What are the effects of mandibular (lower jaw) retraction on cervical (neck) musculature?

From the Guidelines

Lower jaw retraction can have a significant impact on neck musculature, leading to increased tension and strain in key muscle groups, and treatment should prioritize a multidisciplinary approach to address the underlying jaw position and muscle imbalance. When the mandible is habitually positioned posteriorly, the suprahyoid muscles (including digastric, mylohyoid, and geniohyoid) become chronically elongated and strained as they work to maintain airway patency 1. Simultaneously, the suboccipital muscles and upper trapezius often develop compensatory tension as the head position shifts forward to maintain airway space. This altered posture creates a domino effect, with the sternocleidomastoid and scalene muscles becoming overactive and shortened.

The effects of lower jaw retraction on neck musculature can be understood by examining the biological mechanism, which involves proprioceptive feedback loops where altered jaw position disrupts normal neuromuscular patterns in the craniocervical region 1. Treatment typically requires a multidisciplinary approach including physical therapy focused on neck muscle rebalancing, myofunctional therapy to improve tongue position and function, and potentially orthodontic or prosthodontic interventions to address the underlying jaw position. Patients often benefit from specific exercises targeting the deep neck flexors and stretches for the suboccipital region to counteract these muscular adaptations.

Some key points to consider in the treatment of lower jaw retraction and its impact on neck musculature include:

• The importance of a multidisciplinary approach to address the underlying jaw position and muscle imbalance
• The use of physical therapy to focus on neck muscle rebalancing and myofunctional therapy to improve tongue position and function
• The potential need for orthodontic or prosthodontic interventions to address the underlying jaw position
• The benefits of specific exercises targeting the deep neck flexors and stretches for the suboccipital region to counteract muscular adaptations. According to the most recent study 1, mandibular advancement devices (MAD) can be an effective treatment option for patients with mild to moderate OSA, and can help to improve nocturnal oxygenation and reduce daytime sleepiness.

From the Research

Effects of Lower Jaw Retraction on Neck Musculature

• The effects of lower jaw retraction on neck musculature have been studied in various contexts, including chronic non-specific neck pain and lifting exercises 2, 3.
• A study on the effects of integrating jaw opening and closing movements with active neck exercises found that the experimental group showed better improvements in reducing pain and disability, improving neck muscles endurance, and normalizing neck proprioception compared to the control group 2.
• Another study examined the effects of neck posture during lifting and found that a retracted neck posture resulted in less lumbar spine flexion and increased lumbar erector spinae, external oblique, and sternocleidomastoid activity 3.
• The effects of corrective exercises on posture, pain, and muscle activation of patients with chronic neck pain have also been studied, with significant alterations observed in cervical angle, shoulder angle, neck pain and disability, and movement control 4.
• A trial into the effects of repeated neck retractions in normal subjects found that repeated neck retraction movements resulted in a statistically significant change in the resting neck posture, which could be beneficial for patients attempting to maintain a more retracted neck position for pain relief 5.
• A comparison of the effects of craniocervical flexion exercise and isometric neck exercise in patients with chronic neck pain found that both groups showed improved pain, neck disability index, endurance of the cervical flexor muscles, and active cervical range of motion, with significantly greater improvements following craniocervical flexion exercise 6.

Key Findings

• Lower jaw retraction can have a positive effect on neck musculature, particularly in reducing pain and disability, and improving neck muscles endurance 2, 3.
• Corrective exercises, including neck retraction movements, can be beneficial for patients with chronic neck pain, resulting in significant alterations in cervical angle, shoulder angle, and neck pain and disability 4, 5.
• Craniocervical flexion exercise has been found to be more effective than isometric neck exercise in improving pain, cervical lordosis, and neck-related function disorders among patients with non-specific chronic neck pain 6.

Muscle Activation and Posture

• The activation of neck muscles, including the sternocleidomastoid and cervical erector spinae, has been found to be affected by lower jaw retraction and corrective exercises 3, 4.
• The posture of the neck and head has been found to have a significant influence on the posture of the lower spine region during lifting, with a retracted neck posture resulting in less lumbar spine flexion and increased lumbar erector spinae activity 3.