Altered mechanical somatosensory processing in young people with cerebral palsy: A multisite quantitative sensory testing study.

Pain is highly prevalent in young people with cerebral palsy (CP), yet the underlying somatosensory mechanisms remain poorly understood. Quantitative sensory testing (QST) offers a standardised approach to characterising sensory function and identifying altered sensory processing. This cross-sectional study aimed to describe mechanical somatosensory profiles in adolescents and young adults with CP and examine relationships between QST findings and self-reported pain measures. Thirty five participants with CP aged 8-25 years underwent a modified German Research Network on Neuropathic Pain (DFNS) QST protocol across three Australian sites. Mechanical detection threshold (MDT), mechanical pain threshold (MPT), mechanical pain sensitivity (MPS), dynamic mechanical allodynia (DMA), wind up ratio (WUR), vibration detection threshold (VDT), and pressure pain threshold (PPT) were assessed at standardised body sites. Participant scores were converted to age and sex referenced z-scores. Pain and psychosocial outcomes were assessed using validated questionnaires. Group level findings demonstrated elevated MDT, MPT, and MPS relative to normative reference data, suggesting a pattern of raised sensory thresholds coexisting with amplified suprathreshold pain sensitivity. WUR was reduced at the group level, while DMA, VDT, and PPT showed minimal deviation. Marked heterogeneity in individual sensory profiles was observed. QST parameters showed minimal association with self reported pain intensity, psychological distress, or motor severity. Together, these findings indicate that young people with CP demonstrate altered mechanical somatosensory processing and that QST and self-report questionnaires capture distinct dimensions of pain experience, supporting the need for multimodal pain assessment in CP. PERSPECTIVE: This study characterises mechanical somatosensory profiles in young people with cerebral palsy using quantitative sensory testing, revealing elevations in sensory thresholds and suprathreshold pain sensitivity. The disconnect between QST and self-reported pain suggests these measures capture distinct pain constructs, with implications for targeted pain assessment and treatment in this population.