Projected AR Serious Game “Painting Discovery” for Shoulder Rehabilitation: Assessment With Technicians, Physiotherapists, and Patients

Objective: Motivation and adherence are crucial for effective rehabilitation, yet engagement remains a challenge in upper limb physiotherapy. Serious Games (SGs) have emerged as a promising tool to enhance patient motivation. This study evaluates Painting Discovery, a projected augmented reality (AR) SG for shoulder rehabilitation, assessing engagement, ergonomics, and its potential to differentiate motor performance between healthy and those with rheumatoid arthritis, bursitis, subacromial impingement, rotator cuff tear, or calcific tendinopathy. Additionally, it examines improvements in pathological subjects following physiotherapy. Method: Sixteen healthy and seven pathological subjects participated. Engagement, ergonomics, and satisfaction were assessed using Likert-scale questionnaires. Motor performance was evaluated through completion time, speed, acceleration, and normalized jerk. Four pathological subjects underwent pre- and post-physiotherapy assessments over six weeks. Results: SG was highly engaging and ergonomic, with no significant differences based on prior video game or AR experience. The pathological group had longer completion times ( 56.49± 37.85 s vs. 39.02 ± 24.21 s, p < 0.001), lower acceleration ( 1.11 ± 0.92 m/s2 vs. 0.79 ± 0.56 m/s2, p < 0.001), and higher jerk ( 6.68 × 107 ± 1.37 × 108 m/s3 vs. 9.22 × 106 ± 2.51 × 107 m/s3, p = 0.025) then healthy subjects. After physiotherapy, completion time and normalized jerk indicated enhanced efficiency and control. Conclusions: Painting Discovery shows strong potential as an engaging, accessible rehabilitation tool. While effective in differentiating motor impairments, its small sample size and horizontal-plane movement focus limit broader conclusions. Future studies should expand participation, incorporate vertical-plane movements, and refine performance metrics for clinical validation.