The Effects of Varying Ankle Foot Orthosis Stiffness on Gait in Children with Spastic Cerebral Palsy Who Walk with Excessive Knee Flexion (original) (raw)
Related papers
Journal of Applied Biomechanics, 2014
A rigid ventral shelf ankle foot orthosis (AFO) may improve gait in children with spastic cerebral palsy (SCP) whose gait is characterized by excessive knee flexion in stance. However, these AFOs can also impede ankle range of motion (ROM) and thereby inhibit push-off power. A more spring-like AFO can enhance push-off and may potentially reduce walking energy cost. The recent development of an adjustable spring-hinged AFO now allows adjustment of AFO stiffness, enabling tuning toward optimal gait performance. This study aims to quantify the mechanical properties of this spring-hinged AFO for each of its springs and settings. Using an AFO stiffness tester, two AFO hinges and their accompanying springs were measured. The springs showed a stiffness range of 0.01-1.82 N·m·deg -1 . The moment-threshold increased with increasing stiffness (1.13-12.1 N·m), while ROM decreased (4.91-16.5°). Energy was returned by all springs (11.5-116.3 J). These results suggest that the two stiffest available springs should improve joint kinematics and enhance push-off in children with SCP walking with excessive knee flexion.
BMC Pediatrics, 2013
Background: Ankle-Foot-Orthoses with a ventral shell, also known as Floor Reaction Orthoses (FROs), are often used to reduce gait-related problems in children with spastic cerebral palsy (SCP), walking with excessive knee flexion. However, current evidence for the effectiveness (e.g. in terms of walking energy cost) of FROs is both limited and inconclusive. Much of this ambiguity may be due to a mismatch between the FRO ankle stiffness and the patient's gait deviations. The primary aim of this study is to evaluate the effect of FROs optimised for ankle stiffness on the walking energy cost in children with SCP, compared to walking with shoes alone. In addition, effects on various secondary outcome measures will be evaluated in order to identify possible working mechanisms and potential predictors of FRO treatment success.
Effect of ankle-foot orthoses on walking efficiency and gait in children with cerebral palsy
Journal of Rehabilitation Medicine, 2008
To determine the effect of ankle-foot orthoses on walking efficiency and gait in a heterogeneous group of children with cerebral palsy, using barefoot walking as the control condition. Design: A retrospective study. Methods: Barefoot and ankle-foot orthosis data for 172 children with spastic cerebral palsy (mean age 9 years; hemiplegia: 21, diplegia: 97, and quadriplegia: 54) were compared. These data consisted of non-dimensional speed, net nondimensional energy cost of walking (NN-cost), and NN-cost as a percentage of speed-matched controls (NN-cost pct ). For 80 of these children the Gillette Gait Index and data for 3D gait kinematics and kinetics were also analyzed. Results: Speed was 9% faster (p < 0.001), NN-cost was 6% lower (p = 0.007), and NN-cost pct was 9% lower (p = 0.022) when walking with an ankle-foot orthosis. The Gillette Gait Index remained unchanged (p = 0.607). Secondary subgroup analysis for involvement pattern showed a significant improvement in NN-cost pct only for quadriplegics (20%, p = 0.004), whereas it remained unchanged for patients with hemiplegia and diplegia. Changes in the minimum knee flexion angle in stance phase and in terminal swing were found to be significantly related to the change in NN-cost pct (p = 0.013 and p = 0.022, respectively). Conclusion: The use of an ankle-foot orthosis resulted in a significant decrease in the energy cost of walking of quadriplegic children with cerebral palsy, compared with barefoot walking, whereas it remained unchanged in hemiplegic and diplegic children with cerebral palsy. Energy cost reduction was related to both a faster and more efficient walking pattern. The improvements in efficiency were reflected in changes of stance and swing phase knee motion, i.e. those children whose knee flexion angle improved toward the typical normal range demonstrated a decrease in energy cost of walking, and vice versa.
2010
The current study aimed to investigate influences of rigid Ankle Foot Orthoses (AFOs) on gait in children with Cerebral Palsy (CP), immediate effects of tuning of AFO-FC (AFO-Footwear Combination) on gait of children with CP, short-term effects of tuning of AFO-FC on gait, muscle and joint characteristics and quality of life in children with CP, and the feasibility of conducting a larger trial. The study included 11 healthy children and 8 children with CP. Outcome measurements included sagittal plane kinematics and kinetics derived using 3D motion analysis, Gait Deviation Index (GDI), physical examination, and quality of life using the PedsQL™ questionnaire. Data from healthy children demonstrated influences of shoes on gait parameters and the role of the ankle joint in adapting to various wedges and rockers during gait. When studying children with CP, beneficial effects of rigid AFO-FC on gait parameters were evident; these were thought to relate to the appropriateness of the AFO-FC and familiarisation with the prescription. Immediate effects of tuning varied according to gait patterns previously demonstrated with non-tuned AFO-FC; benefits to knee kinematics and kinetics were largely seen in legs with extended knee gait, followed by jump knee gait, and with poorest responses in legs with crouch knee gait. Short-term effects of tuning were evident when comparing measurements taken before and after two-to-four months of wearing the tuned AFO-FC. Barefoot walking demonstrated significantly improved walking speed. Stride-length improved when comparing tuned AFO-FC at baseline with the tuned AFO-FC following the intervention period. No short-term changes were seen in PedsQL™ scores, muscle and joint characteristics, and GDI. Feasibility issues were also identified. Dr Marietta van der Linden: Thank you for your continuous support and mentoring. I really appreciate you giving me the time and space, and additional support, to get me up to speed during the initial stages of the PhD. I am also very thankful to you for your dedication and many hours of hard work that you have put into reading my thesis. Dr. Fiona Coutts: Thank you for continuous support as a line manager, supervisor and friend. I really appreciate you looking out for me all through my PhD, and supporting and guiding me at crucial moments of my career and life. I am very grateful for all your valuable feedback and advice. Dr Tom Mercer: Thank you for your valuable comments and support. I appreciate the way you have challenged my thinking and helped me streamline the thesis at crucial times. Jan Herman and Jacky Yirrel: Thank you for collaborating in this research through your valuable input in the original ideas, through individual data collection sessions and ongoing discussions that have been highly influencial in the project. Anderson's Gait Laboratory and Dr Alison Richardson: Thank you for allowing me to use the laboratory when it was needed the most, and collaborating with me on the project through assistance in participant recruitment and data collection sessions. Callum Ferguson, Lyndsay Forbes and Peacock's Medical group, Edinburgh: Thank you for collaboration in this research and your valuable input. I have appreciated your support through providing expertise and facilities for the design and production of orthotics and tuning materials. Robert Rush, Barry Meadows and Elaine Owen: Thank you for your valuable input and expert advice in the design and organisation of the study. Mr. James Robb: Thank you for the critical comments and questions which have challenged my thinking and helped to improve my thesis. Richard Wilson and Andrew Grainger: Thank you for all the technical support and advice. All my participants: My earnest thanks to all the children and their parents who participated in this study, for their patience, support and trust. I also thank all the adult participants in my study.
This study compared the effects of solid and hinged ankle-foot orthoses (AFOs) on the gait of children with spastic diplegic cerebral palsy (CP) who ambulate with excessive ankle plantar flexion during stance. Twelve children with spastic diplegic CP wore no AFOs for an initial 2-week period, solid AFOs for 1 month, no AFOs for 2 weeks, and hinged AFOs for 1 month. Lower extremity muscle timing, knee and ankle joint motions, moments and powers, and temporal-distance characteristics were measured during ambulation for an initial barefoot baseline test, and with solid and hinged AFOs for the other two tests. Both orthoses increased stride length, reduced abnormal ankle plantar flexion during initial contact, midstance and terminal stance (TST), and increased ankle plantar flexor moments closer to normal during TST. Hinged AFOs increased ankle dorsiflexion at TST and increased ankle power generation during preswing (PSW) as compared to solid AFOs, and increased ankle dorsiflexion at loading compared to no AFOs. No other significant differences were found for the gait variables when comparing these orthoses. Either AFO could be used to reduce the excessive ankle plantar flexion without affecting the knee position during stance. The hinged AFO would be recommended to produce more normal dorsiflexion during TST and increased ankle power generation during PSW in children with spastic diplegic CP.
Gait assessment of fixed ankle-foot orthoses in children with spastic diplegia
Archives of Physical Medicine and Rehabilitation, 1998
To evaluate the effectiveness of ankle-foot orthoses (AFOs) in spastic diplegic cerebral palsy patients for whom orthoses were indicated to control equinus or pes planovalgus deformities. A retrospective, cross-sectional assessment was performed on diplegic subjects who had suitable barefoot and AFO gait trials on the same day. Thirty-five subjects with a mean age of 8.7 yrs were included. Eighteen wore braces to control equinus and 17 to control pes planovalgus and crouch. Gait data assessed in all subjects included temporal-distance factors and sagittal kinematics. Force plate data to determine joint moments and powers were obtained in 20. Repeated measures analysis of variance was used to compare across conditions and indications. The cohort demonstrated increased velocity (10 cm/sec; p < .001), stride length (10 cm; p < .001), and percent single-limb support (1.8%; p < .002) using AFOs compared with barefoot gait. In braces, ankle excursion was reduced (p < .0001), while pelvic, hip, and knee excursions were increased to account for the temporal changes (p < .009). Effects were similar in both indication groups. In neither indication group did the AFO significantly alter knee position in stance. Kinetic analysis showed a reduction of abnormal power burst (p < .05) in early stance and an increase in late stance ankle moment (p < .05) with AFOs. Differences in gait characteristics and bracing effects are shown for both indication groups. Compared with barefoot gait, AFOs enhanced gait function in diplegic subjects. Benefits resulted from elimination of premature plantar flexion and improved progression of foot contact during stance. Effects on proximal joint alignment were not significant.
International Journal Of Community Medicine And Public Health, 2022
Background: In cerebral palsy, importance must be given on effective and efficient walking. 30 subjects; 16 males and 14 females (mean age 6.5 year) of spastic cerebral palsy with knee hyperextension and ankle equines were included in this study and were fitted with bilateral moldedhinged SKAFO with pair of shoes.Methods: Observational gait analysis by video recording was performed and gait parameters by 10 m walk test and knee angle at mid stance using goniometer in standing position were recorded in bracing and non-bracing conditions.Results: The orthosis controlled knee hyperextension by not restricting normal flexion and extension moment with smooth transition of ankle motion. There was significant improvement in step length; stride length as well as knee angle at midstance (with orthosis) but velocity and cadence were reduced as compared to bare foot walking.Conclusions: A stable, natural and controlled knee hyperextension gait pattern was found.
Journal of Electromyography and Kinesiology, 2014
Purpose: To determine the effects of decreased ankle-foot dorsiflexion (A-Fdf) range of motion (ROM) on gait kinematics in children with spastic cerebral palsy (SCP). Methods: All participants were children with spastic cerebral palsy (n = 10) who walked with knee flexion in midstance. Data were collected over 2-5 sessions, at 3-monthly intervals. A-Fdf ROM was quantified using a custom-designed hand-held ankle dynamometer that exerted 4 Nm at the ankle. Ankle-foot and knee angles during gait were quantified on sagittal video recordings. Linear regression (cross-sectional analysis) and General Estimation Equation analysis (longitudinal analysis) were performed to assess relationships between (change in) A-Fdf ROM and (change in) ankle-foot and knee angle during gait. Results: Cross-sectional analysis showed a positive relationship between A-Fdf ROM and both ankle-foot angle in midstance and terminal swing. Longitudinal analysis showed a positive relationship between individual decreases in A-Fdf ROM and increases of knee flexion during gait (lowest knee angle in terminal stance and angle in terminal swing). Conclusion: For this subgroup of SCP children, our results indicate that while changes in ankle angles during gait are unrelated to changes in A-Fdf ROM, changes in knee angles are related to changes in A-Fdf ROM.
Journal of Children's Orthopaedics, 2007
Purpose To evaluate the efficacy of ankle foot orthoses (AFOs) prescribed in the community for children with cerebral palsy (CP). Methods Fifty-six children (32 boys and 24 girls, mean age 8.9 years, range 4–17) who were diagnosed as having CP were enrolled. They were grouped according to the type of CP, diplegic ( n = 38) and hemiplegic ( n = 18). Three-dimensional gait analyses while patient were barefoot and with AFOs were obtained and analyzed. Results The spatio-temporal findings were the most significantly changed as a result of AFO use. In the hemiplegic group, stride length was 11.7% ( p = 0.001) longer with AFOs in both affected (10.2%) and non-affected (12.4%) legs, and cadence was reduced by 9.7%; walking speed was not affected. In the diplegic group, stride length with AFOs was 17.4% longer compared to barefoot ( p < 0.001) and walking velocity improved by 17.8% ( p < 0.001); cadence was unchanged. AFOs also increased ankle dorsiflexion at initial contact in both g...
Indian Journal of Physical Medicine and Rehabilitation
Objective: The aim of the study was to find the effect of ankle foot orthosis (AFO) on energy expenditure (EE) during walking in children with spastic diplegia (SD) due to cerebral palsy (CP). Materials and methods: Twenty-six subjects with SD CP who could ambulate with and without the help of orthosis were selected after screening with inclusion criteria. The EE of these patients during ambulation with and without orthoses was measured using the K4b 2 machine. Statistical analysis was performed with the help of Epi Info™ 3.5.3. t-test, chi-square test, and correlation tests were used to study the parameters of oxygen cost, oxygen pulse, heart rate, and EE. Results: The use of AFO resulted in decreased EE in 73% of patients in the first day itself. In the sequential assessment, these patients showed further decrease in EE with AFO use. The patients who initially showed an increase of EE also showed a decrease in the rise in EE during walking in their subsequent analysis. Oxygen cost also showed a positive correlation with EE. Heart rate was not much related to use of AFO; rather, it showed an increase in the assessment done second in the same day (among walking with and without the AFO). There was no linear relation or correlation between O 2 pulse and other parameters of the study. Conclusion: The AFOs are an important intervention in the treatment of SDs. It can help decrease the EE and improve the speed of walking in most patients when prescribed along with other needful therapies like exercises, antispastic medications, etc. O 2 cost showed positive correlation with EE analysis. In patients with increased EE with AFO use, the mean difference between EE with and without AFO decreases, suggesting long-term benefits that AFO could offer. A study of longer duration with more patients should be conducted to view the full benefits of AFO in children with SD CP.