The foot and ankle in cerebral palsy

Knee surveillance for ambulant children with cerebral palsy

Purpose

A majority of ambulant children with cerebral palsy (CP) develop progressive musculoskeletal pathology (MSP) during growth. Fixed flexion deformity at the knee joint (FFDKn) contributes to flexed knee gait and is prone to relapse after index multi-level surgery. This perspective introduces the concept of "knee surveillance" (KS), defined as a repeated systematic assessment of gait and knee range of motion until skeletal maturity. KS aims to detect early FFDKn, allowing for early intervention with minimally invasive techniques such as anterior distal femur hemiepiphysiodesis (ADFH), and reduce the need for higher-risk surgery such as distal femoral extension osteotomy (DFEO) and patellar tendon shortening (PTS).

Methods

Recent literature on the assessment of ambulant children with CP, consensus statements on indications for dose-based knee surgery, and the indications for ADFH have been reviewed and synthesized. These provide a preliminary evidence base for the concept of KS in ambulant children with CP.

Conclusion

We propose the concept of KS for ambulant children with CP. The goals of KS are early detection of knee flexion deformity, early intervention, less invasive surgery, and better long-term outcomes. There is preliminary evidence to suggest that soft-tissue surgery, in combination with ADFH, can reduce, or perhaps replace, the need for more invasive surgery such as DFEO and PTS.

Level of evidence

IV.

The effect of foot deformities on the interplay of forces within the foot: An analysis of multi-segment foot joint moments in cerebral palsy

BACKGROUND

Foot deformities are common in cerebral palsy (CP) and are likely caused by a disturbed interplay of forces in the foot. Evaluation of foot joint moments would therefore be highly relevant. However, kinetic foot models have not previously been applied to children with CP.

RESEARCH QUESTION

What is the difference in multi-segment foot joint moments between children with CP with foot deformities and children with typically developing (TD) feet?

METHODS

Children with spastic paresis were retrospectively included and compared to TD children. All children underwent clinical gait analysis, including a kinetic multi-segment foot model based on the Amsterdam Foot Model marker set. Internal joint moments of the ankle and midfoot (Chopart, Lisfranc) joints were calculated for each group.

RESULTS

67 feet of 40 children with spastic paresis (26 neutral, 25 planovalgus, 11 cavovarus, 5 equinovarus feet), and 15 feet of 15 TD children were included. Internal foot joint moments in children with CP with a cavovarus or equinovarus deformity showed an early ankle plantarflexion peak and increased valgus moments, increased Chopart plantarflexion and eversion moments, and increased Lisfranc abduction moments compared to TD feet. Planovalgus feet demonstrated early ankle plantarflexion and increased varus moments, increased Chopart adduction and reduced Lisfranc abduction moments compared to TD feet.

SIGNIFICANCE

The direction of the differences found in cavovarus, equinovarus and planovalgus feet indicates that the internal joint moments are generally opposite to the malalignment of the foot. This indicates that external joint moments, which are caused by external forces and can be assumed to be opposite and equal to the internal moments, may contribute to further development of the deformity. Hence, the forces that cause deterioration of foot deformity in CP may not only be a result of muscle actions, but also of altered external loading due to abnormal foot alignment. This highlights the importance of early interventions to realign the foot to prevent deterioration of a foot deformity.

Prevalence of valgus and varus foot deformities in 2784 children with cerebral palsy, a register-based cross-sectional study

BACKGROUND

Foot deformities, such as valgus and varus in the coronal plane and equinus in the sagittal plane, are common in children with cerebral palsy (CP). The purpose of this study was to describe the prevalence of coronal plane foot deformities and their association with the Gross Motor Function Classification System (GMFCS) level, age, CP subtype, and equinus in children with CP.

METHODS

A cross-sectional study was performed of 2784 children (1644 boys, 1140 girls), mean age 10 years, 2 months (standard deviation, 4.83), from the Swedish CP Follow-up Program and registry for 2021-2023. Single and multiple binary regression analyses estimated the association between coronal plane foot deformities (valgus or varus) and sex, age, GMFCS level, CP subtype, and equinus.

RESULTS

More than half (58%) the children with CP had valgus feet and 6% had varus feet. Valgus feet were more common in young children with high GMFCS levels, whereas the number of varus feet remained consistently low across all GMFCS levels. The prevalence of valgus feet was lower in older children at GMFCS I and II, but remained high in older children at GMFCS III-V. Coronal plane foot deformities were associated with higher GMFCS levels (odds ratio [OR] 11, 95% confidence interval [CI] 8-15 for GMFCS V), lower age (OR 1.5, 95% CI 1.3-1.7), and equinus (OR 1.9, 95% CI 1.4-2.5).

CONCLUSIONS

Most children with CP have a coronal plane foot deformity. Valgus is most commonly associated with higher GMFCS levels and lower age. These findings contribute to a mapping of the children with an increased risk of foot deformities and also highlight the need for continuous follow-up of foot deformities in children with CP.

Cerebral palsy in children: A clinical practice review

Cerebral palsy is a disorder characterized by abnormal tone, posture, and movement. In clinical practice, it is often useful to approach cerebral palsy based on the predominant motor system findings - spastic hemiplegia, spastic diplegia, spastic quadriplegia, extrapyramidal or dyskinetic, and ataxic. The prevalence of cerebral palsy is between 1.5 and 3 per 1,000 live births with higher percentage of cases in low to middle income countries and geographic regions. Pre-term birth and low birthweight are recognized as the most frequent risk factors for cerebral palsy; other risk factors include hypoxic-ischemic encephalopathy, maternal infections, and multiple gestation. In most cases of cerebral palsy, the initial injury to the brain occurs during early fetal brain development. Intracerebral hemorrhage and periventricular leukomalacia are the main pathologic findings found in preterm infants who develop spastic cerebral palsy. The diagnosis of cerebral palsy is primarily based on clinical findings. Early recognition of infants at risk for cerebral palsy as well as those with cerebral palsy is possible based on a combination of clinical history, use of standardized neuromotor assessment and findings on magnetic resonance imaging; however, in clinical practice, cerebral palsy is more reliably diagnosed by 2 years of age. Magnetic resonance imaging scan is indicated to delineate the extent of brain lesions and to identify congenital brain malformations. Genetic testing and tests for inborn errors of metabolism are indicated to identify specific disorders, especially treatable disorders. Because cerebral palsy is associated with multiple associated and secondary medical conditions, its management requires a sustained and consistent collaboration among multiple disciplines and specialties. With appropriate support, most children with cerebral palsy grow up to be adults with good functional abilities.

Multivariate functional principal component analysis and k-means clustering to identify kinematic foot types during gait in children with cerebral palsy

BACKGROUND

Children with neuromuscular disorders, such as cerebral palsy, frequently develop foot deformities, such as equinopronovalgus and equinosupovarus, leading to walking difficulties and discomfort. Traditional assessment methods, including clinical measures and radiographs, often fail to capture the dynamic nature of these deformities, resulting in suboptimal treatment. 3D gait analysis using multisegment foot models offers a more detailed understanding of these deformities.

RESEARCH QUESTION

To determine whether the combination of multisegment foot models, multivariate functional principal component analysis, and k-means cluster analyses could identify distinct, clinically relevant foot types in a large pediatric cohort with cerebral palsy.

METHODS

This was a retrospective analysis of 3D gait data from 197 patients with cerebral palsy collected using a multisegment foot model. Multivariate functional principal component analysis was used to reduce these data prior to using k-means clustering to identify foot posture clusters. Further analyses, including ANOVA and Fisher's Exact tests, were used to evaluate demographic, radiographic, and gait characteristics to explain the clinical relevance of each cluster.

RESULTS

Analysis of kinematic data from 371 feet revealed six clinically significant clusters, with a low misclassification rate of 2 %. One-factor ANOVAs demonstrated significant differences across clusters for all MPCs, whereas no significant differences were noted in basic anthropometric variables. Significant variations were observed in radiographic and gait function variables, and a strong association between GMFCS levels and cluster categorization was identified.

SIGNIFICANCE

The novel approach of integrating multivariate functional principal component analysis and k-means clustering identified a spectrum of foot deformities in children with CP, ranging from equinosupovarus to marked equinopronovalgus. This methodology provides an objective classification based on kinematic data and can facilitate improved diagnosis and treatment of cerebral palsy-related foot deformities.

Symptomatic flatfoot in cerebral palsy

PURPOSE OF REVIEW

The purpose of this review is to evaluate the current literature and best practices in the evaluation and treatment of symptomatic flatfoot in cerebral palsy.

RECENT FINDINGS

While techniques to reconstruct the neuromuscular flatfoot and reestablish bony levers have remained similar over time, the concept of surgical dosing has helped guide appropriate interventions based on the magnitude of disease and functional level of the child. Moreover, the utilization of multisegment foot modeling in motion analysis has allowed quantitative description of such deformities and their impact on gait.

SUMMARY

Future research should focus on refining operative indications and interventions with larger, multicenter, prospective cohorts to provide more robust evidence in surgical decision making. Long-term data are needed to confirm and compare efficacy of procedures. Radiographic data alone are not sufficient for describing functional foot position. Gait analysis with foot modeling and pedobarography along with patient-centered subjective outcomes will be needed in such investigations to make conclusive recommendations.

Surgery for foot deformities in MECP2 disorders: prevalence and risk factors

Foot deformities in methyl-CpG binding protein 2 (MECP2) disorders are thought to be common, but reports are scant. The purpose of this study was to report the prevalence and type of foot deformities and surgical management for MECP2 disorders. In this retrospective, comparative study, all children presenting between June 2005 and July 2020, with a genetically confirmed MECP2-related disorder, were included. The primary outcome measure was the prevalence of surgery for foot deformities. Secondary outcomes included type and frequency of foot surgeries, age at surgery, ambulatory status, genetic severity, presence of scoliosis/hip displacement, seizures, and associated comorbidities. Chi-square testing was utilized for the analysis of risk factors. Fifty-six patients (Rett syndrome: N  = 52, MECP2 duplication syndrome: N  = 4; 93% female) met the inclusion criteria. The mean age at first presentation to orthopedics was 7.3 (SD, 3.9) years, with a final follow-up of 4.5 (SD, 4.9) years. Seven (13%) patients developed foot deformities, most commonly equinus or equinovarus (five patients, 71%), requiring surgical management. The remaining two patients had calcaneovalgus. The most common surgical procedure was Achilles tendon lengthening, followed by triple arthrodesis, at a mean age of 15.9 (range: 11.4-20.1)  years. Hip displacement ( P  = 0.04), need for hip surgery ( P  = 0.001) and clinically relevant scoliosis ( P  = 0.04) were significant risk factors for the development of symptomatic foot deformities. Although not as prevalent as scoliosis or hip displacement, foot deformities are still relatively common in MECP2 disorders, often necessitating surgical intervention to improve brace tolerance. Level of evidence: Level III - a retrospective comparative study.

Arthrodesis of the first metatarsophalangeal joint for severe hallux valgus in adolescents with cerebral palsy: A retrospective comparison study of three surgical techniques

Purpose

We compared the outcomes of arthrodesis of the first metatarsophalangeal joint for severe hallux valgus in 31 adolescents with cerebral palsy, using three different methods of fixation: K-wires, non-locking plates, and locking plates.

Methods

Clinical outcomes included time to weight-bearing, fusion rates and surgical complications. Radiographic assessment included comparing pre- and post-operative hallux valgus angles, intermetatarsal angles, interphalangeal angles, and lateral metatarsophalangeal angles. Patient-reported outcomes included pre- and post-operative visual analogue scales addressing bunion pain and concerns, difficulties with wearing shoes and braces, and difficulties with foot hygiene.

Results

Of the 31 adolescents (16 male), 10 patients had K-wire fixation, 11 had a non-locking dorsal plate, and 10 had fixation with a dorsal locking plate. Mean age at surgery was 16 years (12-18 years) and mean follow-up was 4 years (2.7-6.5 years). Patients with K-wire fixation had delayed weight-bearing and had more complications than those managed by dorsal plating. There were significant improvements in radiographic parameters (except interphalangeal angle) and in patient-reported outcomes, in all groups (p < 0.001). However, radiographic and clinical outcomes were better in the dorsal plating groups compared to the K-wire group.

Conclusion

Arthrodesis of the first metatarsophalangeal joint gave good correction of deformity with improvements in symptoms and radiographic parameters in adolescents with cerebral palsy. We recommend dorsal plating that allowed early weight-bearing and had fewer complications with better clinical and radiographic outcomes, than K-wire fixation.

Level of evidence

IV: Retrospective case series.

Functional Repetitive Neuromuscular Magnetic Stimulation (frNMS) Targeting the Tibialis Anterior Muscle in Children with Upper Motor Neuron Syndrome: A Feasibility Study

Non-invasive neurostimulation as an adjunctive intervention to task-specific motor training is an approach to foster motor performance in patients affected by upper motor neuron syndrome (UMNS). Here, we present first-line data of repetitive neuromuscular magnetic stimulation (rNMS) in combination with personalized task-specific physical exercises targeting the tibialis anterior muscle to improve ankle dorsiflexion (functional rNMS (frNMS)). The main objective of this pilot study was to assess the feasibility in terms of adherence to frNMS, safety and practicability of frNMS, and satisfaction with frNMS. First, during 10 training sessions, only physical exercises were performed (study period (SP) A). After a 1 week break, frNMS was delivered during 10 sessions (SPC). Twelve children affected by UMNS (mean age 8.9 ± 1.6 years) adhered to 93% (SPA) and 94% (SPC) of the sessions, and omittance was not related to the intervention itself in any case. frNMS was safe (no AEs reported in 88% of sessions, no AE-related discontinuation). The practicability of and satisfaction with frNMS were high. Patient/caregiver-reported outcomes revealed meaningful benefits on the individual level. The strength of the ankle dorsiflexors (MRC score) clinically meaningfully increased in four participants as spasticity of ankle plantar flexors (Tardieu scores) decreased in four participants after SPC. frNMS was experienced as a feasible intervention for children affected by UMNS. Together with the beneficial effects achieved on the individual level in some participants, this first study supports further real-world, large-scale, sham-controlled investigations to investigate the specific effects and distinct mechanisms of action of frNMS.

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.

Efficacy of conservative treatment for spastic cerebral palsy children with equinus gait: a systematic review and meta-analysis

Background

Comparisons between various conservative managements of spastic equinus deformity in cerebral palsy demonstrated limited evidences, to evaluate the efficacy of conservative treatment among cerebral palsy children with spastic equinus foot regarding gait and ankle motion.

Methods

Studies were identified from PubMed and Scopus up to February 2022. Inclusion criteria were randomized controlled trial (RCT), conducted in spastic cerebral palsy children with equinus deformity, aged less than 18 years, compared any conservative treatments (Botulinum toxin A; BoNT-A, casting, physical therapy, and orthosis), and evaluated gait improvement (Physician Rating Scale or Video Gait Analysis), Observational Gait Scale, Clinical Gait Assessment Score, ankle dorsiflexion (ankle dorsiflexion at initial contact, and passive ankle dorsiflexion), or Gross Motor Function Measure. Any study with the participants who recently underwent surgery or received BoNT-A or insufficient data was excluded. Two authors were independently selected and extracted data. Risk of bias was assessed using a revised Cochrane risk-of-bias tool for randomized trials. I² was performed to evaluate heterogeneity. Risk ratio (RR), the unstandardized mean difference (USMD), and the standardized mean difference were used to estimate treatment effects with 95% confidence interval (CI).

Results

From 20 included studies (716 children), 15 RCTs were eligible for meta-analysis (35% had low risk of bias). BoNT-A had higher number of gait improvements than placebo (RR 2.64, 95% CI 1.71, 4.07, I² = 0). Its combination with physical therapy yielded better passive ankle dorsiflexion at knee extension than physical therapy alone (USMD = 4.16 degrees; 95% CI 1.54, 6.78, I² = 36%). Casting with or without BoNT-A had no different gait improvement and ankle dorsiflexion at knee extension when compared to BoNT-A. Orthosis significantly increased ankle dorsiflexion at initial contact comparing to control (USMD 10.22 degrees, 95 CI% 5.13, 15.31, I² = 87%).

Conclusion

BoNT-A and casting contribute to gait improvement and ankle dorsiflexion at knee extension. BoNT-A specifically provided gait improvement over the placebo and additive effect to physical therapy for passive ankle dorsiflexion. Orthosis would be useful for ankle dorsiflexion at initial contact.

Trial registration PROSPERO number CRD42019146373.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-022-03301-3.

Pediatric hallux valgus: An overview of history, examination, conservative, and surgical management

Pediatric hallux valgus (PHV), while relatively rare, is still often encountered by general pediatricians. Herein, we concisely summarize the existing literature regarding the pathogenesis, associated conditions, clinical diagnosis, radiographic characteristics, conservative management, and surgical management of PVH. Though PHV is generally considered benign, the progression of hallux valgus can result in complications. The presence of an open physis in the pediatric age group delineates first line treatment choices, whenever possible, as nonoperative. The general exception to this recommendation is for children with neuromuscular and connective tissues disease who may benefit from earlier surgical management. If conservative approaches fail prior to skeletal maturity, the risk of recurrence and need for revision surgery should be discussed with patients and their families before surgical referral is made. The current review was conducted to aid primary care providers in better understanding the pathogenesis, associated conditions, and intervention options available to manage PHV.

Efficacy Comparison of 3 Kinds of Distal Tibial Hemiepiphyseal Implants in the Treatment of Postoperative Ankle Valgus of Congenital Pseudarthrosis of the Tibia

BACKGROUND

Congenital pseudarthrosis of the tibia (CPT) is a complex and serious disease in orthopaedics which often requires multiple operations for treatment. Postoperative ankle valgus deformity is easily seen after the operation of CPT. The aim of this study is to retrospectively evaluate the effectiveness of three different implants for treating postoperative ankle valgus after CPT.

METHODS

A total of 41 patients with postoperative ankle valgus after CPT from December 2010 to July 2019 were selected. Of these 41 patients, 23 patients were treated with "U"-shaped staple, 10 patients were treated with hollow screw and 8 patients were treated with cortical bone screw. The evaluation index was tibiotalar angle. The general data, preoperative, postoperative, and final follow-up imaging data were recorded, and the deformity correction rate and complications were compared.

RESULTS

All the patients were performed with postoperative follow-up visit for at least 12 months (31 mo on average). In the "U"-shaped staple group, the preoperative tibiotalar angle was 74.8±4.8 degrees, the tibiotalar angle was 85.8±4.5 degrees when the internal fixation was removed; in the hollow screw group, the average preoperative tibiotalar angle was 72.2±6.1 degrees, the average tibiotalar angle was 88.4±5.1 degrees when the internal fixation was removed; in the cortical bone screw group, the average preoperative tibiotalar angle was 75.1±4.2 degrees, the average tibiotalar angle was 88.4±5.1 degrees when the internal fixation was removed. The correction rate of the "U"-shaped staple group was 0.71 degrees/month, with that of in the hollow screw group and cortical bone screw group being 0.64 degrees/month and 0.61 degrees/month, respectively. There was no significant difference in the correction rate between the 3 groups. One case of internal fixation complication was reported in the hollow screw group; 2 cases of missing correction effect were reported, 1 in cortical bone screw group and 1 in hollow screw group; and 2 cases showing symptom of wound pain were reported in the "U"-shaped staple group.

CONCLUSION

Ankle valgus is a common postoperative complication of congenital tibial pseudarthrosis. Temporary hemiepiphysiodesis with "U"-shaped staple or screws is an effective treatment for postoperative ankle valgus deformity of CPT in children.

LEVEL OF EVIDENCE

Level IV-retrospective study.

Surgical Management of Foot and Ankle Deformities in Cerebral Palsy

Children with cerebral palsy (CP) are at a high risk of developing foot and ankle deformities that can impact function, brace/shoe fit, and seating. The 3 commonly observed foot and ankle segmental malalignment patterns include equinus, planovalgus, and equinovarus. Assessment of foot deformities is multifaceted, requiring the collection and integration of data from a combination of sources that include the clinical history, standardized physical examination, observational and quantitative gait analysis, GMFCS classification, and radiographic findings. Surgical procedures are determined by identifying all segmental malalignments and assessing the contribution of dynamic or flexible soft-tissue imbalance, fixed soft-tissue imbalance, and skeletal deformities.

What are the long-term outcomes of lateral column lengthening for pes planovalgus in cerebral palsy?

BACKGROUND

Lateral column lengthening (LCL) is commonly performed on children and adolescents with cerebral palsy (CP) for correction of pes planovalgus (PPV). There are limited reports of the long-term outcomes of this procedure. The purpose of this study was to examine the long-term results of LCL for correction of PPV in individuals with CP by evaluating subjects when they had transitioned to adulthood and were entering the workforce.

METHODS

Clinical assessments, quantitative gait analysis including the Milwaukee Foot Model (MFM) for segmental foot kinematics, and patient reported outcomes were collected from 13 participants with CP treated with LCL for PPV in childhood (average age 24.4 ± 5.7 years, average 15.3 ± 8.5 years since LCL). Additionally, 27 healthy adults average age 24.5 ± 3.6 years functioned as controls.

RESULTS

Strength and joint range of motion were reduced in the PPV group (p < 0.05). Sixty nine percent showed operative correction of PPV based on radiologic criteria. Gait analysis showed reduced walking speed and stride length, as well as midfoot break and residual forefoot abduction. Patient reported outcomes indicated that foot pain was not the only factor that caused limited activity and participation. LCL surgery for PPV in childhood resulted in long-term operative correction. Decreased ankle passive range of motion and strength, subtalar joint arthritic changes, inefficient and less stable ambulation, and problems with participation (difficulties in physical function, education, and employment) were observed in the long-term.

CONCLUSION

This study identified postoperative impairments and limitations to guide future clinical decision-making. These results provide clinicians and researchers the common residual and recurrent issues for these individuals as they age. The inclusion of contextual factors that influence the disease and impairments can equip these individuals with enhanced skills they need as they transition into adulthood.

Usability and performance validation of an ultra-lightweight and versatile untethered robotic ankle exoskeleton

BACKGROUND

Ankle exoskeletons can improve walking mechanics and energetics, but few untethered devices have demonstrated improved performance and usability across a wide range of users and terrains. Our goal was to design and validate a lightweight untethered ankle exoskeleton that was effective across moderate-to-high intensity ambulation in children through adults with and without walking impairment.

METHODS

Following benchtop validation of custom hardware, we assessed the group-level improvements in walking economy while wearing the device in a diverse unimpaired cohort (n = 6, body mass = 42-92 kg). We also conducted a maximal exertion experiment on a stair stepping machine in a small cohort of individuals with cerebral palsy (CP, n = 5, age = 11-33 years, GMFCS I-III, body mass = 40-71 kg). Device usability metrics (device don and setup times and System Usability Score) were assessed in both cohorts.

RESULTS

There was a 9.9 ± 2.6% (p = 0.012, range = 0-18%) reduction in metabolic power during exoskeleton-assisted inclined walking compared to no device in the unimpaired cohort. The cohort with CP was able to ascend 38.4 ± 23.6% (p = 0.013, range = 3-132%) more floors compared to no device without increasing metabolic power (p = 0.49) or perceived exertion (p = 0.50). Users with CP had mean device don and setup times of 3.5 ± 0.7 min and 28 ± 6 s, respectively. Unimpaired users had a mean don time of 1.5 ± 0.2 min and setup time of 14 ± 1 s. The average exoskeleton score on the System Usability Scale was 81.8 ± 8.4 ("excellent").

CONCLUSIONS

Our battery-powered ankle exoskeleton was easy to use for our participants, with initial evidence supporting effectiveness across different terrains for unimpaired adults, and children and adults with CP. Trial registration Prospectively registered at ClinicalTrials.gov (NCT04119063) on October 8, 2019.

Radiographic and plantar pressure assessment of pes planovalgus severity in children with cerebral palsy

BACKGROUND

Pes planovalgus is common in children with cerebral palsy. Although severity influences treatment, there still lacks standard clinical measurements to objectively quantify pes planovalgus in this population. The comparison of pedobarographic data and radiographic measurements to clinical evaluation has not been reported in this population.

METHODS

395  feet were identified from a population of ambulatory pediatric patients with cerebral palsy. Each patient initially underwent clinical evaluation by an experienced physical therapist who classified feet as: 136 controls, 116 mild, 100 moderate, and 43 severe pes planovalgus. Quantitative measurements were then calculated from antero-posterior and lateral radiographs of the foot. Pedobarographic analysis included the arch index, center of pressure index, and a newly defined medial index.

FINDINGS

A multivariate analysis was performed on the radiographic and pedobarographic measurements collected. It identified seven variables that improved objective classification of pes planovalgus severity when utilized together. These include the foot progression angle, initial contact force, arch index, medial index, antero-posterior talonavicular coverage, lateral calcaneal pitch and lateral Meary's angle. While the lateral calcaneal pitch angle statistically differed amongst all severity classes, no pedobarographic value statistically differed between all severity classes.

INTERPRETATION

Overall, the combination of radiographic and pedobarographic measurements provides valuable information for objectively classifying severity of pes planovalgus in children with cerebral palsy by utilizing these values together rather than independently. In a clinical setting, radiographs and pedobarographic data may be obtained to enhance assessment of severity and guide treatment.

Musculoskeletal Pathology in Cerebral Palsy: A Classification System and Reliability Study

This article presents a classification of lower limb musculoskeletal pathology (MSP) for ambulant children with cerebral palsy (CP) to identify key features from infancy to adulthood. The classification aims to improve communication, and to guide referral for interventions, which if timed appropriately, may optimise long-term musculoskeletal health and function. Consensus was achieved by discussion between staff in a Motion Analysis Laboratory (MAL). A four-stage classification system was developed: Stage 1: Hypertonia: Abnormal postures are dynamic. Stage 2: Contracture: Fixed shortening of one or more muscle-tendon units. Stage 3: Bone and joint deformity: Torsional deformities and/or joint instability (e.g., hip displacement or pes valgus), usually accompanied by contractures. Stage 4: Decompensation: Severe pathology where restoration of optimal joint and muscle-tendon function is not possible. Reliability of the classification was tested using the presentation of 16 clinical cases to a group of experienced observers, on two occasions, two weeks apart. Reliability was found to be very good to excellent, with mean Fleiss' kappa ranging from 0.72 to 0.84. Four-stages are proposed to classify lower limb MSP in children with CP. The classification was reliable in a group of clinicians who work together. We emphasise the features of decompensated MSP in the lower limb, which may not always benefit from reconstructive surgery and which can be avoided by timely intervention.

Ultrasonographic Measurement of Talar Cartilage Thickness in Patients With Cerebral Palsy

OBJECTIVE

Foot deformities are one of the most common musculoskeletal problems in children with cerebral palsy (CP). These deformities affect the walking ability and function of the patients. Talar cartilage is the hyaline joint cartilage of the tibiotalar joint that plantarflexes and dorsiflexes of the ankle. The aim of this study was to determine whether talar cartilage thickness was affected in children with ambulant diplegic CP.

DESIGN

Forty patients with diplegic CP (19 boys, 21 girls) and 40 age-, sex-, and weight-matched healthy control subjects (20 boys, 20 girls) were included in the study. The demographic and clinical characteristics of the patients, including age, sex, and body mass index, were recorded. Patients were classified using the Gross Motor Function Classification System. A 12-MHz linear probe was used for ultrasonographic cartilage measurements at the tibiotalar joint according to European Musculoskeletal Ultrasound Study Group (EURO-MUSCULUS) and the Ultrasound Study Group in Physical and Rehabilitation Medicine (USPRM) scanning protocols.

RESULTS

Mean talar cartilage thickness was significantly decreased in the CP group compared with the healthy control group (P < 0.001). There was a significant negative correlation between Gross Motor Function Classification System levels and talar cartilage thickness measurements (P < 0.001, Tb = -0.695).

CONCLUSION

This study demonstrates that patients with CP have a thinner talar cartilage compared with healthy control subjects.

Surface EMG in Clinical Assessment and Neurorehabilitation: Barriers Limiting Its Use

This article addresses the potential clinical value of techniques based on surface electromyography (sEMG) in rehabilitation medicine with specific focus on neurorehabilitation. Applications in exercise and sport pathophysiology, in movement analysis, in ergonomics and occupational medicine, and in a number of related fields are also considered. The contrast between the extensive scientific literature in these fields and the limited clinical applications is discussed. The "barriers" between research findings and their application are very broad, and are longstanding, cultural, educational, and technical. Cultural barriers relate to the general acceptance and use of the concept of objective measurement in a clinical setting and its role in promoting Evidence Based Medicine. Wide differences between countries exist in appropriate training in the use of such quantitative measurements in general, and in electrical measurements in particular. These differences are manifest in training programs, in degrees granted, and in academic/research career opportunities. Educational barriers are related to the background in mathematics and physics for rehabilitation clinicians, leading to insufficient basic concepts of signal interpretation, as well as to the lack of a common language with rehabilitation engineers. Technical barriers are being overcome progressively, but progress is still impacted by the lack of user-friendly equipment, insufficient market demand, gadget-like devices, relatively high equipment price and a pervasive lack of interest by manufacturers. Despite the recommendations provided by the 20-year old EU project on "Surface EMG for Non-Invasive Assessment of Muscles (SENIAM)," real international standards are still missing and there is minimal international pressure for developing and applying such standards. The need for change in training and teaching is increasingly felt in the academic world, but is much less perceived in the health delivery system and clinical environments. The rapid technological progress in the fields of sensor and measurement technology (including sEMG), assistive devices, and robotic rehabilitation, has not been driven by clinical demands. Our assertion is that the most important and urgent interventions concern enhanced education, more effective technology transfer, and increased academic opportunities for physiotherapists, occupational therapists, and kinesiologists.

Foot and Ankle Musculoskeletal Imaging of Pediatric Patients With Cerebral Palsy

OBJECTIVE. Any combination of abnormal positioning of the ankle, hindfoot, midfoot, and forefoot is possible in the context of cerebral palsy, but some patterns are more common than others. The purpose of this article is to discuss the radiographic manifestations and surgical management of the following common conditions: equinus, equinoplanovalgus, equinocavovarus, vertical talus, oblique talus, hallux valgus, and ankle valgus. CONCLUSION. CP is defined by abnormalities of the developing fetal or infant brain that result in permanent central motor dysfunction. Foot and ankle deformities are very common in the patients with CP, occurring in up to 93% of such patients as a result of underlying abnormal muscle tone, impaired motor control, and dynamic muscle imbalance. Radiologists must develop knowledge of the most common changes in alignment and basic techniques for correction to better recognize abnormalities and improve communication with orthopedic colleagues.

The effect of mono- versus multi-segment musculoskeletal models of the foot on simulated triceps surae lengths in pathological and healthy gait

BACKGROUND

Estimating muscle-tendon complex (MTC) lengths is important for planning of soft tissue surgery and evaluating outcomes, e.g. in children with cerebral palsy (CP). Conventional musculoskeletal models often represent the foot as one rigid segment, called a mono-segment foot model (mono-SFM). However, a multi-segment foot model (multi-SFM) might provide better estimates of triceps surae MTC lengths, especially in patients with foot deformities.

RESEARCH QUESTION

What is the effect of a mono- versus a multi-SFM on simulated ankle angles and triceps surae MTC lengths during gait in typically developing subjects and in children with CP with equinus, cavovarus or planovalgus foot deformities?

METHODS

50 subjects were included, 10 non-affected adults, 10 typically developing children, and 30 children with spastic CP and foot deformities. During walking trials, marker trajectories were collected for two marker models, including a mono- and multi-segment foot; respectively Newington gait model and Oxford foot model. Two musculoskeletal lower body models were constructed in OpenSim with either a mono- or multi-SFM based on the corresponding marker models. Normalized triceps surae MTC lengths (soleus, gastrocnemius medialis and lateralis) and ankle angles were calculated and compared between models using statistical parametric mapping RM-ANOVAs. Root mean square error values between simulated MTC lengths were compared using Wilcoxon signed-rank and rank-sum tests.

RESULTS

Mono-SFM simulated significantly more ankle dorsiflexion (7.5 ± 1.2°) and longer triceps surae lengths (difference; soleus:2.6 ± 0.29 %, gastrocnemius medialis:1.7 ± 0.2 %, gastrocnemius lateralis:1.8 ± 0.2%) than a multi-SFM. Differences between models were larger in children with CP compared to typically developing children and larger in the stance compared to the swing phase of gait. Largest differences were found in children with CP presenting with planovalgus (4.8 %) or cavovarus (3.8 %) foot deformities.

SIGNIFICANCE

It is advisable to use a multi-SFM in musculoskeletal models when simulating triceps surae MTC lengths, especially in individuals with planovalgus or cavovarus foot deformities.

Musculoskeletal Imaging in Cerebral Palsy

Scoliosis, hip dysplasia, and other lower extremity deformities are common musculoskeletal pathology found in patients with cerebral palsy. Imaging studies allow for an improved identification of patients with these issues, help to understand the pathology, and aid in planning treatment strategies. Most of these deformities are visualized using plain radiographic techniques. Occasionally, as in the case of preoperative planning, advanced imaging, such as computerized topography and MRI, can be used for additional information. This article provides insight into the various imaging techniques for these musculoskeletal issues and aids in better care for patients with cerebral palsy.

Cerebral palsy - beyond hip deformities

Cerebral palsy is a neurologic condition with myriad musculoskeletal and articular manifestations. While every patient is unique with innumerable variations in presentation, symptoms and treatments, there are broad themes and recognizable patterns of development. Many of these findings spill over to other neurodevelopmental disorders, and lessons learned from children with cerebral palsy translate well to multiple neurologic conditions. This review focuses on the more common manifestations involving the spine, knee, foot and ankle, with an emphasis on collecting and describing imaging features, along with clinical and radiologic pearls and pitfalls.

Radiographic Assessment of Foot Alignment in Juvenile Hallux Valgus and Its Relationship to Flatfoot

BACKGROUND

The relationship between juvenile hallux valgus (JHV) and flatfoot has not been clearly established. The aim of this study was to assess radiographic measurements in feet with JHV compared with matched controls and to investigate whether the foot alignment of JHV is related to flatfoot.

METHODS

We retrospectively reviewed 163 patients with JHV as defined as hallux valgus angle greater than 20 degrees and intermetatarsal greater than angle than 10 degrees. Patients with open physes of the feet and who had weight-bearing radiographs of the feet were included. Another 55 normal participants served as controls. Patients with JHV were divided into 2 subgroups: Group 1 included patients with asymptomatic JHV and group 2 consisted of those treated with correctional surgery for painful JHV. Twelve radiographic indices were analyzed, including calcaneal pitch angle, tibiocalcaneal angle, talocalcaneal angle, naviculocuboid overlap, talonavicular coverage angle, lateral talo-first metatarsal angle, anteroposterior talo-first metatarsal angle, metatarsus adductus angle, hallux valgus angle, intermetatarsal angle, distal metatarsal articular angle, and first metatarsal cuneiform angle. The groups were compared by age, gender, and the above radiographic parameters.

RESULTS

There was no significant difference in hindfoot alignment of patients with JHV and controls. Naviculocuboid overlap (P <.001), lateral talo-first metatarsal angle (P = .002), and metatarsus adductus angle (P = .004) were significantly greater in patients with JHV than in controls, whereas the anteroposterior talo-first metatarsal angle (P = .026) was significantly less. Symptomatic and asymptomatic JHV patient subsets showed no significant radiologic differences.

CONCLUSION

Radiographic profiles in patients with JHV were inconsistent with regard to features of flatfoot, and foot alignment was unrelated to the presence of symptoms or degree of deformity in JHV.

LEVEL OF EVIDENCE

Level III, retrospective comparative series.

Preliminary Study of the Effect of Training With a Gaming Balance Board on Balance Control in Children With Cerebral Palsy: A Randomized Controlled Trial

OBJECTIVE

A new protocol based on the use of a gaming balance board for children with cerebral palsy was tested.

DESIGN

A total of 56 children with cerebral palsy were enrolled and randomly divided into two groups: experimental and control. The children in experimental group underwent 12 wks of rehabilitation using their foot to play personal computer games with the proposed balance board, whereas those in the control group played personal computer games with a computer mouse in the standing position. Balance control was assessed before and after the intervention using the Zebris FDM System for measuring the center of pressure. The Pediatric Balance Scale and 2-min walk test were used for evaluating functional balance.

RESULTS

In the analysis of covariance, the proposed new balance board used for the personal computer games decreased the postural sway (sway path, F = 6.95, P = 0.011; sway area, F = 11.79, P = 0.001) and improved the performance of the functional balance tests.

CONCLUSIONS

This study demonstrated the possibility that this new gaming balance board can be used for balance control in children with cerebral palsy.

Radiological outcome of calcaneo-cuboid-cuneiform osteotomies for planovalgus feet in cerebral palsy children: Relationship with pedobarography

BACKGROUND

Calcaneo-cuboid-cuneiform (triple C) osteotomies correct all levels of deformity of flexible planovalgus feet (PVF) in patients with cerebral palsy (CP). The objective was assessing short term results and the hypothesis was that static pedobarography correlates with radiological parameters as outcome measures.

METHODS

A prospective case series of consecutive skeletally immature ambulatory spastic CP patients above the age of 4 years who underwent triple C for PVF. Assessment was done using static pedobarography and standing dorsoplantar (DP) and lateral radiographs. The calcaneal pitch, lateral talocalcaneal, lateral and DP talo-first metatarsal, and DP talonavicular coverage angles were measured.

RESULTS

Eighteen feet (12 patients) were analyzed. Postoperative changes in lateral and DP talo-first metatarsal, and DP talonavicular coverage angles were statistically significant (P-value=0 with paired T-test). Post operative foot pressure changes were significant and highest in mid-foot. Both outcomes were related together with a p-value of 1 using McNemar test.

CONCLUSIONS

The triple C and associated soft tissue procedures reliably corrected PVF deformities. Static pedobarography can be used for postoperative assessment of adequate correction.

Double hindfoot arthrodesis technique for the treatment of severe equino-plano-valgus foot deformity in cerebral palsy: long-term results and radiological evaluation

The aim of this study was to evaluate the clinical and radiological results of a double arthrodesis technique for the treatment of equino-plano-valgus foot deformity in pediatric patients affected by cerebral palsy. A retrospective evaluation was performed on 175 feet surgically treated with a talonavicular and calcaneocuboid joint fusion technique. The average age at surgery was 14.7 years (range: 12-20 years). Visual analogue scale for pain score, Gross Motor Function Classification System scale, talonavicular angle, Costa-Bertani angle, and Kite's angle on standard weight bearing radiographs were evaluated preoperatively and postoperatively. The mean clinical follow-up was 62.4 months (range: 12-112 months). The mid Gross Motor Function Classification System scale value did not show a significant improvement in any of the subgroups considered. A significant improvement in the visual analogue scale for pain score value was evident 6 months after surgery. Radiological examination showed a statistically significant improvement in the talonavicular angle (average 7.4°) and the Costa-Bertani angle (average 128.5°). Complications occurred in 8.6% of cases. The described surgical technique is safe and efficacious, and could represent a useful option of treatment of equino-plano-valgus severe deformity in cerebral palsy patients older than 12 years of age.

The effect of joint translation constraint on within-participant variability of kinematics and kinetics during running in cerebral palsy

BACKGROUND

Biomechanical data in cerebral palsy are inherently variable but no optimal model of translational joint constraint has been identified. The primary aim of this study was to determine which model of translational joint constraint resulted in the lowest within-participant variability of lower limb joint angles and moments. The secondary aim was to determine which model best distinguished known functional groups in Cerebral Palsy.

METHODS

Three models (three degrees of freedom, six degrees of freedom and six degrees of freedom with specified joint translation constraint) were applied to data from running trials of 40 children with cerebral palsy.

FINDINGS

Joint angle standard deviations were largest using the six degrees of freedom model and smallest using the constrained six degrees of freedom model (p < 0.050). For all joints in all planes of motion, joint moment standard deviations were largest using the six degrees of freedom model and smallest using the constrained six degrees of freedom model; standard deviations using the constrained model were smaller than the three degrees of freedom model by 10-30% of moment magnitude (0.01-0.03 Nm/kg; p < 0.001). The six degrees of freedom models distinguished functional subgroups with larger effect size than the three degrees of freedom model only for hip power generation in swing.

INTERPRETATION

A model with specified joint constraint minimized within-participant variability during running and was useful for detecting differences in functional capacity in cerebral palsy.

Surgical correction of hallux valgus deformity in children with cerebral palsy

Objective

This study aimed to present a treatment algorithm for the correction of the hallux valgus deformity in Cerebral Palsy (CP) patients and to discuss the outcomes based on our clinical and radiological results.

Methods

29 patients (45 feet) were included in the study. The mean age of the patients at the time of the surgery was 14 (range 6–22) years. The mean follow-up was 33 (range 22–59) months. A reconstructive procedure was performed on 19 patients (27 feet); a soft tissue surgery and exostectomy of the bunion in six patients (11 feet); and MTP joint arthrodesis in four patients (7 feet). The hallux valgus angle (HVA) and the anteroposterior intermetatarsal angle (IMA) were used for radiologic evaluation and the DuPont Bunion Rating Score was used for clinical evaluation.

Results

The follow-up period was 36 (range 22–59) months in reconstructive group, 27 (range 24–29) months in soft tissue group, and 29 (range 23–41) months in MTP arthrodesis group. Significant improvements were detected in hallux valgus angle in three groups postoperatively but in soft tissue group correction loss was observed during follow up. Best results were achieved in arthrodesis group and worse in soft tissue group in terms of clinical evaluation.

Conclusion

According to our results isolated soft tissue procedures are ineffective in CP patients. Soft tissue procedure combined with metatarsal osteotomy has satisfactory results.

Level of evidence

Level IV, therapeutic study.

Long-Term Effects of Orthoses Use on the Changes of Foot and Ankle Joint Motions of Children With Spastic Cerebral Palsy

BACKGROUND

Orthoses commonly are prescribed to children with cerebral palsy (CP) to provide foot correction and to improve ambulatory function. Immediate effects of ankle foot orthosis (AFOs) have been investigated, but long-term kinematic effects are lacking clinical evidence.

OBJECTIVE

To determine changes in 3-dimensional ankle and foot segment motion in pediatric patients with CP between initial and follow-up visits (18-month average time differences) in both barefoot gait and gait with their AFO. We also investigated intravisit changes between barefoot and AFO gait.

DESIGN

A prospective cohort study.

SETTING

Children's Hospital of Wisconsin, Department of Orthopaedic Surgery, Medical College of Wisconsin.

PATIENTS

A total of 23 children with CP, mean age 10.5 years (6.2-18.1 years) were clinically prescribed either a solid ankle foot orthotic (SAFO), hinged ankle foot orthotic (HAFO), or supramalleolar orthotic.

METHODS

Holes were cut in the study orthoses so that electromagnetic markers could be directly placed on the skin. A 6-foot segment model was used.

OUTCOME MEASUREMENTS

Kinematic and kinetic data were recorded for each patient's initial and follow-up visit (18-month follow-up average, 15-20 months range).

RESULTS

For the SAFO group (gait with AFO), a significant decrease in dorsiflexion was found between the initial and third visit (P = .008). Furthermore, the SAFO group (barefoot gait) had an increased eversion at the midfoot for most of the gait cycle (P < .008). Sagittal forefoot range of motion was reduced for all 3 groups between the barefoot and AFO groups.

CONCLUSION

The use of AFOs long term either maintained or improved foot deformities or dysfunction.

LEVEL OF EVIDENCE

Level II.

Longitudinal change in foot posture in children with cerebral palsy

PURPOSE

Foot deformities are common in children with cerebral palsy (CP), yet the evolution of such deformities is not well documented. We aimed to observe and analyse changes in foot posture during growth in children with CP. Methods We followed 51 children (16 unilateral, 35 bilateral; 37 Gross Motor Function Classification Scale (GMFCS) I/II, 14 III/IV) aged two to 12 years in this level II, IRB-approved prospective longitudinal study. Data after bony foot corrections were excluded. Outcome measures included coronal plane pressure index (CPPI) and pressure impulses from the heel, medial midfoot and medial forefoot. Data were LOESS smoothed and resulting models were compared for significant differences across time using a derived FANOVA method.

RESULTS

The GMFCS I/II group had more foot valgus than typically developing (TD) children until seven years which normalised thereafter. From two to 12 years, GMFCS III/IV children had more foot valgus than TD children. Heel impulse was significantly reduced in both GMFCS groups compared with TD children, and the III/IV group had less heel contact than the I/II group.

CONCLUSIONS

Due to early variability and the tendency for resolving valgus foot posture in children with CP, conservative management of coronal plane foot deformity is suggested in early childhood, especially for children classified as GMFCS I and II.

Effectiveness of surgical and non-surgical management of crouch gait in cerebral palsy: A systematic review

BACKGROUND

Cerebral palsy (CP) is a prevalent group of neuromotor disorders caused by early injury to brain regions or pathways that control movement. Patients with CP exhibit a range of functional motor disabilities and pathologic gait patterns. Crouch gait, characterized by increased knee flexion throughout stance, is a common gait pattern in CP that increases energy costs of walking and contributes to ambulatory decline. Our aim was to perform the first systematic literature review on the effectiveness of interventions utilized to ameliorate crouch gait in CP.

METHODS

Comprehensive searches of five medical databases yielded 38 papers with 30 focused on orthopaedic management.

RESULTS

Evidence supports the use of initial hamstring lengthenings and rectus femoris transfers, where indicated, for improving objective gait measures with limited data on improving gait speed or gross motor function. In contrast, evidence argues against hamstring transfers and revision hamstring lengthening, with recent interest in more technically demanding corrective procedures. Only eight studies evaluated alternatives to surgery, specifically strength training, botulinum toxin or orthoses, with inconsistent and/or short-lived results.

CONCLUSIONS

Although crouch in CP is recognized clinically as a complex multi-joint, multi-planar gait disorder, this review largely failed to identify interventions beyond those which directly address sagittal plane knee motion, indicating a major knowledge gap. Quality of existing data was notably weak, with few studies properly controlled or adequately sized. Outcomes from specific procedures are confounded by multilevel surgeries. Successful longer term strategies to prevent worsening of crouch and subsequent functional decline are needed.

LEVEL OF EVIDENCE

Systematic review.

Segmental kinematic analysis of planovalgus feet during walking in children with cerebral palsy

Pes planovalgus (flatfoot) is a common deformity among children with cerebral palsy. The Milwaukee Foot Model (MFM), a multi-segmental kinematic foot model, which uses radiography to align the underlying bony anatomy with reflective surface markers, was used to evaluate 20 pediatric participants (30feet) with planovalgus secondary to cerebral palsy prior to surgery. Three-dimensional kinematics of the tibia, hindfoot, forefoot, and hallux segments are reported and compared to an age-matched control set of typically-developing children. Most results were consistent with known characteristics of the deformity and showed decreased plantar flexion of the forefoot relative to hindfoot, increased forefoot abduction, and decreased ranges of motion during push-off in the planovalgus group. Interestingly, while forefoot characteristics were uniformly distributed in a common direction in the transverse plane, there was marked variability of forefoot and hindfoot coronal plane and hindfoot transverse plane positioning. The key finding of these data was the radiographic indexing of the MFM was able to show flat feet in cerebral palsy do not always demonstrate more hindfoot eversion than the typically-developing hindfoot. The coronal plane kinematics of the hindfoot show cases planovalgus feet with the hindfoot in inversion, eversion, and neutral. Along with other metrics, the MFM can be a valuable tool for monitoring kinematic deformity, facilitating clinical decision making, and providing a quantitative analysis of surgical effects on the planovalgus foot.

Orthopedic surgery in cerebral palsy: Instructional course lecture

Orthopedic surgery (OS) plays an important role in the management of cerebral palsy (CP). The objectives of OS are to optimize functions and prevent deformity. Newer developments in OS for CP include emphasis on hip surveillance, minimally invasive procedures, use of external fixators instead of plates and screws, better understanding of lever arm dysfunctions (that can only be corrected by bony OS), orthopedic selective spasticity-control surgery, and single-event multilevel lever arm restoration and anti spasticity surgery, which have led to significant improvements in gross motor function and ambulation, especially in spastic quadriplegia, athetosis, and dystonia. The results of OS can be dramatic and life altering for the person with CP and their caregivers if it is performed meticulously by a specialized surgical team, at the appropriate age, for the correct indications, employing sound biomechanical principles and is followed by physician-led, protocol based, intensive, multidisciplinary, institutional rehabilitation, and long term followup. However, OS can be a double-edged sword, and if performed less than optimally, and without the supporting multidisciplinary medical and rehabilitation team, expertise and infrastructure, it often leads to significant functional worsening of the person with CP, including irretrievable loss of previous ambulatory capacity. OS must be integrated into the long term management of the person with CP and should be anticipated and planned at the optimal time and not viewed as a "last resort" intervention or failure of rehabilitation. This instructional course lecture reviews the relevant contemporary principles and techniques of OS in CP.

Rate of Correction and Recurrence of Ankle Valgus in Children Using a Transphyseal Medial Malleolar Screw

BACKGROUND

Transphyseal medial malleolar screw (TMMS) hemiepiphysiodesis is an effective treatment for ankle valgus in children. There is limited evidence on the effect of age and diagnosis on the rate of correction as well as the deformity recurrence after screw removal. The purpose of this study was to determine (1) the rate of correction of ankle valgus after hemiepiphysiodesis using a TMMS, (2) the effects of clinical diagnosis and age at surgery on the rate of correction, and (3) the rate of valgus recurrence after TMMS removal.

METHODS

In this retrospective study we included 16 male and 21 female patients (63 ankles) with an average age at surgery of 11.0 years (range, 5.4 to 14.8 y) who underwent TMMS hemiepiphysiodesis for the treatment of ankle valgus. There was a mean radiographic follow-up of 1.6 years (range, 0.4 to 4.9 y) before screw removal. For subjects who received screw removal (43 ankles), the average time from insertion to removal of the screw was 1.4 years (range, 0.4 to 5.2 y). Valgus deformity was assessed on anteroposterior ankle radiographs by measurement of tibiotalar angle. Linear mixed effects models were used to determine rates of correction and valgus recurrence.

RESULTS

The average rate of correction in tibiotalar angle was 0.37±0.04 degrees per month (P<0.001). Clinical diagnosis and age at surgery significantly affected the amount of postoperative correction in tibiotalar angle (P<0.05). Eighteen of 22 ankles (81.8%) demonstrated recurrence of ankle valgus after screw removal. The average recurrence rate in patients who underwent screw removal was 0.28±0.08 degrees per month (22 ankles, P=0.002).

CONCLUSIONS

This study supports the effectiveness of the TMMS hemiepiphysiodesis for treating pediatric ankle valgus, but the effects of additional skeletal growth should be considered as the ankle may rebound into valgus after correction and screw removal. The results from this study can help with surgical planning to predict the amount of correction that may be achieved depending on underlying diagnosis and age at surgery.

LEVEL OF EVIDENCE

Level IV-retrospective study.

Surgical Treatment Guidelines for Digital Deformity Associated With Intrinsic Muscle Spasticity (Intrinsic Plus Foot) in Adults With Cerebral Palsy

Intrinsic plus foot deformity has primarily been associated with cerebral palsy and involves spastic contracture of the intrinsic musculature with resultant toe deformities. Digital deformity is caused by a dynamic imbalance between the intrinsic muscles in the foot and extrinsic muscles in the lower leg. Spastic contracture of the toes frequently involves curling under of the lesser digits or contracture of the hallux into valgus or plantarflexion deformity. Patients often present with associated pressure ulcers, deformed toenails, shoe or brace fitting challenges, and pain with ambulation or transfers. Four different patterns of intrinsic plus foot deformity have been observed by the authors that likely relate to the different patterns of muscle involvement. Case examples are provided of the 4 patterns of intrinsic plus foot deformity observed, including global intrinsic plus lesser toe deformity, isolated intrinsic plus lesser toe deformity, intrinsic plus hallux valgus deformity, and intrinsic plus hallux flexus deformity. These case examples are presented to demonstrate each type of deformity and our approach for surgical management according to the contracture pattern. The surgical approach has typically involved tenotomy, capsulotomy, or isolated joint fusion. The main goals of surgical treatment are to relieve pain and reduce pressure points through digital realignment in an effort to decrease the risk of pressure sores and allow more effective bracing to ultimately improve the patient's mobility.

Foot and ankle joint movements inside orthoses for children with spastic CP

We compared the ankle joint and foot segment kinematics of pediatric cerebral palsy (CP) participants walking with and without orthoses. A six segment foot model (6SF) was used to track foot motion. Holes were cut in the study orthoses so that electromagnetic markers could be directly placed on the skin. The Hinged Ankle Foot Orthoses (HAFO) allowed a significant increase in ankle dorsiflexion as compared to the barefoot condition during gait, but significantly constrained sagittal forefoot motion and forefoot sagittal range of motion (ROM) (p < 0.01), which may be detrimental. The Solid Ankle Foot Orthoses (SAFO) constrained forefoot ROM as compared to barefoot gait (p < 0.01). The 6SF model did not confirm that the SAFO can control excessive plantarflexion for those with severe plantarflexor spasticity. The supramalleolar orthosis (SMO) significantly (p < 0.01) constrained forefoot ROM as compared to barefoot gait at the beginning and end of the stance phase, which could be detrimental. The SMO had no effects observed in the coronal plane.

Spastic foot and ankle deformities: evaluation and treatment

Spastic foot and ankle deformities can occur from various causes and have profound effects on individuals and society. Presentations can vary clinically and a thorough clinical evaluation, potentially with a dynamic electromyogram, is essential to selecting the most appropriate treatment. Nonoperative treatments, such as orthotics, casting, oral medications, and nerve blocks, can be effective but surgery is indicated if they are no longer effective. Of the various operative procedures to treat this condition, split anterior tibialis tendon transfer and tendo Achilles lengthening are the most commonly performed. Multiple surgical options have been shown to be effective.

Classification of midfoot break using multi-segment foot kinematics and pedobarography

Midfoot break (MFB) is a foot deformity that can occur when ankle dorsiflexion is restricted due to muscle spasticity or contractures, causing abnormal increased motion through the midfoot. MFB has been previously described in terms of forefoot (FF) and hindfoot (HF) motion in the sagittal plane. The purpose of this study was to further classify MFB by describing FF and HF motion in the coronal and transverse planes along with plantar pressures, with the goal of optimizing treatment of this deformity. Three-dimensional foot kinematics were assessed using a multi-segment foot model in children with MFB (n=30) and children with no foot or gait abnormalities (n=30). The MFB group was subdivided into three categories: (1) Pronated MFB, (2) Supinated MFB and (3) Flat Foot MFB. Unique patterns of plantar pressures and foot kinematics were identified for each MFB group. The Pronated MFB group had increased medial midfoot pressures, increased forefoot pronation, and increased external forefoot rotation (forefoot abductus). The Supinated MFB group had increased lateral midfoot pressures, increased forefoot supination, and increased internal forefoot rotation (forefoot adductus). In the Flat Foot MFB group, midfoot pressures were increased and distributed uniformly between the medial and lateral sides, forefoot pronation was increased, and internal forefoot rotation was present. By combining this new information with previously reported methods of measuring sagittal plane kinematics of MFB, it is now possible to characterize midfoot break in terms of severity and foot-floor contact pattern.

Implementation, testing and pilot clinical evaluation of superelastic splints that decrease joint stiffness

The present work aims at demonstrating that a customised choice of shape memory alloy (SMA) composition, thermo-mechanical treatment and shaping can lead to effective rehabilitation devices applicable to sub-acute and chronic spastic paresis in paediatric patients. SMA pseudoelasticity is regarded as a means to implement a corrective action on posture without hindering residual voluntary or reflex mobility of the affected limb. Specific hinges containing NiTi or NiTiNb elements were designed and constructed to transfer pseudoelastic recovery force to fitted splints for the elbow or the ankle joint. The devices were mechanically tested and showed complete stability after 20-100 cycles, and unchanged characteristics after 1000 full-range deflections. Repositioning splints equipped with patient-specific pseudoelastic hinges were prescribed to 25 individuals (aged 7.75 ± 5.40 years) with mild to severe spastic tetraparesis. Clinical and instrumental evaluations were carried out during crossover trials with traditional and pseudoelastic splints. The sequence of treatment steps was randomized for each subject. The results show that, compared to fixed-angle braces, pseudoelastic devices decrease passive joint stiffness while providing the same control on limb posture. Dynamic pseudoelastic braces are therefore an innovative treatment for spastic paresis, which may reduce joint stiffness.

Multilevel surgery for equinus gait in children with spastic diplegic cerebral palsy: medium-term follow-up with gait analysis

BACKGROUND

In children with spastic diplegia, surgery for ankle equinus contracture is associated with a high prevalence of both overcorrection, which may result in a calcaneal deformity and crouch gait, and recurrent equinus contracture, which may require revision surgery. We sought to determine if conservative surgery for equinus gait, in the context of multilevel surgery, could result in the avoidance of overcorrection and crouch gait as well as an acceptable rate of recurrent equinus contracture at the time of medium-term follow-up.

METHODS

This was a retrospective, consecutive cohort study of children with spastic diplegia who had had surgery for equinus gait between 1996 and 2006. All children had distal gastrocnemius recession or differential gastrocnemius-soleus complex lengthening, on one or both sides, as part of single-event multilevel surgery. The primary outcome measures were the Gait Variable Scores (GVS) and Gait Profile Score (GPS) at two time points after surgery.

RESULTS

Forty children with spastic diplegia, Gross Motor Function Classification System (GMFCS) level II or III, were included in this study. There were twenty-five boys and fifteen girls. The mean age was ten years at the time of surgery and seventeen years at the time of final follow-up. The mean postoperative follow-up period was 7.5 years. The mean ankle GVS improved from 18.5° before surgery to 8.7° at the time of short-term follow-up (p < 0.005) and 7.8° at the time of medium-term follow-up. The equinus gait was successfully corrected in the majority of children, with a low rate of overcorrection (2.5%) and a high rate of recurrent equinus (35%), as determined by sagittal ankle kinematics. Mild recurrent equinus was usually well tolerated and conferred some advantages, including contributing to strong coupling at the knee and independence from using an ankle-foot orthosis.

CONCLUSIONS

Surgical treatment for equinus gait in children with spastic diplegia was successful, at a mean of seven years, in the majority of cases when combined with multilevel surgery, orthoses, and rehabilitation. No patient developed crouch gait, and the rate of revision surgery for recurrent equinus was 12.5%.