Electromyographic Effects of Postural Correction Exercises in Individuals With Forward Head Posture

Forward head posture (FHD) is a common habitual faulty posture exists in the surrounding that can alter the resting position of the mandible and may affect the masticatory muscle activity.

The aim of this study is to investigate the effect of postural correction on masticatory and cervical muscle activity and mandibular opening in forward-head posture patients.

Materials and Methods:

Cranio-vertebral angle measurement CVA EMG activity of masseter, temporalis, splenius, upper trapezius and SCM BAU - Institutional Review Board (Form H-II) \| BEIRUT ARAB UNIVERSITY

-Electrodes will be placed on the muscle belly parallel to the direction of muscle fibers. The distance between the two electrodes was 2 cm. The subjects will be instructed to complete maximum voluntary contraction (MVC) of clenching the teeth for 3 s and repeating twice. The average of the two trials of MVC will be used for further analysis. The subjects will be seated comfortably in a chair.

• Specific strengthening and stretching exercise (Other): The program consisted of two strengthening (deep cervical flexors and shoulder retractors) and two stretching (cervical extensors and pectoral muscles) exercises based on Harman and Mostafa et al's approach. This exercise program will be repeated 4 times per week for 10 weeks, and each session lasted for 30 minutes.
• General Exercise (Other): The program will consist of regular general postural exercises such as postural awareness exercises as well as general strengthening exercises such as range of motion exercises for the upper quadrant. The program will also be repeated 4 times per week for 10 weeks, with each session lasting 30 minutes

Primary outcomes

• EMG activity [10 weeks]: Electrodes will be placed on the muscle belly parallel to the direction of muscle fibers. The distance between the two electrodes was 2 cm. The subjects will be instructed to complete maximum voluntary contraction (MVC) of clenching the teeth for a period of 3 s and repeated twice. The average of the two trials of MVC will be used for further analysis. The subjects will be seated comfortably in a chair (---cm height).

Secondary outcomes

• craniovertebral angle [10 weeks]: Forward head posture will be assess by the craniovertebral angle, one of the most reliable tool for evaluating the FHP. The examiner takes 2 lateral photographs of the subject in standing position, according to Shaghayegh fard et al. A digital camera will be positioned on a tripod at a distance of 0.8m from the subject at shoulder height. Two land mark will be taken, the spinous process of C7 and the tragus of ear. A horizontal line will be drawn passing through C7 making a right angle with the vertical. Then, the angle between the line connecting C7 spinous process with the tragus of the ear and the horizontal line.

Sex: All, ages: 18 Years to 30 Years

Inclusion Criteria:

* 1\. Participants aged 18- 30 years. 2. Presence of forward head posture, defined as CVA of less than 50° with no symptoms of neck pain \[18, 19\]. 3. No treatment for TMD or cervical symptoms (e.g., medication, physical therapy, or intra-articular injection) within the previous 2 weeks.

Exclusion Criteria:

* 1\. Current or previous diagnosis of temporomandibular disorder (TMD), or the presence of TMD-related signs or symptoms (e.g., joint sounds, restricted mouth opening, or orofacial pain) during screening.

  2\. History of TMJ subluxation or dislocation that could interfere with mouth opening.

  3\. History of recent head or neck trauma. 4. Angle Class II or Class III malocclusion. 5. Postural abnormalities secondary to structural spinal deformities (e.g., scoliosis or kyphosis), rheumatic diseases, or other medical conditions affecting posture.

  6\. Missing posterior teeth, recent orthodontic treatment (within the previous 12 months), or dental restorations that altered occlusion.

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