"Self‐care selfies": Patient‐uploaded videos capture meaningful changes in dexterity over 6 months.

Objective: Upper extremity function reflects disease progression in multiple sclerosis (MS). This study evaluated the feasibility, validity, and sensitivity to change of remote dexterity assessments applying human pose estimation to patient‐uploaded videos. Methods: A discovery cohort of 50 adults with MS recorded "selfie" videos of self‐care tasks at home: buttoning, brushing teeth, and eating. Kinematic data were extracted using MediaPipe Hand pose estimation software. Clinical comparison tests were grip and pinch strength, 9 hole peg test (9HPT), and vibration, and patient‐reported dexterity assessments (ABILHAND). Feasibility and acceptability were evaluated (Health‐ITUES framework). A validation cohort (N = 35) completed 9HPT and videos. Results: The modality was feasible: 88% of the 50 enrolled participants uploaded ≥3 videos, and 74% completed the study. It was also usable: assessments easy to access (95%), platform easy to use (97%), and tasks representative of daily activities (86%). The buttoning task revealed four metrics with strong correlations with 9HPT (nondominant: r = 0.60–0.69, dominant: r = 0.51–0.57, P < 0.05) and ABILHAND (r = −0.48, P = 0.05). Retest validity at 1 week was stable (r > 0.8). Cross‐sectional correlations between video metrics and 9HPT were similar at 6 months, and in the validation cohort (nondominant: r = 0.46, dominant: r = 0.45, P < 0.05). Over 6 months, pinch strength (5.8–5.0 kg/cm2, P = 0.05) and self‐reported pinch (ABILHAND) decreased marginally. While only 15% of participants worsened by 20% on 9HPT, 70% worsened in key buttoning video metrics. Interpretation: Patient‐uploaded videos represent a novel, patient‐centered modality for capturing dexterity that appears valid and sensitive to change, enhancing its potential to be disseminated for neurological disease monitoring and treatment. [ABSTRACT FROM AUTHOR]