Medical Terminology Daily (MTD) is a blog sponsored by Clinical Anatomy Associates, Inc. as a service to the medical community. We post anatomical, medical or surgical terms, their meaning and usage, as well as biographical notes on anatomists, surgeons, and researchers through the ages. Be warned that some of the images used depict human anatomical specimens.

You are welcome to submit questions and suggestions using our "Contact Us" form. The information on this blog follows the terms on our "Privacy and Security Statement" and cannot be construed as medical guidance or instructions for treatment.

We have 277 guests online

A Moment in History

Jean-Louis Petit

Jean Louis Petit
(1674 – 1750)

French surgeon and anatomist, Jean Louis Petit was born in Paris in on March 13, 1674.  His family rented an apartment at his house to Alexis Littre (1658 – 1726), a French anatomist. Petit became an apprentice of Littre at seven years of age, helping him in the dissections for his lectures and at an early age became the assistant in charge of the anatomic amphitheater.

Because of Petit’s dedication to anatomy and medicine, in 1690 at the age of sixteen, became a disciple of a famous Paris surgeon, Castel.

In 1692, Petit entered the French army and performed surgery in two military campaigns. By 1693 he started delivering lectures and was accepted as a great surgeon, being invited to the most difficult operations.  In 1700 he was appointed Chief Surgeon of the Military School in Paris and in the same year he received the degree of Master of Surgery from the Faculty of Paris.

In 1715 he was made a member of the Royal Academy of Sciences and an honorary member of the Royal Society of London. He was appointed by the King as the first Director General of the Royal Academy of Surgery when it was founded in 1731.

Petit’s written works are of historical importance.  “Traite des Maladies des Os” ( A Treatise on Bone Diseases);  “Traite des Maladies Chirurgicales et des Operation” (A Treatise on Surgical Diseases and their Operations” This last book was published posthumously in 1774. He also published a monograph on hemorrhage, another on lachrymal fistula, and others.

He was one of the first to perform choIecystotomy and mastoidotomy. His original tourniquet design for amputations saved many in the battlefield and the design of the same surgical instrument today has not changed much since its invention by him.

His name is remembered in the lumbar triangle, also called the "triangle of Petit", and the abdominal hernia that can ensue through that area of weakness, the lumbar hernia or "Petit's hernia".

Sources:
1. “Jean Louis Petit – A Sketch of his Life, Character, and Writings” Hayne, AP San Fran Western Lancet 1875 4: 446-454
2. “Oeuvres compl?tes de Jean-Louis Petit” 1837 Imprimerie de F. Chapoulaud
3. Extraits de l'eloge de Jean-Louis Petit Ius dans Ia seance publique de I' Academie royale de chirurgie du 26 mai 1750” Louis A. Chirurgie 2001: 126 : 475- 81

 "Clinical Anatomy Associates, Inc., and the contributors of "Medical Terminology Daily" wish to thank all individuals who donate their bodies and tissues for the advancement of education and research”.

Click here for more information

abebooks banner

bookplateink.com

 

 

Temporal muscle

Published: Tuesday, January 17, 2017 07:00 | Written by: Fernanda Cortes, DDS, MSc | Hits: 4725

The temporal muscle (Lat:Temporalis) is a bilateral muscle located on the side of the head. It belongs to a subgroup of head muscles called Masticatory Muscles, named after their function elevating the mandible to produce the mandible movements (1,2). Masticatory muscles are four per side: Temporalis, Masseter, Pterygoideus medialis and Pterygoideus lateralis (1,2).

The temporalis muscle is a fan-shaped muscle which occupies the temporal fossa from which its fascicles (fibers) converge to the coronoid process of the mandible. Classic description for this muscle recognizes three main muscular bodies (anterior, midle, and posterior) originated from the temporal fossa up to the lower temporalis line and the temporalis fascia, fascicles which descend through the inner part de the zygomatic arch converging to be inserted on the coronoid process of the mandible, its temporalis crest and anterior margin of the mandibular branch through thick tendons (1,2).

In 1996 Dunn et al. (3) reported the discovery of a so far unknown masticatory muscle called the “sphenomandibularis”, originated from the greater wing of the sphenoid bone medial to the temporalis muscle and descends on an oblique (lateral and slightly posterior) fashion reaching distally the coronoid process of the mandible. This muscular portion has been recognized as the “deep belly of the temporalis muscle” and has been described by several authors since then (4,5,6,8). The importance that has been given to this particular bundle lies on the fact that its medial insertion can reach a close relationship to the foramen rotundum, place of emergency from the cranium of the maxillary nerve, which has been hypothesized, could lead to eventual alteration of this nerve if it got trapped by this part of the muscle (6, 7).

The temporalis muscle receives innervation fundamentally from branches of the mandibular nerve: Deep temporal nerve (N. temporalis profundus)through its anterior middle and posterior branches.

The temporalis muscle is covered by a thick fascia layer: the temporalis fascia.

Article written by: Maria F. Cortés, DDS, MSc.

Images from:
Fig 1. Public domain, by Henry Vandyke Carter, MD - Gray's Anatomy, 1918
Fig 2. Geers C, Nyssen-Behets C, Cosnard G, Lengelé B. The deep belly of the temporalis muscle: an anatomical, histological and MRI study. Surg Radiol Anat. 2005 Aug;27(3):184-91. Epub 2005 Apr 9

Temporalis muscle
Temporalis muscle
Click on the image for a larger depiction
Sources:
1. “Anatomía humana” V.2. Latarjet- Ruiz Liard, 4ª ed. 6ª reimp. 2008 Médica Panamericana, Buenos Aires, Argentina.
2. “Anatomía humana: descriptiva, topográfica y funcional. Tomo 1. Cabeza y Cuello, Rouviere H – Delmas A, 11° ed. 2005 MASSON, S.A., Barcelona, Spain.
3. Dunn GF, Hack GD, Robinson WL, Koritzer RT. Anatomical observation of a craniomandibular muscle originating from the skull base: the sphenomandibularis. Cranio. 1996 Apr;14(2):97-103; discussion 104-5.
4. Shimokawa T, Akita K, Soma K, Sato T. Innervation analysis of the small muscle bundles attached to the temporalis: truly new muscles or merely derivatives of the temporalis? Surg Radiol Anat. 1998;20(5):329-34.
5. Akita K, Shimokawa T, Sato T. Aberrant muscle between the temporalis and the lateral pterygoid muscles: M. pterygoideus proprius (Henle). Clin Anat. 2001 Jul;14(4):288-91.
6. Schön Ybarra MA, Bauer B. Medial portion of M. Temporalis and its potential involvement in facial pain. Clin Anat. 2001;14(1):25-30.
7. Fuentes E, Llanos S, Gómez R, Llanos P, Llanos F, Cortés-Sylvester MF, Solaria P, Melian A, Asfura J, Santos M, Zamorano E. Discovery of deep temporalis muscle belly close to maxillary nerve in a patient with trigeminal neuralgia: hypothesis of muscular compression and case report treated by Botox® Onabotulinum toxin tipe-A. Chirurgia 2016 June;29(3):99-102
8. Geers C, Nyssen-Behets C, Cosnard G, Lengelé B. The deep belly of the temporalis muscle: an anatomical, histological and MRI study. Surg Radiol Anat. 2005 Aug;27(3):184-91. Epub 2005 Apr 9.
MTD Main Page Subscribe to MTD