Effect of Glenohumeral Internal Rotation Deficit on Shoulder Endurance and Stability in Adolescent Male Volleyball Players

NCT07372274 | Completed

• 1 other identifier: 2024-534
• Study Type: observational
• Target: 52
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to investigate whether glenohumeral internal rotation deficit (GIRD) is associated with shoulder endurance and functional stability in male adolescent volleyball players aged 14 to 18 years who do not have shoulder pain. GIRD refers to a reduction in internal rotation range of motion of the dominant (spiking) shoulder compared with the non-dominant shoulder and is commonly observed in young athletes participating in overhead sports such as volleyball. Participants will be divided into two groups based on shoulder range of motion measurements. Athletes with a loss of at least 10 degrees of internal rotation in the dominant shoulder compared to the non-dominant shoulder will be classified as having GIRD, while those without this difference will be classified as not having GIRD. Shoulder internal and external rotation range of motion will be measured using standardized clinical assessment methods. Shoulder endurance and upper extremity functional stability will then be evaluated using clinically applicable performance-based tests, including the Shoulder Endurance Test, the Posterior Shoulder Endurance Test, and the Modified Closed Kinetic Chain Upper Extremity Stability Test. The results of these tests will be compared between athletes with and without GIRD. The main research question of this study is whether the presence of GIRD in asymptomatic adolescent volleyball players is associated with reduced shoulder muscle endurance and decreased functional stability of the upper extremity. The study hypothesizes that athletes with GIRD will demonstrate lower posterior shoulder endurance and poorer upper extremity stability compared to athletes without GIRD.

Conditions

Glenohumeral Internal Rotation Deficit (GIRD)

Keywords

Glenohumeral internal rotation deficit; adolescent athletes; volleyball players

Outcome Measures

Primary Outcomes (1)

• Shoulder Endurance Test (SET) Duration

  Shoulder endurance measured as time to volitional fatigue (seconds) during the Shoulder Endurance Test. Participants stand with the back against a wall and perform repeated movements from 90° shoulder flexion to 90° abduction with 90° external rotation and back, using a 1-m green TheraBand anchored to achieve \~100% elongation. Cadence is metronome-controlled and progressively increased (60 bpm, then 90, 120, and 150 bpm). Score range: 0 seconds to no upper limit; higher seconds indicate better endurance.

  Through study completion, an average of 1 year

Secondary Outcomes (2)

• Posterior Shoulder Endurance Test (PSET) Duration

  through study completion, an average of 1 year

• Modified Closed Kinetic Chain Upper Extremity Stability Test (Modified CKCUEST) Score

  through study completion, an average of 1 year

Study Arms (2)

Glenohumeral internal rotation deficit (GIRD) Group

GIRD Present (≥10° internal rotation deficit)

Other: Glenohumeral Rotation ROM, Shoulder Endurance, and Upper Extremity Stability Testing

Non-Glenohumeral internal rotation deficit (GIRD) Group

No GIRD (\<10° internal rotation deficit)

Other: Glenohumeral Rotation ROM, Shoulder Endurance, and Upper Extremity Stability Testing

Interventions

Glenohumeral Rotation ROM, Shoulder Endurance, and Upper Extremity Stability Testing OTHER

Participants undergo a standardized shoulder assessment session. Glenohumeral internal and external rotation range of motion is measured using a goniometric clinical procedure with the shoulder positioned in standardized alignment. Functional performance is assessed using a battery of tests including a shoulder endurance test, a posterior shoulder endurance test, and a modified closed kinetic chain upper extremity stability test. All procedures are performed in a controlled laboratory setting by trained assessors following a consistent protocol.

Glenohumeral internal rotation deficit (GIRD) Group; Non-Glenohumeral internal rotation deficit (GIRD) Group

Eligibility Criteria

• Age: 14 Years - 18 Years
• Gender Eligibility Details: Eligibility is limited to individuals who are biologically male.
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

The study population consists of adolescent male volleyball players aged 14-18 years with at least 3 years of licensed volleyball experience.

You may qualify if:

• Male adolescent volleyball players aged 14-18 years
• Be a licensed volleyball player for at least 3 years.
• Be male and currently without shoulder symptoms (no current shoulder complaint)

You may not qualify if:

• Signs of possible shoulder impingement: 3 or more positive results out of 5 clinical shoulder tests (Neer test, Hawkins-Kennedy test, Painful Arc test 60°-120°, infraspinatus weakness, Empty Can test)
• Shoulder pain within the last 6 months.
• A history of shoulder surgery

Sponsors & Collaborators

• Saglik Bilimleri Universitesi: lead

Study Sites (1)

Faculty of Physiotherapy and Rehabilitation, University of Health Sciences

Ankara, Ankara, 06010, Turkey (Türkiye)

Location

Study Officials

• Seda Bicici Ulusahin, PhD

  Saglik Bilimleri Universitesi

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator, PT PhD

Study Record Dates

• First Submitted: January 13, 2026
• First Posted: January 28, 2026
• Study Start: November 5, 2024
• Primary Completion: October 30, 2025
• Study Completion: December 30, 2025
• Last Updated: January 28, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)