Cervical Stabilization in Individuals With Obstructive Sleep Apnea

Sleep quality will be assessed twice through the Pittsburgh sleep quality index (PSQI), composed of nine self-administered questions, with scores scattered on a scale of zero to three. The sum of the responses provided by the overall score, which ranges from zero to 21, where the higher the score, the worse the quality of sleep.

The craniocervical dysfunction index evaluates the cervical function and is composed of five items: amplitude of cervical movements, presence of pain to cervical movement, presence of noises and blockages in the cervical joints, pain on the palpation of the cervical muscles and craniocervical posture. For each evaluated item three scores are possible (0, 1 or 5) and the volunteers can be classified into four categories according to the severity of the dysfunction: no dysfunction (0 points), mild dysfunction (1 to 4 points), moderate dysfunction (5 to 9 points) and severe (10 to 25 points)

The pressure pain threshold will be evaluated by means of an analog algometer (Wagner Instruments). This appliance has a 1 cm rubber ferrule attached at its end, which will be positioned perpendicular to the muscular surface.

For this, the participants will be seated in a chair, with the trunk upright, back fully supported, feet resting on the ground and hands resting on the lower limbs. The pressure pain threshold will be bilaterally assessed in the masseter (upper, middle and lower) and temporal (anterior, middle and posterior) muscles, submandibular region, posterior mandibular region, sternocleidomastoid, upper trapezius and suboccipital muscles. All points will be gradually pressed up to the intensity that the participant reports any pain intensity, this value being visualized on the equipment and recorded as pain threshold at pressure.

The instrument that will be used to evaluate presence of TMD is Diagnostic criteria in research for temporomandibular disorders (RDC / TMD), which is divided in 2 axis: in Axis I allows the measurement of TMD signs and symptoms (physical evaluation) and in Axis II it evaluates the psychological and psychosocial factors (questionnaire).

To measure TMD severity the Temporomandibular Index (TMI) is used, this result is obtained from RDC/TMD data from Axis I. Result is a qualification among light (0 to 0,3), moderate (0,3 a 0,6) or severe (0,6 to1) TMD according to TMI calculated.

The posture of the head and cervical spine will be evaluated by means of digital photography, with posterior analysis in the Postural Evaluation Software (SAPo v 0.68®). The anatomical points of the tragus, spinous process of the seventh cervical vertebra and orbicular commissure will be demarcated with Styrofoam balls in the participant's body.

The evaluation of muscle strength of cervical flexors and extensors will be performed using a Microfet 2 manual dynamometer (Hoggan Health industries, West Jordan, USA). For the assessment of cervical flexors, the participant will be positioned in the supine position, knees extended, head and neck in neutral position. The manual dynamometer will be positioned in the midline of the frontal bone and will be held by the evaluator, while the participant performs the maximum voluntary isometric contraction of the cervical flexors.

In order to evaluate the strength of the cervical extensors the participant will be positioned in the prone position, with the upper limbs next to the trunk. The manual dynamometer will be positioned in the line of the occipital protuberance.

Data from three repetitions will be obtained for flexion and cervical extension, each repetition lasts 5 seconds and the rest period between the repetitions is 60 seconds.