Advanced insights in upper limb function of individuals with cervical spinal cord injury

An important criterion for a clinical outcome measure, such as the Graded and Redefined Assessment of Strength, Sensibility and Prehension (GRASSP), is its sensitivity to detect changes in upper limb function over time. This facilitates the evaluation of recovery patterns and treatment efficacy of experimental interventions in cervical spinal cord injury (SCI). However, responsiveness has not yet been investigated and is therefore one of the aims within this thesis. In general, little has been published on prediction of functional outcome following SCI, and in particular, data on prediction and stratification of upper limb function and self-care after incomplete cervical SCI is lacking. The overall aim of this PhD thesis has been therefore to study the assessment, evaluation and prediction of upper limb function up to one year post injury using the GRASSP in individuals with cervical SCI. The GRASSP showed excellent responsiveness within the first year after cervical SCI. It detected distinct changes in strength and prehension relating to the severity of cervical SCI. GRASSP detected clinically significant changes complimentary to the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) and Spinal Cord Indepence Measure self-care subscale (SCIM-SS) assessments. The GRASSP at 1 month accurately predicted upper limb function and self-care outcomes at 6 and 12 months after cervical SCI. Unbiased recursive partitioning conditional inference tree (URP-CTREE) revealed the distribution of outcome categories and can be used to predict cohorts with homogenous outcomes. The work contained in this thesis provides advanced insights and useful data regarding upper limb function outcome in cervical SCI. Evidence was presented that the GRASSP provides information on multifaceted domains (e.g. strength, sensation and prehension) and allows to detect both subtle and clinical meaningful changes in upper limb function. Furthermore, the GRASSP can accurately predict upper limb function and activities of daily living (ADLs), even in a heterogeneous group of individuals across a wide spectrum of neurological recovery. This supports the use of the GRASSP in the assessment of rehabilitation outcome as well as in clinical studies and trials.