A collaborative research effort by Dr. Phil McClure, Dr. Kshamata Shah, and Dr. Daniel Safford of Arcadia University’s Department of Physical Therapy, and colleagues from other universities was published in the Journal of Shoulder and Elbow Surgery. This research sheds new light on how the nervous system responds to treatment in patients with subacromial pain syndrome (SAPS), which is a common source of chronic shoulder pain.

The study followed 43 patients diagnosed with SAPS, tracking changes in muscle activation, strength, pain, and function across three time points: before treatment, immediately after a subacromial injection, and after a six-week exercise program. Compared to 44 healthy control subjects, those with SAPS demonstrated significantly lower shoulder strength and impaired voluntary activation of the infraspinatus, a key rotator cuff muscle.

Researchers observed that the injection produced immediate improvements in muscle activation, which remained stable following the exercise intervention. Strength and function improved consistently, while pain levels dropped significantly over time.

The findings suggest that shoulder pain disrupts the brain’s ability to fully activate muscles, but that this disruption can be reversed. The research points to the value of incorporating neuro-focused strategies, such as motor-control training, biofeedback, or neuromuscular stimulation, into rehabilitation programs to optimize recovery.

Check out the full article here.