The Science of Repetitive Strain Injuries

Repetitive strain injuries (RSI) develop when tissues are subjected to repeated low-level stress over extended periods, exceeding their capacity to recover between episodes of use. This creates a cycle of microtrauma and incomplete healing that gradually leads to tissue breakdown and sensitization of pain pathways. The pathophysiology involves multiple systems: musculoskeletal tissues experience microscopic damage from repetitive loading, while the nervous system becomes increasingly sensitive to normal stimuli. This process, called peripheral and central sensitization, means that activities which were once painless now trigger significant discomfort. Computer-related RSI typically affects the upper limbs through sustained postures combined with repetitive small movements. The muscles that stabilize your shoulder blade, neck, and forearm work continuously to maintain positions required for keyboard and mouse use, leading to fatigue and eventual breakdown of normal tissue architecture. Psychological factors play a significant role in RSI development and persistence. Work stress, time pressure, and fear of job security can increase muscle tension and delay recovery. The condition often becomes a complex interaction between physical tissue changes and psychological stress responses.