Min-Hyeok Kang1, Ji-Young Choi2, Jae-Seop Oh3. 1. Department of Physical therapy, Graduate School, INJE University, Gimhae, South Korea. 2. Division of Physical Therapy, Changwon Himchanhospital, Changwon, South Korea. 3. Department of Physical Therapy, College of Biomedical Science and Engineering, INJE University, 607 Obang-dong, Gimhae-si, Gyeongsangnam-do, South Korea, 621-749.
Abstract
BACKGROUND: Scapular downward rotation syndrome manifests as an abnormally downward-rotated scapula at rest or with arm motion and typically results in neck and shoulder pain. The brassiere strap has been suggested as a possible contributing factor to scapula downward rotation and pain in the upper trapezius because of increased downward rotational force on the lateral aspect of the scapula. No study, however, has examined the influences of a modified brassiere strap on pain in and the function of the scapular muscles. OBJECTIVE: To examine the effects of crossed brassiere straps on the pressure pain threshold (PPT) of the upper trapezius, neck rotation range of motion (ROM), and electromyographic activity of the scapular upward rotators in females with scapular downward rotation syndrome. DESIGN: Cross-over design. SETTING: Laboratory. PARTICIPANTS: In total, 15 female subjects with scapular downward rotation syndrome were recruited at hospitals and a local university. METHODS: All participants performed neck rotation and humeral elevation under 2 different conditions: parallel and crossed brassiere straps. MAIN OUTCOME MEASUREMENTS: The PPT of the upper trapezius was measured using an analog algometer, whereas neck rotation ROM was quantified with a 3-dimensional ultrasonic motion analysis system. The electromyographic activities of the upper trapezius, serratus anterior, and lower trapezius during humeral elevation were assessed with a surface electromyography system. Outcome measures were assessed under parallel and crossed brassiere strap conditions, and differences in outcomes between the conditions were analyzed using a paired t-test. RESULTS: The PPT and neck rotation ROM were increased when the subject was wearing the brassiere with crossed versus parallel straps (P < .001). Greater electromyographic activities of the serratus anterior, lower trapezius, and lesser upper trapezius muscles during humeral elevation were found under the crossed strap condition than the parallel strap condition (P < .05). CONCLUSIONS: These findings provide useful information for clinicians when designing management programs to decrease pain and improve biomechanical function for females with scapular downward rotation syndrome.
RCT Entities:
BACKGROUND: Scapular downward rotation syndrome manifests as an abnormally downward-rotated scapula at rest or with arm motion and typically results in neck and shoulder pain. The brassiere strap has been suggested as a possible contributing factor to scapula downward rotation and pain in the upper trapezius because of increased downward rotational force on the lateral aspect of the scapula. No study, however, has examined the influences of a modified brassiere strap on pain in and the function of the scapular muscles. OBJECTIVE: To examine the effects of crossed brassiere straps on the pressure pain threshold (PPT) of the upper trapezius, neck rotation range of motion (ROM), and electromyographic activity of the scapular upward rotators in females with scapular downward rotation syndrome. DESIGN: Cross-over design. SETTING: Laboratory. PARTICIPANTS: In total, 15 female subjects with scapular downward rotation syndrome were recruited at hospitals and a local university. METHODS: All participants performed neck rotation and humeral elevation under 2 different conditions: parallel and crossed brassiere straps. MAIN OUTCOME MEASUREMENTS: The PPT of the upper trapezius was measured using an analog algometer, whereas neck rotation ROM was quantified with a 3-dimensional ultrasonic motion analysis system. The electromyographic activities of the upper trapezius, serratus anterior, and lower trapezius during humeral elevation were assessed with a surface electromyography system. Outcome measures were assessed under parallel and crossed brassiere strap conditions, and differences in outcomes between the conditions were analyzed using a paired t-test. RESULTS: The PPT and neck rotation ROM were increased when the subject was wearing the brassiere with crossed versus parallel straps (P < .001). Greater electromyographic activities of the serratus anterior, lower trapezius, and lesser upper trapezius muscles during humeral elevation were found under the crossed strap condition than the parallel strap condition (P < .05). CONCLUSIONS: These findings provide useful information for clinicians when designing management programs to decrease pain and improve biomechanical function for females with scapular downward rotation syndrome.