Does the pectoralis minor length influence acromiohumeral distance, shoulder pain-function, and range of movement?

To determine the association between pectoralis minor length (PML) and the acromiohumeral distance (AHD) in the symptomatic (S) and the asymptomatic (A) shoulder of subjects with chronic shoulder pain, and in shoulder free of pain controls (C). Furthermore, to analyze the relationship between PML and shoulder pain-function and range of movement (ROM) free of pain.

A cross sectional study.

Primary care centres.

A sample of fifty-four participants with chronic shoulder pain in their dominant arm was recruited, as well as fifty-four participants with shoulder free of pain.

PML test and AHD measured by ultrasound.

There was a non statistical significant correlation between PML and AHD for all the groups at both 0° (S = 0.03, p = 0.29; A = 0.06, p = 0.66; C = -0.17, p = 0.29) and 60° (S = -0.10, p = 0.84; A = -0.18, p = 0.19; C = -0.03, p = 0.84) of shoulder elevation. Likewise, there was a non statistical significant correlation between PML and shoulder pain-function (0.09, p = 0.52), and ROM (-0.13, p = 0.35).

PML is poorly associated with AHD, as well as with shoulder pain and mobility, in people with chronic shoulder pain. Other biomechanics alterations, as well as the presence of central/peripheral sensitization should be considered.