Anatomy, Head and Neck, Supratrochlear

Article Author:
Patrick Zito
Article Editor:
Pradip Chauhan
Updated:
5/4/2020 5:29:09 PM
PubMed Link:
Anatomy, Head and Neck, Supratrochlear

Introduction

An anatomical structure resembling a pully is known as a trochlea; "trochlea" is a Greek word, the English meaning of the trochlea is pully.

In the human body, many pulley-like structures are known as a trochlea; for example, the medial part of an articular area at the lower end of the humerus is called the trochlea. A ligamentous structure attached to the hyoid bone acts as pully for the digastric muscle.[1] The superior surface of the talus is also known as the trochlear surface.[2]

In the ocular orbit, trochlea is a fibrous cartilaginous pully like structure on the nasal aspect of the frontal bone through which superior oblique muscle passes.[3][4] 

Structure and Function

The trochlea is a spine-like structure present at the medial angle of the orbit; the trochlea is a part of the orbital surface of the frontal bone. The orbital part of the frontal bone forms roof of the orbit and ethmoidal sinus.[4][5]

The supratrochlear nerve and tendon of the superior oblique muscle pass through the trochlea, while the supratrochlear artery passes posterior to the trochlea.[4] 

Embryology

The frontal bone develops from neural crest cells controlled by Msx1 and Dlx5 genes; during development, the frontal bone passes under membranous ossification.[6][7]

The development of trochlea is not clear; recent studies describe the trochlea developing with superior oblique muscle tendon. It moves with the tendon and then develops as the fibrocartilaginous pully at 12 weeks of gestational age.[8][9][4] One hypothesis describes the trochlea potentially originating from the common anlage with the sclera.[8]

The supratrochlear nerve originates from the neural crest cell.[10][11] 

Blood Supply and Lymphatics

Supratrochlear artery (Image 2): The supratrochlear artery is a terminal branch of the ophthalmic artery (intracranial branch of the internal carotid artery).

Course: After emerging from the ophthalmic artery, the supratrochlear artery crosses trochlea along with the supratrochlear nerve; then, it crosses the supraorbital margin, pierces the orbital septum and enters the forehead. In the forehead, it runs between corrugator supercilii, orbicularis oculi, and the frontalis muscle.[12][13][14][15][3] Above the level of the mid-forehead, it pierces frontalis muscle and becomes subcutaneous.[16][17][12]

Supratrochlear artery anastomoses with the branches of the supraorbital and superficial temporal artery, both ipsilateral and contralateral, to form a rich vascular network.[16][17][12]

Branches and area of distribution: the bony branches of the supratrochlear artery supply the periosteum of the supraorbital rim and glabella. Muscular branches supply the muscle of the upper eyelid, corrugator supercilii, frontalis, and procerus muscle. Cutaneous branches supply the glabellar skin and skin of the medial forehead.[16][17][12][13][14][15][3]

A study by Kleintjes describes nine branches of the supratrochlear artery:(i) the medial communicating branch that communicates with the contralateral artery, (ii) the lateral communicating branch that communicates with the supraorbital artery, (iii) Superior palpebral artery supplying the upper eyelid, (iv) branch to the brow, (v) periosteal branch, (vi) cutaneous branch supplying the skin of the glabella and median forehead, (vii) oblique branch, (viii) a vertical branch, (ix) medial and lateral vertical branches.[15][12]

Supratrochlear vein: The supratrochlear vein drain the medial forehead, glabellar complex, and periosteum of the medial part of the supraorbital margin. It divides into two branches; one branch accompanies the supratrochlear artery, another branch unites with the supraorbital vein, and forms the angular vein.[18][14][19]

Nerves

Supratrochlear nerve: The supratrochlear nerve is a branch of the frontal nerve (branch of the ophthalmic division of the trigeminal nerve).

Course: The supratrochlear nerve passes forward relative to levator palpebrae superioris muscle; turns medially above the trochlea. Here it gives a descending branch to the infratrochlear nerve then enters into the forehead through the frontal notch.[20][21][22][23][24][25][14] Once it exits the foramen, the supratrochlear nerve ascends to the forehead and runs close to the frontalis and corrugator supercilia muscles. At this junction, it divides and supplies the lower skin of the forehead next to the midline, conjunctiva, and the skin of the upper eyelid.[14][26][27][20][22]

Branches and area of distribution: The descending branch of the supratrochlear nerve combine with the infratrochlear branch of the nasociliary nerve.[20][21][22] The supratrochlear nerve gives sensory branches to the cornea, conjunctiva, the skin of the upper eyelid, the bridge of the nose, and the skin of the forehead. The supratrochlear nerve carries touch, pain, and temperature sensation from the area of the distribution.[23][24][25][14][10]

Muscles

The superior oblique muscle attaches to the trochlea, where it changes direction to insert on the eyeball. The origin of the superior oblique muscle from the body of the sphenoid near the margin of the optic canal. It changes direction at the trochlea. Then it runs backward and laterally on the superior surface of the eyeball behind the equator.[4][28]

The action of the superior oblique muscle is intorsion, depression, and abduction of the eyeball.[4]

Physiologic Variants

Robert et al. reported that in 36% of cases, the supratrochlear nerve originated from the frontal nerve at the distal half of the orbit, while in 64% of cases, the supratrochlear nerve origin was from the frontal nerve at the proximal half the orbit.[10] The supratrochlear nerve may exit the orbit through the supraorbital notch/foramen along with the supraorbital nerve.[10][29][30][31] The supratrochlear nerve gives branches at 4 to 10 mm distance from the supraorbital rim; sometimes, it does not divide.[31] In some cases, the supratrochlear nerve was absent, while in some instances an accessory supratrochlear nerve is also present.[31][32]

The supratrochlear artery branches from the ophthalmic artery in 85 to 90% cases, while in 10 to 15% of cases, the supratrochlear artery and the supraorbital artery emerge as a single branch from the ophthalmic artery and then divide into supratrochlear and supraorbital arteries.[33][12] In some cases, the supratrochlear artery is absent, where the paracentral artery may replace it.[15][12] The branching pattern of the supratrochlear artery also has variation; in most cases, it divides into superficial and deep branches, whereas in some cases, the deep branch was not present. The supratrochlear artery also shows a variation in the number of branches.[12][33][15]

Surgical Considerations

For the midline forehead flap, the supratrochlear artery and its branches play a critical role along with the supraorbital artery. The supratrochlear artery forms anastomoses with the contralateral supratrochlear artery, the supraorbital artery, and the superficial temporal artery. Because of the rich vascularization, the skin supplied by the supratrochlear artery is often used as a skin graft/pedicle to repair the defect at the bridge of the nose or upper facial defect also.[15][34][35]

Fracture of the roof of the orbit may lead to injury of the trochlea, which complicates as a compromised action of the superior oblique muscle; in severe injury, the position of the eyeball is also affected, leading to exophthalmos or enophthalmos.[36][37][38][39][40]

The supratrochlear nerve block is performed in combination with a supraorbital nerve block as regional anesthesia, local infiltration, or field anesthesia for procedures such as repairing of scalp lacerations, craniotomies, and scalp lesion excision.[41][42][43] Between 2 and 3 ml of 1% lidocaine is injected 1 cm medial to the supraorbital foramen to block the supratrochlear nerve.[41]

Clinical Significance

The supratrochlear nerve may become entrapped at the supraorbital margin, supraorbital foramen, or within the corrugator supercilii muscle; the condition may present as chronic frontal migraine. The nerve is relieved by endoscopically or by injecting the botulinum toxin to relieve the migraine.[22][44][45][46]

Embolia Cutis Medicamentosa (ECS) is a phenomenon following an intra-arterial filler injection. The drug or fluid may accidentally enter the supratrochlear or supraorbital artery while injecting the glabellar skin. Injecting fluid in the supratrochlear artery has been found as one of the causes of embolism of the ophthalmic artery and central artery of the retina; embolism of the central artery of the retina may lead to blindness.[47][48][49][50][51]



  • Contributed Illustration by Bryan Parker
    (Move Mouse on Image to Enlarge)
    • Image 216 Not availableImage 216 Not available
      Contributed Illustration by Bryan Parker

  • Contributed by Patrick J. Lynch, medical illustrator, Creative Commons Attribution 2.5 License 2006.
    (Move Mouse on Image to Enlarge)
    • Image 6751 Not availableImage 6751 Not available
      Contributed by Patrick J. Lynch, medical illustrator, Creative Commons Attribution 2.5 License 2006.

  • Contributed by Dr. Pradip Chauhan, MS Anatomy
    (Move Mouse on Image to Enlarge)
    • Image 13848 Not availableImage 13848 Not available
      Contributed by Dr. Pradip Chauhan, MS Anatomy

  • Contributed by Dr. Pradip Chauhan, MS Anatomy
    (Move Mouse on Image to Enlarge)
    • Image 13849 Not availableImage 13849 Not available
      Contributed by Dr. Pradip Chauhan, MS Anatomy

  • Contributee by Dr. Pradip Chauhan, MS Anatomy
    (Move Mouse on Image to Enlarge)
    • Image 13851 Not availableImage 13851 Not available
      Contributee by Dr. Pradip Chauhan, MS Anatomy

References

[1] Gordon A,Alsayouri K, Anatomy, Shoulder and Upper Limb, Axilla 2020 Jan;     [PubMed PMID: 31613503]
[2] Badalahu,Qin B,Luo J,Zeng Y,Fu S,Zhang L, Classification of the subtalar articular surface and its matching situation: an anatomical study on Chinese subtalar joint. Surgical and radiologic anatomy : SRA. 2020 Feb 28;     [PubMed PMID: 32112282]
[3] Luibil N,Lopez MJ,Patel BC, Anatomy, Head and Neck, Orbit 2020 Jan;     [PubMed PMID: 30969665]
[4] Abdelhady A,Patel BC,Motlagh M,Al Aboud DM, Anatomy, Head and Neck, Eye Superior Oblique Muscle 2020 Jan;     [PubMed PMID: 30725837]
[5] Singh O,Varacallo M, Anatomy, Head and Neck, Frontal Bone 2020 Jan;     [PubMed PMID: 30571045]
[6] Chung IH,Han J,Iwata J,Chai Y, Msx1 and Dlx5 function synergistically to regulate frontal bone development. Genesis (New York, N.Y. : 2000). 2010 Nov;     [PubMed PMID: 20824629]
[7] Tyler MS, Development of the frontal bone and cranial meninges in the embryonic chick: an experimental study of tissue interactions. The Anatomical record. 1983 May;     [PubMed PMID: 6881551]
[8] Katori Y,Rodríguez-Vázquez JF,Kawase T,Murakami G,Cho BH,Abe S, Early fetal development of hard tissue pulleys for the human superior oblique and tensor veli palatini muscles. Annals of anatomy = Anatomischer Anzeiger : official organ of the Anatomische Gesellschaft. 2011 Mar;     [PubMed PMID: 21334866]
[9] Rodríguez-Vázquez JF,Honkura Y,Katori Y,Murakami G,Abe H, Fetal development of the pulley for muscle insertion tendons: A review and new findings related to the tensor tympani tendon. Annals of anatomy = Anatomischer Anzeiger : official organ of the Anatomische Gesellschaft. 2017 Jan;     [PubMed PMID: 27693602]
[10] Haładaj R,Polguj M,Topol M, Anatomical Variations of the Supraorbital and Supratrochlear Nerves: Their Intraorbital Course and Relation to the Supraorbital Margin. Medical science monitor : international medical journal of experimental and clinical research. 2019 Jul 13;     [PubMed PMID: 31301129]
[11] Freter S,Fleenor SJ,Freter R,Liu KJ,Begbie J, Cranial neural crest cells form corridors prefiguring sensory neuroblast migration. Development (Cambridge, England). 2013 Sep;     [PubMed PMID: 23942515]
[12] Agorgianitis L,Panagouli E,Tsakotos G,Tsoucalas G,Filippou D, The Supratrochlear Artery Revisited: An Anatomic Review in Favor of Modern Cosmetic Applications in the Area. Cureus. 2020 Feb 29;     [PubMed PMID: 32257686]
[13] Shumrick KA,Smith TL, The anatomic basis for the design of forehead flaps in nasal reconstruction. Archives of otolaryngology--head     [PubMed PMID: 1554465]
[14] Walker HM,Chauhan PR, Anatomy, Head and Neck, Glabella 2020 Jan;     [PubMed PMID: 32310453]
[15] Kleintjes WG, Forehead anatomy: arterial variations and venous link of the midline forehead flap. Journal of plastic, reconstructive     [PubMed PMID: 17485046]
[16] Cai XY,Li ZM,Xu YB,Cheng G,Luo P, [The anatomic features of supratrochlear artery]. Zhonghua zheng xing wai ke za zhi = Zhonghua zhengxing waike zazhi = Chinese journal of plastic surgery. 2009 Nov;     [PubMed PMID: 20209940]
[17] Brodland DG, Paramedian forehead flap reconstruction for nasal defects. Dermatologic surgery : official publication for American Society for Dermatologic Surgery [et al.]. 2005 Aug;     [PubMed PMID: 16042928]
[18] Germann AM,Al Khalili Y, Anatomy, Head and Neck, Scalp Veins 2020 Jan;     [PubMed PMID: 31082005]
[19] Cai X,Li Z, [Applied anatomy study of supratrochlear vein in reconstruction of nasal defect]. Zhongguo xiu fu chong jian wai ke za zhi = Zhongguo xiufu chongjian waike zazhi = Chinese journal of reparative and reconstructive surgery. 2009 Feb;     [PubMed PMID: 19275108]
[20] Janis JE,Hatef DA,Hagan R,Schaub T,Liu JH,Thakar H,Bolden KM,Heller JB,Kurkjian TJ, Anatomy of the supratrochlear nerve: implications for the surgical treatment of migraine headaches. Plastic and reconstructive surgery. 2013 Apr;     [PubMed PMID: 23249981]
[21] Gras-Cabrerizo JR,Martel-Martin M,Garcia-Lorenzo J,Rodríguez-Álvarez F,Montserrat-Gili JR,Mirapeix-Lucas R,Massegur-Solench H, Surgical Anatomy of the Medial Wall of the Orbit in 14 Human Cadavers. Journal of neurological surgery. Part B, Skull base. 2016 Dec;     [PubMed PMID: 27857868]
[22] Ortiz R,Gfrerer L,Hansdorfer MA,Nealon KP,Lans J,Austen WG Jr, Migraine Surgery at the Frontal Trigger Site: An Analysis of Intraoperative Anatomy. Plastic and reconstructive surgery. 2020 Feb;     [PubMed PMID: 31985652]
[23] Kikuta S,Yalcin B,Iwanaga J,Watanabe K,Kusukawa J,Tubbs RS, The supraorbital and supratrochlear nerves for ipsilateral corneal neurotization: anatomical study. Anatomy     [PubMed PMID: 32274242]
[24] Olinevich VB,Ziangirova GG, [Embryogenesis and structural-and-functional specificity of corneal nerves in health and pathology]. Vestnik oftalmologii. 2004 Jul-Aug;     [PubMed PMID: 15384854]
[25] Eghrari AO,Riazuddin SA,Gottsch JD, Overview of the Cornea: Structure, Function, and Development. Progress in molecular biology and translational science. 2015;     [PubMed PMID: 26310146]
[26] Konschake M,Burger F,Zwierzina M, Peripheral Nerve Anatomy Revisited: Modern Requirements for Neuroimaging and Microsurgery. Anatomical record (Hoboken, N.J. : 2007). 2019 Aug;     [PubMed PMID: 30951264]
[27] Bradford BD,Lee JW, Reconstruction of the Forehead and Scalp. Facial plastic surgery clinics of North America. 2019 Feb;     [PubMed PMID: 30420075]
[28] Shin A,Yoo L,Chaudhuri Z,Demer JL, Independent passive mechanical behavior of bovine extraocular muscle compartments. Investigative ophthalmology     [PubMed PMID: 23188730]
[29] Pauzenberger R,Pikula R,Berchtold V,Mühlbacher J,Rieger UM, Anatomy of the supratrochlear nerve: implications for the surgical treatment of migraine headaches. Plastic and reconstructive surgery. 2014 May;     [PubMed PMID: 24776587]
[30] Turhan-Haktanir N,Ayçiçek A,Haktanir A,Demir Y, Variations of supraorbital foramina in living subjects evaluated with multidetector computed tomography. Head     [PubMed PMID: 18642294]
[31] Domeshek LF,Hunter DA,Santosa K,Couch SM,Ali A,Borschel GH,Zuker RM,Snyder-Warwick AK, Anatomic characteristics of supraorbital and supratrochlear nerves relevant to their use in corneal neurotization. Eye (London, England). 2019 Mar;     [PubMed PMID: 30262895]
[32] Konofaos P,Soto-Miranda MA,Ver Halen J,Fleming JC, Supratrochlear and supraorbital nerves: an anatomical study and applications in the head and neck area. Ophthalmic plastic and reconstructive surgery. 2013 Sep-Oct;     [PubMed PMID: 23928468]
[33] Erdogmus S,Govsa F, Anatomy of the supraorbital region and the evaluation of it for the reconstruction of facial defects. The Journal of craniofacial surgery. 2007 Jan;     [PubMed PMID: 17251847]
[34] Sertel S,Pasche P, Pericranial Flap for Inner Lining in Nasal Reconstruction. Annals of plastic surgery. 2016 Oct;     [PubMed PMID: 26418782]
[35] Park SS, Reconstruction of nasal defects larger than 1.5 centimeters in diameter. The Laryngoscope. 2000 Aug;     [PubMed PMID: 10942120]
[36] Sadashivam S, Isolated Orbital Roof Fracture: Can It Be Catastrophic? Asian journal of neurosurgery. 2018 Jul-Sep;     [PubMed PMID: 30283587]
[37] Liu H,Hu S,Qin W, Traumatic prolapse of the globe into the anterior cranial fossa: a case report. BMC ophthalmology. 2020 Apr 3;     [PubMed PMID: 32245433]
[38] Lopez J,Pineault K,Pradeep T,Khavanin N,Kachniarz B,Faateh M,Grant MP,Redett RJ,Manson PN,Dorafshar AH, Pediatric Frontal Bone and Sinus Fractures: Cause, Characteristics, and a Treatment Algorithm. Plastic and reconstructive surgery. 2020 Apr;     [PubMed PMID: 32221225]
[39] Lofrese G,Mongardi L,De Bonis P,Scerrati A,Nicassio N,Cultrera F, Spontaneous Repositioning of Isolated Blow-In Orbital Roof Fracture: Could Wait and See Be a Strategy in Asymptomatic Cases? The Journal of craniofacial surgery. 2020 Feb 11;     [PubMed PMID: 32049903]
[40] Gómez Roselló E,Quiles Granado AM,Artajona Garcia M,Juanpere Martí S,Laguillo Sala G,Beltrán Mármol B,Pedraza Gutiérrez S, Facial fractures: classification and highlights for a useful report. Insights into imaging. 2020 Mar 19;     [PubMed PMID: 32193796]
[41] Salam GA, Regional anesthesia for office procedures: part I. Head and neck surgeries. American family physician. 2004 Feb 1;     [PubMed PMID: 14971840]
[42] Herlich A, Focused local anesthesia and analgesia for head and neck surgery. International anesthesiology clinics. 2012 Winter;     [PubMed PMID: 22227420]
[43] Novitch M,Hyatali FS,Jeha G,Motejunas M,Bonneval L,Pankaj T,Cornett EM,Jones MR,Kaye RJ,Urman RD,Kaye AD, Regional techniques for head and neck surgical procedures. Best practice     [PubMed PMID: 31791557]
[44] Lee HJ,Choi KS,Won SY,Apinuntrum P,Hu KS,Kim ST,Tansatit T,Kim HJ, Topographic Relationship between the Supratrochlear Nerve and Corrugator Supercilii Muscle--Can This Anatomical Knowledge Improve the Response to Botulinum Toxin Injections in Chronic Migraine? Toxins. 2015 Jul 17;     [PubMed PMID: 26193317]
[45] Filipović B,de Ru JA,van de Langenberg R,Borggreven PA,Lacković Z,Lohuis PJFM, Decompression endoscopic surgery for frontal secondary headache attributed to supraorbital and supratrochlear nerve entrapment: a comprehensive review. European archives of oto-rhino-laryngology : official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery. 2017 May;     [PubMed PMID: 28124109]
[46] Gfrerer L,Guyuron B, Surgical treatment of migraine headaches. Acta neurologica Belgica. 2017 Mar;     [PubMed PMID: 28013487]
[47] Khan TT,Colon-Acevedo B,Mettu P,DeLorenzi C,Woodward JA, An Anatomical Analysis of the Supratrochlear Artery: Considerations in Facial Filler Injections and Preventing Vision Loss. Aesthetic surgery journal. 2017 Feb;     [PubMed PMID: 27530765]
[48] Cho KH,Dalla Pozza E,Toth G,Bassiri Gharb B,Zins JE, Pathophysiology Study of Filler-Induced Blindness. Aesthetic surgery journal. 2019 Jan 1;     [PubMed PMID: 29873688]
[49] Li X,Du L,Lu JJ, A Novel Hypothesis of Visual Loss Secondary to Cosmetic Facial Filler Injection. Annals of plastic surgery. 2015 Sep;     [PubMed PMID: 26207560]
[50] Allali J,Bernard A,Assaraf E,Bourges JL,Renard G, [Multiple embolizations of the branches of the ophthalmic artery: an unknown serious complication of facial surgeries]. Journal francais d'ophtalmologie. 2006 Jan;     [PubMed PMID: 16465125]
[51] Wu S,Pan L,Wu H,Shi H,Zhao Y,Ji Y,Zeng H, Anatomic Study of Ophthalmic Artery Embolism Following Cosmetic Injection. The Journal of craniofacial surgery. 2017 Sep;     [PubMed PMID: 28749836]