Research Review: Altered trapezius recruitment pattern in individuals with subacromial impingement

By Stefanie DiCarrado DPT, PT, NASM CPT & CES

Edited by Brent Brookbush DPT, PT, MS, PES, CES, CSCS, ACSM H/FS

Original Citation: Cools, A.M., Witvrouw, E.E., Declercq, G.A., Danneels, L.A., Cambier, D.C. (2003) Scapular muscle recruitment patterns: Trapezius muscle latency with and without impingement symptoms. The American Journal of Sports Medicine 31(4). 542-549 - ABSTRACT

The trapezius muscle is a superifical muscle with 3 different "segments" - upper, middle, and lower. All three assist with scapular upward rotation but differ in their ability to elevate, retract, and depress the scapula (respectively).

Why is this relevant?: Chronic shoulder pain due to subacromial impingement syndrome (SIS) is considered one of the most common dysfunctions among overhead athletes (1,2,3).  This population is most susceptible to SIS as repetitive compression and subsequent irritation of the supraspinatus tendon, subacromial bursa, and long head of the biceps tendon can occur with arm elevation.  Proper glenohumeral (GH) and scapulothoracic (ST) mechanics are necessary to reduce, eliminate, and prevent SIS (4,5). This indicates the need to understand both arthokinematics and osteokinematics as well as the muscles that impose forces across both joints.

Study Summary

Study DesignProspective Cohort Study
Level of EvidenceIIa: Evidence from at least one controlled study without randomization
Subject Demographics

  • Age:

    • SIS Group: 25.9 yrs (mean)
    • Controls (CON): 22.4 yrs (mean)
  • Gender:

    • SIS Group: 26 males, 13 females
    • CON: 19 males, 11 females
  • Characteristics: overhead athletes from a variety of sports (swimming, tennis, volleyball, other)
  • Inclusion Criteria:  at least 2/5 of the following: + Neer, + Hawkins Kennedy, + Jobe's (Empty Can), + Apprehension &