. Metallic proximal phalangeal hemiarthroplasty theoretically avoids this. Whilst early results are promising, no comparative trials exist comparing this to arthrodesis.

Methods/Design

The primary objectives are to determine the range of outcome scores between the two treatment arms (to inform a power calculation). Outcome measures will include the MOXFQ, AOFAS-Hallux and EuroQol EQ-5D-5 L. Secondary objectives are to determine the accrual rate, dropout rate and trial acceptability to both patients and surgeons. These data will allow the development of a larger trial with longer follow-up.

This is a prospective randomised controlled single-centre study comparing proximal phalanx hemiarthroplasty (AnaToemic, Arthrex Ltd., Sheffield, UK) with arthrodesis (15 patients in each arm). Randomisation will be performed using a 1:1 allocation ratio in blocks of six.

Patients meeting the eligibility criteria will be recruited from three foot and ankle consultant surgeon’s clinics (East Lancashire Hospitals NHS Trust). If agreeable, informed consent will be obtained before patients are randomised.

The outcome measure scores will be completed pre-operatively and repeated at 6 weeks, 3 months and 12 months. A radiological review will be performed at 6 weeks and 12 months to determine rates of loosening (hemiarthroplasty) and union (arthrodesis). Data on length of stay, return to work, complications and re-operation rates will also be collected.

The analysis will compare the change in outcome scores between treatment groups at all follow-up time points. Scores will be compared using a Student t-test, adjusting for scores at baseline.

This study will be conducted in accordance with the current revision of the Declaration of Helsinki (1996) and the ICH-GCP Guideline (International Conference on Harmonisation, Good Clinical Practice, E6(R1), 1996). This study has been approved by the sponsor, the Trust Research & Development office. Ethical approval has been received from the National Research Ethics Service (North East: 12/NE/0385 for protocol version 5.3 dated 3 June 2013).

Trial registration

Current Controlled Trials ISRCTN88273654

Classification of forefoot plantar pressure distribution in persons with diabetes: a novel perspective for the mechanical management of diabetic foot?

Background

The aim of this study was to identify groups of subjects with similar patterns of forefoot loading and verify if specific groups of patients with diabetes could be isolated from non-diabetics.

Methodology/Principal Findings

Ninety-seven patients with diabetes and 33 control participants between 45 and 70 years were prospectively recruited in two Belgian Diabetic Foot Clinics. Barefoot plantar pressure measurements were recorded and subsequently analysed using a semi-automatic total mapping technique. Kmeans cluster analysis was applied on relative regional impulses of six forefoot segments in order to pursue a classification for the control group separately, the diabetic group separately and both groups together. Cluster analysis led to identification of three distinct groups when considering only the control group. For the diabetic group, and the computation considering both groups together, four distinct groups were isolated. Compared to the cluster analysis of the control group an additional forefoot loading pattern was identified. This group comprised diabetic feet only. The relevance of the reported clusters was supported by ANOVA statistics indicating significant differences between different regions of interest and different clusters.

Conclusion/s Significance

There seems to emerge a new era in diabetic foot medicine which embraces the classification of diabetic patients according to their biomechanical profile. Classification of the plantar pressure distribution has the potential to provide a means to determine mechanical interventions for the prevention and/or treatment of the diabetic foot.

Pattern description and reliability parameters of six force-time related indices measured with plantar pressure measurements

BACKGROUND

Functional interpretation of plantar pressure measurements is commonly done through the use of ratios and indices which are preceded by the strategic combination of a subsampling method and selection of physical quantities. However, errors which may arise throughout the determination of these temporal indices/ratio calculations (T-IRC) have not been quantified. The purpose of the current study was therefore to estimate the reliability of T-IRC following semi-automatic total mapping (SATM).

METHODS

Using a repeated-measures design, two experienced therapists performed three subsampling sessions on three left and right pedobarographic footprints of ten healthy participants. Following the subsampling, six T-IRC were calculated: Rearfoot-Forefoot_fti, Rearfoot-Midfoot_fti, Forefoot medial/lateral_fti, First ray_fti, Metatarsal 1-Metatarsal 5_fti, Foot medial-lateral_fti.

FINDINGS

Patterns of the T-IRC were found to be consistent and in good agreement with corresponding knowledge from the literature. The inter-session errors of both therapists were similar in pattern and magnitude. The lowest peak inter-therapist error was found in the First ray_fti (6.5 a.u.) whereas the highest peak inter-therapist error was observed in the Forefoot medial/lateral_fti (27.0 a.u.) The magnitude of the inter-session and inter-therapist error varied over time, precluding the calculation of a simple numerical value for the error. The difference between both error parameters of all T-IRC was negligible which underscores the repeatability of the SATM protocol.

CONCLUSION

The current study reports consistent patterns for six T-IRC and similar inter-session and inter-therapist error. The proposed SATM protocol and the T-IRC may therefore serve as basis for functional interpretation of footprint data.

Hallux interphalangeal joint range of motion in feet with and without limited first metatarsophalangeal joint dorsiflexion

BACKGROUND

This work was designed to assess the degree of correlation between hallux interphalangeal joint and first metatarsophalangeal joint dorsiflexion and to compare the mobility of the hallux interphalangeal joint between participants with and without limited first metatarsophalangeal joint dorsiflexion (hallux limitus).

METHODS

Dorsiflexion of the hallux interphalangeal joint was measured in 60 normal feet and in 60 feet with hallux limitus to find correlations with first metatarsophalangeal joint dorsiflexion with the Spearman correlation coefficient and a simple linear regression equation. In addition, movement of the hallux interphalangeal joint was compared between normal and hallux limitus feet with the Mann-Whitney U test.

RESULTS

Significant differences were found between the groups in mean ± SD interphalangeal joint dorsiflexion (control group: 1.17° ± 2.50° ; hallux limitus group: 10.65° ± 8.24° ; P < .001). A significant inverse correlation was found between first metatarsophalangeal joint dorsiflexion and hallux interphalangeal joint dorsiflexion (ρ = -0.766, P < .001), and the regression equation from which predictions could be made is the following: hallux interphalangeal joint dorsiflexion = 27.17 - 0.381 × first metatarsophalangeal joint dorsiflexion.

CONCLUSIONS

Hallux interphalangeal joint dorsiflexion was greater in feet with hallux limitus than in normal feet. There was a strong inverse correlation between first metatarsophalangeal joint dorsiflexion and hallux interphalangeal joint dorsiflexion.

Nineteen-year follow-up of the silastic double stemmed hinge prosthesis of the first metatarsophalangeal joint

BACKGROUND

The purpose of this retrospective study is to evaluate patient-related outcome and reoperation rate of the Swanson prosthesis in patients with and without grommets.

METHODS

Between 1981 and 1999, 98 Swanson MTP-1 prostheses were implanted in 84 patients (14 bilateral). The average follow-up was 19 years. Patients were asked to fill in the Foot and Ankle Outcome Score (FAOS) questionnaire and were asked if they had undergone reoperations. In addition, medical records where searched.

RESULTS

36 patients (mean age 71 years) returned the questionnaire. All median FAOS sub scores were 100. There were no differences in FAOS sub scores between patients who had a prosthesis with or without grommets, except for FAOS "activities in daily living" which was lower for patients without grommets. Reoperation rate was 4%.

CONCLUSION

The Swanson silastic double stemmed hinge prosthesis showed good to excellent patient-related outcome and reoperation rate at long-term follow-up.

Hállux Rígidus: prospective study of joint replacement with hemiarthroplasty

OBJECTIVE:

To report the results of medium-term follow-up after deploying Arthrosurface-HemiCap^(r) in patients with diagnosis of Hállux Rigidus (HR).

METHOD:

Eleven patients underwent partial Arthroplasty of the first metatarsal-phalangeal joint. Six women and five men with an average age 51.9 years (46 to 58 years) and average postoperative follow-up of 3.73 years (3-4 years); were classified through the Kravitz system and evaluated by the American Orthopaedic Foot and Ankle Society (AOFAS) scales for hállux, Visual Analogical Scale (VAS) - analog functional pain - and range of motion in the first metatarsal joint in preoperative, postoperative after six months and present post-operative.

RESULTS:

The results show significant improvement of the three analyzed parameters, both for overall analysis and for pre and post-operative comparisons individually. The comparative analysis of each variable in the six months and the current postoperative periods do not show statistically significant differences, indicating maintenance of parameters during this interval.

CONCLUSION:

hemiarthroplasty of first metatarsophalangeal joint is a reproducible and safe option for the surgical treatment of hállux rigidus II and III, with significant improvement of the evaluated parameters for the studied population. Level of Evidence IV, Case Series.

Clustering and classification of regional peak plantar pressures of diabetic feet

High plantar pressures have been associated with foot ulceration in people with diabetes, who can experience loss of protective sensation due to peripheral neuropathy. Therefore, characterization of elevated plantar pressure distributions can provide a means of identifying diabetic patients at potential risk of foot ulceration. Plantar pressure distribution classification can also be used to determine suitable preventive interventions, such as the provision of an appropriately designed insole. In the past, emphasis has primarily been placed on the identification of individual focal areas of elevated pressure. The goal of this study was to utilize k-means clustering analysis to identify typical regional peak plantar pressure distributions in a group of 819 diabetic feet. The number of clusters was varied from 2 to 10 to examine the effect on the differentiation and classification of regional peak plantar pressure distributions. As the number of groups increased, so too did the specificity of their pressure distributions: starting with overall low or overall high peak pressure groups and extending to clusters exhibiting several focal peak pressures in different regions of the foot. However, as the number of clusters increased, the ability to accurately classify a given regional peak plantar pressure distribution decreased. The balance between these opposing constraints can be adjusted when assessing patients with feet that are potentially "at risk" or while prescribing footwear to reduce high regional pressures. This analysis provides an understanding of the variability of the regional peak plantar pressure distributions seen within the diabetic population and serves as a guide for the preemptive assessment and prevention of diabetic foot ulcers.

Association of hypermobility and ingrown nails

Ingrown nail (onychocryptosis) is a common condition with severe pain and various associated morbidities. Although some underlying factors are identified, its etiology remains largely unknown. Generalized joint hypermobility (GJH) is a common entity with clinical features that might prone affected individuals to ingrown nails. Herein, we investigated the incidence of GJH in patients with ingrown nails to determine possible association between hypermobility and ingrown nail formation. Patients 16-50 years of age who were undergoing treatment for ingrown nails at the dermatology clinic were consecutively enrolled into the study. Patients with known rheumatic diseases or orthopedic foot disorders were excluded. All patients were in a pain-free period at the time of examination. The control group was comprised of age- and sex-matched healthy subjects without a history of ingrown nail. Assessment of GJH was made according to Beighton criteria. Local hypermobility was evaluated by measurement of range of motion using a goniometer. Thirty-nine patients (male/female, 17/22, mean age 31.9 ± 11.3 years) and 32 healthy subjects (male/female 12/20, mean age 31.7 ± 10.4 years) were included. Patients with ingrown toe nails were more likely to have GJH compared to healthy subjects (35.9 vs. 9.4 %, p = 0.009). Toes with ingrown nails had significantly smaller maximum dorsiflexion angles (p < 0.001) compared to toes of healthy subjects. Ingrown nail formation may be associated with GJH. However, when examined locally, there is a limited range of motion in the affected toe rather than hypermobility, which could be due to the degenerative process facilitated by the hypermobility.

Proximal and distal contributions to lower extremity injury: a review of the literature

Excessive or prolonged foot pronation has been linked to the development of numerous overuse injuries affecting the lower limb. The originally proposed pathomechanical model suggests foot motion affects more proximal structures through disruption of distal to proximal coupling between the foot, tibia, femur, and hip. Research evidence supports the presence of a dynamic coupling mechanism between lower limb segments, however, the direction of the coupling is inconclusive. Recent prospective investigations of the role of the lumbo-pelvic hip complex have identified a strong association between proximal dysfunction and increased risk of lower limb injuries. Strength of muscles of the lumbo-pelvic hip complex (core muscles) is suggested to be essential to controlling hip abduction, subsequent internal rotation of the femur and potentially more distal movement. Proximal muscle weakness and altered motor control have also been implicated in the development of numerous lower limb injuries, many of which have previously been attributed to excessive foot pronation. This review discusses the theoretical basis for the role of proximal and distal structures in biomechanical dysfunction of the lower limb and the development of lower limb overuse injury. Current prospective evidence relating to the contributions of excessive foot pronation and core muscle function to the development of lower extremity injury is evaluated.

The pathogenesis of hallux valgus

The first ray is an inherently unstable axial array that relies on a fine balance between its static (capsule, ligaments, and plantar fascia) and dynamic stabilizers (peroneus longus and small muscles of the foot) to maintain its alignment. In some feet, there is a genetic predisposition for a nonlinear osseous alignment or a laxity of the static stabilizers that disrupts this muscle balance. Poor footwear plays an important role in accelerating the process, but occupation and excessive walking and weight-bearing are unlikely to be notable factors. Many inherent or acquired biomechanical abnormalities are identified in feet with hallux valgus. However, these associations are incomplete and nonlinear. In any patient, a number of factors have come together to cause the hallux valgus. Once this complex pathogenesis is unraveled, a more scientific approach to hallux valgus management will be possible, thereby enabling treatment (conservative or surgical) to be tailored to the individual.

Is barefoot regional plantar loading related to self-reported foot pain in patients with midfoot osteoarthritis

OBJECTIVE

While recent evidence suggests that foot pain may be related to mechanical stress, quantitative data elucidating the role of regional plantar loading in foot pain in individuals with midfoot osteoarthritis (OA) are lacking. Therefore the authors' objective is to examine regional plantar loading and self-reported foot pain in patients with midfoot OA compared to asymptomatic, matched control subjects.

METHOD

Fifty subjects, 30 patients with midfoot OA and 20 control subjects participated in this study. Self-reported function was assessed using the Foot Function Index-Revised (FFI-R). Plantar loading during barefoot walking at self-selected, monitored walking speed was quantified using an EMED pedobarograph. Between-group differences in FFI-R score and plantar loading were assessed using an independent t-test and the Mann-Whitney U-test respectively. The relationship between FFI-R score and plantar loading was assessed using Spearman rank correlation. A k-means cluster analysis was used to identify potential sub-groups of patients through regional plantar loading.

RESULTS

The key findings of this study showed that patients with midfoot OA reported significantly higher FFI-R scores, and higher heel and medial midfoot average pressure compared to control subjects. Medial midfoot pressure-time integral was positively associated with FFI-R Pain Subscale Score (r=0.524, P<0.01). Based on the adequacy index, the two-cluster solution was deemed most appropriate.

CONCLUSION

This study demonstrated that patients with midfoot OA sustain increased magnitude and duration of regional plantar loading during walking compared to matched control subjects. Our findings support the theory that regional mechanical stress may be associated with symptoms in patients with midfoot OA. Future studies should assess whether interventions designed to reduce plantar loading are effective in relieving foot pain, and preventing progression of symptoms in patients with midfoot OA.

The effect of foot structure on 1st metatarsophalangeal joint flexibility and hallucal loading

The purpose of our study was to examine 1st metatarsophalangeal (MTP) joint motion and flexibility and plantar loads in individuals with high, normal and low arch foot structures. Asymptomatic individuals (n=61), with high, normal and low arches participated in this study. Foot structure was quantified using malleolar valgus index (MVI) and arch height index (AHI). First MTP joint flexibility was measured using a specially constructed jig. Peak pressure under the hallux, 1st and 2nd metatarsals during walking was assessed using a pedobarograph. A one-way ANOVA with Bonferroni-adjusted post hoc comparisons was used to assess between-group differences in MVI, AHI, early and late 1st MTP joint flexibility in sitting and standing, peak dorsiflexion (DF), and peak pressure under the hallux, 1st and 2nd metatarsals. Stepwise linear regression was used to identify predictors of hallucal loading. Significant between-group differences were found in MVI (F(2,56)=15.4, p<0.01), 1st MTP late flexibility in sitting (F(2,57)=3.7, p=0.03), and standing (F(2,57)=3.7, p=0.03). Post hoc comparisons demonstrated that 1st MTP late flexibility in sitting was significantly higher in individuals with low arch compared to high arch structure, and that 1st MTP late flexibility in standing was significantly higher in individuals with low arch compared to normal arch structure. Stepwise regression analysis indicated that MVI and 1st MTP joint early flexibility in sitting explain about 20% of the variance in hallucal peak pressure. Our results provide objective evidence indicating that individuals with low arches show increased 1st MTP joint late flexibility compared to individuals with normal arch structure, and that hindfoot alignment and 1st MTP joint flexibility affect hallucal loading.

Body of evidence supporting the clinical use of 3D multisegment foot models: a systematic review

BACKGROUND

A critical component in the characterization of foot mechanics during clinical gait analysis is the quantitative measurement of foot kinematics. Currently, the use of 3D multisegment foot models (3DMFMs) is popular in gait laboratories as it would seem to be an adequate tool for the in vivo analysis of dynamic foot kinematics. This systematic review identifies and evaluates current evidence for the use of 3DMFMs in clinical gait analysis.

METHODS

A targeted search strategy traced full papers that fulfilled the inclusion and exclusion criteria. The papers were classified and evaluated for quality using a custom made quality appraisal form.

FINDINGS

Forty-one manuscripts were included yielding a total number of fifteen 3DMFMs. Generally, study procedures and sample selection were adequately described; however, the methodological quality varied widely. Evidence regarding the repeatability of the identified models also varied widely. Models facing the highest level of scientific credibility were characterized by adequate repeatability indices obtained from between-trial, between-day and between and within assessor studies. Generally, the highest reliability indices were found for the sagittal plane kinematics. Within-subject variability was found to be the lowest, contrarily, between-subject and between-day variabilities were found to be highest.

INTERPRETATION

Reported repeatability indices such as the coefficient of multiple correlation, standard deviation and standard error of measurement provide evidence for the continued use of 3DMFMs. While a number of published models exist, there is no adequate evidence available to support their clinical use. More reliability and validity studies are needed to confirm adequate measurement properties of 3DMFMs.

Foot kinematics in patients with two patterns of pathological plantar hyperkeratosis

Background

The Root paradigm of foot function continues to underpin the majority of clinical foot biomechanics practice and foot orthotic therapy. There are great number of assumptions in this popular paradigm, most of which have not been thoroughly tested. One component supposes that patterns of plantar pressure and associated hyperkeratosis lesions should be associated with distinct rearfoot, mid foot, first metatarsal and hallux kinematic patterns. Our aim was to investigate the extent to which this was true.

Methods

Twenty-seven subjects with planter pathological hyperkeratosis were recruited into one of two groups. Group 1 displayed pathological plantar hyperkeratosis only under metatarsal heads 2, 3 and 4 (n = 14). Group 2 displayed pathological plantar hyperkeratosis only under the 1^st and 5^th metatarsal heads (n = 13). Foot kinematics were measured using reflective markers on the leg, heel, midfoot, first metatarsal and hallux.

Results

The kinematic data failed to identify distinct differences between these two groups of subjects, however there were several subtle (generally <3°) differences in kinematic data between these groups. Group 1 displayed a less everted heel, a less abducted heel and a more plantarflexed heel compared to group 2, which is contrary to the Root paradigm.

Conclusions

There was some evidence of small differences between planter pathological hyperkeratosis groups. Nevertheless, there was too much similarity between the kinematic data displayed in each group to classify them as distinct foot types as the current clinical paradigm proposes.

A case-series study to explore the efficacy of foot orthoses in treating first metatarsophalangeal joint pain

Background

First metatarsophalangeal (MTP) joint pain is a common foot complaint which is often considered to be a consequence of altered mechanics. Foot orthoses are often prescribed to reduce 1^st MTP joint pain with the aim of altering dorsiflexion at propulsion. This study explores changes in 1^st MTP joint pain and kinematics following the use of foot orthoses.

Methods

The effect of modified, pre-fabricated foot orthoses (X-line^®) were evaluated in thirty-two patients with 1^st MTP joint pain of mechanical origin. The primary outcome was pain measured at baseline and 24 weeks using the pain subscale of the foot function index (FFI). In a small sub-group of patients (n = 9), the relationship between pain and kinematic variables was explored with and without their orthoses, using an electromagnetic motion tracking (EMT) system.

Results

A significant reduction in pain was observed between baseline (median = 48 mm) and the 24 week endpoint (median = 14.50 mm, z = -4.88, p < 0.001). In the sub-group analysis, we found no relationship between pain reduction and 1^st MTP joint motion, and no significant differences were found between the 1^st MTP joint maximum dorsiflexion or ankle/subtalar complex maximum eversion, with and without the orthoses.

Conclusions

This observational study demonstrated a significant decrease in 1^st MTP joint pain associated with the use of foot orthoses. Change in pain was not shown to be associated with 1^st MTP joint dorsiflexion nor with altered ankle/subtalar complex eversion. Further research into the effect of foot orthoses on foot function is indicated.

Inter- and intra-observer reliability of masking in plantar pressure measurement analysis

Plantar pressure measurement is an important tool in gait analysis. Manual placement of small masks (masking) is increasingly used to calculate plantar pressure characteristics. Little is known concerning the reliability of manual masking. The aim of this study was to determine the reliability of masking on 2D plantar pressure footprints, in a population with forefoot deformity (i.e. hallux valgus). Using a random repeated-measure design, four observers identified the third metatarsal head on a peak-pressure barefoot footprint, using a small mask. Subsequently, the location of all five metatarsal heads was identified, using the same size of masks and the same protocol. The 2D positional variation of the masks and the peak pressure (PP) and pressure time integral (PTI) values of each mask were calculated. For single-masking the lowest inter-observer reliability was found for the distal-proximal direction, causing a clear, adverse impact on the reliability of the pressure characteristics (PP and PTI). In the medial-lateral direction the inter-observer reliability could be scored as high. Intra-observer reliability was better and could be scored as high or good for both directions, with a correlated improved reliability of the pressure characteristics. Reliability of multi-masking showed a similar pattern, but overall values tended to be lower. Therefore, small sized masking in order to define pressure characteristics in the forefoot should be done with care.

Effect of turf toe on foot contact pressures in professional American football players

BACKGROUND

The relationship between turf toe and plantar foot pressures has not been extensively studied. Two hypotheses were tested in a cohort of professional American football players: first, that a history of turf toe is associated with increased peak hallucal and first metatarsophalangeal (MTP) plantar pressures; second, that decreased range of motion (ROM) of the first MTP correlates with increased peak hallucal and first MTP plantar pressures.

MATERIALS AND METHODS

Forty-four athletes from one National Football League (NFL) team were screened for a history of turf toe during preseason training. Dorsal passive MTP ROM and dynamic plantar pressures were measured in both feet of each player. Anatomical masking was used to assess peak pressure at the first MTP and hallux.

RESULTS

First MTP dorsiflexion was significantly lower in halluces with a history of turf toe (40.6 +/- 15.1 degrees versus 48.4 +/- 12.8 degrees, p = 0.04). Peak hallucal pressures were higher in athletes with turf toe (535 +/- 288 kPa versus 414 +/- 202 kPa, p = 0.05) even after normalizing for athlete body mass index (p = 0.0003). Peak MTP pressure was not significantly different between the two groups tested. First MTP dorsiflexion did not correlate with peak hallucal or first MTP pressures.

CONCLUSION

This study showed that turf toe is associated with decreased MTP motion. In addition, increased peak hallucal pressures were found. Further study is warranted to determine whether these pressures correlate with the severity of symptoms or progression of turf toe to first MTP arthritis.

Hallux rigidus: MTP implant arthroplasty

Hallux rigidus or osteoarthritis of the first metatarsophalangeal joint is characterized by pain, stiffness of the joint, and alterations of gait. The appeal of joint arthroplasty for hallux rigidus is similar to its benefits in other joints in the body. The ideal implant should relieve pain, restore motion, improve function, and maintain joint stability. Numerous implants have been described for the hallux metatarsophalangeal joint. This article discusses various implant options along with clinical outcomes and complications.

Prediction of peak pressure from clinical and radiological measurements in patients with diabetes

BACKGROUND

Various structural and functional factors of foot function have been associated with high local plantar pressures. The therapist focuses on these features which are thought to be responsible for plantar ulceration in patients with diabetes. Risk assessment of the diabetic foot would be made easier if locally elevated plantar pressure could be indicated with a minimum set of clinical measures.

METHODS

Ninety three patients were evaluated through vascular, orthopaedic, neurological and radiological assessment. A pressure platform was used to quantify the barefoot peak pressure for six forefoot regions: big toe (BT) and metatarsals one (MT-1) to five (MT-5). Stepwise regression modelling was performed to determine which set of the clinical and radiological measures explained most variability in local barefoot plantar peak pressure in each of the six forefoot regions. Comprehensive models were computed with independent variables from the clinical and radiological measurements. The difference between the actual plantar pressure and the predicted value was examined through Bland-Altman analysis.

RESULTS

Forefoot pressures were significant higher in patients with neuropathy, compared to patients without neuropathy for the whole forefoot, the MT-1 region and the MT-5 region (respectively 138 kPa, 173 kPa and 88 kPa higher: mean difference). The clinical models explained up to 39 percent of the variance in local peak pressures. Callus formation and toe deformity were identified as relevant clinical predictors for all forefoot regions. Regression models with radiological variables explained about 26 percent of the variance in local peak pressures. For most regions the combination of clinical and radiological variables resulted in a higher explained variance. The Bland and Altman analysis showed a major discrepancy between the predicted and the actual peak pressure values.

CONCLUSION

At best, clinical and radiological measurements could only explain about 34 percent of the variance in local barefoot peak pressure in this population of diabetic patients. The prediction models constructed with linear regression are not useful in clinical practice because of considerable underestimation of high plantar pressure values. Identification of elevated plantar pressure without equipment for quantification of plantar pressure is inadequate. The use of quantitative plantar pressure measurement for diabetic foot screening is therefore advocated.

Plantar pressure distribution in older people with osteoarthritis of the first metatarsophalangeal joint (hallux limitus/rigidus)

The purpose of this study was to evaluate differences in dynamic plantar pressure distribution between older people with and without radiographically confirmed osteoarthritis (OA) of the first metatarsophalangeal joint (first MPJ) of the foot. Dynamic plantar pressure recordings using the TekScan MatScan system were obtained during barefoot level walking in 40 older participants; 20 with radiographically confirmed OA of the first MPJ displaying less than 55 degrees of passive dorsiflexion, and 20 with no evidence of OA in the first MPJ displaying greater than 55 degrees of passive dorsiflexion. Group comparisons between the variables maximum force and peak pressure were made for seven different regions underneath the right foot (heel, midfoot, first MPJ, second MPJ, third to fifth MPJs, hallux, and lesser toes). Compared to the control group, participants with OA of the first MPJ exhibited 34% greater maximum force (7.9 +/- 2.5 vs. 5.9 +/- 1.7 kg, p = 0.005) and 23% higher peak pressure (1.6 +/- 0.3 vs. 1.3 +/- 0.3 kg/cm(2), p = 0.001) under the hallux. Similar results were also found under the lesser toes with 43% greater maximum force (5.0 +/- 1.9 vs. 3.5 +/- 1.4 kg; p = 0.006) and 29% higher peak pressure (0.9 +/- 0.2 vs. 0.7 +/- 0.2 kg/cm(2), p = 0.018). No significant differences were found to exist between groups for any other plantar region. These findings indicate that OA of the first MPJ is associated with significant changes in load-bearing function of the foot, which may contribute to the development of secondary pathological changes associated with the condition, such as plantar callus formation and hyperextension of the hallux interphalangeal joint.

Dynamic kinematic and plantar pressure changes following cheilectomy for hallux rigidus: a mid-term followup

BACKGROUND

Hallux rigidus leads to significant loss of first metatarsophalangeal (MTP) joint motion. Cheilectomy surgery aims to increase motion, decrease pain, and facilitate a return to activity. Limited data exist regarding restoration of dynamic kinematics and loading responses following cheilectomy. This prospective study assessed three-dimensional in vivo first MTP joint kinematics and loading characteristics following cheilectomy.

MATERIALS AND METHODS

Twenty patients were evaluated prior to undergoing cheilectomy for hallux rigidus. Fifteen subjects returned for mid-term followup at 1.7 years. Eleven subjects were surveyed at 6 years. Plantar pressure data were acquired during barefoot walking. Comparisons of average pressures were determined for 4 different regions of the foot. Pressure differences were compared within, and between symptomatic and asymptomatic feet. First MTP joint dorsiflexion and abduction were assessed during standing, active motion and gait.

RESULTS

Only four out of 15 patients showed increased lateral metatarsal loading preoperatively. Pressures shifted medially following surgery. Significant increases in dorsiflexion were found for active motion (pre-op = 13.3 +/- 12.7 degrees; post-op = 21.7 +/- 14.7 degrees, p = 0.005) and dorsiflexion during gait (pre-op = 19.3 +/- 12 degrees; post-op = 30.8 +/- 14.8 degrees, p = 0.01). Hallux abduction also increased. During standing, the hallux remained in plantarflexion relative to the first metatarsal.

CONCLUSION

Cheilectomy was effective in maintaining balanced plantar loading. First MTP motion increased but dorsiflexion was still less than normative values. The magnitude of dorsiflexion relative to abduction favorably improved during gait. These findings suggest that kinematics continue to be altered and may lead to further degenerative joint changes. Exploration of alternative surgical techniques is warranted.