Skip to main content

Acetabular Canal. Part 3.

 

Acetabular CanalPart 3

S.V. Arkhipov, Independent Researcher, Joensuu, Finland


Abstract

This article describes the space where the ligamentum capitis femoris (LCF) attaches and functions. See also Part 1 and Part 2.

 

The Significance of the Acetabular Canal

The acetabular canal contains the main areas of attachment for the LCF (ligamentum capitis femoris). Its distal end attaches to the femoral head, while the proximal end connects to the fossa and notch of the acetabulum. The primary purpose of the acetabular canal is to ensure the normal functioning of the LCF. Normally, the LCF should not come into contact with the joint surfaces. Therefore, the length of the LCF should not exceed the diameter of the acetabular fossa, i.e., the diameter of the central section of the acetabular canal Its depth should be less than the thickness of the LCF.



Figure 1. Lateral wall of the acetabular canal and LCF; the bottom of the acetabulum is removed (from 1908GrayH). 

The diameter and depth of the acetabular fossa, and thus the acetabular canal, are critical dimensions for the LCF. A reduction in depth results in the bottom of the acetabular fossa approaching the articular surface of the femoral head, which has been observed by us and other authors in the older age group (1972ПодрушнякЕП; 2012АрхиповСВ). In this case, the LCF becomes compressed between the lateral wall of the acetabular canal—the cartilage surface of the femoral head—and the medial wall, the bottom of the acetabular fossa, covered by synovial and adipose tissue. Figuratively speaking, even in a normal state, the LCF is constantly caught "between Scylla and Charybdis." Continuing with this analogy, it can be said that the compressed LCF within the acetabular canal will inevitably be destroyed, much like the ships destroyed by the clashing rocks of the Symplegades in Greek mythology. The gradual compression of the LCF leads to its flattening and thinning due to abrasion, as well as histological transformation. As the LCF becomes fragile, it tears under what were previously normal stretching loads.


Visualization of the Acetabular Canal

Due to the deep location of the hip joint, it is impossible to palpate the entrance to the acetabular canal, let alone see it with the naked eye. The acetabular canal only exists when the femoral head and the acetabulum are in articulation. In ancient times, the contents of the acetabular canal were studied during post-mortem dislocation of the femoral head. It was first observed during the preparation of a deceased body for burial. The first post-mortem arthrotomy of the hip joint with hip disarticulation is presumed to have occurred in Morocco 15,000-12,500 years ago (2016MariottiV_CondemiS). Remains of a human aged 8,000-4,500 years with signs of hip disarticulation were discovered in southern China (2024YeZ_LiFJ). The acetabular canal was also examined during the preparation of bodies for mummification. The oldest embalmed body discovered in Chile is approximately 7,900±180 years old (1984AllisonMJ_LowensteinJM).

It seems that the first physicians to observe the acetabular canal were Herophilus of Chalcedon and Erasistratus of Ceos. These anatomists, in the 3rd-2nd century BCE, conducted hundreds of dissections in Alexandria (1831CelsusAC). The first to propose access to the acetabular canal by removing the anterior wall of the acetabulum was P.N. Gerdy (1833). The first successful penetration into the acetabular canal from the pelvic side was performed by W. Weber and E. Weber, who drilled a hole in the bottom of the acetabular fossa (1836WeberW_WeberE). The contents of the acetabular canal were first observed from the medial side by J. Struthers and G.M. Humphry. They made an opening in the bottom of the acetabular fossa (1858StruthersJ; 1858HumphryGM).


 Figure 2. Lateral wall of the acetabular canal and LCF; the bottom of the acetabulum is removed (from 1904FickR). 

Today, the study of the acetabular canal is inconceivable without the use of instrumental methods. Its visualization is available radiologically, for example, via plain radiography of the hip joint.


Figure 3. The acetabular canal (indicated by an arrow) in a radiograph; top – fragment of a standard anteroposterior X-ray of the hip joint; bottom – X-ray of the hip joint in the axial projection by Launstein (personal observation).


In radiography, the transverse ligament in the outer segment of the peripheral part of the acetabular canal is indistinguishable. As a result, this segment appears larger in cross-section on the X-ray than in reality. In children, the contents of the acetabular canal can be visualized using ultrasound.

Radiography allows visualization of the medial and lateral walls of the acetabular canal. A detailed view of its shape and dimensions can be obtained using computed tomography (CT) of the hip joint.


Figure 4. The acetabular canal (indicated by an arrow) visualized by computed tomography; top – fragment of a horizontal scan of the hip joint; bottom – fragment of a frontal scan of the hip joint (personal observation).


Three-dimensional reconstruction of CT scans of the hip joint enables visualization of the "entrance" to the acetabular canal, specifically the external opening of the acetabular notch.


Figure 5. External opening of the acetabular canal ("entrance" indicated by an arrow), 3D reconstruction of computed tomography; top – hip joint, front view; bottom – hip joint, bottom view (personal observation).


Viewed from below during X-ray tomography, the "entrance" to the acetabular canal has a pear-shaped form. It is wider at the back and narrower at the front. In cases of hip joint trauma, the configuration of the external opening leading to the acetabular canal may change.


Figure 6. Change in the configuration of the entrance to the acetabular canal (indicated by an arrow) in case of a fracture of the acetabular fossa with dislocation of the femoral head outward (3D reconstruction from computed tomography, bottom view, personal observation).


In some cases, CT of the hip joint reveals a shadow of the LCF in the acetabular canal. More detailed visualization of the contents of the acetabular canal can be achieved using magnetic resonance imaging (MRI) of the hip joint.


Figure 7. The acetabular canal on magnetic resonance imaging, the shadow of the LCF indicated by an arrow; top – fragment of a horizontal scan of the hip joint; bottom – fragment of a frontal scan of the hip joint (personal observation).


MRI, especially with contrast, allows differentiation of the contents of the acetabular canal: LCF, adipose tissue accumulation, cartilage surfaces, synovial fluid, synovial membrane folds, and the transverse ligament of the acetabulum.

As age increases, the depth of the acetabular fossa decreases and may even disappear entirely (1972ПодрушнякЕП). We observed the absence of the acetabular canal in the fourth stage of osteoarthritis. 


Figure 8. View of a hip joint affected by osteoarthritis of the fourth degree; area of the acetabular canal filled with newly formed bone tissue indicated by an arrow (fragment of a standard anteroposterior X-ray, personal observation).


The fossa and notch of the acetabulum usually disappear in protrusion coxarthrosis. Additionally, the acetabular canal may become filled with fibrous tissue, osteophytes, chondral bodies, and cartilage fragments. Newly formed bone and scar tissue, a deformed acetabular fossa, free joint bodies, as well as osteophytes from the deformed femoral head and the internal edges of the lunate surface, lead to damage of the LCF during movement (see Pathology of the Acetabular Canal). We believe this is one of the reasons for the disappearance of the LCF.


References

Allison MJ, Focacci G, Arriaza B, Standen V, Rivera M, Lowenstein JM. Chinchorro, momias de preparación complicada: métodos de momificación. Chungara: Revista de Antropología Chilena. 1984;13:155-73.

Celsus AC. On medicine, in eight books, Latin and English. Translated from L. Targa's edition, the words of the text being arranged in the order of construction. To which are prefixed, a life of the author, tables of weights and measures, with explanatory notes, etc. designed to facilitate the progress of medical students. By Alex. Lee, A.M., Surg. In two volumes. London: E. Cox, MDCCCXXXI [1831].

Gerdy PN. Physiologie médicale, didactique et critique. T. 1. Paris: Librairie de Crochard, 1833.

Gray H. Anatomy, descriptive and surgical; 17th ed. Philadelphia, New York: Lea & Febiger, 1908. 

Fick R. Handbuch der Anatomie und Mechanik der Gelenke: Erster Teil: Anatomie der Gelenke. Jena: G. Fischer, 1904. 

Humphry GM. A Treatise on the Human Skeleton including the Joints. Cambridge: MacMillan and Company, 1858.

Mariotti V, Belcastro MG, Condemi S. From corpse to bones: funerary rituals of the Taforalt Iberomaurusian population. Bulletins et Memoires de la Societe d'Anthropologie de Paris. 2016;28(1-2)60-5. 

Struthers J. Demonstration of the use of the round ligament of the hip joint. Edinburgh Med J. 1858;4(5)434-42. 

Weber W, Weber E. Mechanik der menschlichen Gehwerkzeuge: eine anatomisch-physiologische Untersuchung. Gottingen: Dietrichsche Buchhandlung, 1836.

Ye Z, Wang M, Stock JT, Li FJ. Disarticulation, evisceration and excarnation: Neolithic mortuary practices at Dingsishan, southern China. Antiquity. 2024;98(399)616-35. 

Архипов СВ. Роль связки головки бедренной кости в патогенезе коксартроза: дис. … канд. мед. наук. Москва, 2012. 

Подрушняк ЕП. Возрастные изменения суставов человека. Киев: Здоров‘я, 1972. 


Keywords

ligamentum capitis femoris, ligamentum teres, ligament of head of femur, acetabular canal, anatomy, attachment


                                                                     

NB! Fair practice / use: copied for the purposes of criticism, review, comment, research and private study in accordance with Copyright Laws of the US: 17 U.S.C. §107; Copyright Law of the EU: Dir. 2001/29/EC, art.5/3a,d; Copyright Law of the RU: ГК РФ ст.1274/1.1-2,7





Comments

Popular posts from this blog

LCF in 2025 (March)

  LCF in 2025 ( March ):  Quotes from articles and books published in March 2025 mentioning the ligamentum capitis femoris.   Matsushita, Y., Sugiyama, H., Hayama, T., Sato, R., & Saito, M. (2025). Long-term Outcome of Pediatric Arthroscopic Surgery for Avulsion Fracture of the Ligamentum Teres: A Case Report. JBJS Case Connector ,  15 (1), e25.   [i]     journals.lww.com   Arkhipov, S. V. (2025). Inferior Portal for Hip Arthroscopy: A Pilot Experimental Study. Pt. 2. Inferior Portal Prototypes.  About Round Ligament of Femur . February 26, 2025.  [ii]   researchgate . net   Pfirrmann, C. W., & Kim, Y. J. (2025). Advanced Imaging. In  Surgical Hip Dislocation: A Comprehensive Approach to Modern Hip Surgery (pp. 29-42). Cham: Springer Nature Switzerland.  [iii]    link.springer.com   Singh, R., & Yadav, N. (2025). Morphometry and Morphology of the Fovea Capitis of the Femoral Head an...

1836-1840PartridgeR

  «Prof. Partridge in his lectures on anatomy at King's College was accustomed to compare the Ligamentum Teres, in its function, to the leathern straps by which the body of a carriage is suspended on springs » ( 1874SavoryWS ). Perhaps Nikolai Pirogov listened to these lectures ( 1859PirogoffN ).   The analogy that Richard Partridge used could have arisen after reading the monograph Bell J. The Principles of Surgery (1801) . In it, the author depicted a cart and a pelvis resting on the head of one and two femurs. However, there is no mention of ligamentum capitis femoris (LCF) in the chart descriptions. References Savory WS. On the use of the ligamentum teres of the hip joint. J Anat Physiol. 1874;8(2)291-6.    [ ncbi.nlm.nih.gov  ,    archive.org ] Pirogoff N. Anatome topographica sectionibus per corpus humanum congelatum triplici directione ductus illustrate. Petropoli: Typis Jacobi Trey, 1859.   [ books.google  ,   archive.org ] ...

2000-1600bcBM29663

  Fragment of the text of clay tablet BM 29663 (Mesopotamia, 2000-1600 BC). In the list of body parts of a sheep, the author indicates ligamentum capitis femoris (LCF). See our commentary at the link: 2000-1600bcBM29663 [Rus]. Quote [Akk] Clay tablet BM 29663 (original source: photo - British Museum  britishmuseum.org , text - 2018CohenY , p. 134). Translation [Eng] List of Sheep Body Parts ( с lay tablet BM 29663, obverse) 10. ni-im-šu → nimšu, “sciatic nerve”, “sinew” . ( original source: 2018CohenY , p. 135). ( original source: British Museum  britishmuseum.org ,  CC BY-NC-SA 4.0)  External links Clay tablet; museum number 29663; registration number 1898,1115.49. Middle East, Old Babylonian period (2000-1600 BC). [ britishmuseum.org  ,  cdli.mpiwg-berlin.mpg.de ] Sigrist M, Zadok R, Walker C. Catalogue of the Babylonian tablets in the British Museum. Catalogue of the Babylonian tablets in the British Museum. London: British Museum Press, 2006. ...

2020ArkhipovSV_ProlyginaIV

  Ancient Textual Sources on Ligamentum Teres: Context and Transmission S.V. Arkhipov, I.V. Prolygina   KEYWORDS: ancient medicine; ancient traumatology; Galen; Hippocrates; hip joint; ligamentum capitis femoris; ligament of head of femur; ligamentum teres. SUMMARY Background. One of the least researched anatomical structures of the human body is the ligament of head of femur, most often referred to as ligamentum teres. The history of the nomination of this term, medical contexts of its use, the etymology and the first synonyms (Figure 1) are not sufficiently understood. Purpose. The purpose of the article is to present the most complete collection of evidence from ancient medical authors about the term ligamentum teres, trace the history of its nomination and analyze the gradual changes in the level of knowledge about the anatomy, mechanical and geometric properties of this structure, its pathology and treatment methods. Methods. The study is based on an inter...

A FORCE THAT HELPS ROTATE THE PELVIS

   A force that helps rotate the pelvis when walking. Modeling the key movement of the ligamentum capitis femoris when walking (the simplest but most visual experiments). See: https://kruglayasvyazka.blogspot.com/2024/05/blog-post_29.html #ligamentum_teres   #ligamentum_capitis_femoris   #hip   #biomechanics    Publication in the facebook group 03/24/2025.                                                                                                                     BLOG CONTENT NEWS AND ANNOUNCEMENTS FACEBOOK

EXTERNAL LIGAMENTS & LCF

  external ligaments & LCF First experiments to study the interaction of the external ligaments and the ligamentum capitis femoris in a model: https://kruglayasvyazka.blogspot.com/2024/06/blog-post_6.html Pathological consequences of lengthening of the ligamentum capitis femoris: https://kruglayasvyazka.blogspot.com/2024/06/blog-post_63.html   norm: https://kruglayasvyazka.blogspot.com/2024/06/blog-post_50.html   #ligamentum_teres   #ligamentum_capitis_femoris   #hip   #biomechanics    Publication in the facebook group 03/27/2025.                                                                                                                     BLOG CONTE...

FACEBOOK

  FACEBOOK (publications in the group LIGAMENTUM CAPITIS FEMORIS and this social network) A FACEBOOK section has been created (About publications in this social network). FACEBOOK GROUP  On creating a group.  OLDEST SYNONYMS  Post in Facebook groups. Planar models of the hip joint   Post in Facebook groups. The loading acting onthe femoral head   Post in Facebook groups. Visualization of the LCF by the medial approach   Post in Facebook groups. A FORCE THAT HELPS ROTATE THE PELVIS   Post in Facebook groups.  FIRST EXPERIMENTS ON A MECHANICAL MODEL   Post in Facebook groups. HIP JOINT MODEL WITH LCF ANALOGUE   Post in Facebook groups. EXTERNAL LIGAMENTS & LCF   Post in Facebook groups.  BIOMECHANICS OF THE HIP JOINT WITHOUT LCF   Post in Facebook groups. F. Pauwels vis-à-vis S. Arkhipov ☺   Post in Facebook groups.                           ...

Online Journal «ABOUT ROUND LIGAMENT OF FEMUR», March 2025

  The publication is dedicated to the ligamentum capitis femoris (LCF) and related topics.   About the Journal »»»                                                                                . The online journal  « About Round Ligament of  Femur »   was created based on the scientific blog of the same name. The resource is the English-language part of the project:  ONLINE JOURNAL:  Ligamentum capitis femoris . Updates:  As new materials are prepared. Purpose:  Popularization and preservation of knowledge about LCF, as well as promoting its practical application. Main goal:  Improvement of diagnosis, treatment, and prevention of injuries and diseases of the hip joint. Publisher: Arkhipov S.V., independent researcher, PhD, ortho...

1956SingerCJ

Fragment from the book Singer CJ (Ed., trans.). On anatomical procedures: De anatomicis administrationibus (1956). Galen writes about the high resiliency and hardness of ligamentum capitis femoris (LCF), and also notes its connective function. See our commentary at the link: 1956SingerCJ [Rus], and  2020ArkhipovSV_ProlyginaIV .  Quote. p. 55. [Eng] On anatomical procedures; Book II. Chapter 10. As with the arm you examined the ligaments of the bones, so now examine those of all the exposed joints and first of the hip. This has one ligament embracing it [capsular ligament], as with all joints. A second, hidden in the depths of the joint [ligamentum teres], ties the head of the femur to the hollow in the hip-bone [acetabulum]. It is so tough that it could be called a 'cartilaginous sinew'. (Transl. by Ch. Singer; original source: 1821KühnCG ). External links Singer CJ (Ed., trans.). On anatomical procedures: De anatomicis administrationibus. London, New York, Toronto: P...

922-722bcElohist

  Excerpt from the book of Bereishit (Genesis), the lost biblical source Elohist, written in Paleo-Hebrew script. A variant of the oldest description of damage to the ligamentum capitis femoris (LCF) and the cause of lameness in Hebrew, dating from 922-722 BCE. See our commentary at the link: 922-722bcElohist [Rus]. Quote [ Paleo-Hebrew ] Elohist. Bereshit 32:32-33 (original source: 5784 Moshe Ben Amram, p. 41;  our correction) Translation [Eng] Elohist. Bereshit 32:32-33 and the sun riseth on him when he hath passed over Penuel, and he is halting on his thigh; therefore the sons of Israel do not eat the sinew which shrank, which is on the hollow of the thigh, unto this day, because He came against the hollow of Jacob's thigh, against the sinew which shrank.  (our correction-reconstruction of the version 1898 YoungR ( p. 23, Bereishit 32:32-33); preserved the text of the age of 922-722 BC belonging to the lost biblical source "Elohist") Moshe Ben Amram. Pentateuch in P...