Der TMT-Index zur radiologischen Quantifizierung von Planovalgus-Deformitäten

[Flatfoot in children]

The diagnosis of flatfoot in children is made clinically. In most cases it is an age-appropriate benign physiological variant, as long as it can be passively and actively redressed and the child does not show any neurological abnormalities, especially under the age of 6 years. Treatment is only indicated for symptomatic variants. In the case of rigid flatfeet, further diagnostics are necessary to exclude neurological or structural causes. Subtalar arthroereisis has become established and is an effective but slightly invasive procedure. Further options include the lengthening and medial translational osteotomy of the calcaneus or the Cotton operation; however, the indications must always be critically questioned, especially for surgical but also for conservative treatment, even if it is the wish of the family.

Characteristic 3D foot motion patterns during gait of patients with Charcot-Marie-Tooth identified by cluster analysis

BACKGROUND

CMT is a clinically and genetically heterogenous disease with varying degrees of progression. Different foot deformities, gait and movement patterns are observed. In order to achieve an improved, targeted treatment strategy, the participants are divided into characteristic groups using a mathematical cluster analysis based on the data from the three-dimensional foot kinematics during walking.

METHODS

Outpatients from age 5-64 years (N = 33 participants, 62 feet) with a proven CMT type 1 (N = 16, 31 feet) or CMT without any further type assignment (N = 17, 31 feet) were retrospectively analyzed. After a standard clinical examination, participants underwent 3D gait analysis using the Oxford Foot Model. To classify the movement patterns, a k-means cluster analysis was calculated based on the principal component analysis (PCA) of the foot kinematics data. Gait parameters, clinical parameters and X-ray data were statistically tested.

RESULTS

The cluster analysis divided the gait data of the participants into two groups. Cluster 1 (N = 21 participants, 34 feet) showed increased dorsiflexion of the hindfoot and increased plantarflexion of the forefoot with cavus position in the sagittal plane, a hindfoot inversion and forefoot pronation with hindfoot varus in the frontal plane and in the transversal plane a forefoot adduction. Cluster 2 (N = 17 participants, 28 feet) deviated significantly from the norm mainly in the frontal plane and were characterized by a strong eversion of the hindfoot with a supination in the forefoot.

DISCUSSION

Based on the findings, the resultant clusters can be interpreted as cavovarus feet (cluster 1) and pes valgus (cluster 2). The most reliable variables in the 3D gait analysis to classify CMT feet with regard to significance are the ones in the frontal plane. This subdivision of participants goes hand in hand with the various necessary guidelines for orthopedic treatment.

Foot Typology, Dynamic and Static Weight Distribution, and Radiographic Changes After Subtalar Arthroereisis in Juvenile Symptomatic Flexible Flat Feet

Flexible flatfoot is among the most common skeletal disorders in childhood. This study describes the dynamic and static correction effects of subtalar arthroereisis in adolescents with flexible symptomatic flatfeet in comparison to normal subjects as well as to results before and after removal of metal. Eighteen adolescents with 25 symptomatic flexible flatfeet were treated surgically with a subtalar arthroereisis at a mean of 12.5 (10-16) years. At follow-up (mean 3.9 years, range 0.4-8), patients filled out the American Orthopaedic Foot and Ankle Society questionnaire, received radiographs and were examined using dynamic and static pedobarography as well as static hindfoot axis examination. Results were compared to healthy controls (n = 13; 26 feet). Surgically treated feet (n = 25) had better questionnaire results after surgery than before, but lower scores than healthy feet. Radiological parameters improved significantly after surgery. Removal of metal did not influence post-surgical results (follow-up 2.8 years). Surgically treated feet had larger contact areas than normal feet with predominance to the midfoot region. The relative maximum force, relative peak pressure and contact time were higher in the midfoot of treated feet compared to controls. When comparing pedobarography data of treated versus untreated feet of the same patients (subgroup n = 11 feet), there were no differences. Subtalar arthroereisis was able to effectively treat symptomatic flexible flatfeet in this population. Results improved significantly evaluating a questionnaire, radiographs, dynamic and static weight distribution, but were still worse than results of healthy feet. There was no relapse after removal of metal.

Does the way of weight-bearing matter? Single-leg and both-leg standing radiographic and pedobarographic differences in pediatric flatfoot

BACKGROUND

An exact definition is lacking for the term "weight-bearing" or different standing modalities when implementing foot radiographs for children and adults; moreover, only few studies have investigated the relationship between radiographic and pedobarographic measurements.

RESEARCH QUESTION

We hypothesized that the method of weight-bearing in single-leg and both-leg standing positions could influence the measurement results in radiographs and the distribution of foot pressure.

METHODS

This prospective study evaluated 33 children (66 feet) with flexible flatfoot deformities scheduled for subtalar screw arthroereisis surgery. Radiographs in the lateral and anteroposterior (AP) views were assessed independently in the single-leg and both-leg standing positions. Static pedobarography was performed as that for measuring weight-bearing. Standardized radiographic angles and pedobarographic data were analysed and correlated.

RESULTS

There were differences in radiographic measurements between the single-leg and both-leg standing positions, including the AP talocalcaneal angle (p = 0.032), AP talus-first metatarsal base angle (p = 0.003), AP talus-first metatarsal angle (p = 0.003), lateral calcaneal pitch angle (p = 0.001), talus-first metatarsal index (p = 0.004), and talocalcaneal index (p = 0.029). Moreover, differences between these two standing modalities were found in most of the static pedobarographic data, including the contact area (p = 0001), maximal force (p = 0.001), and peak pressure (p = 0.007). Overall, medial foot pressure increased more in both-leg standing than in the single-leg standing position, whereas radiographic measurements showed a more pronounced flatfoot deformity in the single-leg standing position. The AP talus-first metatarsal angle was the only angle or index with a significant association to some pedobarographic measurements in both standing modalities.

SIGNIFICANCE

As there are significant differences between single-leg standing and both-leg standing radiographic and static pedobarographic values, observers have to be precise in the definition of "weight-bearing" to gain reproducible and comparable study values in children and adults. We recommend acquiring both-leg standing foot radiographs because children with flexible flatfeet can stand more steadily in this position than in the single-leg standing position.

Evidence for foot orthoses for adults with flatfoot: a systematic review

Background

Flatfoot is characterised by the falling of the medial longitudinal arch, eversion of the hindfoot and abduction of the loaded forefoot. Furthermore, flatfoot leads to a variety of musculoskeletal symptoms in the lower extremity, such as knee or hip pain. The standard conservative treatment for flatfoot deformity is exercise therapy or treatment with foot orthoses. Foot orthoses are prescribed for various foot complaints. However, the evidence for the provision of foot orthoses is inconsistent. The aim of this systematic review is to synthesize the evidence of foot orthoses for adults with flatfoot.

Methods

A computerized search was conducted in August 2021, using the databases PubMed, Scopus, Pedro, Cochrane Library, and the Cochrane Central Register of Controlled Trials. Intervention studies of any design investigating the effects of foot orthoses were included, apart from case studies. Two independent reviewers assessed all search results to identify eligible studies and to assess their methodological quality.

Results

A total of 110 studies were identified through the database search. 12 studies met the inclusion criteria and were included in the review. These studies investigated prefabricated and custom-made foot orthoses, evaluating stance and plantar pressure during gait. The sample sizes of the identified studies ranged from 8 to 80. In most of the studies, the methodological quality was low and a lack of information was frequently detected.

Conclusion

There is a lack of evidence on the effect of foot orthoses for flatfoot in adults. This review illustrates the importance of conducting randomized controlled trials and the comprehensive development of guidelines for the prescription of foot orthoses. Given the weak evidence available, the common prescription of foot orthoses is somewhat surprising.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13047-021-00499-z.

[The talometatarsal-index ("TMT-Index") : A valuable X-ray parameter for differentiating between normal feet and planovalgus deformity in children and adolescents]

INTRODUCTION

The development of the shape of the shape from childhood to adulthood is a complex continuum. Deviations from this process occur frequently and, especially in asymptomatic patients, do not always include the need for therapeutic intervention. In the current S2-guideline on the juvenile flexible flatfoot, established x‑ray parameters for assessing the flatfoot deformity were judged to be sensitive, whereby no statement was made regarding the value of the parameters among themselves. The aim of the present work is to assess the talometatarsal Index (TMTInd) in comparison to established angle measurements.

METHODS

Twenty-two feet with and 22 feet without planovalgus deformity (age: 10-14 years) were investigated. Established radiological parameters (lateral view: talocalcaneal angle (TC-lat), calcaneal pitch angle (Calc-B), Costa-Bartani angle (Costa-B), talometatarsal‑I angle (TMTI-lat); dorsoplantar view: talometatarsal-I-basis angle (TMTIB), talonavicular coverage (TNG), calcaneal metatarsal- V angle (Calc-MTV), talocalcaneal angle (TC-dp), and talometatarsal‑I angle (TMTI-dp)) were measured on standardized X‑ray images and compared with the values of the TMTInd.

RESULTS

All parameters other than Calc-MTV, TC-dp, TC-lat and Calc‑B, showed a statistically significant difference between normal and planovalgus feet, although for almost all values measured (apart from TMTI-lat and TMTInd) there was a large overlap area (>10°) between the two groups. The comparison of TMTInd to all other parameters showed the highest discrimination factor (area-under-the-curve) for the TMTInd in the distinction between the groups.

CONCLUSION

Compared to conventional radiological parameters, the TMTInd shows the highest validity in the distinction between normal and planovalgus feet and can provide valuable information in clinical decision-making with regard to therapy specification.

Radiological tarsal bone morphology in adolescent age of congenital clubfeet treated with the Ponseti method

BACKGROUND

Major abnormalities of tarsal bone shape after surgical clubfoot treatment are well known from the literature. The Ponseti method has gained widespread acceptance in primary treatment of congenital clubfeet. Despite the longtime experience, data regarding the development of tarsal bones after this treatment are still rare. The aim of the study was therefore to evaluate radiographic parameters describing tarsal bone shape of clubfeet after Ponseti treatment and compare them to age-matched healthy feet.

METHODS

Twenty two consecutive severe clubfeet in 14 patients were investigated by repeated diagnostic ultrasound during the corrective process. Extent and temporal course of correction were documented with standardized X-rays after a mean follow-up of 12 years (between the ages of 10-14 years) and compared to a group of age-matched normal feet.

RESULTS

Reliability testing for all X-ray parameters showed good to excellent results. In comparison to the control group, all parameters except the radius of the trochlea (RT) were significantly altered in clubfeet with highest differences shown for the anterior talar motion segment (ATM), talonavicular coverage (TNC) and the talometatarsal index (TMT-Index). Differentiation between minor and major deformities showed significant differences only for the front tarsal index (FTI).

CONCLUSIONS

Tarsal bone shape of clubfeet treated by the Ponseti method differs significantly from normal feet. One of the most pronounced and clinically relevant difference of the clubfoot talus compared to the normal talus is the markedly reduced anterior talar motion segment.

Subtalar arthroereisis for the treatment of the symptomatic paediatric flexible pes planus: a systematic review

Subtalar arthroereisis has a controversial history and has previously been associated with high failure rates and excessive complications.A database search for outcomes of arthroereisis for the treatment of symptomatic paediatric flexible pes planus provided 24 articles which were included in this review, with a total of 2550 feet operated on.Post-operative patient-reported outcome measures recorded marked improvement. Patient satisfaction was reported as excellent in 79.9%, and poor in 5.3%. All radiological measurements demonstrated improvement towards the normal range following arthroereisis, as did hindfoot valgus, supination, dorsiflexion and Viladot grade.Complications were reported in 7.1% of cases, with a reoperation rate of 3.1%.Arthroereisis as a treatment for symptomatic paediatric flexible pes planus produces favourable outcomes and high patient satisfaction rates with a reasonable risk profile. There is still a great deal of negativity and literature highlighting the complications and failures of arthroereisis, especially for older implants.The biggest flaws in the collective literature are the lack of high-quality prospective studies, a paucity of long-term data and the heterogeneity of utilized outcome measures between studies. Cite this article: EFORT Open Rev 2021;6:118-129. DOI: 10.1302/2058-5241.6.200076.

Is it possible to define reference values for radiographic parameters evaluating juvenile flatfoot deformity? A case-control study

Background

Numerous radiographic parameters are described to evaluate juvenile flexible flatfeet. Reference values for these measurements are based on few studies. The purpose of this study was to determine boundary values among the most widely used radiographic measurements to evaluate juvenile flatfeet.

Methods

Twenty-two patients with normal hind-, midfoot configuration (group A: control group; 22 ft, mean age: 12,1 years) and 19 patients with flatfoot deformity (group B: study group; 22 ft, mean age: 12,4 years) were retrospectively analyzed. Nine radiographic parameters were measured (Talocalcaneal-angles, Calcaneal-pitch-angle, Costa-Bartani-angle, Talo-metatarsal-I-angles, Talo-first-metatarsal-base-angle, Talo-navicular-coverage, Calcaneus-fifth-metatarsal-angle). ROC curve analysis was used to calculate optimal differentiating thresholds of each parameter.

Results

Four out of nine parameters (TC-dp, TC-lat, Calc-MTV, Calc-P) were not statistically different between the groups and their ability to distinct between normal foot and flatfoot was low (AUC values = 0,660 - 0,819). Calculation of reference values for these parameters was not performed due to threshold ranges between the groups of > 10°. Reference values could be defined only for three parameters: TMTInd >(−)31°, TMTIB >(−)7,5°, TMT-lat > (−)13,5°. The TMTInd was shown to be a very reliable and valid combination of two measurements (TMTIB and TMT-lat) in the differentiation of normal feet and flatfeet (AUC = 0,998).

Conclusion

The calculation of reference values for established radiographic parameters used to evaluate juvenile flatfeet is difficult for most parameters. The TMTInd as a combination of TMTIB and TMT-lat has been shown to be reliable and valuable to distinct normal feet from flatfeet.

Is there a correlation between static radiographs and dynamic foot function in pediatric foot deformities?

BACKGROUND

Idiopathic flexible flatfeet, congenital clubfeet and pes cavovarus are the most common foot deformities in children. Accurate assessment to quantify the severity of these deformities by clinical examination alone can be challenging. Radiographs are a valuable adjunct for accurate diagnosis and effective treatment. However, static radiographs during relaxed standing may not reflect the dynamic changes in the foot skeleton during functional activities such as walking. Therefore, the aim of this study is to predict dynamic foot movements during walking from planar standing radiographs to reveal the significance of the radiographic analysis for the assessment of foot function.

METHODS

Patients 8-17 years with flexible flatfeet (FFF, n=217) recurrent clubfeet (RCF n=38) and overcorrected clubfeet (OCCF, n=71) of non-neurogenic or syndromic origin and pes cavovarus due to peripheral neuropathy (PNP, n=48) were retrospectively included. Patients underwent gait analysis with the Oxford Foot Model and radiographic examination in anterior-posterior and lateral view during standing. Multilinear predictor analysis of selected gait parameters was performed based on radiographic measures.

RESULTS

The variance that was explained by radiography was greatest for the transverse plane forefoot abduction with 33% for OCCF, 50% for RCF and 59% for PNP. Flatfeet and foot kinematics in the other planes or between rearfoot and tibia showed little or no relation.

CONCLUSIONS

The static measures of foot deformities by radiography could explain only a small amount of variance in foot kinematics during walking, in particular for FFF. An explanation may be that the forces during weight bearing bear little resemblance to those during gait in terms of neither magnitude nor direction. These findings suggest that foot function cannot be accurately assessed solely from static radiographic observations of the foot, commonly undertaken in clinical practice.

Cluster analysis to identify foot motion patterns in children with flexible flatfeet using gait analysis-A statistical approach to detect decompensated pathology?

INTRODUCTION

The paediatric flexible flatfoot constitutes the major cause of clinic visits for orthopaedic foot problems. It shows variations of deformities in different planes and locations of the foot and its indication for treatment have been extensively discussed. Despite its high prevalence there exists no classification of flatfeet during walking as a prerequisite for treatment decision. Therefore, the aim of this study is to classify flexible flatfeet based on 3D foot kinematics during walking.

METHODS

Patients age 7-17 years with flexible flatfeet (N = 129, 255 feet) of non-neurogenic or syndromic origin, were retrospectively included. Patients underwent gait analysis using the Oxford Foot Model after standard clinical examination. A k-means cluster analysis was performed on 3 scores derived from the principal component analysis of the foot kinematic waveforms over the gait cycle. Gait and clinical parameters were then statistically tested between clusters.

RESULTS

Cluster analysis revealed two groups of flexible flatfeet that were discriminated best by the inversion at push-off during walking. Cluster 2, including 110 feet, showed an average eversion instead of an inversion at push-off and a lower number of heel rises in the clinical test. Both was significantly different between clusters (p < 0.001).

DISCUSSION

Based on the findings, the resultant clusters can be interpreted as describing compensated and decompensated feet, with the latter presenting a group that may require surgical interventions, even if they are not yet present with pain. The hindfoot inversion capability at push-off is the most important variable in the 3D gait analysis to classify flexible flat feet.

Arthrorisis with calcaneostop screw in children corrects Talo-1st Metatarsal-Index (TMT-Index)

BACKGROUND

Arthrorisis (other terms: Arthrorhisis or Arthroreisis) with calcaneostop screw is one option for the treatment of flatfoot (Pes abductoplanovalgus) in children. The aim of the study was to analyze the amount of correction (for example Talo-1st Metatarsal-Index (TMT-Index)) and clinical outcome including pedographic assessment.

METHODS

In a prospective consecutive non-controlled clinical follow-up study, all patients that were treated with arthrorisis with calcaneostop screw from September 1st 2006 to August 31st, 2009 were included. One foot was operated at a time, and the contralateral foot was operated 3 months later if indicated. Postoperatively, 15 kg partial weight-bearing was performed for 6 weeks. The screws were removed after 2-year-followup. Assessment was performed before surgery, at two-year-followup, and at 2.5-year-followup. The assessment staging of posterior tibialis insufficiency, radiographs with full weight bearing (TMT-Index), pedography, and Visual-Analogue-Scale Foot and Ankle (VAS FA).

RESULTS

18 patients/31 feet were included in the study (age, 10.6 [8-12], 45% male). No complications were observed. In comparison with the preoperative parameters, the parameters posterior tibialis insufficiency stage, percentage of increased pedographic midfoot contact area and force were decreased, and TMT dorsoplantar/lateral/Index and VAS FA scores were increased at both followups (each p<.05). The parameters did not differ between followups (each p ≥.4).

CONCLUSIONS

All relevant parameters (stage of posterior tibialis insufficiency, TMT dorsoplantar/lateral/Index, pedographic midfoot contact area and force, VAS FA) improved after arthrorisis with calcaneostop screw (before and after screw removal) in pes abductoplanovalgus in children. Since the complication rate is very low, this method allows safe and predictable correction.

Lengthening osteotomy of the calcaneus and flexor digitorum longus tendon transfer in flexible flatfoot deformity improves talo-1st metatarsal-Index, clinical outcome and pedographic parameter

Lengthening osteotomy of the calcaneus (LO) and flexor digitorum longus tendon (FDL) transfer to the navicular is one option for the treatment of flexible flatfoot deformity (FD). The aim of the study was to analyse the amount of correction and clinical outcome including pedographic assessment. In a prospective consecutive non-controlled clinical followup study, all patients with FD that were treated with LO and FDL from September 1st 2006 to August 31st, 2009 were included. Assessment was performed before surgery and at 2-year-followup including clinical examination (with staging of posterior tibialis insufficiency) weight bearing radiographs (Talo-1st metatarsal angles (TMT)), pedography (increased midfoot contact area and force) and Visual Analogue Scale Foot and Ankle (VAS FA). 112 feet in 102 patients were analysed (age, 57.6 (13-82), 42% male). In 12 feet (9%) wound healing delay without further surgical measures was registered. All patients achieved full weight bearing during the 7th postoperative week. Until followup, revision surgery was done in 3 patients (fusion calcaneocuboid joint (n=2), correction triple arthrodesis (n=1)). 101 feet (90%) completed 2-year-followup. TMT dorsoplantar/lateral/Index and VAS FA scores were increased, and posterior tibialis insufficiency stage, pedographic midfoot contact area and force percentage were decreased (each p<.05). All relevant parameters (stage of posterior tibialis insufficiency, TMT angles and Index, pedographic midfoot contact area and force percentage, VAS FA) were improved 2 years after LO and FDL transfer to the navicular in FD. The complication rate was low. This method allows safe and predictable correction.

[Options and limits of subtalar arthroereisis in childhood]

The minimally invasive subtalar screw arthroereisis procedure is becoming an increasingly more established option for treating juvenile flexible flatfoot. The procedure is indicated in children who are 9-13 years old and have idiopathic juvenile flexible flatfoot that has progressed to a symptomatic pathology. Minimally invasive subtalar screw arthroereisis functions by a combination of mechanical and proprioceptive effects that allow for growth adjustment of the subtalar joint and with a low complication rate. This surgical intervention is contraindicated for treating fixed and secondary pes plano valgus. The subtalar screw is removed once the pediatric foot has stopped growing and results in permanent correction of the flexible flatfoot.

The stop screw technique--a simple and reliable method in treating flexible flatfoot in children

PURPOSE

The purpose of this study was to evaluate the stop screw method inserted with a minimal invasive technique in the treatment of flexible flatfoot in children.

MATERIALS AND METHODS

We evaluated the results in a series of 21 flat feet in the age group ranging from 8 to 14 years between 1999 and 2007. The correction was evaluated clinically by assessment of heel valgus angle, range of motion of the ankle joint, and the photopodographic grading. The radiological assessment was performed by measuring the talonavicular angulation (Meary's line).

RESULTS

At time of follow-up there was significant improvement in the heel valgus angle during rest and during tiptoe standing, significant improvement in the dorsiflexion from neutral position, and in podographic grading. Radiologically talonavicular angulation improved significantly from 162+/-8.9 degrees preoperatively to 174+/-5.8 degrees postoperatively.

CONCLUSION

We can conclude that subtalar arthroereisis is relatively simple, effective, and minimally invasive procedure in treating flexible flatfoot in pediatric age.

[Resection of talocalcaneal coalition in children and adolescents without and with osteotomy of the calcaneus]

OBJECTIVE

Resection of the painful medial talocalcaneal fibrocartilaginous or bony bridge, thereby restoration of mobility of the peritalar joint complex; in case of flatfoot deformity realignment of the hindfoot and midfoot by medial sliding calcaneal osteotomy and in some cases correction of equinus contracture by intramuscular lengthening of the gastrocnemius muscle.

INDICATIONS

Before growth arrest: --Bony or fibrocartilaginous bridge at the medial or dorsomedial talocalcaneal region with or without pain. --Rigid flatfoot deformity caused by talocalcaneal coalition. After growth arrest: --Resection is indicated only in case of local pain or hindfoot deformity.

CONTRAINDICATIONS

Resection is not indicated in cases without local pain or deformity after growth arrest or in cases with marked osteoarthritis of the talonavicular or talocalcaneal joint. If the cross section of the bony bridge exceeds 20 x 30 mm, resection is not recommended.

SURGICAL TECHNIQUE

Longitudinal incision at the medial facet of the subtalar joint. Exposure of the bony bridge. Subsequent resection until the talocalcaneal joint line is clearly visible. Gentle mobilization of the contracted subtalar joint to regain inversion. After resection of the coalition the distance between the corresponding bone areas should measure at least 10 mm. Bone wax is used to prevent bleeding and the gap is filled with fatty tissue. Additionally, in some cases an intramuscular lengthening of the contracted gastrocnemius muscle is necessary. In case of flatfoot deformity alignment should be restored by calcaneal lengthening and/or medializing sliding calcaneal osteotomy.

POSTOPERATIVE MANAGEMENT

The lower leg is immobilized in a cast for at least 2 weeks postoperatively; additional procedures require an extended period of immobilization. Afterwards, range of motion exercises are useful to regain motion of the peritalar joint complex.

RESULTS

24 resections of a talocalcaneal coalition in 22 pediatric or adolescent patients were carried out. The coalition was located at the medial joint facet in 18 cases and in the dorsomedial talocalcaneal region in seven cases (in one patient combination of both). Three patients presented with an additional calcaneonavicular coalition. A talocalcaneal bone bridge of the entire joint was found in five cases. In seven patients an intramuscular lengthening of the gastrocnemius muscle was necessary. In nine patients a calcaneal lengthening procedure, and in five patients a calcaneal sliding osteotomy were added. A lengthening in the region of a calcaneocuboid synostosis was untertaken in one case. After a mean follow-up of 21.2 months 17 patients are completely or nearly pain-free. Five patients still complain of pain, but are improved. Two patients were lost to follow-up.