The influence of breathing type, expiration and cervical posture on the performance of the craniocervical flexion test in healthy subjects
From: Manual Therapy. 2008 Jun;13(3):232-8. Epub 2007 Mar 23
The craniocervical flexion test is used as a clinical evaluation tool for the deep neck flexors. The influence of breathing type, expiration and cervical posture on the performance of the test is evaluated in asymptomatic subjects. Thirty volunteers participated in the study and were classified according to their breathing type: costo-diaphragmatic breathing type and upper costal breathing type. Sternocleidomastoid electromyographic activity was recorded during five incremental levels of craniocervical flexion during normal breathing as well as during expiration. The craniovertebral angle of each subject was measured to quantify cervical posture. During normal inspiration, higher electromyographic activity of the sternocleidomastoid muscles was observed in subjects with an upper costal breathing pattern compared to costo-diaphragmatic breathing subjects. This difference was statistically significant at the three lowest stages of the test. In the upper costal breathing group a significantly lower electromyographic activity of the sternocleidomastoid muscles was observed while performing the craniocervical flexion test during slow expiration compared to normal breathing. No significant correlation was found between the craniovertebral angle and the electromyographic activity of the sternocleidomastoid muscles. Performing the craniocervical flexion test during slow expiration diminishes the activity of the sternocleidomastoid muscles in subjects with a predominantly upper costal breathing pattern. Using a costo-diaphragmatic breathing pattern while performing the test will optimize the performance. Studies on neck pain patients are required to further clarify this issue.
