Manual Dexterity Impairment in Patients with Complete Paraplegia: An Exploratory Study

Area of Science:

• Neuroscience
• Rehabilitation Medicine
• Motor Control

Background:

• Spinal cord injury (SCI) disrupts sensorimotor function below the lesion.
• Supralesional circuits may undergo reorganization after SCI, potentially affecting upper extremity motor control.
• Subclinical alterations in fine motor skills of the upper extremities in paraplegia are not well understood.

Purpose of the Study:

• To compare manual dexterity using the Purdue Pegboard Test between individuals with SCI and healthy subjects.
• To investigate potential subclinical deficits in upper extremity fine motor skills following SCI.

Main Methods:

• 18 individuals with SCI and 18 matched healthy subjects participated.
• The Purdue Pegboard Test, assessing dominant hand, non-dominant hand, bimanual, and assembly tasks, was administered.
• Statistical analyses included mixed ANOVA and independent samples t-tests; correlations were examined using Spearman's rho.

Main Results:

• Individuals with SCI exhibited significantly lower scores across all Purdue Pegboard Test subtests compared to healthy subjects.
• While unilateral and bimanual tasks correlated, individuals with SCI showed greater reliance on non-dominant hand ability for bimanual tasks.
• The assembly task's performance in individuals with SCI was strongly dependent on all other subtest scores, more so than in healthy subjects.
• Ageing influenced subtest performance in the SCI group.

Conclusions:

• Individuals with SCI, despite clinically normal upper extremity strength and sensation, display impaired manual dexterity.
• This impairment may stem from reduced ascending somatosensory input and neuroplastic changes in supralesional motor pathways.
• Findings suggest potential new avenues for rehabilitation in individuals with SCI.