Posterior lacrimal crest

Last updated
Posterior lacrimal crest
Gray163.png
Left lacrimal bone. Orbital surface. Enlarged. (Posterior lacrimal crest visible but not labeled.)
Details
Part of lacrimal bone
System skeletal
Identifiers
Latin crista lacrimalis posterior
TA98 A02.1.09.002
TA2 745
FMA 57609
Anatomical terms of bone

The posterior lacrimal crest is a vertical bony ridge on the orbital surface of the lacrimal bone. It divides the bone into two parts. It gives origin to the lacrimal part of the orbicularis oculi muscle.

Contents

Structure

The posterior lacrimal crest is a vertical bony ridge on the orbital (lateral) surface of the lacrimal bone. It divides the lacrimal bone into two parts. It is quite thin and fragile in most people. [1]

The lacrimal groove is in front of this crest. The inner margin of it unites with the frontal process of the maxilla to complete the fossa for the lacrimal sac. [2] The portion of the lacrimal bone behind the posterior lacrimal crest is smooth, and forms part of the medial wall of the orbit. The lacrimal crest ends below in the lacrimal hamulus (a small hook-like projection), which articulates with the lacrimal tubercle of the maxilla.

Relations

The posterior lacrimal crest is just behind the lacrimal sac, and its upper part lodges the lacrimal sac. [3] [4] The lower part lodges the nasolacrimal duct. Horner's muscle, part of the orbicularis oris muscle, inserts between 2 mm and 4 mm from the posterior lacrimal crest. [5] Together with the thicker and more prominent anterior lacrimal crest, it forms the fossa for the lacrimal sac. [1]

Variation

In most people, the posterior lacrimal crest is fairly prominent. [6] However, in around 20% of people, it is fairly shallow. [6] In contrast, the anterior lacrimal crest is almost always very prominent. [6]

Function

The posterior lacrimal crest gives origin to the lacrimal part of the orbicularis oculi muscle. It also helps to protect the lacrimal sac. [3]

Clinical significance

The posterior lacrimal crest may be vulnerable to avulsion fractures. [7] It is generally quite thin and fragile. [1] 25% of such avulsion fractures are related to a Le Fort III skull fracture. [7]

Additional images

See also

References

PD-icon.svgThis article incorporates text in the public domain from page 164 of the 20th edition of Gray's Anatomy (1918)

  1. 1 2 3 Tao, Hai; Ma, Zhi-zhong; Wu, Hai-Yang; Wang, Peng; Han, Cui (April 2014). "Anatomic study of the lacrimal fossa and lacrimal pathway for bypass surgery with autogenous tissue grafting". Indian Journal of Ophthalmology . 62 (4): 419–423. doi: 10.4103/0301-4738.121137 . ISSN   0301-4738. PMC   4064215 . PMID   24817745.
  2. Tomazic, Peter Valentin; Dewart, Nora; Witterick, Ian J. (2021-01-01), Sindwani, Raj (ed.), "6 - Rhinologic Evaluation in Orbital and Lacrimal Disease", Endoscopic Surgery of the Orbit, Philadelphia: Elsevier, pp. 36–40, ISBN   978-0-323-61329-3 , retrieved 2021-09-23
  3. 1 2 Merbs, Shannath; DeParis, Sarah (2020-01-01), Dorafshar, Amir H.; Rodriguez, Eduardo D.; Manson, Paul N. (eds.), "3.4 - Ocular Considerations: Ectropion, Entropion, Blink, Ptosis, Epiphora", Facial Trauma Surgery, London: Elsevier, pp. 367–378, ISBN   978-0-323-49755-8 , retrieved 2021-09-23
  4. Piniara, Anastasia; Georgalas, Christos (2021-01-01), Sindwani, Raj (ed.), "4 - Surgical Anatomy of the Orbit, Including the Intraconal Space", Endoscopic Surgery of the Orbit, Philadelphia: Elsevier, pp. 18–27, ISBN   978-0-323-61329-3 , retrieved 2021-09-23
  5. Kakizaki, Hirohiko; Ichinose, Akihiro; Takahashi, Yasuhiro; Kang, Hyera; Ikeda, Hiroshi; Nakano, Takashi; Asamoto, Ken; Iwaki, Masayoshi (February 2012). "Anatomical Relationship of Horner's Muscle Origin and Posterior Lacrimal Crest" . Ophthalmic Plastic & Reconstructive Surgery. 28 (1): 66–68. doi:10.1097/IOP.0b013e318239321d. ISSN   0740-9303. PMID   22186989. S2CID   5145634.
  6. 1 2 3 Bisaria, K K; Saxena, R C; Bisaria, S D; Lakhtakia, P K; Agarwal, A K; Premsagar, I C (October 1989). "The lacrimal fossa in Indians". Journal of Anatomy . 166: 265–268. ISSN   0021-8782. PMC   1256759 . PMID   2621144.
  7. 1 2 Díaz, Oswaldo J. Gómez; Carreño, Andrés Parra; Serna, Daniel Restrepo (October 2019). "Traumatic Telecanthus and Posterior Lacrimal Crest Avulsion in a Six-Year-Old Child" . Journal of Craniofacial Surgery. 30 (7): 2224–2226. doi:10.1097/SCS.0000000000005922. ISSN   1049-2275. PMID   31490433. S2CID   201846470.