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.

Epidemiology, aetiology, interventions and genomics in children with arthrogryposis multiplex congenita: protocol for a multisite registry.

INTRODUCTION: Arthrogryposis multiplex congenita (AMC) is an umbrella term including hundreds of conditions with the common clinical manifestation of multiple congenital contractures. AMC affects 1 in 3000 live births and is caused by lack of movement in utero. To understand the long-term needs of individuals diagnosed with a rare condition, it is essential to know the prevalence, aetiology and functional outcomes in a large sample. The development and implementation of a multicentre registry is critical to gather this data. This registry aims to improve health through genetic and outcomes research, and ultimately identify new therapeutic targets and diagnostics for treating children with AMC. METHODS AND ANALYSIS: Participants for the AMC registry will be recruited from seven orthopaedic hospitals in North America. Enrollment occurs in two phases; Part 1 focuses on epidemiology, aetiology and interventions. For this part, retrospective and cross-sectional data will be collected using a combination of patient-reported outcomes and clinical measures. Part 2 focuses on core subset of the study team, including a geneticist and bioinformatician, identifying causative genes and linking the phenotype to genotype via whole genome sequencing to identify genetic variants and correlating these findings with pedigree, photographs and clinical information. Descriptive analyses on the sample of 400 participants and logistic regression models to evaluate relationships between outcomes will be conducted. ETHICS AND DISSEMINATION: Ethical approval has been granted from corresponding governing bodies in North America. Dissemination of findings will occur via traditional platforms (conferences, manuscripts) for the scientific community. Other modalities will be employed to ensure that all stakeholders, including youth, families and patient support groups, may be provided with findings derived from the registry. Ensuring the findings are circulated to a maximum amount of interested parties will ensure that the registry can continue to serve as a platform for hypothesis-driven research and further advancement for AMC.

Jones Fracture: A Late Sequelae of Undercorrected or Recurrent Congenital Talipes Equinovarus: A Report of 2 Cases.

CASE: We present 2 cases in which patients previously treated for congenital talipes equinovarus (CTEV) presented with residual cavovarus deformity and lateral foot pain and were found to have Jones fractures. Both patients were indicated for surgical correction of their residual cavovarus deformity, although neither elected to proceed. These 2 patients were treated conservatively for their fractures with cast immobilization. At the final follow-up, both were clinically and radiographically healed. CONCLUSION: Residual cavovarus foot deformities after the treatment of CTEV are at risk for proximal fifth metatarsal or Jones fractures. Although conservative management may lead to healing of these fractures, the underlying stresses persist after conservative management increasing the risk for recurrent fracture. Correction of the residual deformity should be the main goal.

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.

Treatment and outcomes of arthrogryposis in the lower extremity.

In this multiauthored article, the management of lower limb deformities in children with arthrogryposis (specifically Amyoplasia) is discussed. Separate sections address various hip, knee, foot, and ankle issues as well as orthotic treatment and functional outcomes. The importance of very early and aggressive management of these deformities in the form of intensive physiotherapy (with its various modalities) and bracing is emphasized. Surgical techniques commonly used in the management of these conditions are outlined. The central role of a multidisciplinary approach involving all stakeholders, especially the families, is also discussed. Furthermore, the key role of functional outcome tools, specifically patient reported outcomes, in the continuous monitoring and evaluation of these deformities is addressed. Children with arthrogryposis present multiple problems that necessitate a multidisciplinary approach. Specific guidelines are necessary in order to inform patients, families, and health care givers on the best approach to address these complex conditions.

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.

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.

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).

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.

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.

Dysplasia epiphysealis hemimelica of the knee: an unusual presentation with intra-articular loose bodies and literature review.

Dysplasia epiphysealis hemimelica (DEH) is a rare disease characterized by the formation of osteochondromas asymmetrically at the epiphysis of extremities, typically involving the ankle and the knee. It progresses during childhood and presents with limited range of motion, swelling, and angular deformities. A 9-year-old boy with a 7-year history of DEH and previous removal of ankle osteochondromas presented with acute knee pain, swelling, and limited range of motion. A clinical, radiographic, and literature review of this case was conducted to better describe this occurrence. On the basis of clinical and radiographic analyses, loose bodies were found to be originating from intra-articular osteochondromas. Because of the patient's symptoms, an exploratory arthroscopy was performed to further assess the formations, and the loose bodies were removed. After the procedure, the patient's function and symptoms improved. To the best of our knowledge, this is the first report of a case that identifies a complication of DEH to be loose bodies with a clear etiology and acute progression of symptoms. The possibility of loose bodies should be considered when examining a patient diagnosed with DEH with acute progression of symptoms. Level of evidence level IV, case report.

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.

Congenital tibial dysplasia with lateral bowing and duplication of hallux: case presentations.

This article reports on two children with congenital unilateral tibial dysplasia with lateral bowing with no associated sagittal plane deformity. In both cases, it is associated with ipsilateral duplication of the hallux. Long-term follow-up of the patients showed spontaneous, almost complete resolution of the bowing without progressing into fracture or pseudoarthrosis. Leg length discrepancy appeared to be the only orthopedic sequela related to this phenomenon.

Creep evaluation of (orthotic) cast materials during simulated clubfoot correction.

The Ponseti method is a widely accepted and highly successful conservative treatment of pediatric clubfoot that relies on weekly manipulations and cast applications. However, the material behavior of the cast in the Ponseti technique has not been investigated. The current study sought to characterize the ability of two standard casting materials to maintain the Ponseti corrected foot position by evaluating creep response. A dynamic cast testing device (DCTD) was built to simulate a typical pediatric clubfoot. Semi-rigid fiberglass and rigid fiberglass casting materials were applied to the device, and the rotational creep was measured at various constant torques. The movement was measured using a 3D motion capture system. A 2-way ANOVA was performed on the creep displacement data at a significance level of 0.05. Among cast materials, the rotational creep displacement was found to be significantly different (p-values ≪ 0.001). The most creep displacement occurs in the semi-rigid fiberglass (approximately 1.0 degrees), then the rigid fiberglass (approximately 0.4 degrees). There was no effect of torque magnitude on the creep displacement. All materials maintained the corrected position with minimal change in position over time.

Classification of Legg-Calvé-Perthes disease.

Although the etiology of Perthes disease remains unknown 100 years after its first description, there are many articles that describe the disease course, final outcome, and results of treatment. A system of classification of the extent and severity of the disease is essential to understanding variability of Perthes, and along with the age of the patient when first affected, is useful in predicting long-term outcomes. Published reports of treatment strategies and their success depend on effective classification of the disease severity and radiographic result at final follow-up concerning head sphericity, congruency with the acetabulum, and arthritis. This article reviews published articles that contain classification systems and details presently used systems that are helpful in understanding and in treating Perthes.

Kyphectomy in children with myelomeningocele.

BACKGROUND: Patients with myelomeningocele and rigid lumbar and thoracolumbar kyphosis face substantial functional difficulties with sitting and lying supine and are prone to skin breakdown over the gibbus and risk of infection. Kyphectomy, along with cordotomy and segmental spinal instrumentation down to the pelvis, is one alternative that can provide reliable correction of the deformity but also can maintain that correction over a period of time. QUESTIONS/PURPOSES: We determined the fusion rates, deformity correction and maintenance, and perioperative complications of kyphectomy with long segmental spinal instrumentation using the Warner and Fackler technique. METHODS: We retrospectively reviewed the charts and radiographs of 33 patients with myelomeningocele who had kyphectomy with segmental spinal instrumentation down to the pelvis between 1991 and 2006. The average age at surgery was 7.6 years (range, 3-19 years). Twenty-one patients had a minimum 2-year followup (average, 7.0 years; range, 2.4-15.7 years). RESULTS: The average preoperative kyphosis of 124° (range, 75°-210°) improved at last followup to 22° (range, 3°-55°) with an average correction of 81% (range, 59%-98%). We identified 17 postoperative complications. Wound and skin complications were most common; 11 secondary surgeries were performed in 10 patients. CONCLUSIONS: Surgery for myelomeningocele kyphosis is technically demanding and carries substantial risk. Kyphectomy and posterior spinal fusion and instrumentation with the Warner and Fackler technique allow correction and maintenance of sagittal alignment.

How does participation of youth with spina bifida vary by age?

BACKGROUND: Youth with disabilities are at risk for decreased participation in community activities. However, little is known about participation at different developmental periods of childhood and adolescence among youth with spina bifida (SB) or whether child, family, and SB-associated factors influence participation. QUESTIONS/PURPOSES: Our cross-sectional study examined participation among youth with SB and assessed how participation differs between youth ages 2-5, 6-12, and 13-18; how participation relates to child (gender) and family (caregiver marital status, education, and employment) characteristics; and how participation relates to SB-related factors (motor level, hydrocephalus, ambulation, medical issues, and bladder/bowel needs). PATIENTS AND METHODS: Sixty-three youth ages 2-18 years and/or their caregivers completed age-appropriate measures of participation for youth with disabilities. The patients had an average age of 9.52 years (SD = 5.22), 83% had a shunt, 34% had a motor level of L2 or higher, and 66% L3 or lower. RESULTS: A comparison of youth ages 2-5 (n = 19), 6-12 (n = 21), and 13-18 (n = 23) revealed older youth participated less in recreational, physical, and skill-based activities. Caregiver employment facilitated participation in social activities. Youth who did not have a shunt participated more often in physical and skill-based activities. Youth without recent major medical issues participated more often in physical and social activities. More caregivers reported bladder and bowel needs as barriers to participation for youth ages 6-12 than those ages 2-5 or 13-18. CONCLUSIONS: Participation of youth with SB varies by age and across child and caregiver factors and should be understood in a developmental and situational context.

Activity level, functional health, and quality of life of children with myelomeningocele as perceived by parents.

BACKGROUND: To provide the best health care for individuals with myelomeningocele (MM), clinicians and researchers need to understand their health and functional status as well as quality of life. The literature is mixed regarding the relationship between motor level and health-related quality of life (HRQOL) for these individuals. QUESTIONS/PURPOSES: We compared the HRQOL of children with MM at the L2 and above and L3-5 motor level and to demonstrate how having a shunt, age, and body mass index affect HRQOL instruments for these two motor level groups. METHODS: We recruited 50 patients with MM (24 male, 26 female) with a mean age of 11.5 years (range, 5-18 years) and motor levels of L2 and above (n = 15) and L3-5 (n = 35). Guardians were interviewed using standardized functional and HRQOL tools (the Pediatric Quality of Life and the Pediatric Outcomes Data Collection Instrument); height, weight, presence of a shunt, ambulatory level, and body mass index were also collected. RESULTS: We found a decreased HRQOL score for children with MM in the L2 and above motor level compared with those in the L3-5 motor level group. HRQOL had no correlation with body mass index and limited correlation with age. The presence of a shunt correlated with a decreased HRQOL. CONCLUSIONS: Children with MM had deficits in HRQOL and that was associated with neurologic level and presence of a shunt.

[Upper extremity kinetics and energy expenditure during walker-assisted gait in children with cerebral palsy]. / Beyin felçli çocuklarda yürüteç kullanimi sirasinda üst ekstremite kinetikleri ve enerji tüketimi.

OBJECTIVES: We evaluated the relationships between upper extremity (UE) kinetics and the energy expenditure index during anterior and posterior walker-assisted gait in children with spastic diplegic cerebral palsy (CP). METHODS: Ten children (3 boys, 7 girls; mean age 12.1 years; range 8 to 18 years) with spastic diplegic CP, who ambulated with a walker underwent gait analyses that included UE kinematics and kinetics. Upper extremity kinetics were obtained using instrumented walker handles. Energy expenditure index was obtained using the heart rate method (EEIHR) by subtracting resting heart rate from walking heart rate, and dividing by the walking speed. Correlations were sought between the kinetic variables and the EEIHR and temporal and stride parameters. RESULTS: In general, anterior walker use was associated with a higher EEIHR. Several kinetic variables correlated well with temporal and stride parameters, as well as the EEIHR. All of the significant correlations (r>0.80; p<0.005) occurred during anterior walker use and involved joint reaction forces (JRF) rather than moments. Some variables showed multiple strong correlations during anterior walker use, including the medial JRF in the wrist, the posterior JRF in the elbow, and the inferior and superior JRFs in the shoulder. CONCLUSION: The observed correlations may indicate a relationship between the force used to advance the body forward within the walker frame and an increased EEIHR. More work is needed to refine the correlations, and to explore relationships with other variables, including the joint kinematics.