Biomechanical Effects of a Powered Knee Orthosis and Articulated Ankle-Foot Orthoses in People with Cerebral Palsy
Bibliographic record
Abstract
Cerebral palsy affects 0.2% of live births, causing permanent effects on body movement and muscle coor-dination. Spasticity is a common occurrence in individuals with cerebral palsy. Spasticity refers to muscle tightness that varies with the speed of active and passive movement. Short-term clinical trials using robotic rehabilitation devices have shown gait improvements after training sessions comparable to invasive multi-level surgery for spastic cerebral palsy. These devices work to improve the musculoskeletal strength and mobility of individuals with cerebral palsy, which may then impact their community engagement and ability to socialize while minimizing day-to-day obstacles. Further research regarding the biomechanics of joints and robotic walkers for populations with pathological gaits is required to broaden the understanding of gait-related rehabilitation when paired with typically prescribed orthoses. This thesis aims to determine if articulated ankle-foot orthoses (AFOs) can complement the effectiveness of an actuated knee-ankle-foot orthosis with a powered knee (Agilik, Bionic Power Inc.®, Vancouver, BC, Canada) through two objectives. Firstly, we aim to specify the mechanical metrics of procured articulated AFOs to enable quantitative comparison between various articulated configurations against the normative rigid AFO prescription seen for populations with spasticity. Secondly, we aim to evaluate the effects of varying ankle stiffness and range of motion of our AFOs on the sagittal plane kinematics and kinetics of adolescents with diparetic cerebral palsy while walking with a powered-knee knee-ankle-foot orthosis. It is hypothesized that individuals with diparetic cerebral palsy using a powered knee-ankle-foot orthosis actuating the knee will experience reduced knee flexion (crouch) with an articulated AFO compared to a rigid AFO. Mechanical testing trials were undertaken to evaluate the linear and rotational stiffness of adjustable ankle joints positioned medially on several articulated AFOs. Quantifiable joint metrics were determined and used as a reference for the AFO stiffness experienced by participants during the pilot study. Of the kinematic and kinetic results, overall reduction in crouch gait was seen while using the powered knee-ankle-foot orthosis, and the greatest improvement was seen while using articulated AFOs. Of these trials, the articulated AFO with the lowest stiffness and that allowed for 5◦ plantar flexion and 15◦ dorsiflexion resulted in the greatest improvement in knee extension during mid-stance. This study will influence future considerations of AFO prescriptions in populations using robotic assistive devices.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".