The Effect of Knee Height Asymmetry on Gait Biomechanics.

BACKGROUND: Though the primary goal for limb length discrepancy (LLD) management is to equalize the leg lengths, symmetry between corresponding long bones is usually not achieved, leading to knee height asymmetry (KHA). To date, there is minimal information on what effect KHA has on gait biomechanics and joint loading. Thus, the purpose of this study is to determine the impact of KHA on gait biomechanics. METHODS: Seventeen subjects with KHA after limb equalizing surgery and 10 healthy controls were enrolled. Subjects participated in 3D gait analysis collected using self-selected speed. Lower extremity kinematics, kinetics, work generated/absorbed, and total work were calculated. Standing lower limb x-rays and scanograms were used to measure LLD and calculate the tibia-to-femur (TF) ratio for each limb. Two sample t tests were used to compare differences in standing LLD, TF ratio, and work between groups. Bivariate correlation using Pearson correlation coefficients was conducted between TF ratio and total mechanical work, as well as between knee height asymmetry indices and total work asymmetry (α=0.05). RESULTS: Among participants, there were no differences between LLD; however, there were differences between TF ratio and knee height asymmetry. We found a nonsignificant relationship between TF ratio and total mechanical work for individual lower extremities. Therefore, the length of individual bones (TF ratio) relative to each other within the individual lower extremity was not associated with the amount of work produced. However, when a difference exists between sides (asymmetry, ie, TF ratio asymmetry), there were associated differences in work (work asymmetry) produced between sides (r=0.54, P=0.003). In other words, greater knee height asymmetry between limbs resulted in more asymmetrical mechanical work during walking. CONCLUSIONS: These findings may have implications for the management of LLD. Asymmetrical total mechanical work could lead to atypical joint loading during gait. Surgeons may want to consider prioritizing achieving knee height symmetry as a postoperative goal when correcting limb length discrepancy. LEVEL OF EVIDENCE: Level III, Case Control Study.

Three-Dimensional Instrumented Gait Analysis for Children With Cerebral Palsy: An Evidence-Based Clinical Practice Guideline.

BACKGROUND: Children with cerebral palsy (CP) who walk have complex gait patterns and deviations often requiring physical therapy (PT)/medical/surgical interventions. Walking in children with CP can be assessed with 3-dimensional instrumented gait analysis (3D-IGA) providing kinematics (joint angles), kinetics (joint moments/powers), and muscle activity. PURPOSE: This clinical practice guideline provides PTs, physicians, and associated clinicians involved in the care of children with CP, with 7 action statements on when and how 3D-IGA can inform clinical assessments and potential interventions. It links the action statement grades with specific levels of evidence based on a critical appraisal of the literature. CONCLUSIONS: This clinical practice guideline addresses 3D-IGA's utility to inform surgical and non-surgical interventions, to identify gait deviations among segments/joints and planes and to evaluate the effectiveness of interventions. Best practice statements provide guidance for clinicians about the preferred characteristics of 3D-IGA laboratories including instrumentation, staffing, and reporting practices.Video Abstract: Supplemental digital content available at http://links.lww.com/PPT/A524.

Instrumented Gait Analysis (IGA) for Management of Children With Cerebral Palsy: A Needs Assessment Survey.

PURPOSE: This needs assessment survey identifies the priorities of the clinical and research communities involved with the use of instrumented gait analysis (IGA) for a clinical practice guideline on IGA use with children with cerebral palsy (CP). METHODS: Thirteen Likert scale questions asked about the importance of topics related to IGA. Other questions addressed respondents' demographics, experience with IGA, patient populations, and gait laboratory characteristics. Several open-ended questions were included and analyzed. RESULTS: The survey was completed by 43 physical therapists and 53 non-physical therapists involved with IGA. More than 90% rated the following as critically or highly important: reliability and validity of IGA to identify gait pathology (94%); ability to longitudinally track gait pathology (93%); use in planning interventions (93%); use in evaluating outcomes (93%); and definition of IGA (90%). CONCLUSIONS AND RECOMMENDATIONS FOR CLINICAL PRACTICE: This needs assessment survey identified the topic priorities of clinicians and practitioners who use IGA for the management of children with CP. These results will guide the development of a clinical practice guideline on the use of IGA for the management of CP.

Do Bisphosphonates Alleviate Pain in Children? A Systematic Review.

PURPOSE OF REVIEW: The goal of this systematic review is to analyze the effectiveness of bisphosphonates (BPs) to treat bone pain in children and adolescents who have diseases with skeletal involvement. RECENT FINDINGS: We included 24 studies (2 randomized controlled trials, 3 non-randomized controlled trials, 10 non-randomized open-label uncontrolled studies, 8 retrospective studies, and 1 study with design not specified). The majority of included studies assessed pain from a unidimensional approach, with pain intensity the most frequently evaluated dimension. Only 38% of studies used validated tools; visual analogue scale was the most frequently employed. BPs were used to alleviate bone pain in a wide variety of pediatrics conditions such as osteogenesis imperfecta, secondary osteoporosis, osteonecrosis related to chemotherapy, chronic non-bacterial osteitis, idiopathic juvenile osteoporosis, unresectable benign bone tumor, and cancer-related pain. Twenty of the 24 studies reported a positive effect of BPs for alleviating pain in different pathologies, but 58% of the studies were categorized as having high risk of bias. Intravenous BPs are helpful in alleviating bone pain in children and adolescents. It is advised that our results be interpreted with caution due to the heterogeneity of the doses used, duration of treatments, and types of pathologies included. In addition, this review shows the paucity of high-quality evidence in the available literature and further research is needed. TRIAL REGISTRATION: Before the completion of this review, the protocol was registered to PROSPERO (International prospective register of systematic reviews), PROSPERO 2020 ID # CRD42020158316. Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020158316.

Quality of life, satisfaction with life, and functional mobility of young adults with arthrogryposis after leaving pediatric care.

The aim of this study was to describe satisfaction and quality of life (QOL) of young adults with arthrogryposis after leaving pediatric care. Twenty-three adults with arthrogryposis multiplex congenital (AMC) followed at a single pediatric orthopedic hospital (average age 23.6 years; range 18-36 years; 9 males, 14 females) completed questionnaires related to demographics, mobility, and activities of daily living. The Patient Reported Outcomes Measure Information System and Satisfaction with Life Scale were utilized to evaluate QOL and life satisfaction. Eighty-three percent reported general health as good/excellent, 30% lived independently, 69% were ambulatory in the community, and 57% were employed. QOL scores for physical function were lower, but other QOL scores were consistent with the general U.S. population. Average pain intensity was mild at 2.6 out of 10, with pain frequently reported in the legs and feet. Fifty-six percent were satisfied to extremely satisfied with life. Five individuals who were dissatisfied with life also reported lower physical function, higher anxiety, depression and fatigue, and pain in multiple joints. Although most young adults with AMC presented with mild pain and limitations in physical function; overall, they reported good QOL. Findings from the current study will help clinicians anticipate the needs of individuals with AMC as they transition from pediatric to adult care.

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

BACKGROUND: Individuals with clubfoot, treated in infancy with either the Ponseti method or comprehensive clubfoot release, often encounter pain as adults. Multiple studies have characterized residual deformity after Ponseti or surgical correction using physical exam, radiographs and pedobarography; however, the relationship between residual foot deformity and pain is not well defined. The purpose of the current study was 2-fold: (1) to evaluate the relationship between foot morphology and pain for young adults treated as infants for idiopathic clubfoot and (2) to describe and compare pedobarographic measures and outcome measures of pain and morphology among surgically treated, Ponseti treated, and typically developing feet. METHODS: We performed a case-control study of individuals treated for clubfoot at 2 separate institutions with either the Ponseti method or comprehensive clubfoot release between 1983 and 1987. All subjects (24 treated with comprehensive clubfoot release, 18 with Ponseti method, and 48 controls) were evaluated using the International Clubfoot Study Group (ICFSG) morphology scoring, dynamic pedobarography, and foot function index surveys. During pedobarography, we collected the subarch angle and arch index as well as the center of pressure progression (COPP) on all subjects. RESULTS: Foot morphology (ICFSG) scores were highly correlated with foot function index pain scores (r=0.43; P<0.001), although the difference in pain scores between the surgical and Ponseti group did not reach significance. The surgical group exhibited greater subarch angle and arch indexes than the Ponseti group, demonstrating a significant difference in morphology, a flatter foot. Finally, we found more abnormalities in foot progression, decreased COPP in the forefoot and increased COPP in the midfoot and hindfoot, in the surgical group compared with controls. CONCLUSIONS: Measures of foot morphology were correlated with pain among all treated for clubfoot. Compared with Ponseti method, comprehensive surgical release lead to greater long-term foot deformity, flatter feet and greater hindfoot loading time. LEVEL OF EVIDENCE: Level III-Therapeutic.

Considering Propulsion Pattern in Therapeutic Outcomes for Children Who Use Manual Wheelchairs.

PURPOSE: Children who use manual wheelchairs encounter pain and injury risks to the upper body. Current literature does not describe how propulsion pattern and physiotherapeutic training methodologies impact response to treatment. METHODS: This study assesses the effect of community-based intensive physical and occupational therapy on functional outcomes over a 7-week period in pediatric manual wheelchair users. RESULTS: Key results include significant joint and musculotendon kinematic differences at the shoulder, improved speed and propulsion effectiveness, and changed propulsion pattern. CONCLUSIONS: Statistics also revealed that propulsion pattern was a predictor of response to therapy, as was weekly therapeutic duration, wheelchair-specific focus by the therapists, and stretching.

Linking the Pediatric Evaluation of Disability Inventory-Computer Adaptive Test (PEDI-CAT) to the International Classification of Function.

PURPOSE: The purpose of the current study was to examine how comprehensively the Pediatric Evaluation of Disability Inventory-Computer Adaptive Test (PEDI-CAT) addresses Activity and Participation components of the International Classification of Functioning, Disability, and Health (ICF). METHODS: Two raters individually linked the 276 items of the PEDI-CAT to the ICF using ICF linking rules, the PEDI-CAT manual, and the ICF browser. Agreement between reviewers was evaluated, and reliability of the linking process was assessed using Cohen's κ. RESULTS: All 9 chapters of Activity and Participation were represented within the PEDI-CAT. The highest frequency of representation was in Mobility (43%) and Self-care (20%) chapters. Agreement between the 2 raters was strong (κ = 0.84). Two items were not definable in the ICF, and 3 linked to Body Function codes. CONCLUSIONS: The PEDI-CAT was strongly representative of the Activities and Participation component of the ICF. The linking process had substantial reliability.

One-Minute Walk and modified Timed Up and Go tests in children with cerebral palsy: performance and minimum clinically important differences.

AIM This prospective multicenter study assessed performance and changes over time, with and without surgical intervention, in the modified Timed Up and Go (mTUG) and One-Minute Walk tests (1MWT) in children with bilateral cerebral palsy (CP). Minimum clinically important differences (MCIDs) were established for these tools. METHOD Two hundred and nineteen participants with bilateral spastic CP (Gross Motor Function Classification System [GMFCS] levels I­III) were evaluated at baseline and 12 months follow-up. The non-surgical group (n=168; 54 females, 114 males; mean age 12y 11mo, [SD 2y 7mo], range 8y 1mo­19y) had no surgical interventions during the study. The surgical group (n=51; 19 females, 32 males; mean age 12y 10mo [SD 2y 8mo] range 8y 2mo­17y 5mo) underwent soft-tissue and/or bony procedures within 12 months from baseline. The mTUG and 1MWT were collected and MCIDs were established from the change scores of the non-surgical group. RESULTS Dependent walkers (GMFCS level III) required more time to complete the mTUG (p≤0.01) than independent walkers (GMFCS levels I and II). For the 1MWT, distance walked decreased with increasing impairment (p≤0.01). 1MWT and mTUG change scores were not significantly different at any GMFCS level for either the surgical or non-surgical groups (p≤0.01). INTERPRETATION Children with varying levels of function (GMFCS level) perform differently on the 1MWT and mTUG. The data and MCID values can assist clinicians in interpreting changes over time and in assessing interventions.

Creating an autoencoder single summary metric to assess gait quality to compare surgical outcomes in children with cerebral palsy: The Shriners Gait Index (SGI).

Gait for individuals with movement disorders varies widely and the variability makes it difficult to assess outcomes of surgical and therapeutic interventions. Although specific joints can be assessed by fewer individual measures, gait depends on multiple parameters making an overall assessment metric difficult to determine. A holistic, summary measure can permit a standard comparison of progress throughout treatments and interventions, and permit more straightforward comparison across varied subjects. We propose a single summary metric (the Shriners Gait Index (SGI)) to represent the quality of gait using a deep learning autoencoder model, which helps to capture the nonlinear statistical relationships among a number of disparate gait metrics. We utilized gait data of 412 individuals under the age of 18 collected from the Motion Analysis Center (MAC) at the Shriners Children's - Chicago. The gait data includes a total of 114 features: temporo-spatial parameters (7), lower extremity kinematics (64), and lower extremity kinetics (43) which were min-max normalized. The developed SGI score captured more than 89% variance of all 144 features using subject-wise cross-validation. Such summary metrics holistically quantify an individual's gait which can then be used to assess the impact of therapeutic interventions. The machine learning approach utilized can be leveraged to create such metrics in a variety of contexts depending on the data available. We also utilized the SGI to compare overall changes to gait after surgery with the goal of improving mobility for individuals with gait disabilities such as Cerebral Palsy.

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.

Barriers and facilitators to implementation of APTA's breast cancer-related lymphedema diagnosis and intervention clinical practice guidelines.

PURPOSE: The purpose of this study was to identify barriers and facilitators influencing implementation of the diagnosis and intervention clinical practice guidelines (CPGs) related to the management of patients with breast cancer-related lymphedema (BCRL). METHODS: A descriptive, cross-sectional web-based survey was conducted. Participants included physical therapists and assistants who were members of the APTA's Academy of Oncologic Physical Therapy and Lymphology Association of North America. Desriptive statisitcs were computed for all demographic and barriers and facilitators data. Individual exploratory factor analyses (EFA) were performed on survey items for both CPGs to identify themes of barriers and facilitators to implementation. RESULTS: A total of 180 respondents completed the survey. 34.9% of respondents read the diagnosis CPG and 22.4% read the intervention CPG. A total of 77.8% reported that they did not have issues in changing their clinical routines and 69.5% did not have resistance working according to CPGs. The EFA resulted in 3 themes for each CPG, accounting for 46% of the variance for the diagnostic CPG and 54% of the variance for the intervention CPG. The 3 themes, clinician characteristics, patient demographics, therapist practice setting and beliefs/values, were weighted differently for each EFA. CONCLUSION: Most respondents did not read either CPG, however, report a willingness to make changes to clinical practice and utilization of CPGs. For those who have attempted to implement the CPGs, this study was the first to identify the barriers and facilitators impacting the implementation of the CPGs related to the management of BCRL. IMPLICATIONS FOR CANCER SURVIVORS: The results will inform the development of targeted implementation strategies to improve access to and adherence to recommendations from the CPGs ultimately improving the efficiency and efficacy of care delivery to patients.

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.

Effect of Starting Posture on Three-Dimensional Jaw and Head Movement.

Objectives: The effect of body posture on movement of the jaw and head has not yet been clearly established. The relationship between jaw and head movement has implications for conditions such as temporomandibular joint disorders which can be associated with neck pain. The purpose of this quasi-experimental study was to examine the effect of starting posture on three-dimensional movement of the jaw and head, and to examine the relationship between head and jaw movement during mouth opening. Material and Methods: Fourteen healthy participants performed jaw opening to comfortable and maximal amounts from three starting body postures (neutral, slumped, upright) while three-dimensional movement of the head, jaw, and trunk was tracked. Separate repeated measures analyses of variance analyses examined the effect of posture on jaw and head rotation and translation, and Pearson product moment correlations examined the relationship between jaw opening and head rotation. Results: Body posture significantly influenced maximal opening but not comfortable opening (P < 0.0033). There was a positive relationship between head extension and maximum opening in an upright posture (r = 0.74, P = 0.006), and head extension and comfortable opening in neutral and upright postures (r = 0.75 to 0.93, P < 0.0033), although there was no relationship between head extension and jaw opening in a slumped posture when opening comfortably. Conclusions: Posture can affect three-dimensional movement of the jaw when opening. Negating the normal head extension that occurs with mouth opening when in a slumped posture has implications for the development of temporomandibular and neck problems in some individuals.

Assignment of local coordinate systems and methods to calculate tibiotalar and subtalar kinematics: A systematic review.

The introduction of biplane fluoroscopy has created the ability to evaluate in vivo motion, enabling six degree-of-freedom measurement of the tibiotalar and subtalar joints. Although the International Society of Biomechanics defines a standard method of assigning local coordinate systems for the ankle joint complex, standards for the tibiotalar and subtalar joints are lacking. The objective of this systematic review was to summarize and appraise the existing literature that (1) defined coordinate systems for the tibia, talus, and/or calcaneus or (2) assigned kinematic definitions for the tibiotalar and/or subtalar joints. A systematic literature search was developed with search results limited to English Language from 2006 through 2020. Articles were screened by two independent reviewers based on title and abstract. Methodological quality was evaluated using a modified assessment tool. Following screening, 52 articles were identified as having met inclusion criteria. Methodological assessment of these articles varied in quality from 61 to 97. Included articles adopted primary methods for defining coordinate systems that included: (1) anatomical coordinate system (ACS) based on individual bone landmarks and/or geometric shapes, (2) orthogonal principal axes, and (3) interactive closest point (ICP) registration. Common methods for calculating kinematics included: (1) joint coordinate system (JCS) to calculate rotation and translation, (2) Cardan/Euler sequences, and (3) inclination and deviation angles for helical angles. The methods each have strengths and weaknesses. This summarized knowledge should provide the basis for the foot and ankle biomechanics community to create an accepted standard for calculating and reporting tibiotalar and subtalar kinematics.

Instrumented gait analysis for management of gait disorders in children with cerebral palsy: A scoping review.

BACKGROUND: The use of Instrumented Gait Analysis (IGA) for the clinical management of individuals with cerebral palsy (CP) has increased in recent years. Previous systematic reviews have been completed to evaluate and summarize the evidence related to the efficacy of IGA in general. However, a focused summary of research studies on IGA for children with CP related gait disorders is needed. RESEARCH QUESTION: The purpose of the current work was to perform a scoping review to describe and categorize the range of existing literature about IGA as applied to the clinical management of children with CP related gait disorders. METHOD: A health sciences librarian developed a search strategy to include four key inclusion criteria of original research study, population included children with CP, study employed IGA, available in English. The available literature was organized into six study categories: reliability and validity, documentation of subgroups or model development, IGA for clinical decision making, effectiveness of treatments that depend on IGA, cost effectiveness, IGA used to evaluate the outcome of surgical, medical or rehabilitation treatment. RESULTS: 909 studies met the inclusion criteria and were placed into the six study categories. 14 % of studies were in reliability and validity, 33 % in subgroups or modeling, 2% in IGA for clinical decision making, 2% in treatments that depend on IGA, 1% in cost effectiveness, and 49 % of studies had IGA used as an outcome measure for treatment. SIGNIFICANCE: This scoping review has documented the wide range, diversity and extent of original research studies investigating the use of IGA for the clinical management of children with CP related gait disorders. The large volume of studies provides a basis for future work to develop a CPG about the use of IGA for the clinical management of children with CP related gait disorders.

The Influence of Sex on Upper Extremity Joint Dynamics in Pediatric Manual Wheelchair Users With Spinal Cord Injury.

INTRODUCTION: Manual wheelchair propulsion is a physically demanding task associated with upper extremity pain and pathology. Shoulder pain is reported in over 25% of pediatric manual wheelchairs users, and this number rises over the lifespan. Upper extremity biomechanics in adults has been associated with shoulder pain and pathology; however, few studies have investigated upper extremity joint dynamics in children. Furthermore, sex may be a critical factor that is currently unexplored with regard to pediatric wheelchair mobility. OBJECTIVES: To investigate differences in upper extremity joint dynamics between pediatric male and female manual wheelchair users with spinal cord injury (SCI) during wheelchair propulsion. METHODS: Novel instrumented wheelchair hand-rims synchronized with optical motion capture were used to acquire upper extremity joint dynamics of 20 pediatric manual wheelchair users with SCI (11 males, 9 females). Thorax, sternoclavicular, acromioclavicular, glenohumeral, elbow, and wrist joint kinematics and kinetics were calculated during wheelchair propulsion. Linear mixed models were used to assess differences between sexes. RESULTS: Females exhibited significantly greater peak forearm pronation (p = .007), normalized wrist lateral force (p = .03), and normalized elbow posterior force (p = .04) than males. Males exhibited significantly greater peak sternoclavicular joint retraction (p < .001) than females. No significant differences between males and females were observed for the glenohumeral joint (p > .012). CONCLUSION: This study found significant differences in upper extremity joint dynamics between sexes during manual wheelchair propulsion. Our results underscore the importance of considering sex when evaluating pediatric wheelchair mobility and developing comprehensive wheelchair training interventions for early detection and prevention of upper extremity pain and pathology.

Effect of Injury Prevention Programs on Lower Extremity Performance in Youth Athletes: A Systematic Review.

BACKGROUND: Understanding how existing youth injury prevention programs affect specific modifiable injury risk factors will inform future program development for youth athletes. OBJECTIVE: To comprehensively evaluate the effects of injury prevention programs on the modifiable intrinsic risk factors associated with lower extremity performance in youth athletes. DATA SOURCES: This systematic review followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A systematic search of the literature was performed using multiple databases (PubMed, EBSCOhost [including CINAHL, Medline, and SPORTDiscus], and PEDro). Secondary references were appraised for relevant articles. Article types included randomized or cluster randomized controlled trials and randomized cohort designs with youth athletes engaged in organized sports, along with outcomes that included at least 1 physical performance outcome measure. STUDY SELECTION: Eight studies met inclusion and exclusion criteria and were reviewed by 2 independent reviewers, with a third consulted in the case of disagreement, which was not needed. STUDY DESIGN: Systematic review. LEVEL OF EVIDENCE: Level 3. DATA EXTRACTION: Included studies underwent review of methodological quality using the Physiotherapy Evidence Database scale. RESULTS: Studies included mixed-sex samples of youth athletes who predominantly participated in soccer at different skill levels. The FIFA 11+ series was the most commonly used injury prevention program. Among studies, the mean percentage of improvement identified was 11.3% for force generation, 5.7% for coordination, 5.2% for posture, and 5.2% for balance. The lowest mean percentage improvement was in speed (2.2%). Endurance was not significantly affected by any of the programs. CONCLUSION: This systematic review shows that injury prevention programs improve several modifiable intrinsic risk factors of lower extremity performance among youth athletes, particularly force generation. However, several intrinsic risk factors were either not significantly affected or specifically addressed by existing programs.

Kinematic foot types in youth with pes planovalgus secondary to cerebral palsy.

BACKGROUND: Kinematic variability of the foot and ankle segments exists during ambulation among individuals with pes planovalgus (PPV) secondary to cerebral palsy (CP). Clinicians have previously recognized such variability through classification schemes to identify subgroups of individuals, but have been unable to identify kinematic foot types. RESEARCH QUESTION: The purpose of this work was to identify kinematic foot types among children with PPV secondary to CP using 3-dimensional multi-segment foot and ankle kinematics during gait as inputs for principal component analysis (PCA) and K-means cluster analysis. METHODS: In a single assessment session, multi-segment foot and ankle kinematics using the Milwaukee Foot Model (MFM) were collected in 31 children/adolescents with pes planovalgus (49 feet) and 16 typically developing (TD) children/adolescents (31 feet). PCA was used as a data reduction technique on 34 kinematic variables. K-means cluster analysis was performed on the identified principal components (PCs) and one-way analyses of variance (ANOVA) was done to determine the effect of subgroup membership on PC scores. RESULTS: The PCA reduced the kinematic variables to seven PCs which accounted for 91% of the total variance. Six distinct kinematic foot types were identified by the cluster analysis. The foot types showed unique kinematic characteristics in both the hindfoot and forefoot. SIGNIFICANCE: This study provides further evidence of kinematic variability in the foot and ankle during ambulation associated with pes planovalgus secondary to CP. The specific contributions of the hindfoot and forefoot would not have been detected using a single segment foot model. The identification of kinematic foot types with unique foot and ankle characteristics has the potential to improve treatment since patients within a foot type are likely to benefit from similar intervention(s).