Mental health and burnout among Swiss medical students living in contexts of deprivation: a longitudinal study.

Hemiplegic shoulder pain (HSP) is a frequent and clinically relevant complication after stroke, with reported prevalence rates ranging widely from approximately 5% to 84%, depending on diagnostic criteria, timing of assessment, and characteristics of the study population. HSP negatively affects upper-limb motor recovery, reduces functional autonomy, and promotes limb disuse, thereby contributing to long-term disability. Pain is commonly elicited during passive shoulder mobilization and may persist for months or years in a substantial proportion of patients, highlighting its detrimental impact on rehabilitation outcomes. From a pathophysiological perspective, neurological damage represents the initiating event in a cascade leading to shoulder pain. Muscle weakness, altered muscle tone, and sensory deficits disrupt normal scapulohumeral mechanics, generating a biomechanical imbalance around the glenohumeral joint. This imbalance increases mechanical stress on periarticular soft tissues – including the joint capsule, tendons, ligaments, and bursae – predisposing them to structural lesions that generate nociceptive input and contribute to the development of pain. Soft-tissue abnormalities of the hemiplegic shoulder can be effectively assessed using ultrasonography, which allows detailed and dynamic evaluation of periarticular and articular structures. Owing to its accessibility, safety, and ability to provide real-time assessment, ultrasound is considered the imaging modality of choice for investigating post-stroke shoulder pathology and its evolution over time.