The Relationship Between Transversus Abdominis Muscle Architecture and Upper Extremity Function in Patients With Chronic Low Back Pain

The Relationship Between Transversus Abdominis Muscle Architecture and Upper Extremity Function in Patients With Chronic Low Back Pain: A Comparative Ultrasonographic Study

Core stability is the ability to control the position and movement of the trunk for optimal production, transfer, and control of forces in the upper and lower extremities during functional activities.

Studies have shown that TrA activation is delayed in individuals with low back pain. The relationship between core stability and the lower extremity has been frequently studied in the literature, and according to Kibler's 'Kinetic Chain' theory, loss of proximal stability is known to lead to dysfunction in distal segments; however, the relationship between the upper extremity and core stability is still unclear. The aim of our study is to investigate the upper extremity reach capacity and scapular stability of individuals with low back pain in relation to TrA involvement and to compare them with healthy individuals without low back pain.

Study Overview

• Status: Not yet recruiting
• Conditions: Low Back Pain; Ultrasound; Scapular Dyskinesis; Core Muscles; Functional Reach

Detailed Description

Core stability is the ability to control the position and movement of the trunk for optimal production, transfer, and control of forces in the upper and lower extremities during functional activities. The most important components of core stability are muscle capacity and neuromuscular control. A stable core region is effective in facilitating extremity function.

Studies have shown that TrA activation is delayed in individuals with low back pain. The relationship between core stability and the lower extremity has been frequently studied in the literature, and according to Kibler's 'Kinetic Chain' theory, loss of proximal stability is known to lead to dysfunction in distal segments; however, the relationship between the upper extremity and core stability is still unclear. In light of all this data, the aim of our study is to investigate the upper extremity reach capacity and scapular stability of individuals with low back pain in relation to TrA involvement and to compare them with healthy individuals without low back pain.

• Study Type: Observational
• Enrollment (Estimated): 90

Contacts and Locations

• Study Contact: Name: İlayda Dilan Işık, MsC; Phone Number: +905305239711; Email: ilayda_dilan06@hotmail.com

Study Locations

• Turkey (Türkiye)
  • Ankara, Turkey (Türkiye)
    • GYM Center
    • Contact: İlayda Dilan Işık, MsC; Phone Number: +905305239711; Email: ilayda_dilan06@hotmail.com

Participation Criteria

Eligibility Criteria

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

• Sampling Method: Non-Probability Sample

Study Population

The study will include individuals aged 18-45 with and without low back pain. Individuals with low back pain will be included only if they have received a diagnosis of "Non-Specific Chronic Low Back Pain" from a physician. The control group will consist of healthy individuals.

Description

Inclusion Criteria:

• Being between 18-45 years of age.
• Having a normal Body Mass Index (BMI) (18.5 - 29.9 kg/m²).
• For the painful group, having pain for a minimum of 3 months and a minimum of 3/10 pain at rest or during activity. • Not having received medical treatment for back or shoulder pain in the last 12 months for healthy control examinations.

Exclusion Criteria:

• Having neurological diseases.
• Having a diagnosed pathology and/or severe pain in the upper extremity.
• Being a professional athlete.
• Being pregnant.
• Having advanced structural spinal deformities (scoliosis, kyphosis, etc.).
• Having undergone abdominal surgery (Cesarean section is not included).
• Having undergone spinal and/or lumbar surgery.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Low Back Pain; It consists of people who have back pain.
Control Group; Healthy people without back pain

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Severity of back pain	Resting, activity, and nocturnal pains will be marked on a visual analog scale.	It will only be evaluated once.
Ultrasound	Measurements taken from the TrA muscle will first involve measuring the length of the cross-section in the resting position, then taking another measurement during the maneuver, and recording the differences between these measurements.	It will only be evaluated once.
Funcitonal Reach Test	During the measurement, the patient lies on their side against the wall (leaving a small enough distance between themselves and the wall to avoid contact). Their feet are shoulder-width apart and fixed. The patient raises the arm closest to the wall to 90 degrees of shoulder flexion (straight forward). Make a fist. While the patient's arm is at 90 degrees, the point where the head of the 3rd metacarpal (middle finger joint) aligns with the measuring tape on the wall is recorded. The patient is then asked to reach forward as far as they can without lifting their feet off the ground or taking a step. At the furthest point the patient can reach without losing their balance, the alignment of the 3rd metacarpal head is again recorded. The distance between these points is taken as the final measurement. During the measurement, it is crucial that the heels do not lift off the ground, that no steps are taken, that no support is placed against the wall, and that the arm does not drop.	It will only be evaluated once.
Kibler's Lateral Scapular Slide Test	Measurements were taken using a measuring tape to gauge the distance between the spinous processes of the spine and the inferior angulus of the scapula, and repeated in three different positions: arms free at the sides, hands on the hips (approximately 45 degrees abduction), and arms outstretched to the sides (90 degrees abduction and maximum internal rotation). Under normal conditions, the distance between these positions does not vary significantly or changes symmetrically. If the difference between the two sides is more than 1.5 cm or if there is excessive variation between positions, the diagnosis will be considered "Scapular Dyskinesia Present (+)".	It will only be evaluated once.

Collaborators and Investigators

• Sponsor: Ilayda Dilan Isik

Publications and helpful links

General Publications

• Cacolice PA, Carcia CR, Scibek JS. Shoulder Flexion Torque Is Augmented by a Volitional Abdominal Isometric Contraction. J Strength Cond Res. 2021 Apr 1;35(4):920-923. doi: 10.1519/JSC.0000000000003277.
• Roche SJ, Funk L, Sciascia A, Kibler WB. Scapular dyskinesis: the surgeon's perspective. Shoulder Elbow. 2015 Oct;7(4):289-97. doi: 10.1177/1758573215595949. Epub 2015 Jul 16.

Study record dates

Study Major Dates

• Study Start (Estimated): April 1, 2026
• Primary Completion (Estimated): June 30, 2026
• Study Completion (Estimated): August 31, 2026

Study Registration Dates

• First Submitted: March 7, 2026
• First Submitted That Met QC Criteria: March 11, 2026
• First Posted (Actual): March 16, 2026

Study Record Updates

• Last Update Posted (Actual): March 16, 2026
• Last Update Submitted That Met QC Criteria: March 11, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: low back pain; ultrasound; scapular dyskinesis; core; functional reach
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Back Pain; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Low Back Pain
• Other Study ID Numbers: AnkaraSBU3

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: We are not sure because the data does not contain personal information and may be useful in other studies.

Drug and device information, study documents

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