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.

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.

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.

Gait Characteristics in Youth With Transverse Myelitis.

BACKGROUND: Transverse myelitis (TM) in childhood is a rare disorder characterized by the presence of spinal cord inflammation. Gait difficulty in children with TM is common; however, there is a paucity of literature regarding quantitative assessment of gait in children and adolescents with TM. OBJECTIVES: To characterize gait patterns in a cohort of ambulatory children with TM and age-matched, typically developing peers in order to better understand the functional mobility of patients diagnosed with childhood TM. METHODS: This was a retrospective study of 26 ambulatory pediatric patients with a confirmed diagnosis of TM who had undergone three-dimensional, instrumented gait analysis (3D-IGA) at 3 years of age or older. A group of 38 typically developing children served as a control group. RESULTS: Gait in children with TM was characterized by moderate kinematic deviations as measured by the Gait Deviation Index (GDI) and a crouched gait pattern (p < .001), increased anterior pelvic tilt (p < .001), decreased motion at the knees (p < .001), and a wider base of support (foot progression angle, p < .001). The TM group had a slower walking speed (p < .001), shorter strides (p < .001), and an increased stance phase compared to controls. CONCLUSION: Our study results showed moderate kinematic deviations quantified by the GDI. Overall, the gait pattern in the TM population tested had greater hip and knee flexion with wider foot progression angle. Identification of gait characteristics in children with TM is the first step in predicting changes in gait pattern as they mature over time, which may ultimately allow for targeted intervention to maintain their ambulatory function.

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.

Gait Deviations in Children With Osteogenesis Imperfecta Type I.

BACKGROUND: Osteogenesis imperfecta (OI) is a congenital connective tissue disorder often characterized by orthopaedic complications that impact normal gait. As such, mobility is of particular interest in the OI population as it is associated with multiple aspects of participation and quality of life. The purpose of the current study was to identify and describe common gait deviations in a large sample of individuals with type I OI and speculate the etiology with a goal of improving function. METHODS: Gait analysis was performed on 44 subjects with type I (11.7±3.08 y old) and 30 typically developing controls (9.54±3.1 y old ). Spatial temporal, kinematic, and kinetic gait data were calculated from the Vicon Plug-in-Gait Model. Musculoskeletal modeling of the muscle tendon lengths (MTL) was done in OpenSim 3.3 to evaluate the MTL of the gastrocnemius and gluteus maximus. The gait deviation index, a dimensionless parameter that evaluates the deviation of 9 kinematic gait parameters from a control database, was also calculated. RESULTS: Walking speed, single support time, stride, and step length were lower and double support time was higher in the OI group. The gait deviation index score was lower and external hip rotation angle was higher in the OI group. Peak hip flexor, knee extensor and ankle plantarflexor moments, and power generation at the ankle were lower in the OI group. MTL analysis revealed no significant length discrepancies between the OI group and the typically developing group. CONCLUSIONS: Together, these findings provide a comprehensive description of gait characteristics among a group of individuals with type I OI. Such data inform clinicians about specific gait deviations in this population allowing clinicians to recommend more focused interventions. LEVEL OF EVIDENCE: Level III-case-control study.

Segmental foot and ankle kinematic differences between rectus, planus, and cavus foot types.

The presence of multiple foot types has been used to explain the variability of foot structure observed among healthy adults. These foot types were determined by specific static morphologic features and included rectus (well aligned hindfoot/forefoot), planus (low arched), and cavus (high arched) foot types. Unique biomechanical characteristics of these foot types have been identified but reported differences in segmental foot kinematics among them has been inconsistent due to differences in neutral referencing and evaluation of only select discrete variables. This study used the radiographically-indexed Milwaukee Foot Model to evaluate differences in segmental foot kinematics among healthy adults with rectus, planus, and cavus feet based on the true bony alignment between segments. Based on the definitions of the individual foot types and due to conflicting results in previous literature, the primary study outcome was peak coronal hindfoot position during stance phase. Additionally, locally weighted regression smoothing with alpha-adjusted serial t-test analysis (LAAST) was used to compare these foot types across the entire gait cycle. Average peak hindfoot inversion was -1.6° ± 5.1°, 6.7° ± 3.5°, and 13.6° ± 4.6°, for the Planus, Rectus, and Cavus Groups, respectively. There were significant differences among all comparisons. Differences were observed between the Rectus and Planus Groups and Cavus and Planus Groups throughout the gait cycle. Additionally, the Planus Group had a premature peak velocity toward coronal varus and early transition toward valgus, likely due to a deficient windlass mechanism. This assessment of kinematic data across the gait cycle can help understand differences in dynamic foot function among foot types.

Training Youth With SCI to Improve Efficiency and Biomechanics of Wheelchair Propulsion: A Pilot Study.

Background: Long-term manual wheelchair users are at an increased risk of developing upper extremity (UE) joint pain and injuries due to the repetitive nature of wheelchair propulsion. Youth who sustain spinal cord injuries (SCIs) may be at even greater risk due to the many years they may be wheelchair dependent. There has been a decreasing trend in duration of initial rehabilitation, therefore little time is spent on training of proper wheelchair propulsion. An objective evaluation along with proper training may help prevent the risk of UE pain and injuries over time. Objective: To develop a training program to improve the efficiency and biomechanics of wheelchair propulsion in youth with SCI and evaluate changes made following propulsive training. Methods: Manual wheelchair users between 4 and 21 years old with SCI were recruited from one hospital. Demographic and clinical measures were collected and the subjects completed the Wheelchair User's Shoulder Pain Index. SmartWheel metrics were collected at baseline and following propulsive training on a roller system. Analyses assessed differences in SmartWheel metrics pre and post training. Results: The 23 participants were between 7 and 19 years of age; 57% were male and 69% with paraplegia. Significant improvements were found for SmartWheel metrics of peak backwards force that improved from -3.08 Newtons (N) ± 2.1 pre training to -2.37 N ± 1.9 (p = .041) post training and for push mechanical effectiveness that improved from .575 ± .14 at baseline to .631 ± .17 post training (p = .033). Conclusion: Our results suggest that an objective wheelchair assessment and propulsive training may be a valuable tool for youth with SCI.

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).

Effects of Spinal Fusion for Idiopathic Scoliosis on Lower Body Kinematics During Gait.

STUDY DESIGN: Prospective. OBJECTIVES: The purpose of this study was to compare gait among patients with scoliosis undergoing posterior spinal fusion and instrumentation (PSFI) to typically developing subjects and determine if the location of the lowest instrumented vertebra impacted results. SUMMARY OF BACKGROUND DATA: PSFI is the standard of care for correcting spine deformities, allowing the preservation of body equilibrium while maintaining as many mobile spinal segments as possible. The effect of surgery on joint motion distal to the spine must also be considered. Very few studies have addressed the effect of PSFI on activities such as walking and even fewer address how surgical choice of the lowest instrumented vertebra (LIV) influences possible motion reduction. METHODS: Individuals with scoliosis undergoing PSFI (n = 38) completed gait analysis preoperatively and at postoperative years 1 and 2 along with a control group (n = 24). Comparisons were made with the control group at each time point and between patients fused at L2 and above (L2+) versus L3 and below (L3-). RESULTS: The kinematic results of the AIS group showed some differences when compared to the Control Group, most notably decreased range of motion (ROM) in pelvic tilt and trunk lateral bending. When comparing the LIV groups, only minor differences were observed, and the results showed decreased coronal trunk and pelvis ROM at the one-year visit and decreased hip rotation ROM at the two-year visit in the L3- group. CONCLUSIONS: Patients with AIS showed decreased ROM preoperatively with further decreases postoperatively. These changes remained relatively consistent following the two-year visit, indicating that most kinematic changes occurred in the first year following surgery. Limited functional differences between the two LIV groups may be due to the lack of full ROM used during normal gait, and future work could address tasks that use greater ROM. LEVEL OF EVIDENCE: Level II.

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.

Effect of Surgical Fusion on Volitional Weight-Shifting in Individuals With Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Prospective. OBJECTIVES: The goals of this study were to (1) evaluate the differences in weightbearing symmetry between individuals with adolescent idiopathic scoliosis (AIS) and typically developing controls; (2) observe the effect of posterior spinal fusion and instrumentation (PSFI) on volitional weight-shifting at 1 and 2 years postoperatively; and (3) evaluate whether lowest instrumented fusion level (ie, lowest instrumented vertebra [LIV]) in PSFI has an effect on volitional weight-shifting. SUMMARY OF BACKGROUND DATA: Previous studies have conflicting findings with regard to the effect of scoliosis on postural control tasks as well as the effect of surgery. They have also noted an inconsistent effect of PSFI at different LIVs, with more distal LIVs exhibiting greater reductions in postoperative range of motion. METHODS: The study was designed with an AIS group of 41 patients (8 males and 33 females) with AIS who underwent PSFI, along with a Control Group of 24 age-matched typically developing participants (12 male and 12 female). Both groups performed postural control tasks (static balance and volitional weight-shifting), with the AIS group repeating the tasks at 1 and 2 years postoperatively. RESULTS: At baseline, the AIS group showed increased weightbearing asymmetry than the Control Group (p = .01). The AIS group showed improvements in volitional weight-shifting at 2 years over baseline (p < .01). There was no effect of LIV on volitional weight-shifting by the second postoperative year. CONCLUSIONS: Individuals with AIS have greater weightbearing asymmetry but improved volitional weight-shifting over typically developing controls. PSFI improves volitional weight-shifting beyond preoperative baseline but does not differ significantly by LIV.

Response of Scoliosis in Children with Myelomeningocele to Surgical Release of Tethered Spinal Cord.

Objective: To examine the effect of surgical tethered cord release (TCR) on scoliosis in children with myelomeningocele. Methods: A retrospective review of 65 pediatric patients with myelomeningocele and TCR. The final sample consisted of 20 patients with scoliosis who were managed conservatively after TCR. Results: Average age at TCR was 6.2 years with average follow-up of 3.8 years. Scoliosis of 1 (5%) patient improved, 7 (35%) were stable, and 12 (60%) worsened (≥10°). Fifty percent of patients ultimately required definitive spinal surgery. TCR release delayed definitive spine surgery for an average of 3.2 years. Sixty-four percent of patients with curves less than or equal to 45° had progression of their curves compared to 50% with curves greater than 45°. For patients with curves less than or equal to 45°, curves progressed in 80% of those younger than 10 years as compared to 25% of those older than 10 years. For patients with curves less than or equal to 45°, 43% required definitive spine surgery as opposed to 83% with curves greater than 45°. Level of neurological involvement (ie, lumbar versus thoracic) and age at untethering emerged as factors influencing the effects of TCR for patients with curves less than or equal to 45°. Lumbar curves had more favorable results. Conclusion: Pediatric patients with myelomeningocele and scoliosis should be closely assessed and monitored. A selective approach for youth with lumbosacral level myelomeningocele and progressive curves less than or equal to 45° may result in scoliosis stabilization and avoidance of definitive surgery.

Evaluation of pediatric manual wheelchair mobility using advanced biomechanical methods.

There is minimal research of upper extremity joint dynamics during pediatric wheelchair mobility despite the large number of children using manual wheelchairs. Special concern arises with the pediatric population, particularly in regard to the longer duration of wheelchair use, joint integrity, participation and community integration, and transitional care into adulthood. This study seeks to provide evaluation methods for characterizing the biomechanics of wheelchair use by children with spinal cord injury (SCI). Twelve subjects with SCI underwent motion analysis while they propelled their wheelchair at a self-selected speed and propulsion pattern. Upper extremity joint kinematics, forces, and moments were computed using inverse dynamics methods with our custom model. The glenohumeral joint displayed the largest average range of motion (ROM) at 47.1° in the sagittal plane and the largest average superiorly and anteriorly directed joint forces of 6.1% BW and 6.5% BW, respectively. The largest joint moments were 1.4% body weight times height (BW × H) of elbow flexion and 1.2% BW × H of glenohumeral joint extension. Pediatric manual wheelchair users demonstrating these high joint demands may be at risk for pain and upper limb injuries. These evaluation methods may be a useful tool for clinicians and therapists for pediatric wheelchair prescription and training.

Kinematic foot types in youth with equinovarus secondary to hemiplegia.

BACKGROUND: Elevated kinematic variability of the foot and ankle segments exists during gait among individuals with equinovarus secondary to hemiplegic cerebral palsy (CP). Clinicians have previously addressed such variability by developing classification schemes to identify subgroups of individuals based on their kinematics. OBJECTIVE: To identify kinematic subgroups among youth with equinovarus secondary to CP using 3-dimensional multi-segment foot and ankle kinematics during locomotion 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 24 children/adolescents with equinovarus and 20 typically developing children/adolescents. RESULTS: PCA was used as a data reduction technique on 40 variables. K-means cluster analysis was performed on the first six principal components (PCs) which accounted for 92% of the variance of the dataset. The PCs described the location and plane of involvement in the foot and ankle. Five distinct kinematic subgroups were identified using K-means clustering. Participants with equinovarus presented with variable involvement ranging from primary hindfoot or forefoot deviations to deformtiy that included both segments in multiple planes. CONCLUSION: This study provides further evidence of the variability in foot characteristics associated with equinovarus secondary to hemiplegic CP. These findings would not have been detected using a single segment foot model. The identification of multiple kinematic subgroups with unique foot and ankle characteristics has the potential to improve treatment since similar patients within a subgroup are likely to benefit from the same intervention(s).

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

BACKGROUND: Clubfoot can be treated nonoperatively, most commonly using a Ponseti approach, or surgically, most often with a comprehensive clubfoot release. Little is known about how these approaches compare with one another at longer term, or how patients treated with these approaches differ in terms of foot function, foot biomechanics, or quality-of-life from individuals who did not have clubfoot as a child. QUESTIONS/PURPOSES: We compared (1) focused physical and radiographic examinations, (2) gait analysis, and (3) quality-of-life measures at long-term followup between groups of adult patients with clubfoot treated either with the Ponseti method of nonsurgical management or a comprehensive surgical release through a Cincinnati incision, and compared these two groups with a control group without clubfoot. METHODS: This was a case control study of individuals treated for clubfoot at two separate institutions with different methods of treatment between 1983 to 1987. One hospital used only the Ponseti method and the other mainly used a comprehensive clubfoot release. There were 42 adults (24 treated surgically, 18 treated with Ponseti method) with isolated clubfoot along with 48 healthy control subjects who agreed to participate in a detailed analysis of physical function, foot biomechanics, and quality-of-life metrics. RESULTS: Both treatment groups had diminished strength and motion compared with the control subjects on physical examination measures; however, the Ponseti group had significantly greater ankle plantar flexion ROM (p < 0.001), greater ankle plantar flexor (p = 0.031) and evertor (p = 0.012) strength, and a decreased incidence of osteoarthritis in the ankle and foot compared with the surgical group. During gait the surgical group had reduced peak ankle plantar flexion (p = 0.002), and reduced sagittal plane hindfoot (p = 0.009) and forefoot (p = 0.008) ROM during the preswing phase compared with the Ponseti group. The surgical group had the lowest overall ankle power generation during push off compared with the control subjects (p = 0.002). Outcome tools revealed elevated pain levels in the surgical group compared with the Ponseti group (p = 0.008) and lower scores for physical function and quality-of-life for both clubfoot groups compared with age-range matched control subjects (p = 0.01). CONCLUSIONS: Although individuals in each treatment group experienced pain, weakness, and reduced ROM, they were highly functional into early adulthood. As adults the Ponseti group fared better than the surgically treated group because of advantages including increased ROM observed at the physical examination and during gait, greater strength, and less arthritis. This study supports efforts to correct clubfoot with Ponseti casting and minimizing surgery to the joints, and highlights the need to improve methods that promote ROM and strength which are important for adult function. LEVEL OF EVIDENCE: Level III, prognostic study.

Upper extremity biomechanics of children with spinal cord injury during wheelchair mobility.

While much work is being done evaluating the upper extremity joint dynamics of adult manual wheelchair propulsion, limited work has examined the pediatric population of manual wheelchair users. Our group used a custom pediatric biomechanical model to characterize the upper extremity joint dynamics of 12 children and adolescents with spinal cord injury (SCI) during wheelchair propulsion. Results show that loading appears to agree with that of adult manual wheelchair users, with the highest loading primarily seen at the glenohumeral joint. This is concerning due to the increased time of wheelchair use in the pediatric population and the impact of this loading during developmental years. This research may assist clinicians with improved mobility assessment methods, wheelchair prescription, training, and long-term care of children with orthopaedic disabilities.

Effect of Lowest Instrumented Vertebra on Trunk Mobility in Patients With Adolescent Idiopathic Scoliosis Undergoing a Posterior Spinal Fusion.

STUDY DESIGN: Prospective. OBJECTIVES: The goal of this study was to evaluate the effect of posterior spinal fusion surgery terminating at different lowest instrumented vertebrae (LIV) on trunk mobility in individuals with adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA: Posterior spinal fusion with instrumentation is the standard surgical technique employed in AIS for correcting spine deformities with Cobb angles exceeding 50°. Surgical correction of curve deformity reduces trunk mobility and range of motion. However, conflicting findings from previous studies investigating the impact of different LIV levels on the reduction in trunk mobility after surgery have been reported. METHODS: The study was designed as a prospective study with 47 patients (7 males and 40 females) with AIS who underwent posterior spinal fusion. Patients were classified into 5 groups based on their surgical LIV level (ie, T12, L1, L2, L3, and L4). Trunk flexion-extension (sagittal plane), lateral bending (coronal plane), and axial rotation (transverse plane) kinematics were assessed during preoperative, 1 year postoperative, and 2 years postoperative evaluation visits. RESULTS: There were postoperative reductions of 41%, 51%, and 59% in trunk range of motion in the sagittal, coronal, and transverse planes, respectively (p < .0001). A trend toward greater postoperative reductions in peak forward flexion at more distal LIVs was observed (p = .04). CONCLUSIONS: Fusion reduces trunk mobility in the sagittal, coronal, and transverse planes. More distal LIV fusions limit peak forward flexion to a greater extent which is considered clinically significant. After fusion, the reductions seen in axial rotation, lateral bending, and backward extension do not differ significantly at more distal LIVs.

Evaluation of cast creep occurring during simulated clubfoot correction.

The Ponseti method is a widely accepted and highly successful conservative treatment of pediatric clubfoot involving weekly manipulations and cast applications. Qualitative assessments have indicated the potential success of the technique with cast materials other than standard plaster of Paris. However, guidelines for clubfoot correction based on the mechanical response of these materials have yet to be investigated. The current study sought to characterize and compare the ability of three standard cast materials to maintain the Ponseti-corrected foot position by evaluating cast creep response. A dynamic cast testing device, built to model clubfoot correction, was wrapped in plaster of Paris, semi-rigid fiberglass, and rigid fiberglass. Three-dimensional motion responses to two joint stiffnesses were recorded. Rotational creep displacement and linearity of the limb-cast composite were analyzed. Minimal change in position over time was found for all materials. Among cast materials, the rotational creep displacement was significantly different (p < 0.0001). The most creep displacement occurred in the plaster of Paris (2.0°), then the semi-rigid fiberglass (1.0°), and then the rigid fiberglass (0.4°). Torque magnitude did not affect creep displacement response. Analysis of normalized rotation showed quasi-linear viscoelastic behavior. This study provided a mechanical evaluation of cast material performance as used for clubfoot correction. Creep displacement dependence on cast material and insensitivity to torque were discovered. This information may provide a quantitative and mechanical basis for future innovations for clubfoot care.

Effect of fine wire electrode insertion on gait patterns in children with hemiplegic cerebral palsy.

BACKGROUND: Fine wire electromyography (EMG) is commonly used for surgical decision making in equinovarus foot deformity. However, this invasive technique may have the unwanted effect of altering the gait of children with cerebral palsy (CP). The purpose of this study was to determine if fine wire insertion into the posterior tibialis muscle affects temporal-spatial parameters and hindfoot kinematics during gait in children with equinovarus secondary to hemiplegic CP. METHODS: 12 children with hemiplegic CP who presented with an equinovarus foot (mean age 12.5 yrs, four right-sided, eight left-sided) were recruited. Temporal-spatial parameters and 3-D segmental foot and ankle kinematic gait data were collected utilizing standard gait analysis and the Milwaukee Foot Model (MFM). Three representative trials with and without fine wire electrode insertion were compared to determine the effect of electrode placement in the posterior tibialis on temporal spatial-parameters and hindfoot sagittal, coronal and transverse plane kinematic peaks, timing of kinematic peaks, and excursions. RESULTS: No significant differences in any temporal-spatial or kinematic parameters were observed between "with wire" and "without wire" conditions. Strong correlations were observed among the gait parameters, with the exception of cadence, for the two conditions. DISCUSSION: Fine wire insertion into the posterior tibialis had no measurable effect on the gait of individuals with equinovarus secondary to hemiplegic CP. This suggests that the simultaneous collection of segmental foot and ankle kinematics and fine wire EMG data of the posterior tibialis is acceptable for surgical decision making in this patient population.