Does Accelerometry Reflect Hand Function in Infants at Risk of Unilateral Cerebral Palsy? A Secondary Analysis of BB-Bim Results

Background: Infants at high-risk of unilateral Cerebral Palsy (UCP) may have asymmetry in upper extremity movement and function, which should be identified as soon as possible for management. Aims: To explore the feasibility of using two AX3 Axivity monitors in wrist-worn bracelets to quantify movements, and to identify whether accelerometry parameters are consistent with hand function. Methods and procedures: 6 infants at high risk of UCP (aged 3 to -12 months) were included in a Single-Case Experimental Design to explore the impact of an 8-week bimanual stimulation home program. Outcomes: Each week of the baseline (randomized duration 4-7 weeks) and 8-week program, the Hand Assessment for Infants (HAI) was performed and accelerometry parameters were collected during HAI and also during spontaneous activity, several times a week. Results: Actimetry was analyzed during HAI and 238 spontaneous activity sessions (mean 42 & PLUSMN; 21 min). Actimetry ratios distribution and evolution show a high variability, especially for spontaneous activity. No strong correlation was found between HAI scores and accelerometry parameters, either collected during HAI, or during spontaneous activity times.Conclusion and implications: Despite its feasibility, using accelerometry bracelets looks unreliable for detecting and monitoring hand function in infants under one year.