Nancy Lennon

Variability of energy-consumption measures in children with cerebral palsy

Oxygen consumption measurements made on five repeated tests from five children with cerebral palsy (CP) and five nondisabled children of similar age and size were collected using the Cosmed K2 (Cosmed, Rome, Italy) oxygen-analysis system at free-walking velocity. Oxygen cost, oxygen consumption, and physiological cost index (PCI) were measured. There were no statistically significant differences in the percentage of variability of oxygen cost, oxygen consumption, or PCI between the disabled and nondisabled populations. Oxygen cost was the most reliable oxygen-use measurement with an average percentage of variability of 13.2% for the CP population and 13.9% for the nondisabled population. Physiological cost index was found be the least reliable measurement with the average percentages of variabilities of the disabled and nondisabled populations of 20.3 and 20.5%, respectively. Thus because of oxygen costs relatively low variability, it was the most sensitive measurement of change in gait efficiency.

Distal hamstring lengthening in ambulatory children with cerebral palsy: primary versus revision procedures.

To document the benefits and limitations of distal hamstring lengthening (HL), 61 children (105 limbs) with cerebral palsy treated by distal HL with complete preoperative and postoperative evaluations were reviewed. There was significant improvement in popliteal angle, fixed knee flexion contracture, knee angle at foot contact (FC), and mid-stance knee extension after HL. On the other hand, the hip power generation peak decreased, and the anterior pelvic tilt increased. For the repeated HL (22 limbs), the fixed knee flexion contracture and knee flexion at FC improved. In a group of ten patients (17 limbs) with further postoperative follow up evaluations, the only significant clinical finding related to hamstring function between the first postoperative and the follow up evaluations with no intervening surgery was an increase in the popliteal angle of 20 degrees. Because the popliteal angle may increase over time after HL with no other directly related gait changes, the indications for repeated HL should include fixed knee flexion contracture and increased knee flexion at FC. The increase in the popliteal angle alone should not be considered an indication for repeated HL.

A comprehensive outcome comparison of surgical and Ponseti clubfoot treatments with reference to pediatric norms

PurposeIsolated congenital clubfoot can be treated either operatively (posteromedial release) or conservatively (Ponseti method). This study retrospectively compared mid-term outcomes after surgical and Ponseti treatments to a normal sample and used multiple evaluation techniques, such as detailed gait analysis and foot kinematics.MethodsTwenty-six children with clubfoot treated surgically and 22 children with clubfoot treated with the Ponseti technique were evaluated retrospectively and compared to 34 children with normal feet. Comprehensive evaluation included a full gait analysis with multi-segment and single-segment foot kinematics, pedobarograph, physical examination, validated outcome questionnaires, and radiographic measurements.ResultsThe Ponseti group had significantly better plantarflexion and dorsiflexion range of motion during gait and had greater push-off power. Residual varus was present in both treatment groups, but more so in the operative group. Gait analysis also showed that the operative group had residual in-toeing, which appeared well corrected in the Ponseti group. Pedobarograph results showed that the operative group had significantly increased varus and significantly decreased medial foot pressure. The physical examination demonstrated significantly greater stiffness in the operative group in dorsiflexion, plantarflexion, ankle inversion, and midfoot abduction and adduction. Surveys showed that the Ponseti group had significantly more normal pediatric outcome data collection instrument results, disease-specific indices, and Dimeglio scores. The radiographic results suggested greater equinus and cavus and increased foot internal rotation profile in the operative group compared with the Ponseti group.ConclusionsPonseti treatment provides superior outcome to posteromedial release surgery, but residual deformity still persists.

Systematic review of the clinimetric properties of laboratory- and field-based aerobic and anaerobic fitness measures in children with cerebral palsy

OBJECTIVE To systematically evaluate the level of evidence of the clinimetric properties of measures of aerobic and anaerobic capacity used for children with cerebral palsy (CP). DATA SOURCES A systematic search of databases PubMed, Embase, SPORTDiscus, and PsycINFO through April 2011 was performed. STUDY SELECTION Two independent raters identified and examined studies that reported laboratory- or field-based measures of maximal aerobic or anaerobic capacity in children with CP aged 5 to 14 years. DATA EXTRACTION The COnsensus-based Standards for the selection of health status Measurement INstruments (COSMIN) checklist was used by 2 independent raters to evaluate the methodologic quality of the included clinimetric studies and to identify measures used in these studies. DATA SYNTHESIS Twenty-four studies that used a maximal aerobic or anaerobic capacity measure were identified. Five studies reported clinimetric properties for 5 measures (2 aerobic and 3 anaerobic measures). Methodologic quality was excellent in 3 studies, showing good validity and reliability of field-based aerobic (Shuttle Run Test) and anaerobic (Muscle Power Sprint Test) measures. The studies on laboratory-based measures were rated fair, mainly because of inadequate statistics. The level of evidence was strong for good validity and reliability of the field-based tests. The level of evidence was unknown for validity and low to moderate for good reliability of laboratory-based tests. CONCLUSIONS There is a paucity of research on the clinimetric properties of measurement instruments to assess aerobic and anaerobic capacity for children with CP. Further clinimetric studies of laboratory-based measures in children with CP at all Gross Motor Function Classification System (GMFCS) levels, and clinimetric studies of field-based measures in children who are classified as GMFCS levels III to V are required.

Reliability and Validity of Objective Measures of Physical Activity in Youth With Cerebral Palsy Who Are Ambulatory

Background Physical therapy for youth with cerebral palsy (CP) who are ambulatory includes interventions to increase functional mobility and participation in physical activity (PA). Thus, reliable and valid measures are needed to document PA in youth with CP. Objective The purpose of this study was to evaluate the inter-instrument reliability and concurrent validity of 3 accelerometer-based motion sensors with indirect calorimetry as the criterion for measuring PA intensity in youth with CP. Methods Fifty-seven youth with CP (mean age=12.5 years, SD=3.3; 51% female; 49.1% with spastic hemiplegia) participated. Inclusion criteria were: aged 6 to 20 years, ambulatory, Gross Motor Function Classification System (GMFCS) levels I through III, able to follow directions, and able to complete the full PA protocol. Protocol activities included standardized activity trials with increasing PA intensity (resting, writing, household chores, active video games, and walking at 3 self-selected speeds), as measured by weight-relative oxygen uptake (in mL/kg/min). During each trial, participants wore bilateral accelerometers on the upper arms, waist/hip, and ankle and a portable indirect calorimeter. Intraclass coefficient correlations (ICCs) were calculated to evaluate inter-instrument reliability (left-to-right accelerometer placement). Spearman correlations were used to examine concurrent validity between accelerometer output (activity and step counts) and indirect calorimetry. Friedman analyses of variance with post hoc pair-wise analyses were conducted to examine the validity of accelerometers to discriminate PA intensity across activity trials. Results All accelerometers exhibited excellent inter-instrument reliability (ICC=.94–.99) and good concurrent validity (rho=.70–.85). All accelerometers discriminated PA intensity across most activity trials. Limitations This PA protocol consisted of controlled activity trials. Conclusions Accelerometers provide valid and reliable measures of PA intensity among youth with CP.

Persistence and Recurrence Following Femoral Derotational Osteotomy in Ambulatory Children With Cerebral Palsy

Background: Excessive hip internal rotation is frequently seen in children with cerebral palsy (CP). Femoral derotational osteotomy (FDO) is effective in the short term, but factors associated with long-term correction remain unclear. The purposes of this study were to define the incidence of persistence and recurrence of hip internal rotation following FDO in ambulatory children with CP and to evaluate factors that influence outcome. Methods: Following IRB approval, kinematic and passive range of motion (PROM) variables were retrospectively evaluated in children with spastic CP who had FDO to correct hip internal rotation as part of clinical care at a children’s specialty hospital. Children included had a preoperative evaluation (Vpre), a short-term postoperative evaluation (Vshort, 1 to 3 y post), and, in some cases, a long-term postoperative evaluation (Vlong, ≥5 y post). Age at surgery, physical exam measures, and kinematics variables were evaluated as predictors for dynamic and static recurrence. Results: Kinematic hip rotation improved from 14±12 degrees (Vpre; internal positive) to 4±13 degrees (Vshort) and relapsed to 9±15 degrees long term (P<0.05 Vpre/Vshort/Vlong; 99 limbs). Hip PROM midpoint improved from 23±9 degrees (Vpre) to 8±11 degrees (Vshort) and relapsed to 14±13 degrees (P<0.01 Vpre/Vshort/Vlong). Persistent hip internal rotation was noted in 41% (kinematics) and 18% (PROM) of limbs at Vshort (105 children, 178 limbs). Of limbs that showed initial improvement at Vshort (62 children, 95 limbs), recurrence was seen in 40% (kinematic hip rotation) and 39% (hip midpoint) at Vlong. Comparing children who had recurrent hip internal rotation and those who maintained long-term correction, we saw higher levels of spasticity and lower gait velocity in the recurrent group (P<0.05). Conclusions: Although FDO is an accepted treatment in children with CP, persistence and recurrence of hip internal rotation can occur. Recurrence is associated with spasticity and slower gait velocity. Predictor variables may be useful for surgeons during preoperative discussions of expected outcome with families of FDO candidates. Level of Evidence: Level III.

Reliability and validity of Edinburgh visual gait score as an evaluation tool for children with cerebral palsy

Assessment of gait abnormalities in cerebral palsy (CP) is challenging, and access to instrumented gait analysis is not always feasible. Therefore, many observational gait analysis scales have been devised. This study aimed to evaluate the interobserver reliability, intraobserver reliability, and validity of Edinburgh visual gait score (EVGS). Video of 30 children with spastic CP were reviewed by 7 raters (10 children each in GMFCS levels I, II, and III, age 6-12 years). Three observers had high level of experience in gait analysis (10+ years), two had medium level (2-5 years) and two had no previous experience (orthopedic fellows). Interobserver reliability was evaluated using percentage of complete agreement and kappa values. Criterion validity was evaluated by comparing EVGS scores with 3DGA data taken from the same video visit. Interobserver agreement was 60-90% and Kappa values were 0.18-0.85 for the 17 items in EVGS. Reliability was higher for distal segments (foot/ankle/knee 63-90%; trunk/pelvis/hip 60-76%), with greater experience (high 66-91%, medium 62-90%, no-experience 41-87%), with more EVGS practice (1st 10 videos 52-88%, last 10 videos 64-97%) and when used with higher functioning children (GMFCS I 65-96%, II 58-90%, III 35-65%). Intraobserver agreement was 64-92%. Agreement between EVGS and 3DGA was 52-73%. We believe that having EVGS as part of the standardized gait evaluation is helpful in optimizing the visual scoring. EVGS can be a supportive tool that adds quantitative data instead of only qualitative assessment to a video only gait evaluation.

The effectiveness of posterior knee capsulotomies and knee extension osteotomies in crouched gait in children with cerebral palsy.

Crouched gait is common in children with cerebral palsy (CP), and there are various treatment options. This study evaluated the effectiveness of single-event multilevel surgery including posterior knee capsulotomy or distal femoral extension osteotomy to correct knee flexion contracture in children with CP. Gait analyses were carried out to evaluate gait preoperatively and postoperatively. Significant improvements were found in physical examination and kinematic measures, which showed that children with CP and crouched gait who develop knee flexion contractures can be treated effectively using single-event multilevel surgery including a posterior knee capsulotomy or distal femoral extension osteotomy.

Validity of the OMNI rating of perceived exertion scale for children and adolescents with cerebral palsy

This study evaluated the validity of the OMNI Walk/Run Rating of Perceived Exertion (OMNI‐RPE) scores with heart rate and oxygen consumption (VO2) for children and adolescents with cerebral palsy (CP).

Pre-operative walking activity in youth with cerebral palsy

BACKGROUND No data are available regarding level of walking activity for youth with cerebral palsy (CP) before undergoing orthopeadic surgery. The goals of this study were to quantify pre-operative walking activity, and determine whether pre-operative values are different from previously defined levels of walking activity in youth with CP. PROCEDURES This study retrospectively evaluated pre-operative walking activity in youth with spastic CP, GMFCS levels I-IV. Walking activity was monitored using the StepWatch™. Outcome variables included mean daily strides, percent of day active, and percent of active time at high activity. Differences between GMFCS levels were examined and comparisons were made to published data. RESULTS Pre-operative walking activity data from 126 youth with CP were included. All variables demonstrated higher walking activity in youth at GMFCS levels I/II compared to those at GMFCS levels III/IV. When compared to previously defined walking activity levels, pre-operative walking activity was lower. CONCLUSIONS Walking activity among pre-operative youth with CP is significantly lower than published data for ambulatory youth with CP. Results suggest that youth with CP who are surgical candidates have less walking activity than youth with CP without surgical needs. Therefore this study should encourage the effort to collect and analyze individual pre-operative data for comparison and evaluation of post-operative functional recovery.