Effect of different cranio-cervical positions on abdominal and back muscles activities from different postures: A cross-section study

The aim of this study was to investigate whether changing cranio-cervical postures is associated with changes in abdominal and back muscle activities during bridging and plank positions, and to present the importance of cranio-cervical posture control during trunk stabilization exercises. This was a cross-sectional study that included thirty patients (21 men and 9 women), aged between 18 and 30 years, with no history of previous spinal surgery, other severe musculoskeletal disorders, or neurological disorders, selected from Cairo University's Faculty of Physical Therapy. Every patient was requested to adopt a bridging and a plank position. Surface Electromyography (EMG) was used to assess muscular activation patterns by measuring muscle activity amplitudes. EMG signals of rectus abdominus and lumbar erector spinae in different cranio-cervical postures (extension 25°, neutral, and flexion 25°) were compared. The cranio-cervical posture was controlled utilizing a cervical range of motion device (CROM). Cranio-cervical posture was found to significantly influence trunk muscle activities (p=0.001), with cranio-cervical flexion yielding the highest activity in the rectus abdominus in both bridging (p=0.001) and plank positions (p=0.001), while cranio-cervical extension yielded the highest activity in the lumbar erector spinae in both bridging (p=0.001) and plank positions (p=0.017). Cranio-cervical flexion increased rectus abdominus muscle activity during the bridging and plank positions, while cranio-cervical extension improved lumbar erector spinae muscle activity during the bridging and plank positions. Consideration of cranio-cervical posture is suggested when carrying out trunk stabilization exercises.