Dynamic foot movement in children treated for congenital talipes equinovarus

Kinematic Gait Impairments in Children with Clubfeet Treated by the Ponseti Method: A Systematic Review and Meta-Analysis

BACKGROUND

Being aware of possible gait impairments in Ponseti-treated clubfoot children might be useful for optimizing initial and additional treatment. Therefore, this systematic review and meta-analysis aimed to identify kinematic gait abnormalities in children with clubfoot treated with the Ponseti method (with and without relapse).

METHODS

A systematic search was conducted. Studies comparing kinematic gait parameters of Ponseti-treated clubfoot children to healthy controls were included. Meta-analyses and qualitative analyses were conducted on the extracted data.

RESULTS

Twenty studies were identified. Twelve of the 153 reported kinematic outcome measures could be included in the meta-analysis. Plantarflexion at push-off, maximum ankle dorsiflexion during the swing, maximal plantarflexion, and ankle range of motion was significantly lower in Ponseti-treated clubfoot children. Ponseti-treated clubfoot children showed more internal foot progression. Qualitative analysis revealed 51 parameters in which pre-treatment relapse clubfeet deviated from healthy controls.

CONCLUSIONS

Ponseti-treated clubfoot children showed several kinematic gait differences from healthy controls. In future studies, homogeneity in measured variables and study population and implementation of multi-segmental foot models will aid in comparing studies and understanding clubfoot complexity and treatment outcomes. The question remains as to what functional problems gait impairments lead to and whether additional treatment could address these problems.

Biomechanical Implications of Congenital Conditions of the Foot/Ankle

Segmental foot and ankle models are often used as part of instrumented gait analysis when planning interventions for complex congenital foot conditions. More than 40 models have been used for clinical analysis, and it is important to understand the technical differences among models. These models have been used to improve clinical planning of pediatric foot conditions including clubfoot, planovalgus, and equinovarus. They have also been used to identify clinically relevant subgroups among pediatric populations, quantify postoperative outcomes, and explain variability in healthy populations.

Forefoot adduction and forefoot supination as kinematic indicators of relapse clubfoot

BACKGROUND

Understanding the kinematic characteristics of relapse clubfoot compared to successfully treated clubfoot could aid early identification of a relapse and improve treatment planning. The usage of a multi segment foot model is essential in order to grasp the full complexity of the multi-planar and multi-joint deformity of the clubfoot.

RESEARCH QUESTION

The purpose of this study was to identify differences in foot kinematics, using a multi-segment foot model, during gait between patients with Ponseti treated clubfoot with and without a relapse and age-matched healthy controls.

METHODS

A cross-sectional study was carried out including 11 patients with relapse clubfoot, 11 patients with clubfoot and 15 controls. Gait analysis was performed using an extended Helen Hayes model combined with the Oxford Foot Model. Statistical analysis included statistical parametric mapping and discrete analysis of kinematic gait parameters of the pelvis, hip, knee, ankle, hindfoot and forefoot in the sagittal, frontal and transversal plane.

RESULTS

The relapse group showed significantly increased forefoot adduction in relation with the hindfoot and the tibia. Furthermore, this group showed increased forefoot supination in relation with the tibia during stance, whereas during swing increased forefoot supination in relation with the hindfoot was found in patients with relapse clubfoot compared with non-relapse clubfoot.

SIGNIFICANCE

Forefoot adduction and forefoot supination could be kinematic indicators of relapse clubfoot, which might be useful in early identification of a relapse clubfoot. Subsequently, this could aid the optimization of clinical decision making and treatment planning for children with clubfoot.

This is a narrative review of the functional evaluation of clubfoot treatment with gait analysis

Clinicians worldwide have embraced Ponseti’s nonoperative approach in the treatment of clubfoot, primarily due to ubiquitous reports of successful outcomes. A crucial component in this measured success, has come from researchers assessing long-term physical function following nonoperative treatment. Gait analysis has been instrumental in objectively evaluating lower extremity kinematics and kinetics while plantar pressures demonstrate the load bearing patterns experienced in the foot. As technology improves, our ability to evaluate function can take place both in the laboratory setting, and in the community. For over 20 years, our institution has been studying the gait patterns of children treated for clubfoot. After adopting the nonoperative approach, we established a prospective research program that has allowed us to study functional outcomes in the very young walker, through growth to adolescents, and finally at skeletal maturity. We have seen over 450 children treated for clubfoot in the Movement Science Lab, for over 1,250 gait assessments over the span of this study. Early results in 105 children (154 feet) treated nonoperatively for clubfoot, showed 56% of children had normal sagittal plane ankle kinematics, however an incidence of 48% of Ponseti feet had increased dorsiflexion in stance phase, leading us to wonder if this was the result of the tenotomy. Intermediate follow up at age 5 years, showed that the incidence of increased dorsiflexion was reduced (24%) and ankle power did not appear to be affected (P>0.05 compared to controls). The research highlighted in this paper presents the application of functional evaluation through growth and the long-term effects of nonoperative treatment on gait and function. This is a review of the functional outcome studies from our experience at Scottish Rite for Children.

Talipes Equinovarus Treatment in Infants Treated by the Ponseti Method Compared With Posterior-Only Release: A Mid-Childhood Comparison of Results

The aim of this study is to evaluate children in middle childhood with clubfoot treated with Ponseti method vs posterior-only release and to compare their results to a control group with 4 modules (physical examination, gait study, radiographic measurements, and questionnaires). From 01/01/2004 until 01/01/2009, 31 children (45 feet) were treated with the posterior-only release protocol and 22 patients (34 feet) were treated with the Ponseti method. In 2016, patients were evaluated and compared with 25 children without neuromuscular disorders. Parents completed 3 outcome questionnaires. Radiographs evaluated residual deformity and osteoarthritis. A physical examination and a 3-dimensional gait analysis were performed to evaluate range of motion, kinematic, and kinetic data. Recurrence rate was similar between treatment groups; however, type of surgery to treat residual deformity was more aggressive in the posterior-only release (91% required major surgery), p = .024. Radiographic examination showed similar residual deformity with greater hindfoot varus in posterior-only release (68%), p = .02. Reduced cadence, increased stance dorsiflexion, calcaneus gait and forced eversion prior to swing were the main characteristics of gait in posterior-only release. Four (11%) feet treated with posterior-only release vs 11 (33%) feet treated with Ponseti method had a normal gait, p = .016. Our study showed that biomechanical function and long-term outcomes of children in middle childhood treated with the Ponseti method more closely compare with healthy individuals than those treated using posterior-only surgical technique.

Normalization of Forefoot Supination After Tibialis Anterior Tendon Transfer for Dynamic Clubfoot Recurrence

BACKGROUND

We aimed to evaluate the effect of tibialis anterior tendon transfer (TATT) on foot motion in children with clubfoot recurrence after initial Ponseti treatment.

METHODS

Children with dynamic clubfoot recurrence after initial Ponseti treatment who underwent TATT between 2014 and 2017 were considered for inclusion. Exclusion criteria were neurological disease, split transfer of the tendon, additional bone or joint invasive surgery, and initial treatment abroad. Of 94 children (143 TATT), 36 met the inclusion criteria. Seventeen (47%) of the 36 children with 25 clubfeet and a mean age at the time of surgery of 6.8 years participated in the study. Gait analysis, including the Oxford foot model, was conducted preoperatively and postoperatively. Furthermore, kinematic and kinetic data were compared with those of age-matched healthy children (n=18).

RESULTS

Forefoot supination in relation to the hindfoot and tibia was reduced during swing and at initial contact after TATT compared with preoperative values. Forefoot supination in relation to the tibia at initial contact decreased from 12.4 to 5.2 degrees after TATT (control group, 6.0 degrees). The heel showed less dynamic varus and adduction movement after TATT compared with preoperatively. Maximum ankle power was reduced preoperatively and postoperatively compared with controls. Maximum ankle dorsiflexion slightly increased after TATT.

CONCLUSIONS

Gait analysis showed normalization of the main components of dynamic clubfoot recurrence after TATT. This joint-sparing surgery efficiently corrects recurrent dynamic deformity.

LEVEL OF EVIDENCE

Level II-therapeutic.

Design and validation of a foot-ankle dynamic simulator with a 6-degree-of-freedom parallel mechanism

An in vitro simulation test using a designed well-targeted test rig has been regarded as an effective way to understand the kinematics and dynamics of the foot and ankle complex in the dynamic stance phase, and it also allows alterations in both internal and external control compared to in vivo tests. However, current simulators are limited by some assumptions. In this study, a novel foot and ankle bionic dynamic simulator was developed and validated. A movable 6-degree-of-freedom parallel mechanism, known as Steward platform, was used as the core structure to drive the tibia, with a tibial force actuator applied with different loads. Four major muscle groups were actuated by four sensored pulling cables connected to muscle tendons. Simulation processes were controlled using a software developed based on a proportional-integral-derivative control loop, with tension-compression sensors mounted on tendon pulling cables and used as real-time monitor signals. An iterative learning module for tibial force control was integrated into the control software. Six specimens of the cadaveric foot-ankle were used to validate the simulator. The stance phase was successfully simulated within 5 s, and the tibia loads were applied based on the body weight of the cadaveric specimen donors. Typical three-dimensional ground reaction forces were successfully reproduced. The coefficient of multiple correlation analysis demonstrated good repeatability of the dynamic simulator for the ground reaction force (coefficient of multiple correlation > 0.89) and the range of ankle motion (coefficient of multiple correlation > 0.87 with only one exception). The simulated ranges of the foot-ankle joint rotation in stance were consistent with in vivo measurements, indicating the success of the dynamic simulation process. The proposed dynamic simulator can enhance the understanding of the mechanism of the foot-ankle movement, related injury prevention, and surgical intervention.

In-toeing gait in children with clubfoot and the effect of tibial rotation osteotomy

In-toeing gait is common after treatment for clubfoot deformity and is often secondary to residual internal tibial torsion. The purpose of the current study was to characterize the gait pattern in children with an intoeing gait pattern associated with talipes equinovarus (TEV) deformity, identify secondary changes at the hip that occur with intoeing, and determine if these secondary effects resolve after correction of tibial torsion. Patients with a diagnosis of TEV deformity, in-toeing gait secondary to residual internal tibial torsion corrected with tibial rotation osteotomy (TRO) and complete preoperative and postoperative motion analysis studies obtained approximately 1 year apart, were included in the study. Nineteen children (19 left extremities) with a TRO at a mean age of 8.2 years met inclusion criteria. Clinical examination showed improvement in tibial torsion assessment by measure of the thigh foot axis and transmalleolar axis. Kinematically, an abnormal internal FPA was present in all cases preoperatively, was corrected to normal in 12 (63%), remained internal in 5 (26%), and was abnormally external in 2 (11%). External hip rotation was identified in 13 (68%) cases preoperatively. Hip rotation was normalized postoperatively in 7 (54%), and was unchanged in the remaining 6 (46%). TRO provides effective correction of excessive internal tibial torsion, resolution of kinematic internal knee rotation, and normalization of the internal foot progression angle in the majority of patients with TEV deformity. External hip rotation resolved in approximately 50% of cases. Overcorrection of the internal FPA is possible when secondary changes at the hip do not resolve.

Does an overcorrected clubfoot caused by surgery or by the Ponseti method behave differently?

BACKGROUND

Overcorrection is a recognized problem following surgical treatment of congenital clubfoot. Recently this complication has also been mentioned following Ponseti treatment.

RESEARCH QUESTION

Do overcorrected clubfeet (OCCF) caused by surgery behave differently from those caused by Ponseti treatment in terms of segmental motion of the feet and show differences in the severity of deformity on X-rays?

METHODS

Children between 7 and 12 years with OCCF were included in this study. Depending on the aetiology causing them, the feet were divided into 2 groups (Ponseti and peritalar release surgery). 25 typically developing children served as controls. All subjects were subjected to clinical and radiological examination and 3-Dimensional gait analysis using the Oxford Foot Model.

RESULTS

Thirty-two children with OCCF, of these 18 feet in the surgical and 14 feet in the Ponseti group, were included in the study. No radiological differences were seen in the flatfoot parameters between OCCF groups except in the calcaneal inclination angle that was more pathological in the Ponseti group. The clinical ankle plantar flexion was significantly reduced in the surgical group. During walking the range motion of the hindfoot in the frontal plane was significantly reduced in surgically treated feet compared to the Ponseti group. The other parameters did not show any significant difference between groups.

SIGNIFICANCE

The overcorrected clubfeet following surgery and Ponseti showed similar appearance and showed no significant differences in 11/12 radiological parameters. The segmental motion of the feet showed no significant differences between groups except the in the range of motion of the subtalar eversion. A considerable subtalar joint motion was present even in the surgical group. These findings might help plan the treatment of these feet.

A Long-term Follow-up of Young Adults With Idiopathic Clubfoot: Does Foot Morphology Relate to Pain?

BACKGROUND

Individuals with clubfoot, treated in infancy with either the Ponseti method or comprehensive clubfoot release, often encounter pain as adults. Multiple studies have characterized residual deformity after Ponseti or surgical correction using physical exam, radiographs and pedobarography; however, the relationship between residual foot deformity and pain is not well defined. The purpose of the current study was 2-fold: (1) to evaluate the relationship between foot morphology and pain for young adults treated as infants for idiopathic clubfoot and (2) to describe and compare pedobarographic measures and outcome measures of pain and morphology among surgically treated, Ponseti treated, and typically developing feet.

METHODS

We performed a case-control study of individuals treated for clubfoot at 2 separate institutions with either the Ponseti method or comprehensive clubfoot release between 1983 and 1987. All subjects (24 treated with comprehensive clubfoot release, 18 with Ponseti method, and 48 controls) were evaluated using the International Clubfoot Study Group (ICFSG) morphology scoring, dynamic pedobarography, and foot function index surveys. During pedobarography, we collected the subarch angle and arch index as well as the center of pressure progression (COPP) on all subjects.

RESULTS

Foot morphology (ICFSG) scores were highly correlated with foot function index pain scores (r=0.43; P<0.001), although the difference in pain scores between the surgical and Ponseti group did not reach significance. The surgical group exhibited greater subarch angle and arch indexes than the Ponseti group, demonstrating a significant difference in morphology, a flatter foot. Finally, we found more abnormalities in foot progression, decreased COPP in the forefoot and increased COPP in the midfoot and hindfoot, in the surgical group compared with controls.

CONCLUSIONS

Measures of foot morphology were correlated with pain among all treated for clubfoot. Compared with Ponseti method, comprehensive surgical release lead to greater long-term foot deformity, flatter feet and greater hindfoot loading time.

LEVEL OF EVIDENCE

Level III-Therapeutic.

Lower extremity characteristics in recurrent clubfoot: Clinical and gait analysis findings that may influence decisions for additional surgery

BACKGROUND

Patients with recurrent clubfoot may seek intervention to address impairments that impact gait function. An understanding of these impairments and associated gait issues will provide valuable information about ongoing treatment requirements.

RESEARCH QUESTION

The purpose of this study was to describe the prevalence of impairments and associated gait deviations in children with recurrent clubfoot and to evaluate whether these findings differ depending on unilateral or bilateral presentation.

METHODS

Eighty-four affected feet (42 unilateral, 21 bilateral) were retrospectively reviewed. History, clinical exam, and gait data were collected. Statistical analysis included evaluations of associations between clinical exam and gait parameters and differences among patients with unilateral versus bilateral clubfoot and a database of healthy controls.

RESULTS

The average age was 7.5 ± 3.3 years for unilateral and 7.0 ± 2.8 years for bilateral patients. Patients presented with limited passive ankle dorsiflexion (unilateral/bilateral:67%/57%), limited ankle plantar flexion strength (unilateral/bilateral:53%/55%), metatarsus adductus (unilateral/bilateral:86%/83%) and internal foot-thigh angles (unilateral/bilateral:83%/82%), while only a subset presented with internal bi-malleolar axis angles (unilateral/bilateral:36%/45%). The most common gait deviations were internal foot progression (unilateral/bilateral:76%/73%), external hip rotation (unilateral/bilateral:66%/69%), reduced peak ankle plantar flexion moments (unilateral/bilateral:84%/83%), and reduced peak ankle power generation (unilateral/bilateral:67%/74%). Passive dorsiflexion was significantly correlated with peak dorsiflexion during stance and swing in both groups. Patients with unilateral compared to bilateral clubfoot showed decreased peak dorsiflexion and an associated knee flexor moment.

SIGNIFICANCE

Patients with recurrent clubfoot show gait deviations at the ankle that can be explained by joint level impairment and compensations at the knee, hip and pelvis. Patients with unilateral clubfoot typically show decreased dorsiflexion range of motion and associated greater gait impacts and compensations than bilateral clubfoot. Understanding the relationships between impairments and gait function and the implications of unilateral versus bilateral clubfoot will help improve prognostic ability and optimize future treatment outcomes.

Nwdps protocol - A simple functional outcome assessment tool for clubfoot correction and a review of literature

INTRODUCTION

Various clubfoot severity scoring systems are known to us. Dimeglio and Pirani Scoring systems are most widely used. Also, various treatment outcome measures have been proposed by researchers to assess patient satisfaction and results of treatment. None of the available methods are widely popular and amenable for routine use. A "nwdps protocol" was proposed for functional assessment of patients with clubfoot correction, where "n" was no pain during walking or running; "w" was ability to wear normal shoes; "d" was no significant difference in foot/shoe size of both sides; "p" was plantigrade foot and "s" was ability of the child to squat without heel lift-off. The aim of this study was to test this functional outcome assessment tool for easy day to day use post clubfoot correction.

METHODS

The nwdps protocol was applied to all the children at followup on a yearly basis who underwent clubfoot deformity correction in Department of Orthopaedics of our Institute between March 2016 and January 2018.

RESULTS

Eighty children were enrolled for the study, 45 had bilateral affection while 35 had unilateral affection. In all 125 feet were treated for clubfoot correction and evaluated using nwdps protocol. Each child was assessed by 2 researchers independently. There was no difference in functional assessment of 2 observers. Fifty-nine children were nwdp positive, one was nwps positive, while 2 were dwps positive at the end of 1 year. 79 children became nwdps positive at the end of 2nd year of followup.

CONCLUSION

Nwdps protocol is a very easy to remember and easy to use functional outcome assessment tool post clubfoot correction with high degree of objectivity and interobserver reliability.

LEVEL OF EVIDENCE

Level IV.

Can Repeated Ponseti Management for Relapsed Clubfeet Produce the Outcome Comparable With the Case Without Relapse? A Clinical Study in Term of Gait Analysis

BACKGROUND

The prevention and treatment of relapsed clubfoot remained challenging tasks. There were controversies as to treatment options and management, such as complete subtalar release, application of an Ilizarov external frame, or repeated Ponseti method; and different options were available in different treatment centers. This study was designed to evaluate the clinical outcome of relapsed clubfeet treated by repeated Ponseti method in comparison with the cases without relapse in term of gait analysis and to clarify the clinical efficacy of repeated Ponseti method in treating the relapsed clubfeet.

METHODS

Thirty-seven patients (53 feet) were retrospectively identified from our database according to the inclusion and exclusion criteria. Among the 37 patients, 17 cases (25 relapsed clubfeet) were assigned to group I, whereas 20 cases (28 clubfeet without relapse) were assigned to group II. Clinical examination, gait analysis, and kinematic gait deviation criteria from Texas Scottish Rite Hospital for Children were used for evaluation.

RESULTS

There was statistically significant difference in the parameters of foot length, stride length, and single limb support time (%gait cycle) between the 2 groups (P<0.05). No statistically significant difference was found in the kinematic parameters of total hip, knee, and ankle excursion, peak knee and ankle flexion and extension, and internal foot progression (P>0.05). There was no statistically significant difference in peak hip, knee, and ankle flexion moment, peak knee valgus moment, and peak ankle power (P>0.05). No statistically significant difference was found in equinus and calcaneus gait, increased ankle dorsiflexion, foot drop, and internal foot progression angle (P>0.05).

CONCLUSIONS

Repeated Ponseti method for relapsed clubfeet can yield good or excellent clinical results. We recommend repeated Ponseti method as the treatment choice for relapsed clubfeet in the early stage.

LEVEL OF EVIDENCE

Level III-retrospective comparative study.

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.

Functional Outcomes Following Treatment for Clubfoot: Ten-Year Follow-up

BACKGROUND

The purpose of this study was to assess function, at the age of 10 years, of children initially treated nonoperatively for clubfoot with either the Ponseti or French physiotherapy program and to compare outcomes in feet that had undergone only nonoperative treatment with those that required subsequent surgery.

METHODS

Gait analysis, isokinetic ankle strength, parent-reported outcomes, and daily step activity data were collected when patients who had been treated for idiopathic clubfoot reached the age of 10 years. Patients who had undergone only nonoperative treatment were compared with those who subsequently underwent extra-articular surgery or intra-articular surgery (posterior release or posteromedial release). The clubfoot groups were compared with age-matched controls.

RESULTS

Of 263 treated clubfeet in 175 patients, 148 had only been treated nonoperatively, 29 underwent extra-articular surgery, and 86 underwent intra-articular surgery (posterior release in 42 and posteromedial release in 44). Significant abnormalities were found in ankle kinetics and isokinetic ankle strength in the feet treated with intra-articular surgery compared with the nonoperatively treated feet (p < 0.017). Compared with controls (n = 40 feet), all groups showed reduced ankle plantar flexion during gait, resulting in a deficit of 9% to 14% for dynamic range of motion, 13% to 20% for ankle moment, and 13% to 23% for power (p < 0.013). Within the intra-articular group, feet that underwent posteromedial release had decreased plantar flexion strength (15%; p = 0.008), dorsiflexion strength (6%; p = 0.048), and parent-reported global function scores (p = 0.032) compared with the posterior release group. The patients with clubfoot took 10% fewer steps (p = 0.015) and had 11% less total ambulatory time (p = 0.001) than the controls.

CONCLUSIONS

Examination of patients when they had reached the age of 10 years showed better ankle power and isokinetic strength for clubfeet treated without surgery compared with those that underwent intra-articular surgery for residual deformity or recurrence. Compared with controls, both nonoperatively and surgically treated clubfeet had significant limitations in ankle plantar flexion resulting in decreased range of motion, moment, and power. Gastrocnemius-soleus complex strength was decreased after both nonoperative and surgical treatment of clubfeet. Although activity was diminished in the clubfoot population, no differences in function were perceived by the patients' parents.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Gait kinetics in children with clubfeet treated surgically or with the Ponseti method: A meta-analysis

BACKGROUND

Currently, the Ponseti method is the gold standard for treatment of clubfeet. For long-term functional evaluation of this method, gait analysis can be performed. Previous studies have assessed gait differences between Ponseti treated clubfeet and healthy controls.

RESEARCH QUESTION/PURPOSE

The aims of this systematic review were to compare the gait kinetics of Ponseti treated clubfeet with healthy controls and to compare the gait kinetics between clubfoot patients treated with the Ponseti method or surgically.

METHODS

A systematic search was performed in Embase, Medline Ovid, Web of Science, Scopus, Cochrane, Cinahl ebsco, and Google scholar, for studies reporting on gait kinetics in children with clubfeet treated with the Ponseti method. Studies were excluded if they only used EMG or pedobarography. Data were extracted and a risk of bias was assessed. Meta-analyses and qualitative analyses were performed.

RESULTS

Nine studies were included, of which five were included in the meta-analyses. The meta-analyses showed that ankle plantarflexor moment (95% CI -0.25 to -0.19) and ankle power (95% CI -0.89 to -0.60, were significantly lower in the Ponseti treated clubfeet compared to the healthy controls. No significant difference was found in ankle dorsiflexor and plantarflexor moment, and ankle power between clubfeet treated with surgery compared to the Ponseti method.

SIGNIFICANCE

Differences in gait kinetics are present when comparing Ponseti treated clubfeet with healthy controls. However, there is no significant difference between surgically and Ponseti treated clubfeet. These results give more insight in the possibilities of improving the gait pattern of patients treated for clubfeet.

Biomechanical Evaluation of Circumtibial and Transmembranous Routes for Posterior Tibial Tendon Transfer for Dropfoot

BACKGROUND

Tibialis posterior tendon transfer is performed when loss of dorsiflexion has to be compensated. We evaluated the circumtibial (CT), above-retinaculum transmembranous (TMAR), and under-retinaculum transmembranous (TMUR) transfer gliding resistance and foot kinematics in a cadaveric foot model during ankle range of motion (ROM).

METHODS

Eight cadaveric foot-ankle distal tibia specimens were dissected free of soft tissues on the proximal end, applying an equivalent force to 50% of the stance phase to every tendon, except for the Achilles tendon. Dorsiflexion was tested with all of the tibialis posterior tendon transfer methods (CT, TMAR, and TMUR) using a tension tensile machine. A 10-repetition cycle of dorsiflexion and plantarflexion was performed for each transfer. Foot motion and the force needed to achieve dorsiflexion were recorded.

RESULTS

The CT transfer showed the highest gliding resistance ( P < .01). Regarding kinematics, all transfers decreased ankle ROM, with the CT transfer being the condition with less dorsiflexion compared with the control group (6.8 vs 15 degrees, P < .05). TMUR transfer did perform better than TMAR with regard to ankle dorsiflexion, but no difference was shown in gliding resistance. The CT produced a supination moment on the forefoot.

CONCLUSION

The CT transfer had the highest tendon gliding resistance, achieved less dorsiflexion and had a supination moment. Clinical Relevance We suggest that the transmembranous tibialis posterior tendon transfer should be the transfer of choice. The potential bowstringing effect when performing a tibialis posterior tendon transfer subcutaneously (TMAR) could be avoided if the transfer is routed under the retinaculum, without significant compromise of the final function and even with a possible better ankle range of motion.

Repeatability of the Oxford Foot Model in children with foot deformity

INTRODUCTION

The Oxford Foot Model (OFM) is a multi-segment, kinematic model developed to assess foot motion. It has previously been assessed for repeatability in healthy populations. To determine the OFM's reliability for detecting foot deformity, it is important to know repeatability in pathological conditions. The aim of the study was to assess the repeatability of the OFM in children with foot deformity.

METHODS

Intra-tester repeatability was assessed for 45 children (15 typically developing, 15 hemiplegic, 15 clubfoot). Inter-tester repeatability was assessed in the clubfoot population. The mean absolute differences between testers (clubfoot) and sessions (clubfoot and hemiplegic) were calculated for each of 15 clinically relevant, kinematic variables and compared to typically developing children.

RESULTS

Children with clubfoot showed a mean difference between visits of 2.9° and a mean difference between raters of 3.6° Mean absolute differences were within one degree for the intra and inter-rater reliability in 12/15 variables. Hindfoot rotation, forefoot/tibia abduction and forefoot supination were the most variable between testers. Overall the clubfoot data were less variable than the typically developing population. Children with hemiplegia demonstrated slightly higher differences between sessions (mean 4.1°), with the most reliable data in the sagittal plane, and largest differences in the transverse plane.

CONCLUSIONS

The OFM was designed to measure different types of foot deformity. The results of this study show that it provides repeatable results in children with foot deformity. To be distinguished from measurement artifact, changes in foot kinematics as a result of intervention or natural progression over time must be greater than the repeatability reported here.

Ponseti method is superior to surgical treatment in clubfoot - Long-term, randomized, prospective trial

Treatment of idiopathic clubfoot has shifted from extensive surgical release to conservative Ponseti method; however, randomized prospective trials to compare both methods are lacking. The goal of this study was to compare the long-term results of Ponseti method with those of surgery in terms of morphology, function, X-rays, overall health and gait. In 2001, a single center, prospective, randomized, and controlled trial with a parallel design was started. Twenty-four feet of 15 patients were randomly assigned to two groups: 12 feet each to a Ponseti and surgical group. Mean follow-up was 10 years. International Clubfoot Study Group score (ICFSG), the Pediatric Outcomes Data Collection Instrument (PODCI) and the Functional Rating System (FRS) were used to compare morphology, functional, radiological and subjective outcomes, and the Oxford Foot Model (OFM) was used to evaluate foot kinematics. No significant difference was seen between groups in the initial Pirani scores (p=0.618). Ponseti group had more favorable long-term outcomes according to the FRS (p=0.005), higher ICFSG, scores for morphology (p=0.021), function (p=0.005) and X-rays (p=0.02), and better parent reported functional status according to the PODCI (p=0.018). Surgically treated clubfeet were stiffer - ankle dynamic range of motion (p=0.015) and the maximal hindfoot dorsiflexion during gait were limited as measured by OFM (p=0.039). This was compensated by an increase in motion between the hindfoot and forefoot. Furthermore, these children had more difficulty playing sports and experienced more pain, which might have led to inferior results in the happiness domain of the PODCI. These results suggest that the Ponseti method provides superior long-term outcomes for idiopathic clubfoot deformity.

Effects of different medial arch support heights on rearfoot kinematics

Background

Foot orthoses are usually assumed to be effective by optimizing mechanically dynamic rearfoot configuration. However, the effect from a foot orthosis on kinematics that has been demonstrated scientifically has only been marginal. The aim of this study was to examine the effect of different heights in medial arch-supported foot orthoses on rear foot motion during gait.

Methods

Nineteen asymptomatic runners (36±11years, 180±5cm, 79±10kg; 41±22km/week) participated in the study. Trials were recorded at 3.1 mph (5 km/h) on a treadmill. Athletes walked barefoot and with 4 different not customized medial arch-supported foot orthoses of various arch heights (N:0 mm, M:30 mm, H:35 mm, E:40mm). Six infrared cameras and the `Oxford Foot Model´ were used to capture motion. The average stride in each condition was calculated from 50 gait cycles per condition. Eversion excursion and internal tibia rotation were analyzed. Descriptive statistics included calculating the mean ± SD and 95% CIs. Group differences by condition were analyzed by one factor (foot orthoses) repeated measures ANOVA (α = 0.05).

Results

Eversion excursion revealed the lowest values for N and highest for H (B:4.6°±2.2°; 95% CI [3.1;6.2]/N:4.0°±1.7°; [2.9;5.2]/M:5.2°±2.6°; [3.6;6.8]/H:6.2°±3.3°; [4.0;8.5]/E:5.1°±3.5°; [2.8;7.5]) (p>0.05). Range of internal tibia rotation was lowest with orthosis H and highest with E (B:13.3°±3.2°; 95% CI [11.0;15.6]/N:14.5°±7.2°; [9.2;19.6]/M:13.8°±5.0°; [10.8;16.8]/H:12.3°±4.3°; [9.0;15.6]/E:14.9°±5.0°; [11.5;18.3]) (p>0.05). Differences between conditions were small and the intrasubject variation high.

Conclusion

Our results indicate that different arch support heights have no systematic effect on eversion excursion or the range of internal tibia rotation and therefore might not exert a crucial influence on rear foot alignment during gait.

Functional Assessment of the Foot Undergoing Percutaneous Achilles Tenotomy in Term of Gait Analysis

Background. This study was designed to evaluate the function of the foot undergoing the procedure of percutaneous Achilles tenotomy (PAT) in case of clubfoot management in terms of gait analysis. Methods. Nineteen patients with unilateral clubfeet were retrospectively reviewed from our database from July 2012 to June 2016. The result in all the cases was rated as excellent according to the scale of International Clubfoot Study Group (ICSG). The affected sides were taken as Group CF and the contralateral sides as Group CL. Three-dimensional gait analysis was applied for the functional evaluation of the involved foot. Results. Statistical difference was found in physical parameters of passive ankle dorsiflexion and plantar-flexion. No statistical difference was found in temporal-spatial parameters. There was statistical difference in kinematic parameters of total ankle rotation, ankle range of motion, and internal foot progression angle and in kinetic parameters of peak ankle power. No statistical difference was found in other kinematic and kinetic parameters. Conclusions. It is demonstrated that the procedure of PAT is safe and efficient for correcting the equinus deformity in case of clubfoot management and preserving the main function of Achilles tendon at the minimum of four-year follow-up.

Dynamic Adduction Angle of Forefoot Measured With a Novel Technique And Its Relationship With Functional Outcomes

BACKGROUND

Idiopathic clubfoot is commonly treated with the Ponseti method with the extent of invasive treatment involving tendon-Achilles lengthening. Forefoot adduction is a common complication in surgically treated clubfeet. Yet, no method has been described to measure dynamic (walking) forefoot adduction. The aim of this study was to assess the persistent pes adductus in children whose clubfeet were surgically treated using a dorsomedial soft tissue release and to find out correlations between forefoot adduction and clinical outcome measures.

METHODS

We analysed the dynamic adduction angle in 33 clubfeet using a pressure-sensitive foot platform and compared it to the healthy feet of an age- and weight-matched group of children without congenital foot deformities. The clinical outcome was analysed using the McKay score.

RESULTS

Mean dynamic adduction angle was 4.1o in the surgically corrected clubfeet, whereas it was 6.4° in unaffected feet of patients with unilateral clubfoot and 7.1o in control group. The McKay score were excellent in 1 patient, good in 5, average in 13, and fair in 4 of the 23 patients. There was no correlation between dynamic adduction angle and McKay score using paired t test (P > 0.05).

CONCLUSION

High occurrence of dynamic adduction angle in surgically treated clubfeet was detected. In conclusion, no correlation between forefoot adduction, dynamic forefoot adduction angle and clinical outcome measures within the study was observed.

Sensitivity of the Oxford Foot Model to marker misplacement: A systematic single-case investigation

The purpose of this paper was to systematically assess the effect of Oxford Foot Model (OFM) marker misplacement on hindfoot relative to tibia, and forefoot relative to hindfoot kinematic calculations during the stance phase of gait. Marker trajectories were recorded with an 8-camera motion analysis system (Vicon Motion Systems Ltd., UK) and ground reaction forces were recorded from three force platforms (AMTI, USA). A custom built marker cluster consisting of 4 markers in a square arrangement (diagonal distance 2 cm) was used to assess the effect of marker misplacement in the superior, inferior, anterior and posterior direction for the sustentaculum tali (STL), the proximal 1st metatarsal (P1M), distal 5th metatarsal (D5M), proximal 5th metatarsal (P5M) and lateral calcaneus (LCA) markers. In addition manual movement of the heel complex 1 cm superiorly, inferiorly, medially and laterally, and also an alignment error of 10° inversion and 10° eversion was assessed. Clinically meaningful effects of marker misplacement were determined using a threshold indicating the minimal clinically important difference. Misplacement of the heel-wand complex had the most pronounced effect on mean kinematic profiles during the stance phase across all degrees-of-freedom with respect to hindfoot-tibia and forefoot-hindfoot angles. Vertical marker misplacement of the D5M and P5M markers affected the sagittal plane, and to a lesser extent frontal plane, forefoot-hindfoot kinematics. In conclusion, the OFM is highly sensitive to misplacement of the heel-wand complex in all directions and the P5M marker in the vertical direction.

Pathophysiology of juvenile idiopathic arthritis induced pes planovalgus in static and walking condition: a functional view using 3D gait analysis

BACKGROUND

Patients suffering from juvenile idiopathic arthritis (JIA) frequently have affected ankle joints, which can lead to foot deformities such as pes planovalgus (JIA-PPV). Usually, JIA-PPV is diagnosed by examining the foot in non-weightbearing or in weightbearing, static condition. However, functional limitations typically appear during dynamic use in daily activities such as walking. The aim of this study was to quantify the pathophysiology of JIA-PPV in both static and dynamic condition, i.e. in upright standing and during the stance phase of walking using three-dimensional (3d) gait analysis.

METHODS

Eleven JIA patients (age = 12y) with at least one affected ankle joint and fixed pes planovalgus (≥5°) were compared to healthy controls (CG) (n = 14, age = 11y). Kinematic and kinetic data were obtained in barefoot standing and walking condition (1.1-1.3 m/s) with an 8-camera 3d motion analysis system including two force-plates and one pressure distribution plate. All participants were prepared using reflecting markers according to the Oxford Foot and Plug-in-Gait Model. Results were compared using the Mann-Whitney-U-test and Wilcoxon signed-rank test (p < 0.05).

RESULTS

In comparison to CG, JIA-PPV had an excessive hindfoot/tibia eversion (p < 0.001) and a forefoot/hindfoot supination (p < 0.001) in both static and walking condition. JIA-PPV showed a greater hindfoot/tibia eversion during walking (midstance) compared to standing (p = 0.021) in contrast to CG. The arch index, measured by plantar pressure distribution, indicates a reduced arch height in JIA-PPV (p = 0.007). Patients had a lower maximum dorsiflexion of hindfoot/tibia (p = 0.001) and a lower plantarflexion of forefoot/hindfoot (p = 0.028), both when standing and walking. The kinetic results showed lower maximum ankle dorsiflexion moments (p < 0.037) as well as generated ankle power (p = 0.086) in JIA-PPV.

CONCLUSIONS

The pathophysiology of JIA-PPV during walking indicated that excessive hindfoot eversion produces accessory symptoms such as a reduced arch height, increased forefoot supination and reduced propulsion effect of the ankle. Muscular and coordinative insufficiency caused by arthritis can lead to the observed increased hindfoot eversion from static to dynamic condition. Conventional static or passive foot examination techniques probably underestimate deformity in JIA pes planovalgus. 3d gait analysis might be helpful in early diagnosis of this condition, especially in JIA patients with affected ankle joints.

Results of gait analysis including the Oxford foot model in children with clubfoot treated with the Ponseti method

BACKGROUND

The aim of the study was to evaluate how clubfeet treated with the Ponseti method compare with control feet in gait analysis and whether additional information can be provided by the Oxford foot model.

METHODS

All patients with a minimum age of three years in our prospective database of clubfeet treated with the Ponseti method were considered for inclusion. Exclusion criteria were an associated syndrome or neurological disease, positional (slight) clubfoot, and presentation at an age of more than three months. Of the 125 patients with 199 clubfeet who satisfied the criteria, thirty-six (29%) agreed to participate in the study. Four of these were excluded because of insufficient gait analysis data, leaving thirty-two patients with fifty clubfeet for evaluation. Clinical examination and three-dimensional gait analysis including the Oxford foot model were performed, and a disease-specific questionnaire was administered. Kinetic and kinematic results were compared with those of an age-matched control group (n = 15).

RESULTS

The mean score on the disease-specific questionnaire was 83.5. Gait analysis showed significantly decreased range of motion, plantar flexion, and power of the ankle compared with controls. The mean external foot progression angle of 5.7° in the Ponseti group was slightly less than that in the controls. Slight intoeing occurred in 24%, and 12% did not achieve a neutral position during swing phase. Slight compensation was observed, including external rotation of the hip in 28%. The Oxford foot model revealed differences in foot motion between the groups.

CONCLUSIONS

Clubfoot treatment with the Ponseti method yielded good clinical results with high functional scores. Three-dimensional gait analysis demonstrated distinctive but slight deviations. Intoeing was less frequent and less severe compared with groups in the literature. We recommend the use of three-dimensional gait analysis, including a foot model, as an objective tool for evaluation of the results of clubfoot treatment.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

A portable system for foot biomechanical analysis during gait

Modeling the foot is challenging due to its complex structure compared to most other body segments. To analyze the biomechanics of the foot, portable devices have been designed to allow measurement of temporal, spatial, and pedobarographic parameters. The goal of this study was to design and evaluate a portable system for kinematic and dynamic analysis of the foot during gait. This device consisted of a force plate synchronized with four cameras and integrated into a walkway. The complete system can be packaged for transportation. First, the measurement system was assessed using reference objects to evaluate accuracy and precision. Second, nine healthy participants were assessed during gait trials using both the portable and Vicon systems (coupled with a force plate). The ankle and metatarsophalangeal (MP) joint angles and moments were computed, as well as the ground reaction force (GRF). The intra- and inter-subject variability was analyzed for both systems, as well as the inter-system variation. The accuracy and precision were, respectively 0.4 mm and 0.4 mm for linear values and 0.5° and 0.6° for angular values. The variability of the portable and Vicon systems were similar (i.e., the inter-system variability never exceeded 2.1°, 0.081 Nmkg(-1) and 0.267 Nkg(-1) for the angles, moments and GRF, respectively). The inter-system differences were less than the inter-subject variability and similar to the intra-subject variability. Consequently, the portable system was considered satisfactory for biomechanical analysis of the foot, outside of a motion analysis laboratory.

Long-term results of comprehensive clubfoot release versus the Ponseti method: which is better?

BACKGROUND

Clubfoot can be treated nonoperatively, most commonly using a Ponseti approach, or surgically, most often with a comprehensive clubfoot release. Little is known about how these approaches compare with one another at longer term, or how patients treated with these approaches differ in terms of foot function, foot biomechanics, or quality-of-life from individuals who did not have clubfoot as a child.

QUESTIONS/PURPOSES

We compared (1) focused physical and radiographic examinations, (2) gait analysis, and (3) quality-of-life measures at long-term followup between groups of adult patients with clubfoot treated either with the Ponseti method of nonsurgical management or a comprehensive surgical release through a Cincinnati incision, and compared these two groups with a control group without clubfoot.

METHODS

This was a case control study of individuals treated for clubfoot at two separate institutions with different methods of treatment between 1983 to 1987. One hospital used only the Ponseti method and the other mainly used a comprehensive clubfoot release. There were 42 adults (24 treated surgically, 18 treated with Ponseti method) with isolated clubfoot along with 48 healthy control subjects who agreed to participate in a detailed analysis of physical function, foot biomechanics, and quality-of-life metrics.

RESULTS

Both treatment groups had diminished strength and motion compared with the control subjects on physical examination measures; however, the Ponseti group had significantly greater ankle plantar flexion ROM (p < 0.001), greater ankle plantar flexor (p = 0.031) and evertor (p = 0.012) strength, and a decreased incidence of osteoarthritis in the ankle and foot compared with the surgical group. During gait the surgical group had reduced peak ankle plantar flexion (p = 0.002), and reduced sagittal plane hindfoot (p = 0.009) and forefoot (p = 0.008) ROM during the preswing phase compared with the Ponseti group. The surgical group had the lowest overall ankle power generation during push off compared with the control subjects (p = 0.002). Outcome tools revealed elevated pain levels in the surgical group compared with the Ponseti group (p = 0.008) and lower scores for physical function and quality-of-life for both clubfoot groups compared with age-range matched control subjects (p = 0.01).

CONCLUSIONS

Although individuals in each treatment group experienced pain, weakness, and reduced ROM, they were highly functional into early adulthood. As adults the Ponseti group fared better than the surgically treated group because of advantages including increased ROM observed at the physical examination and during gait, greater strength, and less arthritis. This study supports efforts to correct clubfoot with Ponseti casting and minimizing surgery to the joints, and highlights the need to improve methods that promote ROM and strength which are important for adult function.

LEVEL OF EVIDENCE

Level III, prognostic study.

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.

Surgical versus Ponseti approach for the management of CTEV: a comparative study

BACKGROUND

Results from a comparative study of Ponseti versus surgical management for congenital talipes equino varus (CTEV), using historically managed patients, are presented. No bias existed in terms of management choice or participants recruited.

METHODS

Twenty-three surgically treated children (31 club feet; mean age 9.1 y) and 29 treated by the Ponseti technique (42 club feet; mean age 6.5 y) agreed to participate in the study. Twenty-six typically developing children (mean age 7.9 y) were also recruited as a control group. A physical examination and 3-dimensional gait analyses were carried out on all participants, and each child and his/her parent also, independently, completed the Oxford Ankle Foot Questionnaire (OxAFQ).

RESULTS

The Ponseti group underwent fewer joint-invasive procedures than the surgical group. Passive range of dorsiflexion and plantarflexion were significantly less in the CTEV groups when compared with the control group (P<0.001), and plantarflexion was also significantly less in the surgical than in the Ponseti group (P<0.05). The bimalleolar axis was found to be significantly less in the CTEV groups than in the control group (P<0.001) and also significantly less in the surgical than in the Ponseti group (P<0.05). The gait deviation index, a gait score based on kinematics, showed a more normal gait pattern in the Ponseti group compared with the surgical group (P<0.001). The CTEV groups did not differ significantly from each other in terms of ankle sagittal and transverse plane kinematics or kinetics, but foot progression angle for the Ponseti group was external, whereas that for the surgical group was internal. The Ponseti group also scored higher than the surgical group in terms of patient satisfaction, with significantly better parent-rated OxAFQ scores in the "emotional" and "school and play" domains.

CONCLUSIONS

The adoption of the Ponseti technique has resulted in fewer and less-invasive operations for our CTEV population, with accompanying improvement in the overall gait pattern (gait deviation index) and parent satisfaction (OxAFQ).

LEVEL OF EVIDENCE

Level III.

Segmental motion of forefoot and hindfoot as a diagnostic tool

Segmental motions derived from non-invasive motion analysis are being used to investigate the intrinsic functional behavior of the foot and ankle in health and disease. The goal of this research was to examine the ability of a generic segmented model of the foot to capture and differentiate changes in internal skeletal kinematics due to neuromuscular disease and/or trauma. A robotic apparatus that reproduces the kinematics and kinetics of gait in cadaver lower extremities was employed to produce motion under normal and aberrant neuromuscular activation patterns of tibialis posterior and/or tibialis anterior. Stance phase simulations were conducted on 10 donor limbs while recording three-dimensional kinematic trajectories of (1) skin-mounted markers used clinically to construct segmented foot models, and (2) bone-mounted marker clusters to capture actual internal bone motion as the gold standard for comparison. The models constructed from external marker data were able to differentiate the kinematic behaviors elicited by different neuromuscular conditions in a manner similar to that using the bone-derived data. Measurable differences between internal and externally measured kinematics were small, variable and random across the three axes of rotation and neuromuscular conditions, with a tendency toward more differences noted during early and late stance. Albeit slightly different, three-dimensional motion profiles of the hindfoot and forefoot segments correlated well with internal skeletal motion under all neuromuscular conditions, thereby confirming the utility of measuring segmental motions as a valid means of clinical assessment.

Secondary gait deviations in patients with and without neurological involvement: a systematic review

Pathologies that lead to biomechanical restrictions in human gait interfere with the tightly regulated muscle activation patterns that control the external moments. In order to maintain proper function, secondary mechanisms are required. The aims of this systematic review were (1) to identify secondary mechanisms in pathologic gait that have been described throughout the scientific literature by means of instrumented gait analysis, (2) to distinguish between active compensatory mechanisms and passive physical effects and (3) to identify common compensatory mechanisms that appear to be independent from the underlying disease. A comprehensive literature search revealed 4080 citations for review, whereof 148 studies entered the full-text review. Thirty-six studies were included and the quality of these studies was assessed by two independent reviewers (kappa=0.83). The quality of the included studies showed large variation and several methodological issues were identified. Five studies were further identified describing only passive physical effects, leaving a total of 31 studies reporting on compensations. The qualitative analysis revealed common compensations that appeared to be independent from the underlying pathology. In clinical practice, distinguishing primary from secondary gait deviations can be considered highly important since unnecessary treatment may be avoided. However, given the introduction of general principles of compensatory mechanisms and the fact that certain presumed "compensations" were identified as simple passive physical effects, secondary gait deviations have to be further investigated. Computer simulation studies are valuable, especially in respect of the distinction between compensations and physical effects. Furthermore, the need for a uniform terminology was highlighted.

Desenvolvimento de um modelo de pé segmentado para avaliação de indivíduos calçados

INTRODUÇÃO: O uso de calçados pode influenciar parâmetros cinemáticos dos segmentos do pé durante a marcha. OBJETIVO: Testar um modelo biomecânico para avaliar o deslocamento angular dos segmentos do pé durante a marcha de indivíduos calçados. MATERIAIS E MÉTODOS: Dez indivíduos adultos jovens saudáveis participaram do estudo. Um par de tênis foi utilizado durante o estudo. O sistema Qualisys Pró-Reflex foi utilizado para a avaliação das variáveis de desfecho: deslocamento angular de retropé nos planos sagital, frontal e transverso e de antepé nos planos frontal e transverso. O Coeficiente de Correlação Intraclasse foi usado para verificar o grau de associação das seguintes variáveis entre as duas visitas: valores angulares máximos e mínimos e deslocamento angular total. RESULTADOS: As variáveis de desfecho apresentaram confiabilidade teste-reteste de moderada a excelente. DISCUSSÃO: O nível de confiabilidade encontrado foi considerado aceitável, fornecendo, assim, uma base sólida para a avaliação objetiva da cinemática dos segmentos do pé de indivíduos calçados em ambientes laboratoriais, para fins de pesquisas científicas e avaliações clínicas da cinemática da marcha humana. CONCLUSÃO: A qualidade do método desenvolvido e da análise de confiabilidade realizada detectou padrões de movimento dos segmentos do pé próximos aos descritos na literatura. Além disso, o protocolo de aquisição apresentado não é invasivo, não requer uma estrutura extra de referência, posicionamento da articulação subtalar em neutro nem é dependente da informação fornecida por raios-X.

Use of the Ponseti method in the Iranian population

BACKGROUND

The most common congenital orthopaedic condition requiring treatment is clubfoot. The Ponseti method, which has improved the recurrence rate, is at present the most attractive method of treatment in the north of America. The purpose of this study was to evaluate the outcome of this method in an Iranian population and look for characteristics that may affect the treatment process.

METHODS

A total of 78 patients (129 feet) were treated by precisely adhering to the technique originally introduced by Ponseti. Relapse was defined as any return of each of 4 clubfoot components according to the Dimeglio-Bensahel system. The mean follow-up period was 24.7 months and relapse was analyzed with respect to severity of primary disorder, number of casts, compliance with postcorrection bracing and stretching exercise, and educational level of parents.

RESULTS

At the end of the follow-up, 24 (18.6%) clubfeet experienced relapse as defined. The mean time to relapse was 13.7 months, 30 feet had brace noncompliance, and stretching was not done for 35 feet. Significant association was detected between recurrence and severity of clubfoot, number of casts for complete correction, and bracing and stretching exercise noncompliance.

CONCLUSIONS

The Ponseti method is a successful treatment protocol for idiopathic clubfoot. Its success rate will increase with use of abduction orthosis after complete correction and also by performing regular stretching exercises.

LEVEL OF EVIDENCE

Therapeutic level II.

Analysis of a kinetic multi-segment foot model. Part I: Model repeatability and kinematic validity

Kinematic multi-segment foot models are still evolving, but have seen increased use in clinical and research settings. The addition of kinetics may increase knowledge of foot and ankle function as well as influence multi-segment foot model evolution; however, previous kinetic models are too complex for clinical use. In this study we present a three-segment kinetic foot model and thorough evaluation of model performance during normal gait. In this first of two companion papers, model reference frames and joint centers are analyzed for repeatability, joint translations are measured, segment rigidity characterized, and sample joint angles presented. Within-tester and between-tester repeatability were first assessed using 10 healthy pediatric participants, while kinematic parameters were subsequently measured on 17 additional healthy pediatric participants. Repeatability errors were generally low for all sagittal plane measures as well as transverse plane Hindfoot and Forefoot segments (median<3°), while the least repeatable orientations were the Hindfoot coronal plane and Hallux transverse plane. Joint translations were generally less than 2mm in any one direction, while segment rigidity analysis suggested rigid body behavior for the Shank and Hindfoot, with the Forefoot violating the rigid body assumptions in terminal stance/pre-swing. Joint excursions were consistent with previously published studies.

A clinically applicable six-segmented foot model

We describe a multi-segmented foot model comprising lower leg, rearfoot, midfoot, lateral forefoot, medial forefoot, and hallux for routine use in a clinical setting. The Ghent Foot Model describes the kinematic patterns of functional units of the foot, especially the midfoot, to investigate patient populations where midfoot deformation or dysfunction is an important feature, for example, rheumatoid arthritis patients. Data were obtained from surface markers by a 6 camera motion capture system at 500 Hz. Ten healthy subjects walked barefoot along a 12 m walkway at self-selected speed. Joint angles (rearfoot to shank, midfoot to rearfoot, lateral and medial forefoot to midfoot, and hallux to medial forefoot) in the sagittal, frontal, and transverse plane are reported according to anatomically based reference frames. These angles were calculated and reported during the foot rollover phases in stance, detected by synchronized plantar pressure measurements. Repeated measurements of each subject revealed low intra-subject variability, varying between 0.7° and 2.3° for the minimum values, between 0.5° and 2.1° for the maximum values, and between 0.8° and 5.8° for the ROM. The described movement patterns were repeatable and consistent with biomechanical and clinical knowledge. As such, the Ghent Foot model permits intersegment, in vivo motion measurement of the foot, which is crucial for both clinical and research applications.

A comprehensive outcome comparison of surgical and Ponseti clubfoot treatments with reference to pediatric norms

PURPOSE

Isolated congenital clubfoot can be treated either operatively (posteromedial release) or conservatively (Ponseti method). This study retrospectively compared mid-term outcomes after surgical and Ponseti treatments to a normal sample and used multiple evaluation techniques, such as detailed gait analysis and foot kinematics.

METHODS

Twenty-six children with clubfoot treated surgically and 22 children with clubfoot treated with the Ponseti technique were evaluated retrospectively and compared to 34 children with normal feet. Comprehensive evaluation included a full gait analysis with multi-segment and single-segment foot kinematics, pedobarograph, physical examination, validated outcome questionnaires, and radiographic measurements.

RESULTS

The Ponseti group had significantly better plantarflexion and dorsiflexion range of motion during gait and had greater push-off power. Residual varus was present in both treatment groups, but more so in the operative group. Gait analysis also showed that the operative group had residual in-toeing, which appeared well corrected in the Ponseti group. Pedobarograph results showed that the operative group had significantly increased varus and significantly decreased medial foot pressure. The physical examination demonstrated significantly greater stiffness in the operative group in dorsiflexion, plantarflexion, ankle inversion, and midfoot abduction and adduction. Surveys showed that the Ponseti group had significantly more normal pediatric outcome data collection instrument results, disease-specific indices, and Dimeglio scores. The radiographic results suggested greater equinus and cavus and increased foot internal rotation profile in the operative group compared with the Ponseti group.

CONCLUSIONS

Ponseti treatment provides superior outcome to posteromedial release surgery, but residual deformity still persists.

Tibiofibular torsion in congenital clubfoot

Tibiofibular torsion was measured by computed tomography in three series of patients affected by congenital clubfoot who were treated with different protocols. The normal leg of unilateral deformities served as the control. For the bilateral cases, only the right side was included in the study. The angle between the bicondylar axis of the tibia and the bimalleolar axis was the index of tibiofibular torsion. There were 34 clubfeet in the first series, treated with a posteromedial release, and 40 clubfeet in the second series, treated with a modified Ponseti method, whereas the third series included 16 clubfeet, treated with the original Ponseti method. All 90 clubfeet were graded at birth as group 3 according to the Manes classification. No patient had previous treatment. The patients of the first and the second series were followed up to maturity, whereas the patients of the third series were followed up to a maximum of 11 years of age. In the congenital clubfoot, the tibia and the fibula were externally rotated, in comparison with the normal leg; in fact, the average value of the angle of tibiofibular torsion was 32.2° in the first series, 23.9° in the second series, and 21.1° in the third series. In the normal tibiae, the average value of the angle of tibiofibular torsion was 21.4°. The difference between the first series and the normal controls was statistically significant, as was the difference between the first one and the other two series. The value of the tibiofibular torsion angle seems to be related to the manipulation technique used to treat clubfoot: when the manipulation does not allow a progressive eversion of the talus underneath the calcaneus, the external tibial torsion increases. At follow-up, an intoeing gait was present in seven treated clubfeet of the first series. In all of them except one, the highest value of the external tibial torsion angle was observed, with a low value of the Kite's angle and/or residual forefoot adduction. In the treated congenital clubfoot, persistent intoeing is not related to the angle of tibial torsion but rather to the amount of correction of calcaneal inversion and residual forefoot adduction.

Comprehensive review of the functional outcome evaluation of clubfoot treatment: a preferred methodology

Treatment outcome has been a focus of interest in those who manage clubfeet. Because of a lack of a common evaluation protocol, it has become necessary to establish a universally recognized quantitative measurement to compare and better understand the treatment outcome. The outcome is not merely morphological and radiographic, but it should also include functional and quality-of-life measurements. In this article, we will outline the most commonly used methods of long-term evaluation for congenital clubfeet and recommend the data collection parameters that are most appropriate for a comprehensive functional analysis. This will begin with pretreatment classifications that are important in prognosticating the results. The physical examinations and plain radiographs in standing position are also two fundamental evaluations of clubfoot. Several outcome evaluations have been published in the literature and may be useful depending on the desired metrics. Gait analysis is an additional useful technical tool for analyzing the motion of the foot and ankle and its relation to the whole body function; pedobarography added to the dynamics of the evaluation. Functional quality-of-life questionnaires are increasing in popularity for measuring the total body functional status and the quality of life.

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.

The effects of surface slope on multi-segment foot kinematics in healthy adults

Previous work evaluating the effects of surface slope on gait has focused on lower extremity kinematics and kinetics. However, an assessment of multi-segment foot kinematics during walking on inclined and declined ramps has not been previously reported. Sagittal ankle motion using a single rigid body foot model and three-dimensional hindfoot and forefoot kinematics for 24 healthy adults (16 females and 8 males, average age 25.5 ± 4.4 years) were compared during level surface, inclined surfaces of 3%, 6%, 9% and 12% grade and a declined surface of approximately 7.5% grade at a constant speed using a standard treadmill. Significant differences in peak hindfoot plantarflexion, sagittal plane range of motion and time of peak dorsiflexion, plantarflexion, varus and valgus were seen between surface slope conditions. Significant changes were also seen in forefoot plantarflexion and sagittal plane range of motion however the maximum difference between conditions was less than 3°. These results indicate that foot mechanics can be significantly altered when ambulating on ramps in healthy adults. Specifically, treadmill protocols which incorporate different surface slopes often encountered during ambulation of daily living, may provide an improved technique in evaluating a patient's ability to function in the community.

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

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

Long-term outcome evaluation in young adults following clubfoot surgical release

BACKGROUND

The aim of this study was to evaluate the long-term outcome of a comprehensive surgical release for congenital talipes equinovarus (CTEV).

METHODS

Gait, strength, segmental foot motion, and outcomes questionnaire data were collected on 24 adults (21.8+/-2.3 y) who were surgically treated for CTEV as infants. These data were statistically compared with of 48-age group matched controls (23.2+/-2.4 y).

RESULTS

The clubfoot group was functional in activities of daily living, although most patients did experience foot pain after a day of typical activities, such as walking, standing, using stairs and doing exercise. Lower extremity gait kinematics was similar to the control group. There were differences in segmental foot motion with the hindfoot in a more plantarflexed position relative to the tibia and the forefoot dorsiflexed, and adducted relative to the hindfoot. Ankle plantarflexion and inversion strength and range of motion was reduced in the clubfoot group in association with an increase in hip power generation during the preswing and initial swing phases of the gait cycle.

CONCLUSIONS

Surgical correction of CTEV was successful in providing a functional plantigrade foot as the patients reached adulthood. However, limitations included foot pain, limited foot range of motion, and weakness.

LEVEL OF EVIDENCE

Level III.

A comparison of multi-segment foot kinematics during level overground and treadmill walking

Previous work comparing treadmill and overground walking has focused on lower extremity motion and kinetics, with few identified differences. However, a comparison of multi-segment foot kinematics between these conditions has not been previously reported. Sagittal ankle motion using a single rigid body foot model and three-dimensional hindfoot and forefoot kinematics were compared during barefoot, level, overground walking at a self-selected speed and treadmill walking at a similar speed for 20 healthy adults. Slight differences were seen in ankle plantarflexion and hindfoot plantarflexion during first rocker, as well as peak forefoot eversion and abduction, however all changes were less than 3 degrees , and most were within the day-to-day repeatability. These results indicate that foot mechanics as determined using a multi-segment foot model were similar between overground and treadmill walking at similar speeds in healthy adults. Treadmill protocols may provide a controlled method to analyze a patient's ability to adapt to walking at different speeds and surface slopes, which are encountered often during ambulation of daily living.

The recurrent clubfoot: can gait analysis help us make better preoperative decisions?

Gait patterns in children with recurrent clubfoot are often associated with more or less subtle factors contributing to the patterns, such as tibial torsion that might not be detected by visual observation and therefore not considered in a treatment plan. We therefore used gait analysis to elucidate the contributions to recurrent clubfoot deformity and to determine whether gait analysis could be important in preoperative decision-making for these patients. We reviewed all 35 patients (56 feet) referred to our gait laboratory for recurrent deformity following treatment of idiopathic clubfoot. The average age of the children in our series was 6.7 years (range, 3.6-15.4 years). Data were acquired from computerized motion analysis, dynamic electromyography, and static measurements by a physical therapist. We found a high incidence of transverse plane deformities including intoeing in 45 of 56 feet (80%), internal tibial torsion in 40 of 56 feet (71%), and forefoot adductus in 40 of 56 feet (71%). Forty feet were supinated in stance; of these patients, 28 (70%) had overactive tibialis anterior muscle activity based on dynamic EMG. Dynamic compensatory hip external rotation was present in 28 of 56 (50%) of limbs. Thirty of the 35 patients underwent surgery following gait analysis; the most common procedures included split anterior tibial tendon transfers (34), tibial derotational osteotomies (34), and midfoot osteotomies (20). Quantitative gait analysis resulted in 28 changed procedures in 19 of 30 patients (63%) compared to prestudy surgical plans.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Gait analysis after initial nonoperative treatment for clubfeet: intermediate term followup at age 5

We conducted gait analysis following initial nonoperative clubfoot treatment to compare lower extremity kinematic (eg, ankle motion) and kinetic (eg, ankle power) characteristics between patients treated as infants with Ponseti casting or French physical therapy. This is a followup report of gait characteristics at age 5 years in patients who had previously been tested at age 2 years. One hundred-twenty five clubfeet in 90 patients (34 feet only Ponseti treatment, 40 only French PT, and 51 feet initial nonoperative treatment followed by surgery) were included. The gait characteristics were compared to those of age-matched normal control subjects. Ankle equinus during gait occurred in 5% of feet treated with the French method and none of those treated by the Ponseti method. Increased stance phase ankle dorsiflexion persisted in 24% of feet treated by the Ponseti method. Intoeing was seen in 1/3 of both the French and Ponseti methods. Ankle push-off power was decreased compared to normal in patients treated by both methods, and even more so in operated feet. The presence or absence of Achilles tenotomy did not affect ankle power. Gait characteristics of feet that did not have surgery and maintained correction were superior to those of operated feet.

Normative data for the dynamic pedobarographic profiles of children

In order to establish the clinical utility of pedobarography in the treatment of childhood foot pathology, a reliable set of pedobarograph data describing non-pathologic feet is required. The purpose of this study was to describe the pedobarographic profiles of normal children across all ages, with specific focus on young children and explore age-related differences in foot pressure patterns. The Tekscan HR Mat pressure measurement system was used in a protocol involving a dynamic test at self-selected speed and walking pattern of 146 normal children (age range 1.6-14.9 years). Relative force and timing data were obtained across five foot segments (heel, lateral midfoot, medial midfoot, lateral forefoot, and medial forefoot). Analysis of variance (ANOVA) techniques were applied to determine if there were any age-related differences in foot pressure profiles in children across four a priori pedobarograph variables: % of stance at initiation at the heel, % of stance at initiation at the medial midfoot, maximum % force at the heel, maximum % force at the medial midfoot. Differences in foot pressure profiles were distinguished across three age groups: (1) Group 1: <2 years; (2) Group 2: 2-5 years; and (3) Group 3: >5 years. Age-related differences in initiation patterns, force transmission, and the amount of time spent on each foot segment provide evidence for maturation of children's foot pressure profiles from a flatfoot pattern in the young child to a curvilinear pattern in the older child.