Exploring the neurophysiological effects of chiropractic care in infants: a feasibility study

Participants will be placed in the intervention or control group using alternating allocation (eg. first participant will be in intervention, second in control, third in intervention etc.). The intervention consists of a single 30-minute session of chiropractic care. Chiropractic adjustments (treatment) is given with the infant lying supine or prone (depending on segment and type of adjustment) on a special pillow with the centre hollowed out for comfort and safety. If the infant is distressed, then the adjustment can be given whilst the infant is held by the caregiver. The intervention will consist of gentle chiropractic adjustments to dysfunctional spinal segments and cranial sutures. The intervention will be provided by a chiropractor with significant training and experience (10+ years) in paediatric chiropractic care. The intervention will be delivered in a pragmatic approach based on the assessment of the chiropractor, rather than a pre-prescribed treatment, as this reflects standard practice and ensures that the spine and cranial dysfunctions are addressed on an individual basis. Spinal adjustments involve placing a light fingertip contact on the restricted side of the affected segment and applying gentle pressure, which is held for several seconds until the therapist feels a change in the muscle tone. Cranial adjustments are given by placing light fingertip contacts along the restricted cranial sutures and applying gentle pressure with small strokes into the area. All spinal and cranial adjustments provided will be documented by the chiropractor. Immediately prior to the intervention EEG will be recorded using a 14-channel disposable cap (Greentek Flex-Cap). This elastic cap allows for comfortable, high-quality signal EEG recording with a one size fits most newborn sized cap. EEG preparation will include placing the cap onto the infant’s head and securing the Velcro chin strap. Conductive gel will be injected into each electrode by a syringe with a blunt needle, and then each electrode will be gently pressed down to ensure the gel reaches the scalp. This is needed to reduce the impendence and ensure excellent quality EEG signals. The impedance of the electrodes will be kept below 10kOhms. The EEG preparation will take approximately 10 minutes. Following the preparation, infants will be swaddled and placed in a supine position on a special pillow with the centre hollowed out for comfort and safety; the caregiver will be seated next to the infant to keep the infant calm. Infants will be in a quiet but awake state during recording .The EEG signals will be checked by an EEG specialist to ensure clear, artifact-free signal conduction. Once clear signals have been confirmed, resting-state EEG will be recorded from infants for 5 minutes. The EEG cap will then be removed and the intervention. The cap must be removed because it involves cranial adjustments that cannot be performed with the cap in place. Immediately following the intervention the EEG cap will be placed back on the infant, signals checked, and if clear another 5 minutes of recording will take place with the infant in a quiet, but awake state. At the same time as the EEG recording, heart rate variability (HRV) will also be recorded via a three- lead ECG. ECG electrodes will be placed on the infants chest in the following positions: right arm (RA) electrode will be placed under the right clavicle at the second intercostal space at the mid-clavicular line; the left arm (LA) electrode will be placed under the left clavicle at the second intercostal space at the mid-clavicular line; the left leg (LL) electrode will be placed on the left side below the pectoral muscles on the lower rib cage. The ECG leads will then be connected to the electrodes and the amplifier for recording. Recording will take place immediately before and after the intervention or control. Following the completion of the EEG and ECG recordings, the data will be saved and briefly checked by an EEG specialist to ensure adequate recording has taken place.