LAUSR

OBJECTIVE To identify how individuals respond to unilateral upper extremity peripheral nerve injury via compensation (increased use of the non-dominant hand). We hypothesized that injury to the dominant hand would have a greater impact on hand usage (left vs. right choices). We also hypothesized that compensation would not depend on current (post-injury) non-dominant hand performance, because many patients undergo rehabilitation that is not designed to alter hand usage. DESIGN Observational survey, single-arm. SETTINGS Academic research institution and referral center. PARTICIPANTS 48 adults with unilateral upper extremity peripheral nerve injury. Another 14 declined participation. Referred sample, including all eligible patients from 16 months at one nerve injury clinic and one hand therapy clinic. INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Hand usage (% of actions with each hand) via Block Building Task. Dexterity via Jebsen-Taylor Hand Function. RESULTS Participants preferred their dominant hand regardless of whether it was injured: hand usage (dominant/non-dominant) did not differ from typical adults, regardless of injured side (p > 0.07), even though most participants (77%) were more dexterous with their uninjured non-dominant hand (mean asymmetry index -0.16 ± 0.25). The Block Building Task was sensitive to hand dominance (p = 2.0 × 10-4), and moderately correlated with Motor Activity Log amount scores (r2 = 0.33, p = 2.9 × 10-5) . Compensation was associated only with dominant hand dexterity (p = 3.9 × 10-3), not on non-dominant hand dexterity, rehabilitation, or other patient/injury factors (p > 0.1). CONCLUSIONS Peripheral nerve injury patients with dominant hand injury do not compensate with their unaffected non-dominant hand, even if it is more dexterous. For the subset of patients unlikely to recover function with the injured hand, they could benefit from rehabilitation that encourages compensation with the non-dominant hand.