title: Motor control retraining exercises for shoulder impingement: effects on function, muscle activation, and biomechanics in young adults.
abstract: OBJECTIVE
  Evidence for effective management of shoulder impingement is limited. The present study aimed to quantify the clinical, neurophysiological, and biomechanical effects of a scapular motor control retraining for young individuals with shoulder impingement signs.
  
  
  METHODS
  Sixteen adults with shoulder impingement signs (mean age 22 ± 1.6 years) underwent the intervention and 16 healthy participants (24.8 ± 3.1years) provided reference data. Shoulder function and pain were assessed using the Shoulder Pain and Disability Index (SPADI) and other questionnaires. Electromyography (EMG) and 3-dimensional motion analysis was used to record muscle activation and kinematic data during arm elevation to 90° and lowering in 3 planes. Patients were assessed pre and post a 10-week motor control based intervention, utilizing scapular orientation retraining.
  
  
  RESULTS
  Pre-intervention, patients reported pain and reduced function compared to the healthy participants (SPADI in patients 20 ± 9.2; healthy 0 ± 0). Post-intervention, the SPADI scores reduced significantly (P < .001) by a mean of 10 points (±4). EMG showed delayed onset and early termination of serratus anterior and lower trapezius muscle activity pre-intervention, which improved significantly post-intervention (P < .05). Pre-intervention, patients exhibited on average 4.6-7.4° less posterior tilt, which was significantly lower in 2 arm elevation planes (P < .05) than healthy participants. Post-intervention, upward rotation and posterior tilt increased significantly (P < .05) during 2 arm movements, approaching the healthy values.
  
  
  CONCLUSIONS
  A 10-week motor control intervention for shoulder impingement increased function and reduced pain. Recovery mechanisms were indicated by changes in muscle recruitment and scapular kinematics. The efficacy of the intervention requires further examined in a randomized control trial.
authors.affiliation: Faculty of Health Sciences, University of Southampton, Southampton, UK. p.r.worsley@soton.ac.uk
authors.forename: Peter
authors.initials: P
authors.lastname: Worsley
authors.forename: Martin
authors.initials: M
authors.lastname: Warner
authors.forename: Sarah
authors.initials: S
authors.lastname: Mottram
authors.forename: Stephan
authors.initials: S
authors.lastname: Gadola
authors.forename: H E J
authors.initials: HE
authors.lastname: Veeger
authors.forename: Hermie
authors.initials: H
authors.lastname: Hermens
authors.forename: Dylan
authors.initials: D
authors.lastname: Morrissey
authors.forename: Paul
authors.initials: P
authors.lastname: Little
authors.forename: Cyrus
authors.initials: C
authors.lastname: Cooper
authors.forename: Andrew
authors.initials: A
authors.lastname: Carr
authors.forename: Maria
authors.initials: M
authors.lastname: Stokes
mesh_terms: D000293:Adolescent; D000328:Adult; D018771:Arthralgia / Q000503:physiopathology / Q000534:rehabilitation* / Q000628:therapy; D001696:Biomechanical Phenomena; D005081:Exercise Therapy; D005260:Female; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000503:physiopathology; D012540:Scapula / Q000503:physiopathology; D019534:Shoulder Impingement Syndrome / Q000503:physiopathology / Q000534:rehabilitation* / Q000628:therapy; D055815:Young Adult