Path tree analysis as a tool for describing motor recovery following acquired brain injury: an exploratory study

Knowledge of the likely sequence of motor recovery following brain injury has obvious usefulness within rehabilitation. Research has tended to focus on establishing the linearity of the recovery sequence. This study aimed to ascertain the usefulness of path tree analysis as a graphical means of exploring inter-subject variation in routes followed during motor recovery.

Data were collected via physiotherapist questionnaire, ascertaining recovery sequence of 14 motor milestones across 80 adults with severe traumatic brain injury (TBI). An adapted version of the Rivermead Mobility Index (RMI) was used. Data were analysed to establish inter-subject agreement regarding recovery sequence. A path tree diagram was then composed to explore inter-subject variation.

Putative order of recovery for the 14 motor milestones appeared to have face validity. Guttman coefficients of reproducibility ((0.954) and scalability (0.948) were good, suggesting intrinsic order. Composition of a path tree suggested considerable variation in recovery paths between individuals, with 34 combinations of test items being evident.

Motor recovery following severe TBI follows a distinct pattern, but path tree analysis emphasises the variety of routes which individuals can follow. Additional research should ascertain the scope of this method to document the natural history of the recovery process.