Compensatory Midfoot Dorsiflexion in the Individual with Heelcord Tightness: Implications for Orthotic Device Designs:

Effects of foot and ankle mobilisations combined with home stretches in people with diabetic peripheral neuropathy: a proof-of-concept RCT

INTRODUCTION

People with diabetic peripheral neuropathy (DPN) and limited joint mobility syndrome (LJMS) can experience increased forefoot peak plantar pressures (PPPs), a known risk factor for ulceration. The aim of this study was to investigate whether ankle and 1st metatarsophalangeal (MTP) joint mobilisations and home-based stretches in people with DPN improve joint range of motion (ROM) and reduce forefoot PPPs.

DESIGN AND METHODS

Sixty-one people with DPN (IWGDF risk 2), were randomly assigned to a 6-week programme of ankle and 1st MTP joint mobilisations (n = 31) and home-based stretches or standard care only (n = 30). At baseline (T0); 6-week post intervention (T1) and at 3 months follow-up (T2), a blinded assessor recorded dynamic ankle dorsiflexion range using 3D (Codamotion) motion analysis and the weight bearing lunge test, static 1st MTP joint dorsiflexion ROM, dynamic plantar pressure and balance.

RESULTS

At T1 and T2 there was no difference between both groups in ankle dorsiflexion in stance phase, plantar pressure and balance. Compared to the control group, the intervention group showed a statistically significant increase in static ankle dorsiflexion range (Left 1.52 cm and 2.9cms, Right 1.62 cm and 2.7 cm) at 6 (T1) and 18 weeks (T2) respectively p < 0.01). Between group differences were also seen in left hallux dorsiflexion (2.75°, p < 0.05) at T1 and in right hallux dorsiflexion ROM (4.9°, p < 0.01) at T2 follow up. Further, functional reach showed a significant increase in the intervention group (T1 = 3.13 cm p < 0.05 and T2 = 3.9 cm p < 0.01). Intervention adherence was high (80%).

CONCLUSIONS

Combining ankle and 1st MTP joint mobilisations with home-based stretches in a 6-week programme in people with DPN is effective in increasing static measures of range. This intervention may be useful for improving ankle, hallux joint mobility and anteroposterior stability limits in people with diabetes and neuropathy but not for reducing PPP or foot ulcer risk.

TRIAL REGISTRATION

https://classic.

CLINICALTRIALS

gov/ct2/show/NCT03195855 .

Spatial-temporal parameters, pelvic and lower limb movements during gait in individuals with reduced passive ankle dorsiflexion

BACKGROUND

Proper ankle dorsiflexion range of motion (ADF-ROM) allows the anterior roll of the tibia relative to the foot during the midstance phase of gait, which contributes to forward movement of the body. Individuals with reduced passive ADF-ROM may present altered movement patterns during gait due to an inefficient anterior tibial roll over the support foot during the stance phase.

RESEARCH QUESTION

What is the influence of reduced passive ADF-ROM on the pelvic and lower limb movements and spatiotemporal parameters during gait?

METHOD

Thirty-two participants divided into two groups according to the degree of passive ADF-ROM-less than 10° (lower ADF-ROM group) or greater than 15° (higher ADF-ROM group) -were subjected to gait assessment using a three-dimensional motion analysis system. Independent t-tests were used to compare the pelvic and lower limb movements and spatiotemporal gait parameters between the groups on this cross-sectional study.

RESULTS

The lower ADF-ROM group had shorter step length, lower peak of pelvic ipsilateral rotation angle, and lower hip and knee maximum flexion angles in the stance phase (p < 0.05). In addition, the peaks of the ankle and forefoot-rearfoot dorsiflexion angles were smaller in the reduced ADF-ROM group (p < 0.05). The between-group differences presented effect sizes varying from moderate to large.

SIGNIFICANCE

Individuals with reduced passive ADF-ROM presented reduced foot and ankle dorsiflexion, knee and hip flexion, and pelvis rotation movements and shorter step length during gait. However, no differences in foot pronation were noted between groups. Therefore, individuals with reduced passive ADF-ROM present alterations in the lower limb and pelvic movements during gait.

Effects of Walking With Talus-Stabilizing Taping on Passive Range of Motion, Timed Up and Go, Temporal Parameters of Gait, and Fall Risk in Individuals With Chronic Stroke: A Cross-sectional Study

OBJECTIVE

The purpose of this study was to determine the effects of walking with talus-stabilizing taping on ankle dorsiflexion passive range of motion, the timed up-and-go test, temporal parameters of gait, and fall risk in individuals with chronic stroke.

METHODS

In this cross-sectional design study, 20 participants with chronic stroke (9 female, 11 male), aged 60.5 ± 8.1 years, were included. Three conditions were evaluated: barefoot, immediately after applying talus-stabilizing taping, and after 5 minutes of walking with talus-stabilizing taping. One-way repeated-measures analysis of variance was used to determine the differences in ankle dorsiflexion passive range of motion, timed up-and-go test results, temporal parameters of gait, and fall risk across the 3 conditions.

RESULTS

Ankle dorsiflexion passive range of motion, walking speed, and single-limb support phase were significantly improved after 5 minutes of walking with talus-stabilizing taping compared to those in the barefoot and immediately-after-taping conditions. The timed up-and-go test, double-limb support phase, and fall-risk results significantly decreased more after 5 minutes of walking with talus-stabilizing taping compared to barefoot and immediately after taping.

CONCLUSION

After the application of talus-stabilizing taping, ankle dorsiflexion passive range of motion, timed up-and-go test results, temporal parameters of gait, and fall risk were reduced in individuals with chronic stroke.

Role of mechanical factors in the clinical presentation of plantar heel pain: Implications for management

Plantar heel pain is a common musculoskeletal foot disorder that can have a negative impact on activities of daily living and it is of multifactorial etiology. A variety of mechanical factors, which result in excessive load at the plantar fascia insertion, are thought to contribute to the onset of the condition. This review presents the evidence for associations between commonly assessed mechanical factors and plantar heel pain, which could guide management. Plantar heel pain is associated with a higher BMI in non-athletic groups, reduced dorsiflexion range of motion, as well as reduced strength in specific foot and ankle muscle groups. There is conflicting, or insufficient evidence regarding the importance of foot alignment and first metatarsophalangeal joint range of motion. Plantar heel pain appears to be common in runners, with limited evidence for greater risk being associated with higher mileage or previous injuries. Conflicting evidence exists regarding the relationship between work-related standing and plantar heel pain, however, longer standing duration may be associated with plantar heel pain in specific worker groups. The evidence presented has been generated through studies with cross-sectional designs, therefore it is not known whether any of these associated factors have a causative relationship with plantar heel pain. Longitudinal studies are needed to ascertain whether the strength and flexibility impairments associated with plantar heel pain are a cause or consequence of the condition, as well as to establish activity thresholds that increase risk. Intervention approaches should consider strategies that improve strength and flexibility, as well as those that influence plantar fascia loading such as body weight reduction, orthoses and management of athletic and occupational workload.

Effects of solid ankle-foot orthoses with individualized ankle angles on gait for children with cerebral palsy and equinus

PURPOSE

For children with cerebral palsy (CP) and equinus, the conventional practice of setting the ankle angle in an ankle-foot orthosis (AA-AFO) at 90∘ may not adequately accommodate gastrocnemius length/stiffness. Therefore, this study compared the effects of statically-optimized solid AFOs with individualized AA-AFOs (iAA-AFOs) and conventionally-prescribed AFOs on gait for children with CP and equinus.

METHODS

Ten children with CP and equinus (15 limbs with AFOs), and 15 typically-developing (TD) children participated. For the children with CP, solid AFOs with iAA-AFOs (range = 5∘-25∘ plantarflexion) were compared with their usual AFOs using three-dimensional gait analysis. TD children walked in shoes only. Peak values and Gait Variable Scores (GVS) for joint and segment variables were calculated for stance phase. Responses were categorized using 90% confidence intervals relative to TD data, for each affected leg.

RESULTS

Net responses to iAA-AFOs were positive for 60% of limbs and negative for 40%. Knee variables (GVS and peak extension, flexion, and midstance moment) were most positively affected, and foot-floor angle and vertical ground reaction force were most negatively impacted.

CONCLUSION

Individualized AFO prescription and iAA-AFOs can impact gait biomechanics for some children with equinus, compared to conventionally-prescribed AFOs. Optimizing dynamic alignment for walking may further improve outcomes.

How Much Does the Talocrural Joint Contribute to Ankle Dorsiflexion Range of Motion During the Weight-Bearing Lunge Test? A Cross-sectional Radiographic Validity Study

BACKGROUND

Ankle dorsiflexion range of motion is commonly measured during the weight-bearing lunge test (WBLT) as the horizontal knee distance traveled or tibial inclination. These measures are assumed to represent talocrural dorsiflexion, yet have not been validated against radiographic images.

OBJECTIVES

To determine the (1) contribution of the talocrural joint to tibial inclination during the WBLT, (2) validity of inclinometer and photographic measures of tibial inclination compared to radiographic images, and (3) the association between tibial inclination and horizontal distance measures.

METHODS

Tibial inclination using an inclinometer, horizontal distance via a ruler, and radiographic and photographic images were recorded in 20 participants in standing and during the end-range WBLT. Two assessors used computer software to measure talar rotation and tibial inclination from digital radiographs and photographs. The limits of agreement between photographic and inclinometer measures compared to radiographic measures, as well as correlations between measures, were calculated.

RESULTS

In the end-range WBLT, 91.8% of motion occurred at the talocrural joint, with 8.2% occurring distally. There were very strong correlations (all, r 0.88, P<.001) between end-range radiographic and photographic measures, radiographic and inclinometer measures, and radiographic, inclinometer, and photographic measures of tibial inclination and horizontal lunge distance. Calculation of the limits of agreement indicated unacceptable agreement between inclinometer and radiographic measures (-7.84°, 5.92°) and acceptable agreement between photographic and radiographic measures (-2.17°, 2.49°).

CONCLUSION

Tibial inclination during the WBLT primarily occurs at the talocrural joint. While inclinometer and photographic measures of tibial inclination can reliably be used clinically to measure dorsiflexion range of motion during the WBLT, inclinometer results differ slightly from those obtained via radiographs. J Orthop Sports Phys Ther 2019;49(12):934-941. Epub 23 Jul 2019. doi:10.2519/jospt.2019.8697.

Physical Therapists' Use of Evaluation Measures to Inform the Prescription of Ankle-Foot Orthoses for Children with Cerebral Palsy

Aims: To examine how physical therapists (PTs) use evaluation measures to guide prescription and re-assessment of ankle-foot orthoses (AFOs) for children with CP. Methods: PTs in Canada who work with children with CP were invited to complete an online survey. Survey questions examined PT evaluation and interpretation of findings at initial AFO prescription and re-assessment. Closed-ended responses were analyzed using descriptive statistics, and a conventional content analysis examined responses to open-ended questions. Results: Sixty responses from ten provinces were analyzed. Three themes emerged from the open-ended responses, which were supported by closed-ended responses. (1) Focus on impairment-level measures. Although evaluation primarily involved observational, non-standardized measures of impairments and gait pattern, most respondents also considered participation-level constructs. (2) Lack of confidence/knowledge. Respondents reported a moderate level of confidence concerning decision-making about AFO type and characteristics. 3) Inconsistent practices between therapists, possibly reflecting the paucity of available evidence or individualization of the prescription. Conclusions: Non-standardized, observational assessment methods, and impairment-level constructs appear to guide AFO prescription decisions. Integrating current knowledge into practice, developing best practice guidelines, and developing standardized tools to assess the effects of AFOs on participation may promote confidence, consistency, and improved outcomes.

Weight bearing versus non-weight bearing ankle dorsiflexion measurement in people with diabetes: a cross sectional study

Background

Accurate measurement of ankle dorsiflexion is important in both research and clinical practice as restricted motion has been associated with many foot pathologies and increased risk of ulcer in people with diabetes. This study aimed to determine the level of association between non-weight bearing versus weight bearing ankle dorsiflexion in adults with and without diabetes, and to evaluate the reliability of the measurement tools.

Methods

One hundred and thirty-six adults with diabetes and 30 adults without diabetes underwent ankle dorsiflexion measurement non-weight bearing, using a modified Lidcombe template, and weight bearing, using a Lunge test. Pearson product-moment correlation coefficients, intraclass correlation coefficients (ICCs) with 95% confidence intervals, standard error of measurement and minimal detectable change were determined.

Results

There was a moderate correlation (r = 0.62–0.67) between weight and non-weight bearing tests in the non-diabetes group, and a negligible correlation in the diabetes group(r = 0.004–0.007). Intratester reliability was excellent in both groups for the modified Lidcombe template (ICC = 0.89–0.94) and a Lunge test (ICC = 0.83–0.89). Intertester reliability was also excellent in both groups for the Lidcombe template (ICC = 0.91) and a Lunge test (ICC = 0.88–0.93).

Conclusions

We found the modified Lidcombe template and a Lunge test to be reliable tests to measure non-weight bearing and weight bearing ankle dorsiflexion in adults with and without diabetes. While both methods are reliable, further definition of weight bearing ankle dorsiflexion normative ranges may be more relevant for clinical practice.

Influence of ankle dorsiflexion range of motion on heel-rise time during gait

[Purpose] The purpose of this study was to examine the correlation between weight-bearing (WB) and non-WB ankle dorsiflexion (DF) range of motion (ROM) and ankle movement during gait, including heel-rise time and ankle DF at heel-rise. [Subjects and Methods] Thirty healthy male subjects were recruited for this study. Ankle DF ROM of both feet was measured under the WB and non-WB conditions. Heel-rise time and ankle DF at heel-rise in both feet during gait were measured using a motion analysis system. Pearson product moment correlations were used to identify correlation ankle DF ROM and ankle movement during gait. [Results] Heel-rise time and ankle DF at heel rise were significantly correlated with WB ankle DF ROM. However, no correlations were found between ankle movement during gait and non-WB ankle DF ROM. [Conclusion] These findings demonstrate that WB ankle DF ROM measurements can be used to predict heel-rise time and ankle DF at heel-rise.

Equinus and Lengthening Techniques

Equinus is linked to most lower extremity biomechanically related disorders. Defining equinus as ankle joint dorsiflexion less than 5° of dorsiflexion with the knee extended is the basis for evaluation and management of the deformity. Consistent evaluation methodology using a goniometer with the subtalar joint in neutral position and midtarsal joint supinated while dorsiflexing the ankle with knee extended provides a consistent clinical examination. For equinus deformity with an associated disorder, comprehensive treatment mandates treatment of the equinus deformity. Surgical treatment of equinus offers multiple procedures but the Baumann gastrocnemius recession is preferred based on deformity correction without weakness.

Flatfoot and obesity in school-age children: a cross-sectional study

Childhood obesity exerts abnormally high stresses on developing foot structures which can lead to structural deformity of the foot. Screening for foot problems in children with overweight helps detect interior risks restricting normal lifestyle in these individuals. The purpose of this study was to investigate the effects of excess weight on the structure and function of the developing foot in students aged 7-14 years. A total of 667 participants were recruited for this cross-sectional study via a multi-level cluster sampling method (randomization was used within each cluster). All subjects (340 boys and 327 girls) attended primary and secondary schools in Isfahan City, Iran. The children's feet were evaluated using clinical assessments and footprint-based measures whilst fully weight bearing. Significant differences were observed in the frequency of flatfoot between normal weight, overweight and obese groups (P < 0.001); participants who were more overweight had flatter feet. Children with higher weight also had a more pronated heel, less dorsiflexion range and higher reported pain within physical activity. This study indicated that childhood obesity is associated with structural foot and ankle deformities and activity-related foot pain.

Flatfoot in school-age children: prevalence and associated factors

BACKGROUND

Flatfoot has been shown to cause abnormal stresses on the foot and lower extremity. The altered mechanical stresses on these structures can aggravate the foot deformity. Screening of the flatfoot and its associated factors helps detect underlying risks influencing the stresses on the foot. The purpose of this study was to analyze the structure of the medial foot arch and investigate its associated factors in students, aged 7 to 14 years.

METHODS

Multistage cluster sampling was used and each cluster included 2 other random sampling levels. A total of 667 Iranian school children were recruited and their feet were bilaterally evaluated using a static footprint while standing in a fully weightbearing position. The footprint, an observational measurement, and a questionnaire were used for the foot assessment.

RESULTS

The prevalence of flatfoot was 17.1% in the population studied. There was no gender difference but the prevalence of flatfoot did decrease with age. The significant differences were observed in the prevalence of flatfoot between normal-weight, overweight, and obese groups (P < .01); more overweight participants had flatter feet.

CONCLUSION

This study demonstrated that development of the longitudinal plantar arch in school-age children is influenced by age and weight. Age and weight were the primary predictive factors of flatfoot.

LEVELS OF EVIDENCE

Prognostic, Level IV: Case series.

Effect of treadmill walking with ankle stretching orthosis on ankle flexibility and gait

[Purpose] The purpose of this study was to evaluate the kinematics of the ankle in the lunge to estabilish effectiveness of an ankle stretching orthosis (ASO) on the ankle dorsiflexion range of motion (ROM) of individuals with limited dorsiflexion ROM. [Subjects and Methods] Forty ankles with decreased dorsiflexion ROM of 20 participants were evaluated in this study. After wearing the ASO, participants walked on a treadmill for 15 minutes. Participants walked on the treadmill at a self-selected comfortable speed. Ankle dorsiflexion ROM, maximum dorsiflexion ROM before heel-off, and time to heel-off during the stance phase of gait were measured before and after 15 minutes of treadmill walking with the ASO. The differences in all variables between before and after treadmill walking with ASO were analyzed using the paired t-test. [Results] Ankle active and passive ROM, and dorsiflexion ROM during lunge increased significantly after treadmill walking with ASO. Treadmill walking with the ASO significantly increased the angle of maximal dorsiflexion before heel-off and time to heel-off during the stance phase. [Conclusion] The results of this study show that treadmill walking with the ASO effectively improved ankle flexibility and restored the normal gait pattern of the ankle joint by increasing dorsiflexion ROM, maximal angle of dorsiflexion, and time to heel-off in the stance phase.

Immediate combined effect of gastrocnemius stretching and sustained talocrural joint mobilization in individuals with limited ankle dorsiflexion: A randomized controlled trial

BACKGROUND

Although gastrocnemius stretching and talocrural joint mobilization have been suggested as effective interventions to address limited ankle dorsiflexion passive range of motion (DF PROM), the effects of a combination of the two interventions have not been identified.

OBJECTIVE

The aim of the present study was to compare the effects of gastrocnemius stretching combined with joint mobilization and gastrocnemius stretching alone.

DESIGN

A randomized controlled trial.

METHODS

In total, 24 individuals with limited ankle DF PROM were randomized to undergo gastrocnemius stretching combined with joint mobilization (12 feet in 12 individuals) or gastrocnemius stretching alone (12 feet in 12 individuals) for 5 min. Ankle kinematics during gait (time to heel-off and ankle DF before heel-off), ankle DF PROM, posterior talar glide, and displacement of the myotendinous junction (MTJ) of the gastrocnemius were assessed before and after the interventions. The groups were compared using two-way repeated measures analysis of variance.

RESULTS/FINDINGS

Greater increases in the time to heel-off and ankle DF before heel-off during gait and posterior talar glide were observed in the stretching combined with joint mobilization group versus the stretching alone group. Ankle DF PROM and displacement of the MTJ of the gastrocnemius were increased significantly after the interventions in both groups, with no significant difference between them.

CONCLUSIONS

These findings suggest that gastrocnemius stretching with joint mobilization needs to be considered to improve ankle kinematics during gait.

Musculoskeletal and activity-related factors associated with plantar heel pain

BACKGROUND

Despite the prevalence and impact of plantar heel pain, its etiology remains poorly understood, and there is no consensus regarding optimum management. The identification of musculoskeletal factors related to the presence of plantar heel pain could lead to the development of better targeted intervention strategies and potentially improve clinical outcomes. The aim of this study was to investigate relationships between a number of musculoskeletal and activity-related measures and plantar heel pain.

METHODS

In total, 202 people with plantar heel pain and 70 asymptomatic control participants were compared on a variety of musculoskeletal and activity-related measures, including body mass index (BMI), foot and ankle muscle strength, calf endurance, ankle and first metatarsophalangeal (MTP) joint range of motion, foot alignment, occupational standing time, exercise level, and generalized hypermobility. Following a comparison of groups for parity of age, analyses of covariance were performed to detect differences between the 2 groups for any of the variables measured.

RESULTS

The plantar heel pain group displayed a higher BMI, reduced ankle dorsiflexion range of motion, reduced ankle evertor and toe flexor strength, and an altered inversion/eversion strength ratio. There were no differences between groups for foot alignment, dorsiflexor or invertor strength, ankle inversion or eversion range of motion, first MTP joint extension range of motion, generalized hypermobility, occupational standing time, or exercise level.

CONCLUSION

Plantar heel pain is associated with higher BMI and reductions in some foot and ankle strength and flexibility measures. Although these factors could be either causal or consequential, they are all potentially modifiable and could be targeted in the management of plantar heel pain.

LEVEL OF EVIDENCE

Level III, comparative study.

Three-dimensional analysis of foot motion after uphill walking with mobilization with movement using tape applied to the talocrural joint in women with limited ankle dorsiflexion

BACKGROUND

Previous studies that investigated mobilization with movement (MWM) treatment assessed only improvements in passive range of motion (ROM). No information is currently available regarding the efficacy of modified MWM by application of tape. Therefore, we investigated the effect of uphill walking with modified MWM using tape applied to the talocrural joint (uphill walking with MWM taping) in women with limited ankle dorsiflexion.

METHODS

Twelve feet of 12 women with ankle dorsiflexion < 8 degrees were studied. Passive ROM measured using a goniometer was used to select participants. Participants walked on a level walkway under 3 conditions: before exercise, after uphill walking, and after uphill walking with MWM taping. The Oxford Foot Model using 3D motion analysis system was used to examine dynamic foot kinematics, and statistical significance was determined by 1-way repeated-measures analysis of variance.

RESULTS

After uphill walking with MWM taping, peak hindfoot dorsiflexion relative to the tibia was significantly greater than that before exercise and after uphill walking. Furthermore, peak forefoot plantarflexion relative to the hindfoot, peak hindfoot plantarflexion relative to the tibia, and backward tilt of the tibia were greater than those before exercise.

CONCLUSIONS

Uphill walking with MWM taping resulted in an immediate alteration in foot motion during walking, increasing hindfoot dorsiflexion in particular.

CLINICAL RELEVANCE

Further studies are needed to investigate the long-term effects of uphill walking with MWM taping and its potential use in rehabilitation training.

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.

The effect of subtalar joint position on dorsiflexion of the ankle/rearfoot versus midfoot/forefoot during gastrocnemius stretching

BACKGROUND

Limited ankle joint dorsiflexion passive range of motion (PROM) has been associated with common chronic lower extremity conditions, and clinicians often instruct patients in stretching exercises to increase dorsiflexion. However, little is known about how subtalar joint (STJ) position affects dorsiflexion at the midfoot/forefoot versus ankle/rearfoot during gastrocnemius stretching. The purpose of this study was to determine if more dorsiflexion occurs at the ankle/rearfoot and less at the midfoot/forefoot during gastrocnemius stretching with the STJ positioned in supination versus pronation.

METHODS

In this repeated measures design, 27 participants (23 females, 4 males; mean age = 31.3 years, SD = 10.7) with current or recent history of lower extremity chronic conditions and less than 10 degrees ankle dorsiflexion measured with the knee in extension on the involved side(s) performed five 30-second gastrocnemius stretching trials in pronation and supination on each side in a randomly determined sequence. A 7-camera Vicon Motion Analysis System and an AMTI force plate were used to measure midfoot/forefoot dorsiflexion, ankle/rearfoot dorsiflexion, knee extension, and normalized vertical ground reaction force.

RESULTS

Two-way repeated measures ANOVA revealed a significant increase in midfoot/forefoot dorsiflexion when stretching in pronation compared to supination (P < .001). ANOVAs also demonstrated significantly more extension of the knee when stretching in supination compared to pronation (P < .001), and increased normalized vertical ground reaction force when stretching in supination compared to pronation (P = .032). With the numbers available, no significant difference in ankle/rearfoot dorsiflexion when stretching in supination compared to pronation could be detected (P > .05).

CONCLUSION

Gastrocnemius stretching in pronation resulted in more dorsiflexion at the midfoot/forefoot than stretching in supination.

CLINICAL RELEVANCE

Clinicians may want to consider STJ position during gastrocnemius stretching to either facilitate or limit recruitment of dorsiflexion motion at the midfoot/forefoot.

Sagittal plane kinematics of the foot during passive ankle dorsiflexion

BACKGROUND

Measurement of ankle joint dorsiflexion is an essential examination technique that needs to be performed prior to prescription of foot orthoses since the presence or absence of ankle equinus will affect the design of such devices. The purpose of this study was to investigate the effect of foot posture on sagittal plane kinematics of various foot segments during passive dorsiflexion.

STUDY DESIGN

Comparative repeated measures design.

OBJECTIVES

To determine the effect of foot posture on inter segmental kinematics during passive dorsiflexion.

METHODS

An optoelectronic movement analysis system was employed to collect kinematic data. A validated marker set (Oxford Foot Model) was applied to 16 subjects (12 males, 4 females) with a mean age of 35.5 years (range 20-56 years), who provided informed consent. An upward force was applied to the forefoot until maximum resistance. Sagittal movement of the hindfoot and forefoot segments along with the whole foot movement were analyzed in the pronated, neutral and supinated foot postures.

RESULTS

While maximum foot dorsiflexion angle showed a significant difference between the three postures (p = 0.000) the actual recorded difference between the neutral and supinated postures was only 2.49°. For the hindfoot and forefoot segments, mean angle range of movement for the pronated foot posture was significantly higher than the other foot postures. The forefoot to hindfoot angle demonstrated a significant (p = 0.005) increase during dorsiflexion between the pronated and supinated postures. These results indicate that during passive dorsiflexion, the forefoot travels through a greater degree of movement than the hindfoot.

CONCLUSIONS

While the maximum foot dorsiflexion angle differs significantly between the pronated and supinated foot postures, hindfoot movement also varies significantly between foot postures. Furthermore, the forefoot to tibia angle travels through a greater range than the hindfoot to tibia angle, in all three foot postures. The hindfoot to forefoot angle does not remain constant during passive dorsiflexion, but increases upon application of a dorsiflexing force, indicating that the forefoot movement cannot be eliminated completely by placing the foot in any particular posture.

Effect of heel lifts on plantarflexor and dorsiflexor activity during gait

BACKGROUND

Previous investigators have shown that high heels decrease the muscle activity of the gastrocnemius muscle during gait. However, it is not known whether commonly used in-shoe heel lifts of lower heights will demonstrate similar effects on muscle activity. The aim of this study was to determine whether heel lifts alter the muscle activity of the ankle plantarflexors and dorsiflexors during the stance phase of gait among individuals with limited gastrocnemius extensibility.

MATERIALS AND METHODS

This study used a repeated measures design. Twenty-four healthy volunteers (12 males and 12 females) with less than 5 degrees of passive ankle dorsiflexion with the knee extended participated in the study. Electromyography (EMG), computerized motion analysis, and a force plate were used to measure mean muscle activity of the lateral gastrocnemius, medial gastrocnemius, soleus and tibialis anterior muscles during the stance phase of gait across three walking conditions. Muscle activity was measured as participants ambulated at a self-selected speed in athletic shoes alone and with heel lifts of 6 mm and 9 mm inserted in athletic shoes.

RESULTS

Between heel-strike and heel-off, the mean EMG amplitude of the medial gastrocnemius increased with both 6 and 9 mm heel lifts and the amplitude of the tibialis anterior increased with 9 mm heel lifts compared to shoes alone. Between heel-strike and heel-off, there were no significant differences in mean EMG amplitude of the lateral gastrocnemius or soleus muscles walking in heel lifts compared to shoes alone. Between heel-off and toe-off, there were no significant differences in mean EMG amplitude of the lateral gastrocnemius, medial gastrocnemius, soleus, or tibialis anterior muscles when walking in heel lifts compared to shoes alone.

CONCLUSION

Heel lifts increase muscle activity of the medial gastrocnemius and tibialis anterior muscles between heel-strike and heel-off among individuals with limited gastrocnemius extensibility.

CLINICAL RELEVANCE

We were unable to confirm a decrease in muscle activity when using heel lifts.

Effect of medial arch support on displacement of the myotendinous junction of the gastrocnemius during standing wall stretching

STUDY DESIGN

Controlled laboratory study.

OBJECTIVES

To examine the effects of standing wall stretching with and without medial arch support (WMAS versus WOMAS) on the displacement of the myotendinous junction (DMTJ) of the medial gastrocnemius, rearfoot angle, and navicular height in subjects with neutral foot alignment and pes planus.

BACKGROUND

Standing wall stretching is often prescribed to increase ankle dorsiflexion range of motion for sports fitness and rehabilitation. However, the effect of standing wall stretching WMAS on DMTJ is unknown.

METHODS

Fifteen subjects with neutral foot alignment and 15 subjects with pes planus performed standing wall stretching under WMAS and WOMAS conditions. Measurements of DMTJ and rearfoot position were performed using ultrasonography and video imaging. Navicular height was measured using a ruler. Dependent variables were examined with a 2-way mixed-design analysis of variance. The 2 factors were foot type (neutral foot versus pes planus) and stretching condition (WMAS versus WOMAS).

RESULTS

There were significant interactions of medial arch support by foot type for DMTJ, rearfoot angle, and navicular drop (P<.001). A post hoc paired t test showed that standing wall stretching in the WMAS condition significantly increased the DMTJ, compared to stretching in the WOMAS condition, in subjects with neutral foot (mean +/- SD, 9.6 +/- 1.6 versus 10.5 +/- 1.6 mm; difference, 0.9 mm; 99% CI: 0.4-1.4 mm) and in those with pes planus (10.0 +/- 1.8 versus 12.7 +/- 2.0 mm; difference, 2.7 mm; 99% CI: 1.9-3.5 mm) (P<.001). When comparing WOMAS and WMAS, the difference in DMTJ (1.8 mm; 99% CI: 0.9-2.7 mm) was significantly greater in subjects with pes planus than in those with neutral foot (P<.001).

CONCLUSION

Standing wall stretching with medial arch support maintained subtalar joint neutral position and increased the length of the gastrocnemius in subjects with pes planus. When prescribing standing wall stretching, clinicians need to emphasize the use of medial arch support to effectively stretch the gastrocnemius in subjects with pes planus.

Subtalar joint position during gastrocnemius stretching and ankle dorsiflexion range of motion

CONTEXT

Gastrocnemius stretching exercises often are prescribed as part of the treatment program for patients with overuse injuries associated with limited ankle dorsiflexion. However, little is known about how the position of the subtalar joint during gastrocnemius stretching affects ankle dorsiflexion range of motion (ROM).

OBJECTIVE

To determine the effect of subtalar joint position during gastrocnemius stretching on ankle dorsiflexion ROM.

DESIGN

This study was a 3-way mixed-model design. The 3 factors were subtalar joint position (supinated, pronated), lower extremity (experimental, control), and time (pretest, posttest). Lower extremity and time were the repeated measures.

SETTING

University research laboratory.

PATIENTS OR OTHER PARTICIPANTS

Thirty-three healthy volunteers (29 women, 4 men).

INTERVENTION(S)

Participants performed a gastrocnemius stretching exercise 2 times daily for 3 weeks with the subtalar joint of the randomly assigned experimental side (dominant or nondominant) in the randomly assigned position (supination or pronation). The contralateral lower extremity served as the control.

MAIN OUTCOME MEASURE(S)

Before and after the 3-week gastrocnemius stretching program, we used goniometers to measure ankle dorsiflexion ROM in weight-bearing and non-weight-bearing positions with the subtalar joint positioned in anatomic 0 degrees .

RESULTS

Ankle dorsiflexion ROM measured in weight-bearing and non-weight-bearing positions increased after the gastrocnemius stretching program (P = .034 and .003, respectively), but the increase in ROM did not differ based on subtalar joint position (P = .775 and .831, respectively).

CONCLUSIONS

Subtalar joint position did not appear to influence gains in ankle dorsiflexion ROM after a gastrocnemius stretching program in healthy volunteers.