Related Experiment Video
Updated: Sep 30, 2025
Segmentation and Linear Measurement for Body Composition Analysis using Slice-O-Matic and Horos
Published on: March 21, 2021
Can the Rhomboid Major Muscle Be Used to Identify the Thoracic Spinal Segment on Ultrasonography? A Prospective
Haesun Jung1,2, Junyeol Bae2,3, Jungsoo Kim2,4
1Department of Anesthesiology and Pain Medicine, Chung-Ang University Hospital, Seoul, Republic of Korea.
Objective:
We investigated the thoracic segment corresponding to the inferior margin of the rhomboid major muscle (RMM) using ultrasound (US) to evaluate its potential as a reliable anatomic landmark for segment identification.
Design:
A prospective observational study.
Setting:
An operating room.
Subjects:
Patients who underwent procedures around the thoracic spine.
Methods:
Four hundred segments corresponding to the RMM's inferior margin were identified through the use of paravertebral sagittal US and confirmed by fluoroscopy in 100 participants in the prone position with upward and downward shoulder rotation, comprising four datasets (up-right, up-left, down-right, and down-left). The US identification of the RMM's inferior margin was dichotomously scored (clear vs ambiguous). Each dataset was divided into two groups (dominant segment group vs remaining segments group), which were compared. Factors relevant to the dominant segment associated with the RMM's inferior border were determined through univariable analyses.
Results:
The T6 segment was observed most commonly (59.5%) along the RMM's inferior border on paravertebral sagittal US acquired in the prone position, followed by T5 (25.0%), T7 (12.8%), and T4 (2.7%). The segments corresponding to the RMM remained unchanged by shoulder posture in most participants (n = 74, 74%). The RMM's inferior border was clearly distinguishable in 330 cases (82.5%). When the RMM's inferior border was clearly identified, the corresponding segment was likely to match T6 in all datasets, with odds ratios ranging from 3.24 to 6.2.
Conclusions:
The RMM's inferior border over the transverse process corresponded to T6 most frequently on paravertebral sagittal US, and its deep fascia was clearly visible in most cases.
Related Concept Videos
01:17Ultrasonography
During an ultrasonography procedure, a handheld device called...
01:26Endoscopic Studies II: Thoracocentesis
Description
Excess pleural fluid or air may accumulate in some respiratory disorders in the thoracic cavity. To treat pleural effusion, a physician conducts thoracentesis by carefully piercing the chest wall and entering...
01:24Imaging Studies II: Ultrasonography
01:23Muscles of the Shoulder
Anterior Thoracic Muscles
The anterior thoracic muscles include the serratus anterior, subclavius, and...
01:20Ultrasound I: Abdominal Ultrasonography
Abdominal ultrasonography, commonly known as abdominal ultrasound, is a vital, non-invasive medical imaging technique widely used in healthcare.
Procedure:
This diagnostic tool allows the clinician to visually inspect internal structures within the abdomen, including vital organs such as the liver, gallbladder, pancreas, kidneys, and spleen.
The abdominal ultrasound process begins with applying a special gel to the patient's skin over the abdomen. This gel enhances the...