Carpal tunnel syndrome in manual wheelchair users with spinal cord injury: a cross-sectional multicenter study.
OBJECTIVE
To investigate relationships between carpal tunnel syndrome, functional status, subject demographics, physical examination findings, and median nerve conduction study findings in manual wheelchair users with paraplegia.


DESIGN
Multicenter cross-sectional study. One hundred twenty-six manual wheelchair-using individuals with chronic paraplegia answered self-administered questionnaires on demographics, symptoms, and functional status. They underwent physical examination specific for carpal tunnel syndrome and upper-limb nerve conduction studies.


RESULTS
Fifty-seven percent of subjects had symptoms (72.2% bilateral); hand numbness was most common. Sixty percent of subjects had carpal tunnel syndrome physical examination findings (59.2% bilateral). Those with physical examination findings were more likely to have longer duration of injury (P = 0.003). Seventy-eight percent of subjects had electrophysiologic evidence of median mononeuropathy. Symptomatic subjects had significantly greater median-ulnar motor latency difference in the dominant hand (P = 0.02) and smaller compound muscle action potential amplitudes bilaterally (dominant hand, P = 0.01; nondominant hand, P = 0.04). Persons with carpal tunnel syndrome symptoms and physical examination findings had significantly worse functional status (symptoms, P < 0.001; physical examination, P = 0.02) and symptom severity scores (symptoms, P < 0.001; physical examination, P = 0.01), but a similar difference between subjects with and without median mononeuropathy was not seen. Logistic regression analysis revealed that the presence of symptoms was predicted by median-ulnar motor latency difference in the dominant hand (odds ratio, 4.38; 95% confidence interval 1.72-11.14) and sensory nerve action potential amplitude in the nondominant hand (odds ratio, 0.97; 95% confidence interval, 0.94-0.99).


CONCLUSIONS
The interaction among symptoms, physical examination, and nerve conduction study findings is complex. Carpal tunnel syndrome and median mononeuropathy are highly prevalent and functionally significant. This study highlights the need for primary prevention and patient education for preserving upper-limb function.