Respiratory Synkinesis - Polyelectromyographic Investigation

Abstract

From clinical observation we knew that thoracolumbar lordosis increases during deep (maximum) exhalation both standing and seated. We regularly made use of this effect for mobilization and self-treatment in patients with rigid thoracic kyphosis. From experience we also knew that with the patient prone, i.e. in thoracolumbar lordosis, the buttocks move up during deep exhalation and that during inhalation they move in a caudal direction. If cranial movement is resisted from above, effective traction results. In both situations the possible explanation was synkinetic contraction of the back muscles, in particular of the erector spinae.

EMG examination of the back muscles was therefore carried out with the aid of surface electrodes in 30 subjects prone, with and without resistance against the cranial shift of the buttocks, and seated with the knees and the head pressed against crossed hands resting on the wall. Recordings were made at rest, during inhalation and during deep exhalation. In 12 subjects recordings were also made in kyphosis: with the trunk bent over the knees and sitting in a supported kyphotic position. EMG examination fully confirmed our assumptions: deep (maximum) exhalation regularly evoked the activity of the back muscles in lordosis: in kyphosis the activity was only slight.

key words::

• EMG. surface electrodes
• respiratory synkinesis
• deep exhalation
• erector spinae