Immediate Effects of Different Stretching Methods for Pectoralis Minor Muscle

Comparison of Immediate Effects of Different Stretching Methods for Pectoralis Minor Muscle on Scapula Position, Pectoralis Minor Muscle Length and Scapular Muscle Activation in Individuals With Shoulder Protraction

The aim of our study is to compare the effects of different stretching methods for the pectoralis minor (PM) muscle on scapula position, PM muscle length and scapular muscle activation in individuals with shoulder protraction. Unilateral corner stretching, manual stretching and proprioceptive neuromuscular facilitation (PNF) stretching methods will be applied randomly, 2 days apart, to volunteer individuals who agree to participate in our study. Three different stretching methods (unilateral corner stretching, manual stretching and PNF stretching) will be applied to individuals randomly, 48 hours apart, and PM length, PM index, scapula upward rotation and EMG values will be recorded by a blind evaluator before and after the stretching application.

Study Overview

• Status: Recruiting
• Conditions: Rounded Shoulder Posture
• Intervention / Treatment: Other: Unilateral Corner Stretch; Other: Manual Stretching; Other: PNF Stretching

Detailed Description

Our study will include individuals who volunteer to participate in the study, and informed consent will be obtained from the individuals. Shoulder protraction will be determined according to the measurement result of the distance between the posterolateral side of the acromion and the bed in the supine position of the individual. If the distance is 2.6 centimeters or more, it will be recorded as shoulder protraction posture. PM length, PM index, upward rotation angle of the scapula at 0°, 45°, 90° and 135° abduction, electromyographic (EMG) muscle activation of the upper trapezius, middle trapezius, lower trapezius and serratus anterior muscles will be evaluated by a blind evaluator before and after the stretching methods. Unilateral corner stretching, manual stretching and proprioceptive neuromuscular facilitation (PNF) stretching methods will be applied randomly, 48 hours apart. The order of Unilateral Corner Stretching, Manual Stretching and PNF Stretching methods to be applied to individuals will be assigned with the simple allocation using random allocation. SPSS (Statistical Package for Social Sciences) version 22.0 will be used to evaluate the data obtained from the study and create tables. The Shapiro-Wilk test will be used to determine the distribution of the data. Descriptive statistics of numerical variables with normal distribution will be indicated by X ± SD, descriptive statistics of numerical variables without normal distribution will be indicated by median and (IQR), descriptive statistics of categorical variables will be indicated by frequency and percentage (%). Paired Sample T test will be used for intra-group comparison of normally distributed data and Wilcoxon test will be used for intra-group comparison of non-normally distributed data. The one-way repeated measures analysis of variance (ANOVA) will be performed to compare the three groups. The statistical significance level will be set at p<0.05 and a post-hoc multiple comparisons test with Bonferroni correction will be performed.

• Study Type: Interventional
• Enrollment (Estimated): 25
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Tuğçe Çoban, MSc; Phone Number: +905454098540; Email: fzttugce@yahoo.com

Study Locations

• Turkey
  • Çankaya
    • Ankara, Çankaya, Turkey, 06490
      • Recruiting
      • Gazi University
      • Contact: Tuğçe Çoban, MSc; Phone Number: +905454098540; Email: fzttugce@yahoo.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Having a shoulder protraction posture
• Not having had a shoulder surgery before
• Agreeing to participate in the study

Exclusion Criteria:

• Cervical or shoulder pain
• Adhesive capsulitis
• Thoracic outlet syndrome
• Shoulder instability
• Shoulder surgery history
• Numbness or tingling in the upper extremity

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Group 3; PNF Stretching	Other: PNF Stretching; Individuals will be in a sitting position with their hands clasped behind the head. The PM muscle will be stretched in the direction of horizontal abduction by placing the physiotherapist's hands anterior to the elbows. Passive stretching will be continued for 10 seconds, followed by 6 seconds of maximum voluntary isometric contraction of the PM muscle. The procedure will be repeated four times with 30 seconds of rest.
Experimental: Group 1; Unilateral Corner Stretching	Other: Unilateral Corner Stretch; Individuals will be positioned in a standing position with the elbow in 90° flexion and the shoulder in 90° abduction, placing the palm on a flat surface. For stretching, individuals will be asked to increase shoulder horizontal abduction by rotating the trunk anteriorly and contralaterally. The position will be maintained for 30 seconds and will be repeated 4 times with a 30-second rest between repetitions.
Experimental: Group 2; Manual Stretching	Other: Manual Stretching; Individuals will be positioned supine with the shoulder in 90º abduction and external rotation and the elbow in 90º flexion. Stretching will be applied by the physiotherapist from just distal to the elbow in the direction of horizontal abduction of the shoulder. The position will be maintained for 30 seconds and will be repeated 4 times with a 30-second rest between repetitions.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pectoralis Minor Length	To measure the length of the pectoralis minor muscle, the distance between the caudal corner of the 4th rib and the inferomedial face of the coracoid process will be recorded with a tape measure.	Baseline
Pectoralis Minor Length	To measure the length of the pectoralis minor muscle, the distance between the caudal corner of the 4th rib and the inferomedial face of the coracoid process will be recorded with a tape measure.	Immediately after intervention
Pectoralis Minor Index	PM index will be recorded by calculating the ratio of the pectoralis minor length to the individual's height multiplied by 100.	Baseline
Pectoralis Minor Index	PM index will be recorded by calculating the ratio of the pectoralis minor length to the individual's height multiplied by 100.	Immediately after intervention
Scapula Upward Rotation Measurement	Individuals' scapula upward rotation measurement will be evaluated with an inclinometer in the resting position, 45º, 90º and 135º shoulder abduction positions. Three measurements will be taken with a 30-second rest interval and the average value will be calculated.	Baseline
Scapula Upward Rotation Measurement	Individuals' scapula upward rotation measurement will be evaluated with an inclinometer in the resting position, 45º, 90º and 135º shoulder abduction positions. Three measurements will be taken with a 30-second rest interval and the average value will be calculated.	Immediately after intervention
EMG Analysis	Individuals' upper trapezius, middle trapezius, lower trapezius and serratus anterior muscle activations will be evaluated using superficial EMG. Measurements will be taken from the dominant side.	Baseline
EMG Analysis	Individuals' upper trapezius, middle trapezius, lower trapezius and serratus anterior muscle activations will be evaluated using superficial EMG. Measurements will be taken from the dominant side.	Immediately after intervention

Collaborators and Investigators

• Sponsor: Gazi University
• Investigators: Principal Investigator: Selda Başar, PhD, Gazi University

Publications and helpful links

General Publications

• Borstad JD, Ludewig PM. Comparison of three stretches for the pectoralis minor muscle. J Shoulder Elbow Surg. 2006 May-Jun;15(3):324-30. doi: 10.1016/j.jse.2005.08.011.
• Rosa DP, Borstad JD, Pogetti LS, Camargo PR. Effects of a stretching protocol for the pectoralis minor on muscle length, function, and scapular kinematics in individuals with and without shoulder pain. J Hand Ther. 2017 Jan-Mar;30(1):20-29. doi: 10.1016/j.jht.2016.06.006. Epub 2016 Oct 18.
• Williams JG, Laudner KG, McLoda T. The acute effects of two passive stretch maneuvers on pectoralis minor length and scapular kinematics among collegiate swimmers. Int J Sports Phys Ther. 2013 Feb;8(1):25-33.

Study record dates

Study Major Dates

• Study Start (Actual): September 11, 2023
• Primary Completion (Estimated): July 3, 2024
• Study Completion (Estimated): September 4, 2024

Study Registration Dates

• First Submitted: March 6, 2024
• First Submitted That Met QC Criteria: March 6, 2024
• First Posted (Actual): March 13, 2024

Study Record Updates

• Last Update Posted (Actual): March 13, 2024
• Last Update Submitted That Met QC Criteria: March 6, 2024
• Last Verified: March 1, 2024

More Information

Terms related to this study

• Keywords: Stretching; Pectoralis Minor; Muscle Activation
• Other Study ID Numbers: E-77082166-302.08.01-639069

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No