Physiotherapy research international : the journal for researchers and clinicians in physical therapy · 2026
Effects of C3/C4 Manual Decompression on Scapular Posterior Tilt, Lower Trapezius Muscle Activity, and Strength in Individuals With Lower Trapezius Weakness.
СтатьяНазвание и аннотация: Перевод пока не подготовлен
Обработка статьи · этапы, ошибки и управление
Загрузка состояния…
Ошибки и ограничения
История · было → стало
Состояние обновляется каждые 5 секунд, пока блок открыт. Процент показывается только там, где известен объём работы. Пауза останавливает продолжение этапа; текущий запрос к источнику может завершиться.
Jung Kyung-Hee, Kwon Oh-Yun, Choi Woochol Joseph, Lim One-Bin, Moon Il-Young, Yi Chung-Hwi
Аннотация
BACKGROUND AND PURPOSE: Lower trapezius (LT) weakness-induced anterior scapular tilt is a key mechanism of shoulder dysfunction. Although the primary motor innervation of the trapezius originates from the spinal accessory nerve, cervical nerve branches (C3/C4) contribute sensory and accessory motor fibers, leading to hypotheses that C3/C4 segmental sensitivity may be associated with altered LT performance. We aimed to investigate the immediate effects of C3/C4 manual decompression on scapular posterior tilt (SPT) kinematics, LT activity, and maximal isometric strength.
METHODS: Twenty-seven participants with functional LT weakness and C3/C4 tenderness were enrolled in this single-group pretest-posttest study. Active SPT was quantified as acromial vertical displacement during prone scapular posterior tilting. Neuromuscular control was assessed by the vertical drop in arm height during a 10-s prone arm lifting task. LT activity (% MVIC) and maximal strength (kg) were assessed using surface electromyography and a KEMA sensor. A 5-min C3/C4 manual decompression was administered. Data were analyzed using a paired t-test.
RESULTS: After the intervention, active SPT increased by 10.49% (p = 0.004, d = 0.60). Vertical drop distance decreased by 50.82% (p < 0.001, d = 2.12). LT muscle activity improved by 20.61% (p < 0.001, d = 1.17). LT maximal isometric strength increased by 24.29% (p < 0.001, d = 1.65).
DISCUSSION: C3/C4 manual decompression was followed by immediate, short-term improvements in scapular control, LT muscle activity, and isometric strength in individuals with functional LT weakness. These findings provide a preliminary rationale for further investigation of this cervical intervention as an adjunctive strategy pending confirmation in controlled trials. However, given the uncontrolled study design, these results reflect overall immediate post-intervention responses and cannot confirm specific neurophysiological mechanisms or nerve-root decompression. Randomized controlled trials incorporating sham comparisons are required.
METHODS: Twenty-seven participants with functional LT weakness and C3/C4 tenderness were enrolled in this single-group pretest-posttest study. Active SPT was quantified as acromial vertical displacement during prone scapular posterior tilting. Neuromuscular control was assessed by the vertical drop in arm height during a 10-s prone arm lifting task. LT activity (% MVIC) and maximal strength (kg) were assessed using surface electromyography and a KEMA sensor. A 5-min C3/C4 manual decompression was administered. Data were analyzed using a paired t-test.
RESULTS: After the intervention, active SPT increased by 10.49% (p = 0.004, d = 0.60). Vertical drop distance decreased by 50.82% (p < 0.001, d = 2.12). LT muscle activity improved by 20.61% (p < 0.001, d = 1.17). LT maximal isometric strength increased by 24.29% (p < 0.001, d = 1.65).
DISCUSSION: C3/C4 manual decompression was followed by immediate, short-term improvements in scapular control, LT muscle activity, and isometric strength in individuals with functional LT weakness. These findings provide a preliminary rationale for further investigation of this cervical intervention as an adjunctive strategy pending confirmation in controlled trials. However, given the uncontrolled study design, these results reflect overall immediate post-intervention responses and cannot confirm specific neurophysiological mechanisms or nerve-root decompression. Randomized controlled trials incorporating sham comparisons are required.