Peer-reviewed article
Knee proprioception in children with spastic cerebral palsy: an observational study.
Ericson A, Bartonek Å, Luis I, Eriksson M, Lidbeck C ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This peer-reviewed study examined knee proprioception (sense of body position) in 57 children with spastic cerebral palsy aged 6-18 years compared to typically developing children. Researchers used motion analysis to measure how accurately children could reproduce and maintain a knee angle at 45 degrees with eyes closed. Children with cerebral palsy showed greater difficulty than typically developing children in maintaining passively positioned knee angles, with increased movement fluctuations.
Key points
- Children with unilateral spastic CP had greater joint position sense errors than those with bilateral spastic CP
- All children with CP showed increased knee flexion and greater movement fluctuations when maintaining a passively positioned knee angle compared to typically developing children
- Children with bilateral CP demonstrated greater difficulty maintaining passively positioned leg positions over time, with increased drift towards knee flexion
- Different proprioceptive deficits appeared depending on whether CP was unilateral or bilateral
Limitations
This is a descriptive observational study that identifies differences in proprioceptive function but cannot explain causation or test an intervention to improve outcomes. The study does not evaluate whether these proprioceptive differences can be addressed or whether addressing them would improve children's functional abilities.
Abstract
Background Proprioception, the sense of body position and movement, is vital for motor control but has been sparsely explored in children with cerebral palsy (CP), particularly in the lower extremities. This study explored proprioception as the capacity to reproduce and maintain a knee flexion angle in children with CP. Methods Fifty-seven children aged 6-18 years with spastic CP; 20 unilateral (USCP), and 37 bilateral (BSCP), at Gross Motor Function Classification System (GMFCS) I-IV, and 42 typically developing (TD) children participated. Three-dimensional motion analysis was used to capture knee movements during a joint position sense test performed in sitting with occluded vision. The test consisted of (i) the criterion angle (CA) trial; the leg was passively elevated to a knee flexion angle of 45 degrees (CA) by an examiner and the position was maintained by the child, and (ii) the reproduced angle (RA) trial; the angle was actively reproduced (RA) and maintained by the child. Joint position sense errors were evaluated as the difference between CA and RA. The children's capacity to maintain the leg position was measured as the difference in knee angles, fluctuations (root mean square error) and drift (linear regression). Data were analysed with non-parametric statistics. Results Joint position sense errors were greater in the USCP-group than the BSCP-group (p = 0.037), with a more extended knee in the USCP-group (p = 0.012). When maintaining the passively positioned knee angle for 2.5 s, the CP-group compared to the TD-group, showed increased knee flexion and greater movement fluctuations (p = 0.006). Within-group analysis showed increased knee flexion at the passively assumed position (CA vs. maintained for 2.5 s) compared to at the actively assumed position (RA vs. maintained for 2.5 s) in the BSCP-group (p = 0.015) and the GMFCS II-group (p = 0.028). The BSCP-group also showed increased drift over time towards knee flexion when the leg was passively compared to actively positioned (p = 0.040). Conclusions The results reveal a divergence in proprioceptive function: while the USCP-group had greater difficulty than the BSCP-group in reproducing a knee angle, the BSCP-group demonstrated greater difficulty in maintaining the knee position during passive positioning of the lower limb. Trial registration This study was observational and was therefore not registered as a clinical trial.