Osteopathy Journals and Research by Darren Chandler

 

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  1. Supraspinous ligament

    The supraspinous ligament forms part of the posterior ligamentous system of the vertebral column. This extends from C7 to L4 in 73% of adults. Anteriorly, the supraspinous ligament merges with the interspinous ligaments.

    Within the lumbar spine the supraspinous ligament is most easily distinguishable at L2- L3. It then gradually diminishes below this level.

    The supraspinous ligament in the thoracic region is a thin membranous structure. It's only at the thoracolumbar junction does it become better defined.

    Interspinous ligament

    The interspinous ligament blends posteriorly with the supraspinous ligament.

    The interspinous ligaments in the thoracic region is a thin membranous structure. It's absent in the upper thoracic spine being replaced by loose connective tissue between the two multifidus muscles. It’s only at the thoracolumbar junction does the interspinous ligament become better defined.

    Changes in the interspinous ligament have been noted at L5-S1 due to the change in contribution from the aponeurosis of the longissimus thoracis in the lower lumbar spine and the supraspinous ligament being absent at this level. Because of this Heylings (1976) found fibres of the right and left lumbodorsal fascia were thickest at this level and decussated across the mid-line. He also found the most medial tendons of the erector spinae aponeurosis crossed the mid-line to gain attachment to the opposite side of the posterior edge of the L5-S1 spinous process.

    Characteristics of the supraspinous and interspinous ligaments at different levels

    Johnson and Zhang (2002) analysed the supraspinous ligament at different levels.

    Upper thoracic spine (T1–T5)

    The dense connective tissue attaching to the spinous processes in the upper thoracic spine originates mainly from muscles and tendons.

    Tendons of the trapezius and splenius cervicis blend together at the midline creating an impression of a fine ligament running longitudinally over the tips of the spinous processes.

    Dense connective tissue fibers arising from the middle portion of trapezius meet in the midline, decussating prior to attaching to the tips of the T1–T4 spinous processes. They are joined by the tendons of the rhomboid major and splenius cervicis.

    Willard et al (2012) found that although the posterior layer of the thoracolumbar fascia extended up to and fused with the trapezius and rhomboid muscles these muscles are positioned external to it. As such they are enveloped in their own epimysial fascia.

    The deep layer of the thoracolumbar fascia - overlying and connecting with splenius cervicis, longissimus thoracis and iliocostalis - also attaches to the spinous processes.

    The interspinous ligaments are absent throughout the upper thoracic spine. Instead, the interspinous compartment is occupied by a thin layer of loose connective tissue located between the bilateral multifidus muscles.

    Lower thoracic spine (T6–T12)

    At T6 the spinal attachments of the posterior layer of the thoracolumbar fascia becomes evident. This coincides with a marked transition in the midline connective tissue organization and the presence of the decussating fibers of trapezius. 

    This composite of fibers from the posterior layer of the thoracolumbar fascia, dense connective tissue and decussating fibers of trapezius attaches as a single layer of connective tissue directly to the lateral aspect of the T6–T9 spinous processes.

    At T9 the lower portion of trapezius gives rise to a tendinous aponeurosis which spans the lower thoracic and upper lumbar spinous processes.

    T9 also marks the commencement of fiber decussation of the thoracolumbar fascia. These fibers form small fibrous compartments around individual fibers running longitudinally within the lower tendinous portion of trapezius.

    The interspinous ligament commences at T6 as an anterior extension of the thoracolumbar fascia. It forms a single sheet of dense connective tissue bridging between borders of the spinous processes of adjacent vertebrae.

    The posterior layer of the thoracolumbar fascia becomes progressively thicker below T10 and, correspondingly, the interspinous tissue becomes better defined and bilaminar in form.

    Lumbar spine (L1–L5)

    Supraspinous ligament

    The principal connective tissue components of the supraspinous ligament in the Lumbar spine is the mid-line attachments of the:

    • Posterior layer of the thoracolumbar fascia: distinct bands of dense connective tissue fibers from the thoracolumbar fascia cross the midline to merge with the contralateral fibers to contribute to both the supraspinous and intersponous ligament. In the upper lumbar spine the tendonous aponeurosis from the trapezius intertwines with the midline attachments of the thoracolumbar fascia.
    • Longissimus thoracis: with the multifidus contributes to supraspinous ligament formation in the mid and lower lumbar spine.
    • Multifidus: Creze et al (2018) found the multifidus to be strongly attached to the erector spinae aponeurosis close to the midline. The multifidus with the longissimus thoracis contributes to the supraspinous ligament in the mid and lower lumbar spine.

    At L5, the dense connective tissue becomes further modified to create a horizontal T-bar formation as the posterior layer of the thoracocolumbar fascia joins with the common erector spinae aponeurosis to attach onto the L5 spinous process.

    Heylings (1976) found beyond the lower limit of the supraspinous ligament at L5-S1 fibres of the right and left lumbodorsal fascia were thickest and decussated across the mid-line.

    Where the supraspinous ligament was present Heylibngs (1976) found the tendons of the erector spinae aponeurosis gained attachment to the lateral part of the posterior edge of the spinous process. At L5-S1, caudal to the termination of the ligament, the most medial tendons crossed the mid-line to gain attachment to the opposite side of the posterior edge of the L5-S1 spinous processes. More laterally placed tendons at this level remained attached to their own side of these spinous processes.

    The absence of a supraspinous ligament at L5-S1 can be associated with the greater range of flexion in this region.

    Interspinous ligament

    Connective tissue contributions to the interspinous ligament are from:

    • Thoracolumbar fascia: distinct bands of dense connective tissue fibers from the thoracolumbar fascia cross the midline to merge with the contralateral fibers to contribute to both the interspinous and supraspinous ligaments.
    • Longissimus thoracicis aponeurosis.
    • Multifidus tendons.

    The interspinous ligament merges anteriorly with the posterior capsule of the zygoapophyseal joints.

    Sacrum (S1–S5)

    The tendinous origins of the multifidus and erector spinae aponeurosis contribute to the midline dense connective tissue arrangement at this level. Caudal to S3, there is no contribution from the surrounding musculature and the fascia gradually diminishes at the level of the coccyx.

    References

    The thoracolumbar fascia: anatomy, function and clinical considerations (2012). F H Willard, A Vleeming, M D Schuenke, L Danneels and R Schleip

    Regional differences within the human supraspinous and interspinous ligaments: a sheet plastination study (2002). Gillian M. Johnson Ming Zhang

    Supraspinous and interspinous ligaments of the human lumbar spine (1976). D. J. A. HEYLINGS 

    Organization of the fascia and aponeurosis in the lumbar paraspinal compartment (2018). Creze M, Soubeyrand M, Nyangoh Timoh K, Ggey O

  2. Introduction

    Cranial tension is associated with various different conditions from headaches and migraines to temperomandibular joint dysfunction. Myofascial and neurological reflexes can provide an interesting insight into the pathology of these type of disorders. The main clinical points listed in this article are:

    (1) A continuous myofascial chain from the cervical dura running anteriorly over the vertex to the dura of the optic nerve. Myofascially this can produce tightness and an entrapment neuropathy along its course.

    • Suboccipital fascia attaches to spinal dura and galea aponeurotica.
    • Frontalis muscle attaches to the corrugator supercilii and orbicularis oculi.
    • Entrapment of the supratrochlear nerve can occur in the corrugator supercilii.
    • Meningeal tension in the optic nerve from the muscular attachments of Muller's (supratarsal) muscle.

    (2) Myofascial continuity of the cranium.

    Each muscle intern has a seperate origin and insertion. Listed is both the anatomical connections of each muscle and the anatomy of the connecting fascia. Thereby force transmission from one muscle to another can occur across larger distances than any individual muscles origin and insertion.

    (3) Neurological reflexes. 

    Tightening of certain muscles can not only occur from force transmission but also from neurological reflexes. The two neurological reflexes are:

    • Eyelid opening stimulates mechanoreceptors in Muller’s (supratarsal) muscle that causes reflex contraction of the levator palpebrae superioris and frontalis. It also stimulates a response in the sympathetic nervous system.  
    • Tongue position: placing the tongue on the roof of the mouth causes reflex contraction of the temporalis and suprahyoid muscles. It also stimulates a response in decreasing vagal tone.
    • Stretching the suboccipital muscles has been postulated as modulating vagal tone.

    (4) Embryological forces acting through the occipitofrontalis on the cranium and occipitoantlal joint.

    A developmental model has been hypothesised whereby the occipitofrontalis and SMAS are initimately associated with cranial development. They found during late brain growth tension is created in the occipitofrontalis increasing tension in the SMAS. This model describes the occipitofrontalis/SMAS as being a conduit for a brain derived force directing craniofacial development and jaw rotation. This developmental cranial rotation occurs around the occipitoantlal joint.

    Occipitofrontalis & Galea aponeurotica 

    Occipitofrontalis

    Occipitalis: originates from lateral two thirds of the highest nuchal line and mastoid process and extends to the galea aponeurotica.

    Frontalis: originates from the galea aponeurotica and extends to the superficial fascia and the skin above the eyes and nose. Muscular attachments are medial fibers attach to the procerus; intermediate fibers attach to the corrugator supercilii and orbicularis oculi; lateral fibers attach to the orbicularis oculi.

    Kushima et al (2005) found the occipitalis becomes the galea aponeurotica. Galea aponeurotica is attached to the underside of the frontalis.

    Bordoni & Zanier (2014) found the occipitofrontalis continuous posteriorly (via the occipitalis) with the superficial cervical fascia and anteriorly (via the frontalis) with Muller’s (supratarsal) muscle. Muller's (supratarsal) muscle is the smooth muscle fibers of the musculus levator palpebrae.

    The superficial fascia envelopes the occipitalis. The temporoparietal fascia (the temporal part of the superficial fascia) envelopes the frontalis. Kim & Lee (2016) found the temporoparietal muscle continuous with the frontalis.

    Standerwick and Roberts (2009) found the occipitofrontalis and SMAS initimately associated with cranial development. They hypothesised late brain growth creates tension in the occipitofrontalis increasing tension in the SMAS. This model describes the occipitofrontalis/SMAS as being a conduit for a brain derived force directing craniofacial development and jaw rotation. This developmental cranial rotation occurs around the occipitoantlal joint and is responsible for.

    • Enlargement of the airways.
    • Maxillomandibular rotation.
    • Asymmetric separation of the sphenooccipital synchondrosis (SOS): due to the weight of the brain and anteroposterior tension from the occipitofrontalis/SMAS a pivot point is created at the superior aspect of the SOS. This creates a greater separation of the pharyngeal side of the SOS relative to the endocranial aspect.

    The frontalis muscle is attached to the corrugator muscle.

    Galea aponeurotica

    The Galea aponeurotica is a continuation of the occipitalis and is attached

    • Anteriorly: frontalis.
    • Posteriorly the galea aponeurotica transitions to the suboccipital neck fascia by dense fibrous attachments (Dacey et al 2018).
    • Laterally: the galea aponeurotica continues as the temporoparietal fascia (superficial temporal fascia). Both galea aponeurotica and temporoparietal fascia connect the occipitalis and frontalis despite belonging to the deep and superficial aponeurotic systems respectively (Kim & Lee 2016). The Galea also gives rise to the anterior and superior auricular muscles.

    Some authors class the temporoparietalis as part of the galea aponeurotica.

    Deep and superficial musculoaponeurotic system

    Deep musculoaponeurotic system (DMAS)

    The DMAS is composed of the:

    • Occipitalis.
    • Galea aponeurotica.

    Superficial musculoaponeurotic system (SMAS)

    The SMAS is composed of the:

    • Frontalis.
    • Temporoparietal muscle.
    • Temporoparietal fascia.
    • Superficial fascia.

    SMAS becomes continuous with:

    • Mimetic muscles (zygomaticus major, frontalis, periorbital fibers of the orbicularis oculi, corrugator supercilii and buccinator). The SMAS forms a zone of fusion with the buccinator muscle. 
    • Superficial layer of parotid fascia.
    • Mandibulocutaneous ligament: fixes the inferomedial aspect of the SMAS (Holger et al 2008).

    The deep musculoaponeurotic system pulls back the superficial aponeurotic system.

    Mimetic muscles

    Zygomaticus Major

    The Zygomaticus Major originates from the zygoma and inserts on the modiolus. The zygomaticus major interdigitates with the levator anguli oris (Shim et al 2008), buccinator (Shim et al 2008), orbicularis (Spiegal and DeRosa 2005) 

    Buccinator

    The Buccinator originates from the alveolar processes of the maxilla, mandible and temperomandibular joint. It inserts on to the orbicularis oris. It has anatomical connections to the lateral deep slip of the platysma (Hur et al 2015), temporalis (Hur 207), incisivus labii inderioris (Hur et al 2011), zygomaticus major (Shim et al 2008) and parotid duct where it is associated with its function (Kang et al 2006).

    Orbicularis Oculi

    The Orbicularis Oculi occupies the eyelid spreading onto the temporal region and cheek. It attaches to the nasal part of the frontal bone, frontal process of the maxilla and lacrimal bone. It blends with the occipiofrontalis and corrugator muscle. It also blends with the medial palpebral ligament and forms the lateral palpebral raphe. 

    The orbicularis oculi acts as a sphincter of the eyelids (and draws them slightly medially), draws the skin of the forehead, temporal region and cheek towards the medial end of the orbit (causing crow's feet), creates a vertical furrowing above the bridge of the nose and can cause lacrimation.

    Not only can myofascial trigger points create head pain but orbicularis oculi twitching has been associated with cluster headaches (Bagheri et al 2017) and abnormal blink reflexes have been associated with migraine sufferers (Unal et al 2016).

    Metha and Sheshia (1976) found electrical stimulation of the supraorbital nerve (SON) evoked contraction of the orbicularis oculi. Could entrapment of the SON in the corrugator muscle and the fascia of the supraorbital notch cause trigger points in the orbicularis oculi?

    Corrugator Supercilii

    The corrugator suoercilli extends from the medial end of the eyebrow (deep to the occipitofrontalis and orbicularis oculi) to pass laterally and superiorly to the skin above the middle of the supraorbital region. Contraction of the muscle creates a frown. 

    The corrugator supercilli blends with the occipitiofrontalis and orbicularis oculi.

    Janis et al (2013) found the supratrochlear nerve to pierce, and be compressed, by the corrugator muscle causing migraine headaches.

    Superficial fascia & temporoparietal fascia

    • Superficial fascia posteriorly envelopes the occipitalis then continues with the superficial cervical fascia.
    • Superficial fascia in the neck provides a fascial sleeve for the platysma muscle. 
    • Superficial fascia is bound inferiorly by the mandibulocutaneous ligament before ascending over the parotid fascia and zygomatic major to attach with fibrous consistency to the zygomatic arch (Holger et al 2008).
    • The modiolus is formed from a fusion of the zygomaticus major, orbicularis oris, SMAS and buccinator (Holger et al 2008).
    • In the temporal region the superficial fascia becomes the temporoparietal fascia.
    • The temporoparietal fascia is split into the superficial and deep laminae (Beheiry & Abdel-Hamid 2007).
    • The temporoparietal fascia envelopes the frontalis and orbicularis oculi.
    • The inferior temporal septum is formed by fusion of superficial (temporoparietal) and deep temporal fascia. It runs inferiorly along the temporalis originating from the lateral corner of the temporal ligament* extending posteriorly towards the superior crus of the helix (Huang et al 2017).
    • Temporoparietal fascia has tight fibrous fusions with the deep temporal fascia at their insertion into the zygomatic arch but splits from the superficial fascia at this insertion (Holger et al 2008).
    • Temporoparietal fascia has a thin muscle below the temporal line (Tellioglu et al 2000).

    *temporal ligament: between middle and lateral third of eyebrow extending superiorly to the the superficial fascia at the junction of temporoparietal fascia and the galea on the deep surface of the frontalis muscle.

    Cervical spine attachments to the dura and galae aponeurotica

    The cervical spine attaches to the cervical dura and galae aponeurotica by:

    • Myodural bridges from the suboccipital fascia.
    • Meningodural ligaments.

    Myodural bridges from the suboccipital fascia

    Rectus Capitis Posterior Minor (RCPMi)

    The RCPMi extends from C1 (tubercle on posterior arch) to the occiput (medial part of inferior nuchal line & between this and the foramen magnum).

    Rectus Capitus Posterior Major (RCPMa)

    The RCPMa extends from C2 spinous process to the occiput (lateral part of the inferior nuchal line and just below this line).

    Obliqus Capitus Inferior (OCI)

    The OCI extends from the C2 spinous process to the C1 transverse process.

    Fascial extensions from the suboccipital muscles to the dura 

    Superiorly the suboccipital fascia runs, via dense fibrous attachments, into the galea aponeurotica (Dacey et al 2018). This gives a continuous fascial change from the scalp to the epidural space. Scaley et al (2015) found attachments of the suboccipital fascia to the dura:

    RCPMi

    • Deep and lateral fascia of the RCPmi continuous with the PAO membrane and the vascular sheath of the vertebral artery.
    • Posterior Antlo-occipital (PAO) membrane attaches to the posterior border of the foramen magnum. The PAO membrane contains periosteum from the foramen magnum. Anteriorly, the periosteal tissue of the PAO membrane merges with the dura mater at the level just below the atlas. It becomes indistinguishable from the spinal dura at C3.
    • Deep fascia blends with the PAO membrane and is traversed anteroinferiorly to form the atlantooccipital myodural bridge. This bridging structure enters into the epidural space to fuse with the dorsal meningovertebral ligament of C1 sharing a common insertion site on the posterior surface of the dura mater.

    RCPMa & OCI

    • The epimysium of the RCPma and OCI attaches to (1) in part the C2 lamina (2) but mainly they combined to form fibrous bands that traverses the atlantoaxial interspace.
    • These fibrous bands passed between two thin strips of the ligamentum flavum.
    • Once through the ligamentum flavum the fascial bands merges within the epidural space to become the atlantoaxial myodural bridge.
    • C2 spinal nerve pierces the antloaxial myodural bridge.
    •  Atlantoaxial myodural bridge blends with (1) dorsal meningovertebral ligament of C2. (2) A structure extending from the inferior pole of the posterior arch of C1 and ligamentum flavum of C1/C2 to the antloaxial myodural bridge.
    • All these soft tissue structures that inserts into the dura were easily separable but maintained a common dural insertion point.

    Janis et al (2010) found a tight fascial band surrounding the belly of the obliquus capitis inferior muscle near the spinous process that is potentially capable of compressing the greater occipital nerve.

    Meningodural ligaments

    Meningodural ligaments are connective tissue bands running mainly from the ligamentum nuchae but also the laminae to the dura. Most commonly from C5 up with the strongest attachments being at C2 (Shi et al 2014)

    Soft tissue tightness in the muscles associated with the ligamentum nuchae (upper trapezius, rhomboideus minor, serratus posterior superior, and splenius capitis (Nan Zhen et al 2014)) has been linked to headaches.

    Reflex tightening of the SMAS

    Reflex muscle tightness in the SMAS can occur via myofascial continuity and neurological reflexes. The two facial structures involved in these reflexes are the:

    • Eye lid position.
    • Tongue position.
    • Suboccipital tightness.

    Eye lid position

    Mechanoreceptors in Muller’s (supratarsal) muscle is innervated by the trigeminal nerve that terminates in the mesencephalon. Eyelid opening stretches mechanoreceptors in the Müller (supratarsal) muscle to activate the proprioceptive fibers supplied by the trigeminal mesencephalic nucleus. This proprioception induces reflex contractions of the levator palpebrae superioris and frontalis muscles to sustain eyelid and eyebrow positions against gravity (Matsuo et al 2015) and the occipitofrontalis (Bordoni & Zanier, 2014).

    There is a direct myofascial link whereby tension in the posterior superficial cervical fascia pulls on and stimulates mechanoreceptors in Muller’s (supratarsal) muscle via the occipitofontalis and levator palpebrae superioris (Bordoni & Zanier, 2014). Muller's (supratarsal) muscle is the smooth muscle fibers of the levator palpebrae superioris attached to the medial and lateral rectus muscle pulley (Kakizaki et al 2010).

    This stimulation of mechanoreceptors in Muller’s muscle not only exerts a somatic neurological reflex in tightening muscles in the head but also an autonomic reflex via the locus coeruleus.

    Based on these neural connections day to day activities of the eyes creates varying states of arousal and vigilance to facilitate our everyday activities.

    Stimulating the mechanoreceptors in Muller's (supratarsal) muscle stimulates the locus coeruleus creating arousal just as not stimulating them can create sedation. For example opening and rubbing the eyes will stimulate mechanoreceptors in Muller's (supratarsal) muscle to evoke vigilance such as when opening our eyes on waking, rubbing our eyes to stay awake or evoking memory retrieval by an upward gaze. Closing our eyes or evoking a downward gaze can decrease stimulation in the mechanoreceptors in Muller’s (supratarsal) muscle to help with sedation of the locus coeruleus such as when meditating or sleeping (Matsuo et al 2015).

    The Locus coeruleus is not just associated with day to day vigalence but in pain modulation via locus coeruleus-noradrenergic neuromodulatory system. When dysfunctional it has been associated with a range of chronic pain conditions such as temperomadibular dysfunction (TMD) associated with dysfunction of the noradrendergic arousal system (Monaco et al 2015).

    The potential for stimulation of the locus coeruleus via trigeminal afferents is reflected in the sympathetically mediated sweat response in response to prolonged upward gaze (Matsuo et al 2015) a phenomena also associated with trigeminal autonomic cephalagia (Costa et al 2015).

    To extend the myofascial chain from the superficial cervical fascia to the Levator Palpebrae Superioris further the Levator Palpebrae Superioris and rectus superior muscle is connected with Tenon’s capsule, where the eyeball is located; particularly, they share extraocular muscles; Tenon’s capsule surrounds the optic nerve where it terminates in the eye, blending with the meningeal tissue. Could it be that tension in the fascial area in the upper cervical spine affects the movement of the eyeball, altering the visual field and posture, or causing dysfunction related to the fascial traction on the optic nerve, with resultant alteration in the ocular reflexes? (Bordoni Zanier 2014).

    Tongue position

    Schmidt et al (2009) found placing the tongue on the roof of the mouth:

    • Increased muscle activity in the temporalis and suprahyoid muscles.
    • Reduction in cardiac vagal tone.

    Because there is evidence that even small increases in muscle activity for extended periods can result in the development of pain and dysfunction, the importance of allowing the tongue to rest as frequently as possible seems self-evident.

    Suboccipital tightness

    The suboccipital fascia has a

    • Myofascial continuity with cervical dura posteriorly (Scaley et al 2015) coursing anteriorly around the head to Tenon's capsule where it blends with meningeal tissue of the optic nerve in the eye (Bordoni & Zanier, 2014).
    • Standerwick and Roberts (2009) found late brain growth creates tension in the occipitofrontalis increasing tension in the SMAS. This tension directs craniofacial development and jaw rotation that occurs around the occipitoantlal joint.
    • Suboccipital release has been hypothesised as affecting vagal tone (Kwan et al 2013 & Giles et al 2008). Could this work in concert with mechanisms affected by tongue and eyelid position?

    References

    The occipitofrontalis muscle is composed of two physiologically and anatomically different muscles separately affecting the positions of the eyebrow and hairline. (2005). Kushima H, Matsuo K, Yuzuriha S, Kitazawa T, Moriizumi T

    Clinical and symptomatological reflections: the fascial system (2014). Bruno Bordoni and Emiliano Zanier

    A Case Report of the Angiosarcoma Involving Epicranial Muscle and Fascia: Is the Occipitofrontalis Muscle Composed of Two Different Muscles? (2016). Ho Kyun Kim, and Hui Joong Lee

    Surgical Anatomy of the Face: Implications for Modern Face-lift Techniques (2008). Holger G. Gassner, Amir Rafii, Alison Young, Murakami C, Moe KS, Larrabee WF Jr.

    Shunt scissors: technical note (2018). Dacey RG, Flouty OE, Grady MS, Howard MA, Mayberg MR.

    An anatomical study of the temporal fascia and related temporal pads of fat. (2007). Beheiry EE, Abdel-Hamid FA

    The Anatomy of the Greater Occipital Nerve: Part II. Compression Point Topography (2010). Jeffrey E. Janis, Daniel A. Hatef, Ivica Ducic, Edward M. Reece, Adam H. Hamawy, Stephen Becker, Bahman Guyuron. 

    Anatomical Study of Temporal Fat Compartments and its Clinical Application for Temporal Fat Grafting (2017). Ru-Lin Huang, Yun Xie, Wenjin Wang, Tanja Herrler, Jia Zhou, Peijuan Zhao, Lee LQ Pu and Qingfeng Li,

    Temporoparietal fascia: an anatomic and histologic reinvestigation with new potential clinical applications (2000). TellioÄŸlu AT, Tekdemir I, Erdemli EA, Tüccar E, Ulusoy G.

    Investigation of meningomyovertebral structures within the upper cervical epidural space: A sheet plastination study with clinical implications (2015). Scali F, Pontell ME, Nash LG, Enix DE.

    An anatomical study of the buccinator muscle fibres that extend to the terminal portion of the parotid duct, and their functional roles in salivary secretion. Hyo-Chang KangHyun-Ho KwakKyung-Seok HuKwan-Hyun YounGuang-Chun JinChristian Fontaine, and Hee-Jin Kim

    Blending of the lateral deep slip of the platysma muscle into the buccinator muscle. (2015) Hur MSBae JHKim HJLee HBLee KS.

    Inferior bundle (fourth band) of the buccinator and the incisivus labii inferioris muscle. (2011). Hur MSHu KSKwak HHLee KSKim HJ.

    Anatomical connections between the buccinator and the tendons of the temporalis. (2017). Hur MS

    An anatomical study of the insertion of the zygomaticus major muscle in humans focused on the muscle arrangement at the corner of the mouth. (2008). Shim KSHu KSKwak HHYoun KHKoh KSFontaine CKim HJ

    The anatomical relationship between the orbicularis oculi muscle and the levator labii superioris and zygomaticus muscle complexes. (2005). Spiegel JH, DeRosa J.

    The Aponeurotic Tension Model of Craniofacial Growth in Man (2009). Richard G Standerwick and W. Eugene Roberts

    Effects of tongue position on mandibular muscle activity and heart rate function (2009) John E. Schmidt, Charles R. Carlson, Andrew R. Usery, Alexandre S. Quevedo, Rochester MN, Lexington and Winston-Salem NC

    Eyelid Opening with Trigeminal Proprioceptive Activation Regulates a Brainstem Arousal Mechanism (2015).Kiyoshi Matsuo, Ryokuya Ban, Yuki Hama, and Shunsuke Yuzuriha

    Clinical and symptomatological reflections: the fascial system (2014). Bruno Bordoni and Emiliano Zanier

    The Neuropharmacology of Cluster Headache and other Trigeminal Autonomic Cephalalgias (2015). Alfredo Costa, Fabio Antonaci, Matteo Cotta Ramusino, and Giuseppe Nappi

    Using suboccipital release to control singultus: a unique, safe, and effective treatment (2013). Kwan CSWorrilow CCKovelman IKuklinski JM.

    Suboccipital Decompression Enhances Heart Rate Variability Indices of Cardiac Control in Healthy Subjects (2008). Paul D. GilesKendi L. HenselChristina F. Pacchia, and Michael L. Smith

    The morphology and clinical significance of the dorsal meningovertebra ligaments in the cervical epidural space (2014). Shi B, Zheng X, Min S, Zhou Z, Ding Z, Jin A.

    Definition of the To Be Named Ligament and Vertebrodural Ligamentand Their Possible Effects on the Circulation of CSF (2014). Nan Zheng, Xiao-Ying Yuan, Yun-Fei Li, Yan-Yan Chi, Hai-Bin Gao, Xin Zhao, Sheng-Bo Yu, Hong-Jin Sui, and John Sharkey.

    Cluster Headache Associated with Secondary Unilateral Blepharospasm: A Case Report and Review of the Literature (2017). Abbas Bagheri, Minoo Mohammadi, Ghader Harooni, Keyvan Khosravifard, Mohadeseh Feizi and Shahin Yazdani

    Blink reflex in migraine headache (2016). Zeynep Unal, Fusun Mayda Domac, Ece Boylu, Abdulkadir Kocer, Tulin Tanridag, and Onder Us

    Anatomy of the supratrochlear nerve: implications for the surgical treatment of migraine headaches (2013). Janis JE, Hatef DA, Hagan R, Schaub T, Liu JH, Thakar H, Bolden KM, Heller JB, Kurkjian TJ.

    Orbicularis oculi reflex in brain death (1976). A J Mehta, S S Seshia

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