Tehran University Medical Journal

Background: Sonography is used for measuring the muscle morphology including length, depth, cross-sectional area, bulk and pennation angle. The supraspinatus is the most common affected muscle among the rotator cuff muscles. There is no study about the reliability of sonographic measurement of supraspinatus thickness in the positions of empty can (EC), full can (FC) and hug up (HU) tests. The present study aims to investigate the intra-rater reliability of the measurement of sonographic thickness of supraspinatus muscle in the rest and positions of the EC, FC and HU tests.
Methods: The present study was a descriptive-analytic study which was carried out in a cross-sectional method on ten healthy women aged: 22.10±2.76 years without any tendon pathology. The study was carried out during four weeks (January to March in 2017). The supraspinatus thickness was scanned during rest and contracted states. The positions of measuring ultrasonic thickness of supraspinatus were as follow: position of EC test: the arm in 90-degree elevation in the scaption plane with the thumb-down, position of FC test: the arm in 90-degree elevation in the scaption plane with the thumb-up, position of HU test: the palm of hand was placed on the opposite shoulder with the elbow flexed using a 0.5-kg weight cuff. Intra-rater reliability of ultrasonic muscle thickness measurements were examined in one day.
Results: All intra-rater reliability values were equal or more than 0.90: the value was 0.90 (95%CI: 0.65-0.97) in the rest position, while for the measurement of ultrasonic thickness of the supraspinatus was 0.96 (95%CI: 0.87-0.99) in the position of EC test, 0.97 (95%CI: 0.90-0.99) and 0.96 (95%CI: 0.86-0.99) in the positions of FC and HU tests, respectively.
Conclusion: Measurement of ultrasonic thickness of supraspinatus muscle is a reliable method in the rest and positions of EC, FC and HU tests. This method can be used to compare the muscle thickness changes in the positions of the above tests.
 

Background:  Some studies show that frozen shoulder is due to the pathologic changes in the muscles around the shoulder. Measurement of the ultrasonic thickness of a muscle is a method for measuring the muscle changes. There is no study about the reliability of measurement of the muscle’s ultrasonic thickness around the shoulder in patients with frozen shoulder. The present study aims to investigate the intra-rater reliability of the ultrasonic thickness measurement of the supraspinatus, deltoid and upper trapezius muscles in women with frozen shoulder and healthy women.
Methods: This study was carried out during 4 months (June to October 2017). Twenty women consisted of 10 patients with frozen shoulder (mean age: 51.6±9.41 years) and 10 healthy subjects (mean age: 35.5±8.22 years) participated in this study. The patients from some clinics and hospitals in Tehran, and healthy subjects consisted of some personals and students in the School of Rehabilitation of Shahid Beheshti university of Medical Sciences participated in the present study. Measurements of ultrasonic thickness of the upper trapezius, supraspinatus and deltoid muscles in rest position carried out by the same rater two times in 48 hours. Ultrasonography instrument with linear probe (frequency: 7.5 MHz) were used for measurement of muscle thickness in millimeter.
Results: Reliability of the ultrasonic measurements of the muscle thickness in patients and healthy subjects was respectively as follow: The upper trapezius muscle (0.81, 0.81), the supraspinatus muscle (0.90, 0.92) and the middle deltoid muscle (0.93, 0.96). The reliability of the ultrasonic measurements of the muscle thickness for the upper trapezius muscle and the supraspinatus muscle was higher in healthy subjects compared to the patients with frozen shoulder. The reliability of the ultrasonic measurements of the middle deltoid thickness for the patients and healthy subjects was similar.
Conclusion: It seems that ultrasonography is a reliable method for measuring the thickness of the muscles around the shoulder in patients with frozen shoulder and healthy subjects.

Background: Rotator cuff injuries are the most common causes of shoulder pain and supraspinatus muscle is usually involved. Clinical tests are available and inexpensive tools for assessment of shoulder dysfunctions. The empty can (EC) and full can (FC) tests are considered as shoulder gold standard tests. Recently, hug up (HU) test has been developed to assess the supraspinatus. So far, no ultrasonographic study has compared supraspinatus muscle thickness in these testing positions. The present study aimed to compare the supraspinatus muscle thickness in the hug up testing position with the full can and empty can testing positions in young and healthy women.
Methods: Forty healthy women (mean age 21.62±2.4 years) participated in this cross-sectional-comparative study from April to June 2018 in the Biomechanic Laboratory of Rehabilitation School, Shahid Beheshti University of Medical Sciences in Tehran, Iran. The supraspinatus muscle thickness was scanned during rest and contracted states with a 0.5 Kg weight cuff. For contracted states, (A) EC testing position: the arm was at 90º abduction in the scaption plane with the thumb-down, (B) FC testing position: the arm was maintained at 90º abduction in the scaption plane with the thumb-up, (C) HU testing position: the palm of hand was placed on the opposite shoulder with the elbow flexed.
Results: The Bonferroni test showed significant differences (P<0.001) between the muscle thickness in the rest and the testing positions. The muscle thickness in the empty can testing position was significantly less than the full can testing position (P=0.001), no significant difference was found between the muscle thickness in the hug up testing position compared to the full can and empty can testing positions.
Conclusion: All of the empty can, full can and hug up testing positions demonstrated increased mean muscle thickness when compared to the rest position and the greatest muscle thickness was in the full can testing position. It seems that supraspinatus muscle thickness in hug up testing position is similar with empty can and full can testing positions.