Upper cervical spine mobility plays a crucial role in temporomandibular joint (TMJ) function. This observational study investigates the relationship between upper cervical spine mobility and TMJ range of motion in patients diagnosed with temporomandibular disorders (TMD). Cervical hypomobility may restrict mandibular movement and contribute to TMJ dysfunction through shared biomechanical and neuromuscular mechanisms.

Temporomandibular disorders (TMD) are multifactorial conditions involving the temporomandibular joint, masticatory muscles, or both. Prior research indicates a strong association between TMD and cervical spine dysfunction, with patients frequently exhibiting neck pain, reduced cervical motion, and muscular tenderness.

This study explores how upper cervical mobility (flexion, extension, and rotation) correlates with TMJ range of motion (mouth opening, lateral excursion, and protrusion). The aim is to identify whether cervical spine hypomobility contributes to restricted jaw movement in TMD patients.

A total of 50 participants with TMD will undergo standardized clinical measurements of cervical mobility using a CROM device and TMJ motion using a ruler or caliper. Pearson or Spearman correlation coefficients will be applied to evaluate the association between cervical and TMJ movement parameters.

Inclusion Criteria:

• Medically stable individuals who consent to participate in the study.
• Age between 18 and 50 years.
• Both male and female participants.
• Patients diagnosed with temporomandibular joint (TMJ) dysfunction for at least three months.

Exclusion Criteria:

• Presence of systemic diseases.
• Body mass index (BMI) greater than 30 kg/m².
• Pregnancy.
• Recent physical therapy for cervical spine disorders, headaches, or temporomandibular dysfunction.
• Cervical radiculopathy or other neurological disorders.
• History of trauma or major psychological problems.
• Generalized joint hypermobility.
• Down syndrome.

Participants will be adult patients (both male and female) aged 18 to 50 years who have been clinically diagnosed with temporomandibular joint (TMJ) dysfunction for more than three months. All participants will be recruited from the outpatient clinic of the Faculty of Physical Therapy, Deraya University, Minya, Egypt. Eligible participants will be medically stable and free from systemic or neurological disorders that could affect cervical or temporomandibular mobility.