Clinical Research Directory

Pericranial tenderness will be assessed using the Total Tenderness Score, a standardized clinical examination based on manual palpation of pericranial and cervical muscles. Bilateral palpation will be performed on eight pairs of muscle bodies and insertions including the masseter, temporalis, frontal muscle, coronoid process, upper trapezius, sternocleidomastoid, suboccipital muscles, and mastoid process. Palpation will be applied with approximately 1 kg of pressure using the second and third fingertips rotated for four to five seconds. Participant responses will be rated using a four point scale ranging from 0 (no tenderness) to 3 (severe tenderness with withdrawal or pronounced facial reaction). The sum of all responses will generate the Total Tenderness Score, with a maximum possible score of 48. This assessment is commonly used to quantify pericranial muscle tenderness in patients with headache and temporomandibular disorders.

Pressure pain thresholds will be assessed using a handheld digital algometer equipped with a 1 cm² probe. The probe will be positioned perpendicular to the skin at predefined extra trigeminal anatomical sites including the tibialis anterior muscle, the radial carpal extensor region at the dorsal wrist joint line, and the interspinous space between L5 and S1. Pressure will be progressively applied at a constant rate following visual guidance provided by the device interface. Participants will be instructed to indicate the moment when the sensation changes from pressure to pain. Three measurements will be obtained at each anatomical site with a resting interval between assessments. The mean value of the repeated measurements will be recorded and used to quantify generalized mechanical pain sensitivity.

Pain related temporomandibular disorders will be assessed using the standardized Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) clinical protocol. The examination includes structured assessment of temporomandibular joint pain, masticatory muscle pain, mandibular movement, joint sounds, and pain during functional movements or palpation. Based on the DC/TMD diagnostic algorithms, participants will be classified into pain related temporomandibular disorder categories including arthralgia, myalgia, combined myalgia and arthralgia, or headache attributed to temporomandibular disorder. The examination will be performed by trained clinicians following the validated DC/TMD protocol.

Participants will complete standardized self-reported questionnaires to assess pain related symptoms and associated health conditions. These will include the Central Sensitization Inventory to evaluate symptoms associated with central sensitization, the Brief Pain Inventory Short Form to assess pain intensity and pain related interference with daily activities, and a body pain drawing to document the distribution of pain. Additional questions will collect information on the presence and duration of physician-diagnosed chronic overlapping pain conditions. The questionnaires will be administered through a secure electronic data collection platform prior to or during the clinical assessment.

Cervical function will be assessed using the NeckCare system, a wearable sensor-based platform designed to measure cervical spine kinematics and sensorimotor control. The system uses a lightweight head-mounted sensor connected to a computer interface that records cervical movement in real time. Active cervical range of motion will be measured for flexion, extension, right and left rotation, and right and left lateral flexion. Cervical proprioception will be evaluated using the Joint Position Error test, in which participants attempt to reposition the head to a neutral position without visual feedback after performing active cervical movements. Sensorimotor control will also be assessed using the Butterfly Test, which requires participants to follow a moving visual target with head movements while the system quantifies movement accuracy, coordination, and smoothness.

Participants will undergo a standardized multimodal clinical assessment designed to characterize pain sensitivity and related clinical variables. The assessment will include evaluation of pericranial muscle tenderness using the Total Tenderness Score, measurement of extra trigeminal pressure pain thresholds with digital algometry, and clinical examination for temporomandibular disorders using the Diagnostic Criteria for Temporomandibular Disorders protocol. Participants will also complete validated patient reported outcome measures assessing central sensitization symptoms, pain intensity, pain related interference, and distribution of pain. In addition, cervical spine function will be evaluated through objective measurement of cervical range of motion, proprioception, sensorimotor control, and cervical flexor muscle strength and endurance using wearable sensor technology and digital dynamometry. This integrated evaluation provides a comprehensive characterization of local and generaliz