Physiotherapy rehabilitation in subjects diagnosed with Subacromial Impingement Syndrome does not normalize shoulder muscle onset time of activation

Descriptive data of onset time of activation:

Subacromial Impingment Syndrome (SIS) rehabilitation programs targets better physical clinical outcomes and movement patterns, clinicians suggest that resolution of altered movement is related to normalizing neuromuscular patterns. Changes in onset time of activation patterns and changes in clinical outcomes could improve our understanding of suitable rehabilitation strategies. Prospective longitudinal study, we examined neuromuscular firing patterns and clinical features before and after a standardised physiotherapy program in subjects diagnosed with SIS. Electromyography (EMG) recordings of eleven shoulder muscles were taken at the initial and discharge consultation in 34 volunteers diagnosed with SIS. EMG recording was performed during flexion, scaption, and abduction at slow, medium, and fast speeds with a loaded (3kg) and unloaded arm, as well as rotational motion, rotational strength, pain, shoulder function. Resulted showed inconsistent differences of onset time of activation - mainly in some periscapular muscles in all movements. No differences were seen of the EMG recordings for rotator cuff muscles. Differences in all clinical features were shown. Despite changes in onset time of activation, the study has not been able to demonstrate consistent changes of onset time of activation of the periscapular and rotator cuff muscles. Although, completion of standardized shoulder physiotherapy program for SIS resulted in improvements in clinical outcomes.