Correlation of transverse rotation of the spine using surface topography and 3D reconstructive radiography in children with idiopathic scoliosis.

PURPOSE: The relationship between axial surface rotation (ASR) measured by surface topography (ST) and axial vertebral rotation (AVR) measured by radiography in the transverse plane is not well defined. This study aimed to: (1) quantify ASR and AVR patterns and their magnitudes from T1 to L5; (2) determine the correlation or agreement between the ASR and AVR; and (3) investigate the relationship between axial rotation differences (ASR-AVR) and major Cobb angle. METHODS: This is a retrospective study evaluating patients (age 8-18) with IS or spinal asymmetry with both radiographic and ST measurements. Demographics, descriptive analysis, and correlations and agreements between ASR and AVR were evaluated. A piecewise linear regression model was further created to relate rotational differences to Cobb angle. RESULTS: Fifty-two subjects met inclusion criteria. Mean age was 14.1 ± 1.7 and 39 (75%) were female. Looking at patterns, AVR had maximal rotation at T8, while ASR had maximal rotation at T11 (r = 0.35, P = .006). Cobb angle was 24.1° ± 13.3° with AVR of - 1° ± 4.6° and scoliotic angle was 20.9° ± 11.5° with ASR of - 2.3° ± 6.6°. (ASR-AVR) vs Cobb angle was found to be very weakly correlated with a curve of less than 38.8° (r = 0.15, P = .001). CONCLUSION: Our preliminary findings support that ASR measured by ST has a weak correlation with estimation of AVR by 3D radiographic reconstruction. This correlation may further help us to understand the application of transverse rotation in some clinical scenarios such as specific casting manipulation, padding mechanism in brace, and surgical correction of rib deformity.

3D Back Contour Metrics in Predicting Idiopathic Scoliosis Progression: Retrospective Cohort Analysis, Case Series Report and Proof of Concept.

Adolescent Idiopathic Scoliosis is a 3D spinal deformity commonly characterized by serial radiographs. Patients with AIS may have increased average radiation exposure compared to unaffected patients and thus may be implicated with a modest increase in cancer risk. To minimize lifetime radiation exposure, alternative imaging modalities such as surface topography are being explored. Surface topography (ST) uses a camera to map anatomic landmarks of the spine and contours of the back to create software-generated spine models. ST has previously shown good correlation to radiographic measures. In this study, we sought to use ST in the creation of a risk stratification model. A total of 38 patients met the inclusion criteria for curve progression prediction. Scoliotic curves were classified as progressing, stabilized, or improving, and a predictive model was created using the proportional odds logistic modeling. The results showed that surface topography was able to moderately appraise scoliosis curvatures when compared to radiographs. The predictive model, using demographic and surface topography measurements, was able to account for 86.9% of the variability in the future Cobb angle. Additionally, attempts at classification of curve progression, stabilization, or improvement were accurately predicted 27/38 times, 71%. These results provide a basis for the creation of a clinical tool in the tracking and prediction of scoliosis progression in order to reduce the number of X-rays required.

Prophylactic Spinal Cord Untethering in Children with Spinal Dysraphism Undergoing Thoracolumbar Fusion for Scoliosis.

BACKGROUND: It remains unclear whether spinal cord untethering is necessary to reduce the chances of neurologic decline in children with myelomeningocele and complex closed spinal dysraphism who undergo thoracolumbar fusion for scoliosis. We sought to determine the neurologic and functional outcomes of children with spinal dysraphism undergoing spinal fusion for scoliosis with and without prophylactic spinal cord untethering. METHODS: Retrospective, single-center review of patients with spinal dysraphism treated with thoracolumbar fusion over the last 10 years (2009-2019) with or without prophylactic spinal cord untethering. RESULTS: Seventeen patients with myelomeningocele and complex closed spinal dysraphism underwent spinal fusion for scoliosis. Mean age at time of surgery was 13.9 years. Prophylactic spinal cord untethering was performed in 8 of 17 (47%) patients. The change in Cobb angle after surgery was similar between the 2 groups (19.4° untethered vs. 19.9° no untethering). The ambulatory status was similar between the groups, with 37% of the untethered cohort and 44% of the non-untethered cohort being community or household ambulators. There were no changes in intraoperative motor or sensory evoked potentials in any patient during fusion surgery. No patient had a change in motor level or ambulatory status after scoliosis surgery. CONCLUSIONS: Our data suggest that prophylactic spinal cord untethering in children with spinal dysraphism undergoing thoracolumbar fusion for scoliosis may not be necessary in patients with moderate curvatures. Our conclusions are limited by the small sample size. A larger review of registry data may yield more powerful conclusions on the necessity of prophylactic spinal cord untethering in this patient population.

Biomechanical Effects of Thoracolumbosacral Orthosis Design Features on 3D Correction in Adolescent Idiopathic Scoliosis: A Comprehensive Multicenter Study.

STUDY DESIGN: Multicenter numerical study. OBJECTIVE: To biomechanically analyze and compare various passive correction features of braces, designed by several centers with diverse practices, for three-dimensional (3D) correction of adolescent idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: A wide variety of brace designs exist, but their biomechanical effectiveness is not clearly understood. Many studies have reported brace treatment correction potential with various degrees of control, making the objective comparison of correction mechanisms difficult. A Finite Element Model simulating the immediate in-brace corrective effects has been developed and allows to comprehensively assess the biomechanics of different brace designs. METHODS: Expert clinical teams (one orthotist and one orthopedist) from six centers in five countries participated in the study. For six scoliosis cases with different curve types respecting SRS criteria, the teams designed two braces according to their treatment protocol. Finite Element Model simulations were performed to compute immediate in-brace 3D correction and skin-to-brace pressures. All braces were randomized and labeled according to 21 design features derived from Society on Scoliosis Orthopaedic and Rehabilitation Treatment proposed descriptors, including positioning of pressure points, orientation of push vectors, and sagittal design. Simulated in brace 3D corrections were compared for each design feature class using ANOVAs and linear regressions (significance P ≤ 0.05). RESULTS: Seventy-two braces were tested, with significant variety in the design approaches. Pressure points at the apical vertebra level corrected the main thoracic curve better than more caudal locations. Braces with ventral support flattened the lumbar lordosis. Lateral and ventral skin-to-brace pressures were correlated with changes in thoracolumbar/lumbar Cobb and lumbar lordosis (r =- 0.53, r = - 0.54). Upper straps positioned above T10 corrected the main thoracic Cobb better than those placed lower. CONCLUSIONS: The corrective features of various scoliosis braces were objectively compared in a systematic approach with minimal biases and variability in test parameters, providing a better biomechanical understanding of individual passive mechanisms' contribution to 3D correction.

Nonoperative management of adolescent idiopathic scoliosis (AIS) using braces.

This review presents the state of the art according to the current evidence on nonoperative treatment for adolescent idiopathic scoliosis, focusing on bracing. The definition of braces for the treatment of adolescent idiopathic scoliosis and a short history are provided. The analysis includes biomechanics, types, existing classifications, indications for treatment, time of brace wear and weaning, adherence, three-dimensional modeling, use of ultrasound imaging for bracing, management of treatment, issue of immediate in-brace correction, and documentation of the outcomes usually assessed for brace treatment, including the quality-of-life issues. According to the current evidence, there are two randomized control trials in favor of bracing. There are insufficient data on the superiority of one brace over another, although it is possible to classify and grade braces for efficacy from nonrigid to rigid and very rigid. Nevertheless, there is consensus on patients' management on the need for teamwork focusing on adherence to treatment, acceptability, and family and patient involvement.

Long-term follow-up of children with a surgically treated clubfoot: Assessing the multi-segment-foot motions, dynamic plantar pressures, and functional outcomes.

OBJECTIVE: The purpose of this study was to compare surgically treated clubfoot with typically developing (TD) children using plantar pressure, multi-segment-foot kinematic analysis, and multiple functional outcomes in comprehensive and long-term study. Methods: 26 patients with 45 clubfeet and 23 TD children with 45 normal feet were evaluated. Most clubfoot patients had a complete subtalar release and a few patients had a posterior medial-lateral release at the mean age of 5 years and 6 months. The mean age at follow-up for clubfoot was 12 years and 5 months. Subjects underwent physical and radiographic examination, plantar pressure analysis, multi-segment-foot motion analysis, AAOS Foot & Ankle Questionnaire (AAOS-FAQ), the Pediatric Outcomes Data Collection Instrument (PODCI), and the Child Behavior Checklist (CBCL). RESULTS: Clubfoot patients scored significantly worse than TD on the AAOS-FAQ (90.9 vs.99.9 for pain and comfort), the CBCL Problems scale (23.1 vs.6.3), and several subscales of the PODCI (86.5 vs.96.7 for Sports and Physical Functioning) (P<0.05). Peak pressure at the lateral heel (25.6 vs.29.6 N/cm2), contact area at the 1 st metatarsal head (1 st MT) (6.0 vs. 7.2 cm2) and the pressure time integral at the 1 st MT (5.2 vs. 11.0 N/cm2 ∗ s) were significantly lower for the clubfoot group compared to the TD foot group (P<0.05). Maximum dorsiflexion of the 1 st metatarsal-hallux (1 st MT-Hal) (17.5° vs. 34.8°) during stance phase (ST), supination of the 1 st MT-Hal during swing phase (SW) (4° vs. 7°), maximum plantarflexion of the ankle during ST (-6.8° vs.-11.2°), and maximum varus of the ankle during SW (4.4° vs. 6.9°) were also lower for clubfoot except for maximum dorsiflexion of the navicular-1 st MT (P<0.05). CONCLUSION: This study supports evidence that surgically treated clubfoot continues to have residual deformity of forefoot, overcorrection of hindfoot, stiffness, and a decrease in physical functioning. This comprehensive study accurately portrays postsurgical clubfoot function with objective means through appropriate technologies. A plantar pressure redistributed and finite element analysis designed orthosis may be of importance in the improvement of the foot and ankle joint function for ambulatory children with a relapse of clubfoot deformity.

Serial CAD/CAM Bracing: An Alternative to Serial Casting for Early Onset Scoliosis.

BACKGROUND: Years of casting for infantile scoliosis can lead to significantly detrimental quality of life for both the child and parents. Concerns have been raised about the long-term negative neurodevelopmental effects of repeated anesthesia on young children. We developed an elongation bending derotation brace (EBDB) that uses primarily a bending derotation force applied to the curve to achieve the same goals as the cast. The goal of the study is to describe the preliminary results of a technique for creation of EBDB for infantile idiopathic scoliosis using computer-aided design/computer-aided milling (CAD/CAM) technology with at least 24 months follow-up. METHODS: Nine patients with infantile idiopathic scoliosis had minimum 2-year follow-up (mean, 3.4 y; range, 2 to 6 y). Mean age at the treatment was 11 months (4 to 24 mo). There were 2 right thoracic, 7 left thoracic curves. CAD/CAM technology was used to create the EBDB after the child was placed in traction and a derotation strap applied. The same rotational forces that are used in the creation of the Mehta-type cast can also be utilized in creating the brace. A laser scanner was used to obtain the spinal geometry. Compliance can be monitored with a heat sensor. RESULTS: Four patients were full corrected with serial bracing alone (curve ≤10 degrees). Five patients with more rigid curves showed improvement from mean 57 degrees (48 to 62 degrees) to mean 21 degrees (10 to 44 degrees). CONCLUSIONS: This paper describes the preliminary results of a new methodology for creating a patient-specific brace for infantile scoliosis using CAD/CAM technology. This methods shows promising potential to treat the infantile curve without the drawbacks of casting. LEVEL OF EVIDENCE: Level IV.

Effect of an elongation bending derotation brace on the infantile or juvenile scoliosis.

BACKGROUND: A wide variety of braces are commercially available designed for the adolescent idiopathic scoliosis (AIS), but very few braces for infantile scoliosis (IS) or juvenile scoliosis (JS). The goals of this study were: 1) to briefly introduce an elongation bending derotation brace (EBDB) in the treatment of IS or JS; 2) to investigate changes of Cobb angles in the AP view of X-ray between in and out of the EBDB at 0, 3, 6, 9, and 12 months; 3) to compare differences of Cobb angles (out of brace) in 3, 6, 9, and12 month with the baseline; 4) to investigate changes (out of brace) in JS and IS groups separately. METHODS: Thirty-eight patients with IS or JS were recruited retrospectively for this study. Spinal manipulation was performed using a stockinet. This was done simultaneously with a surface topography scan. The procedure was done in the operating room for IS, or in a clinical setting for JS. The brace was edited and fabricated using CAD/CAM method. Radiographs were recorded in and out of bracing approximately every 3 months from baseline to 12 months. A linear mixed effects model was used to compare in and out of bracing, and out of brace Cobb angle change over the 12 month period. RESULTS: Overall, 37.5% of curves are corrected and 37.5% stabilized after 12 months (Thoracic curves 48% correction, 19% stabilization; thoracolumbar curves 33% correction, 56% stabilization and lumbar curves 29% correction, 50% stabilization). The juvenile group had 25.7% correction and 42.9% stabilization, while the infantile group had 50% correction and 32.1% stabilization. There was a significant Cobb angle in-brace reduction in the thoracic (11°), thoracolumbar (12°), and lumbar (12°) (p < 0.001). There was no statistically significant change in out of brace Cobb angle from baseline to month 12 (p > 0.05). No patients required surgery within the 12 month span. CONCLUSIONS: This study describes a new clinical protocol in the development of the EBDB. Short-term results show brace is effective in preventing IS or JS curve progression over a 12 month span.

Reliability of Three-Dimensional Spinal Modeling of Patients With Idiopathic Scoliosis Using EOS System.

STUDY DESIGN: Three-dimensional (3D) spinal models of children with idiopathic scoliosis (IS) were created using the EOS imaging system (EOS) and sterEOS software. OBJECTIVE: To determine the inter- or intraobserver reproducibility of the 3D spinal models in children with IS of different apex locations. SUMMARY OF BACKGROUND DATA: 3D spinal model measurements include the Cobb angle, kyphosis, lordosis, and axial vertebral rotation (AVR). Variation of these measurements between two investigators and two different trials by the same investigator were analyzed by inter- and intraclass correlation coefficients (ICCs). METHODS: Biplanar radiographic images of 15 patients (age: 6-15 years) with IS were uploaded into the sterEOS software. Spinal and pelvic markers were manually identified to construct a 3D spinal model and measure spinal parameters. Two trained examiners independently performed modeling and performed modeling in spaced out trials. The ICC between inter- and intraobservers were calculated. RESULTS: ICCs between inter- and intraobservers were significant for all parameters (p < .05). Both the inter- and intraobservers showed excellent agreement for the Cobb angles in the thoracic segment, kyphosis and lordosis. Substantial interobserver agreement and excellent intraobserver agreement were determined for the Cobb angle in the thoracolumbar or lumbar (TL/L) segment, with less than 6° difference between two raters and less than 2° difference between two trials. Substantial interobserver agreement for the AVR in the TL/L region and substantial interobserver agreement for the AVR in the thoracic region were found, with less than 4° difference between raters. One rater had substantial intraobserver agreement for the AVR in the TL/L region whereas another rater reported moderate to substantial intraobserver agreement in both the thoracic and TL/L regions, with less than 3° difference between trials. CONCLUSION: The EOS system shows reliable and repeatable results in 3D spinal modeling of children with IS. LEVEL OF EVIDENCE: Level III.

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

BACKGROUND: Orthoses commonly are prescribed to children with cerebral palsy (CP) to provide foot correction and to improve ambulatory function. Immediate effects of ankle foot orthosis (AFOs) have been investigated, but long-term kinematic effects are lacking clinical evidence. OBJECTIVE: To determine changes in 3-dimensional ankle and foot segment motion in pediatric patients with CP between initial and follow-up visits (18-month average time differences) in both barefoot gait and gait with their AFO. We also investigated intravisit changes between barefoot and AFO gait. DESIGN: A prospective cohort study. SETTING: Children's Hospital of Wisconsin, Department of Orthopaedic Surgery, Medical College of Wisconsin. PATIENTS: A total of 23 children with CP, mean age 10.5 years (6.2-18.1 years) were clinically prescribed either a solid ankle foot orthotic (SAFO), hinged ankle foot orthotic (HAFO), or supramalleolar orthotic. METHODS: Holes were cut in the study orthoses so that electromagnetic markers could be directly placed on the skin. A 6-foot segment model was used. OUTCOME MEASUREMENTS: Kinematic and kinetic data were recorded for each patient's initial and follow-up visit (18-month follow-up average, 15-20 months range). RESULTS: For the SAFO group (gait with AFO), a significant decrease in dorsiflexion was found between the initial and third visit (P = .008). Furthermore, the SAFO group (barefoot gait) had an increased eversion at the midfoot for most of the gait cycle (P < .008). Sagittal forefoot range of motion was reduced for all 3 groups between the barefoot and AFO groups. CONCLUSION: The use of AFOs long term either maintained or improved foot deformities or dysfunction. LEVEL OF EVIDENCE: Level II.

Comparison of biomechanical behavior between a cast material torso jacket and a polyethylene based jacket.

BACKGROUND: Numerous designs are used to the treatment of Early Onset Scoliosis. For example, a Thoraco-Lumbo-Sacral Orthosis (TLSO) is constructed using Polyethylene (PE). In addition, a series of castings has been implemented using cast material (3M, BSN Medical). The cast material has some significant advantages over the PE design including: growth preserving, improved compliance, decreased invasiveness, delaying or avoiding surgery, and the ability to allow the skin to breathe. However, the mechanical effectiveness of the cast material brace as compared to the TLSO is unknown, thus providing the objective of this study. METHODS: A total of 23 standardized tensile tests were performed on the Delta-Cast Soft(®) and 3M(TM) Scotchcast(TM) Plus Casting Tape in order to obtain mechanical properties (Young's and shear moduli and Poisson ratios). Using a radiograph of a thoracic spine, the size of twelve vertebrae and eleven intervertebral discs were measured and used to create a finite element spine model. Simulations using this model were used to establish mechanical loads which were then applied to finite element models of the TLSO and cast jacket. The thicknesses and number of material layers was varied in these models. Multiple simulations were performed. RESULTS: It was found that a 6.6.mm thick cast jacket made of Delta-Cast Soft(®) had a maximum deformation of 4.7 mm, a maximum stress of 2.9 MPa and a structural factor of safety of 5.71. On the other hand, a 4 mm thick jacket made of PE had a maximum deformation of 2 mm, a maximum stress of 8.9 MPa and a structural factor of safety of 2.70. The cast jacket was 3.5 times lighter and had a material of cost 1/5 of the PE brace. CONCLUSIONS: Based on the results, either design will generate the proper constraint forces to maintain spinal correction. But, based on the design parameters (thickness, mechanical properties, structural factor of safety and cost) the brace made of cast material, though slightly thicker has superior structural and cost benefits. Thus, from the biomechanical point of view, the cast brace is more efficient than the PE brace.

Emergency department on-call status for pediatric orthopaedics: a survey of the POSNA membership.

BACKGROUND: The emergency room on-call status of pediatric orthopaedic surgeons is an important factor affecting their practices and lifestyles and was last evaluated in 2006. METHODS: The entire membership of the Pediatric Orthopaedic Society of North America (POSNA) was surveyed in 2010 for information regarding their emergency room on-call status with 382 surveys returned of over 1000 e-mailed to members of POSNA. Detailed information about on-call coverage, support, and frequency was obtained in answers to 14 different questions. RESULTS: Compared with the prior survey in 2006, the 2010 survey indicated that a higher percentage of pediatric orthopaedic surgeons receive compensation for taking emergency room call; a higher percentage cover pediatric patients only when on-call; and accessibility to operating rooms in a timely manner for trauma cases, although limited, has improved for pediatric patients. Utilization of support staff to meet on-call trauma coverage demands, such as residents, physician's assistants, and nurse practitioners, is becoming more common. CONCLUSIONS: Concentration of pediatric orthopaedic trauma has increased the coverage demands on pediatric orthopaedists. This has resulted in a change in reimbursement strategies, and allocation of OR time and hospital staffing resources.

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

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

Screening for adolescent idiopathic scoliosis: an information statement by the scoliosis research society international task force.

BACKGROUND: Routine screening of scoliosis is a controversial subject and screening efforts vary greatly around the world. METHODS: Consensus was sought among an international group of experts (seven spine surgeons and one clinical epidemiologist) using a modified Delphi approach. The consensus achieved was based on careful analysis of a recent critical review of the literature on scoliosis screening, performed using a conceptual framework of analysis focusing on five main dimensions: technical, clinical, program, cost and treatment effectiveness. FINDINGS: A consensus was obtained in all five dimensions of analysis, resulting in 10 statements and recommendations. In summary, there is scientific evidence to support the value of scoliosis screening with respect to technical efficacy, clinical, program and treatment effectiveness, but there insufficient evidence to make a statement with respect to cost effectiveness. Scoliosis screening should be aimed at identifying suspected cases of scoliosis that will be referred for diagnostic evaluation and confirmed, or ruled out, with a clinically significant scoliosis. The scoliometer is currently the best tool available for scoliosis screening and there is moderate evidence to recommend referral with values between 5 degrees and 7 degrees. There is moderate evidence that scoliosis screening allows for detection and referral of patients at an earlier stage of the clinical course, and there is low evidence suggesting that scoliosis patients detected by screening are less likely to need surgery than those who did not have screening. There is strong evidence to support treatment by bracing. INTERPRETATION: This information statement by an expert panel supports scoliosis screening in 4 of the 5 domains studied, using a framework of analysis which includes all of the World Health Organisation criteria for a valid screening procedure.

Development of a 3-Dimensional Back Contour Imaging System for Monitoring Scoliosis Progression in Children.

STUDY DESIGN: Control study. OBJECTIVES: To present a new surface topography system capable of taking 3-dimensional (3D) spine measurements, to establish baseline values for the measured parameters in a typically developing population, and to determine the intra-rater and inter-rater reproducibility of these parameters. SUMMARY OF BACKGROUND DATA: Cumulative exposure to radiation from diagnostic radiographs increases patient risk for cancer development. There is a need for noninvasive and non-radiographic tools to accurately and reproducibly measure spine deformity and track scoliosis progression. METHODS: We measured 10 typically developing subjects with the new Milwaukee Topography System, which is composed of 2 electromagnetic markers, an electronic processing unit, a handheld laser scanner, a software package, and a desktop computer. Two investigators separately scanned the same subjects multiple times, yielding a total of 4 scans per subject per investigator. We measured 17 3D back parameters in each scan. We performed a multivariate analysis of variances to test the hypothesis of no difference for all variables, measured intra-rater and inter-investigator reliability with intra-class correlation (ICC) coefficients, and calculated mean values. RESULTS: There were highly reproducible ICC values between investigators for 6 parameters (ICC > 0.75), moderate ICC values for 8 parameters (0.75 > ICC > 0.4), and poor ICC values for 3 parameters (ICC < 0.4), all at p < .05. Intra-investigator ICCs were moderate to excellent for almost all parameters. CONCLUSIONS: The Milwaukee Topography System can be used to monitor and measure 3D back contours in children. The 3D back parameters values measured in the typically developing population can be considered baseline values that can be compared with parameters measured in children with idiopathic scoliosis.

Reproducibility of newly developed spinal topography measurements for scoliosis.

OBJECTIVE: In an effort to limit exposure to ionizing radiation and fully characterize three dimensional changes in the spine of patients with scoliosis reliable non-invasive methods of spinal back contour analysis (Milwaukee Topographic Scanner) (MTS) have been developed. STUDY DESIGN: The current study compares spinal topography measurements among different subject positions and evaluates the reproducibility of the system for both inter-rater and intra-rater reliability. METHODS: A dummy cast (plastic cast) of one patient with adolescent idiopathic scoliosis was created in order to test the reliability of the MTS. The dummy cast was positioned and rotated in 3D while scanned by two investigators using the MTS. A total of twelve parameters including Q-angle (an analog to X-ray's Cobb angle) were extracted. RESULTS: All measurements of intra-rater and inter-rater reliability were excellent (Intraclass Correlation Coefficients ranging from 0.89 to 0.99) with the exception of Pelvic Tilt (intra-rater ICC is 0.61) and lordosis angle (inter-rater ICC is 0.82). No significant variability among investigators was observed for all tested metrics. No significant variability due to position was observed for the majority of back contour measurements but there were significant changes in the T1-S1 angle, T1-S1 deviation, T1-NC angle, T1-NC deviation, and Back Height metric (p< 0.05). CONCLUSIONS: The MTS is a reliable method of raster stereography in the measurement of the back contour, which will help monitor the progression of children with idiopathic scoliosis and reduce the use of X-rays.

The in-vivo effect of torque on growth in caudal vertebrae.

Numerous studies involving axial distraction and compression of the spine indicate that longitudinal loading affects the vertebral growth plate as well as modulation of spinal growth. Furthermore, asymmetric loading is involved in curve progression as a result of vertebral bone changes and disc wedging. As with longitudinal loading, direct or indirect application of torque to the growth plate may have an influence as well. A study was undertaken to develop a fixture that may be applied in-vivo to generate controlled torsional loads and to examine the effect of such torsional loads on the growth plate in caudal vertebrae. It is shown that application of torque leads to curvature in the morphology of the growth plate, a reduced width (medial to lateral distance of the growth plate) and remarkably increased thickness (height of 3 physeal zones in the growth plate) and dramatically widened disc space.

Insole-pressure distribution for normal children in different age groups.

BACKGROUND: In measuring plantar pressures during gait, earlier methods have used a platform system that does not take into account the interactions feet have with orthotics and shoe wearing. The purpose of the study was to provide normal insole plantar pressure parameter data during stance phase using the Pedar pressure insole system. METHODS: Twenty-nine normal children, age 6 to 16 years, were recruited and walked along the 25 m walkway at self-selected speeds. Patients were divided into 2 separate groups for statistical analysis--juniors (< 12 y old) and teenagers (> 13 y old). The pressure map was divided into 8 regions (masks) determined by anatomic landmarks and a total of 7 pressure parameters were analyzed of each mask. RESULTS: We did not detect significant differences in foot pressures between juniors and teenagers when regarding sex, or left and right feet for 7 parameters measured. CONCLUSIONS: This normative data will provide a basis with which to more accurately assess pediatric pathologic foot deformities and to distinguish dynamic foot deformities from anatomic foot deformities. THE LEVEL OF EVIDENCE: Level II.

Electromyography nerve conduction velocity evaluation of children with clubfeet.

Neurologic deficit has been implicated as a possible etiology for clubfoot and a cause for recurrent deformity in patients who have undergone clubfoot surgery. In the study reported here, we wanted to determine if clubfoot patients with peroneal weakness had any neurologic deficits on electromyography nerve conduction velocity (EMG-NCV) studies before surgery and if there was any association between neurologic deficit and clubfoot recurrence. We reviewed the EMG-NCV studies of 36 patients involving 57 cases of idiopathic clubfoot and recurrence of the deformity or muscle weakness. In the clubfoot patients with weak peroneal muscle and no prior surgical history, 45% of the studies were interpreted as normal, 20% as neuropathic, 15% as mixed myopathic and neuropathic, 10% as radicular, and 10% as myopathic. In the clubfoot patients with recurrence after clubfoot repair surgeries, 57% had abnormal EMG-NCV studies. Specifically, peroneal mononeuropathy was the most common disorder (41% of clubfoot patients treated surgically). Awareness of a significant incidence of neurologic deficit may help in preoperative planning by indicating that ultimately a tendon transfer may be necessary to obtain a plantigrade foot.

MRI pathoanatomy study of congenital vertical talus.

BACKGROUND: Prior reports regarding the pathologic anatomy for congenital vertical talus have noted some disagreement as to which elements of the pathologic anatomy are consistently present. The purpose of his study is to evaluate the 3-dimensional morphologic changes and pathoanatomy of the congenital vertical talus using magnetic resonance imaging. METHODS: Nine patients with congenital vertical talus (ranging from 5 mo-11 y) underwent magnetic resonance imaging of both feet. A foot and ankle coil was used for the 1.5 T system. The protocol consisted of T1-weighted spin echo sequence image and T2-weighted fast spin echo sequence image in the sagittal, coronal, and axial planes. Slice thickness ranged from 3 to 4 mm with 0 to 1.0 mm interspace thickness. A descriptive analysis was performed based upon the T1-weighted image by physicians. RESULTS: At the level of the talonavicular joint, the navicular was seen significantly subluxed dorsally with associated wedging of the navicular. At the level of the calcaneocuboid joint, often there was a significant dorsal subluxation of the cuboid in relation to the calcaneus. Lateral obliquity of the calcaneocuboid joint could be present to varying degrees. The anterior calcaneus was significantly laterally displaced in relation to the talar head with an element of lateral translation and eversion of the calcaneus at the subtalar joint. Distal cavus at the cuneiform-first metatarsal joint was observed in 5 patients. CONCLUSIONS: This study suggests that there is significant pathology at the level of subtalar joint in congenital vertical talus. In addition to satisfactory reduction of the talonavicular joint, methods to ensure realignment of the calcaneus under the talus may be a crucial component of deformity correction and to prevent recurrence of deformity. LEVEL OF EVIDENCE: A Level III diagnostic study using normal pediatric foot anatomy in magnetic resonance imaging as a reference.