Ligamentum capitis femoris a pilot an experimental study
S.V. Arkhipov, N.V. Zagorodny, D.V. Skvortsov
Abstract
Ligamentum capitis femoris (syn. ligamentum teres, ligament of head of femur), connecting the acetabulum and the head of femur. This is one of the least studied anatomical elements of the human body. In order to clarify the functions of the ligamentum capitis femoris, external ligaments and abductor muscle group, we constructed a dynamic model of the hip joint. It was established that this anatomical element is involved in constraining the hip joint adduction and may locking the hip joint in the frontal plane, turning it into an analogue of a third-class lever. When the ligamentum capitis femoris is stretched and the abductor muscle group is tension, a load equal to twice the body weight is evenly distributed between the upper and lower hemispheres of the head of femur. The ligamentum capitis femoris function increases the steadiness of the orthostatic postures and unloads the muscle apparatus of the hip joint.
Introduction
Ligamentum capitis femoris (syn. ligamentum teres, ligament of head of
femur) is known for about 2500 years. The first description of the ligamentum
capitis femoris in the medical text is given by Hippocrates of Kos in the
treatise «Instruments of Reductions» (V-IV century BCE) [1]. In the Greek edition of
the manuscript, ligamentum capitis femoris is called νεῦρον [2], while in
the Latin version it is referred to as neruus [3]. According to our
hypothesis, the first in the history of mankind to mention a ligamentum capitis
femoris, is contained in the ancient literary monument of Torah (XII-II century
BCE) [4]. One of the early mentions is contained in the works by Heraclides of
Tarentum (III–II century BCE) [5], Hegetor (II century BCE) [6], Apollonios of Kition (I century BCE) [7] and Galen of Pergamon (II-III century ACE) [5]. However, it remains one of the least studied anatomical
structures of the human body, indeed, a ligamentum incognitum.
The ligamentum capitis femoris is located in the hip joint, in a special
osteochondrous cavity composed of the acetabular notch and cotyloid fossa on
one side and the articular surface of the head of femur on the other side [8].
The normal ligamentum capitis femoris length is about 25 mm [9], a mean ultimate
failure load of 204 N [10], and maybe more about 882 N [11]. Histologically, the basis of the ligamentum
capitis femoris is composed of
collagen fiber bundles and is surrounded by a layer of investing synovium
composed of a single layer of cuboidal cells [12, 13]. The ligamentum
capitis femoris had six anchoring points on the acetabulum and one anchoring point on
the femur [14].
The
biomechanical function of the ligamentum capitis femoris has not been
unambiguously determined [15] and is subject to controversy. Tonkov wrote that
the ligamentum capitis femoris function “… is not perfectly clear; in any case,
its mechanical significance is not so great” [9]. However, according to Neverov
and Shil’nikov, it plays an important role in the hip joint biomechanics [16], while
Vorob’ev claimed that its “biomechanical function” is of importance only under
certain conditions [17]. On the other hand, Pirogov compared the ligamentum
capitis femoris to “a steel spring on which the pelvis is suspended from the
caput” [18]. Gerdy and Savory [19] advanced a similar opinion, the former
author noting that the ligamentum capitis femoris is exerted in the erect
posture. Ivanitskii, when touching on the role of the ligamentum capitis
femoris in maintaining an erect posture, wrote [20], “… in an asymmetrical posture, with the pelvis tilted, the
ligamentum capitis femoris on the side of the supporting, usually straightened,
leg is stretched to reinforce the hip joint” [20].
In hip
joint biomechanics, it is commonly accepted that maintaining an one-support
orthostatic posture in the frontal plane depends only on muscles [21–25]. The
ligamentum capitis femoris is not mentioned as a functional component of the
hip joint, and its mechanical reaction is not considered in calculating the
head of femur loading.
The purpose of this study was to clarify the function of the ligamentum capitis femoris and its role in maintaining one-support orthostatic posture.
Materials and Methods
In order to clarify the functions of the ligamentum capitis femoris and abductor muscle group, we constructed a dynamic model of the hip joint (Figure 1) [26]. We used a Thompson unipolar endoprosthesis fixed on a base, named as a femoral basal element. In accordance with the diameter of the head of endoprosthesis (head of femur analogue), a metal model of the acetabulum was made in the form of a thick-walled spherical shell having a shaped recess that simulated the acetabular fossa and notch. A profiled plane simulated pelvis and a plate for suspending a load, a 1- to 3-kg dumbbell, were attached from the outside. The model contained an ligamentum capitis femoris analogue made from a metal cord 2 mm in diameter and external ligaments analogues (iliofemoral, ischiofemoral, and pubofemorale ligaments) made from a metal cord 1.5 mm in diameter. One end of ligamentum capitis femoris analogue was tightly fixed to an opening made in the shaped recess of the acetabulum model, and the other, to the head of endoprosthesis. Both parts of the model were also linked to a dynamometer, whose spring simulated the function of the abductor muscle group; oil lubricated the friction node. The properties of the model were studied both in the absence of the ligamentum capitis femoris analogue, external ligaments analogues, and abductor muscle group analogues and in their presence in different combinations. In some experiments, we changed the length of the abductor muscle group analogue, thereby modeling different degrees of its tension. We determined the possible rotational and translational movements in the hinge of the model, their range, and constraints. We modeled equilibrium conditions for the pelvis moving in the frontal plane in the unstrained and strained types of one-support orthostatic posture.
Figure 1. Dynamic hip joint model (Application RU2009124926 A, June 29, 2009. 2011.) |
Results and Discussion
Experiments with a dynamic model of the hip joint showed that the ligamentum capitis femoris imposes constraints on the hip joint adduction by limiting abduction, pronation and supination, and translational outward and upward head of femur movements, and also prevents dislocation. Stretching of the ligamentum capitis femoris is brought about by adducting the hip and inclining the pelvis to the nonsupporting side, the hip joint locking in the frontal plane, becoming an analogue of a third-class lever. In the absence of abductor muscle group tension, the resultant force acting on the hip joint is directed upwards, loading only the inner lower part of the head of femur. Our data confirm that straining of the abductor muscle group increases abduction of the hip joint. In cooperation with antagonists, it is capable of locking the hip joint in the frontal plane in an arbitrary position. If the abductor muscle group is exerted without stretching of the ligamentum capitis femoris, the resultant force acting on the head of femur is directed upwards, loading only the inner upper part of the head of femur. The abductor muscle group cooperates with the ligamentum capitis femoris in constraining adduction. Its tightening can decrease the ligamentum capitis femoris stretching, and, vice versa, stretched ligamentum capitis femoris decreases the load on the abductor muscle group.
It was
established experimentally that the ligamentum capitis femoris is not subjected
to stretching in a strained one-support orthostatic posture, while the abductor
muscle group and its antagonists locking the hip joint movements in the frontal
plane. Here, the hip joint is an analogue of a first-class lever, which means
loading of the upper hemisphere of the head of femur. If we assume that the lever
of the body weight exceeds threefold the lever of the abductor muscle group
effort [25], then the force produced by the abductor muscle group will be three
times greater than the body weight. Then, the resultant downward force acting
on the head of femur is four times greater than the body weight.
Analysis
of the experimental data and results of clinical examinations indicates that,
in the unstrained one-support orthostatic posture, hip adduction and tilting of
the pelvis toward nonsupporting side are constrained including by stretching
ligamentum capitis femoris, which agrees with the opinions of other authors
[20, 27]. The pelvis, as stated by Pirogov, is “suspended” from the ligamentum
capitis femoris [18]. The combination of stretching of the ligamentum capitis
femoris and tension of the abductor muscle group is optimal in terms of loading
all elements of hip joint and maintaining the steadiness of the erect posture
in the frontal plane.
Given
this type of a one-support orthostatic posture, both the stretched ligamentum
capitis femoris and the tension abductor muscle group deviate from the
vertical. The horizontal components of the reaction forces of the ligamentum
capitis femoris and the abductor muscle group are summed, resulting in a
horizontal force that uniformly presses the acetabulum to the head of femur.
The mean angular deviation from the vertical of the force produced by the
abductor muscle group is 21°[22]; the angular deviation of the ligamentum
capitis femoris is, according to our data, about 50°. The calculations show
that the amount of pressing the pelvis to the head of femur is approximately
equal to twice the weight of the body (1.96P), with the horizontal
component of the ligamentum capitis femoris reaction force equal to 1.6P and
the horizontal component of the abductor muscle group reaction force equal to
0.36P. The loads on the upper and lower head of femur hemispheres are
approximately equivalent to the body weight without taking into account the
mass of the supporting leg.
In an unstrained one-support orthostatic posture (pose of an antique statue) with little or no participation of the abductor muscle, the movement of the hip joint in the frontal plane is that of a third-class lever analogue. If we assume that the lever of the body weight exceeds threefold the lever of the ligamentum capitis femoris reaction force, the ligamentum capitis femoris reaction force is equal to three times the weight of the body. The resultant upward force acting on the lower head of femur is equal to two times the weight of the body.
Conclusion
1. We
established experimentally that the ligamentum capitis femoris constrains
adduction and lateral and cranial displacement of the head of femur and can
locking the hip joint in the frontal plane, which is equivalent to the
transformation of this structure into an analogue of a third-class lever.
2. In the
unstrained type of the one-support orthostatic posture, when the frontal
locking of the hip joint is carried out, including through the ligamentum
capitis femoris, the group of abductor muscle can be unloaded. In this case,
the resultant load on the head of femur, being approximately equal to twice the
body weight. This load is evenly distributed between the upper and lower
hemispheres the head of femur, if a commensurate tension of the abductor muscle
group and stretching of the ligamentum capitis femoris is combined.
3.
Ligamentum capitis femoris stretching does not occur in a strained type of the
one-support orthostatic position. The hip joint is fix in the frontal plane by
tension of the abductor muscle group and its antagonists, the resultant load on
the head of femur having a downward direction, acts on the upper hemisphere and
being approximately equal to four times the body weight.
Conflict of Interest
None declared.
References
1. Adams F (1849). Hippocrates: The genuine works of Hippocrates;
translated from the Greek, with a preliminary discourse and annotations. Vol.
1, 2. Sydenham society, London.
2. Littre E (1844) Oeuvres complètes d'Hippocrate, traduction nouvelle
avec le texte grec en regard, collationné sur les manuscrits et toutes les
éditions; accompagnée d'une introduction, de commentaires médicaux, de
variantes et de notes philologiques; Suivie d'une table générale des matières,
Par É.Littré. Tome quatrieme. J.B.Baillière, Paris.
3. Cornarius I (1564). Hippocratis: Coi medicorum, omnium facile
principis Opera quae extant omnia, Jano Cornario Medico Physico interprete.
Apud Haeredes Iacobi Iunctae, Lugduni.
4. Archipov SV, Skvortsov DV (2019) Ligamentum capitis femoris: first
written mentions. MLTJ 9(2): 156–164.
5. Galenus C (1597) Galeni librorum quinta classis eam medicinae partem,
que ad Pharmaciam spectat, exponens, simplicium medicamentoru, substitutorum,
purgantium, antidotorum, componendorum tam per locos quam per genera
medicamentorum, ponderum denique, ac mensurarum doctrinam comprehendit: Septima
hac nostra editione, … Librorum numerus proximo folio continetur. Apud Iuntas,
Veneijs.
6. Cocchi A (1745) Dell'anatomia. Discorso d'Antonio Cocchi Мugellano.
Nella stamperia di Gio Batista Zannoni, Firenze.
7. Kollesch J, Kudlien F (1965) Apollonii Citiensis In Hippocratis De
articulis commentarius, ediderunt J.Kollesch et F.Kudlien, in linguam
Germanicam transtulerunt J.Kollesch et D.Nickel, Corpus Medicorum Graecorum XI
1, 1. Akademie-Verlag, Berlin.
8. Arkhipov SV (2013) Rol svyazki golovki bedrennoy kosti v patogeneze
koksartroza. Cand. Sci. (Med.)
Dissertation. Peoples’ Friendship University of Russia. Moscow.
9.
Tonkov V (1946) Anatomiya cheloveka:
Obshchaya chast': Sistema organov dvizheniya. Medgiz, Leningrad.
10. Philippon MJ, Rasmussen MT, Turnbull TL, Trindade CAC, Hamming MG et
al. (2014) Structural properties of the native ligamentum teres. Orthop J
Sports Med 2: 2325967114561962.
11. Wenger D, Miyanji F, Mahar A, Oka R (2007) The mechanical properties of the ligamentum teres: a
pilot study to assess its potential for improving stability in children’s hip
surgery. J Pediatr Orthop 27: 408–410.
12. Dehao BW, Bing TK, Young JLS (2015) Understanding the ligamentum
teres of the hip: a histological study. Acta Ortop Bras 23: 29–33.
13. O’Donnell JM, Devitt B M, Arora M (2018) The role of the ligamentum
teres in the adult hip: redundant or relevant? A review. J Hip Preserv Surg
5(1): 15-22.
14. Brady AW, Mikula JD, Chahla J, Slette E, Trindade C. et al. (2016)
Anatomic analysis of the native ligamentum teres. J Hip Preserv Surg
3(suppl_1).
15. Byrd JW (1998) Operative
Hip Arthroscopy. Thieme, New York.
16.
Neverov VA, Shil’nikov VA (1993) Sposob
fornirovaniya iskusstvennoj golovki bedra pri endoprotezirovanii. Vestn Khir 7-12: 81–83.
17.
Vorob’ev NA (1962) Svyazka golovki
bedra i yeye prakticheskoye znachenuye. In Voprosy travmatologii i ortopedii. Kiev, 157–174.
18.
Yurchak VF, Yevtushenko VA (1972) Morphological Features of the Fetal Hip Joint
in the Second Half of Pregnancy. Ortoped
Travmatol 1: 26–32.
19.
Nikolaev LN (1922) The Role of the Orbicular Ligament in the Hip Joint. Med Zh 3(1-2-3): 10–12.
20.
Ivanitskii MF (1985) Anatomiya
cheloveka s osnovami dinamicheskoy i sportivnoy morfologii: Uchebnik dlya
institutov fizicheskoy kultury. Fizkultura i Sport, Leningrad.
21.
Belen’kij VE (1962) Some Problems in Hip Joint Biomechanics. Cand. Sci. (Med.) Dissertation,
Moscow.
22.
Shapovalov VM, Shatrov NP, Tikhilolv RM, Shtilman NV (1998) The Load Pattern in
the Hip Joint in Acetabular Dysplasia and Caput Femoris Osteonecrosis. Travmatol Ortoped Ross 3: 22–26.
23.
Yanson HA (1975) Biomekhanika nizhnei
konechnosti cheloveka. Zinatne, Riga.
24.
Bombelli R (1993) Structure and
Function in Normal and Abnormal Hip: How to Rescue Mechanically Jeopardized
Hip. Springer, Berlin.
25.
Pauwels F (1965) Gesammelte Abhandlung
zur funktionellen Anatomie des Bewegungsapparates. Springer, Berlin.
26. Arkhipov SV (2009) Dynamic model
of the hip joint. Positive decision to grant a patent of the Russian Federation
on the application for the invention №2009124926A.
27. Vorob’ev VP (1932) Anatomiya cheloveka: Rukovodstvo i atlas dlya studentov i vrachej. Vol. 1. Medgiz, Moscow.
Authors & Affiliations
1. Sergey V. Arkhipov (Ph.D.)
2. Nikolay V. Zagorodny (Prof., Ph.D.)
3. Dmitry V.
Skvortsov (Prof., Ph.D.)
Corresponding author: Sergey Vasilyevich
Arkhipov
Organization: N.N. Priorov National Medical Research Center of
Traumatology and Orthopaedics, Moscow, Russia
External links
Arkhipov SV, Zagorodny NV, Skvortsov DV. Ligamentum capitis femoris a pilot an experimental study. Am J Biomed Sci & Res. 2019;5(2)92-4. DOI:10.34297/AJBSR.2019.05.000884 [researchgate.net(PDF) , biomedgrid.com]
Keywords
ligamentum capitis femoris, ligamentum teres, ligament of head of femur, abductor muscle group, hip joint, model, biomechanics
.
NB! The first publication did not contain an image of the model.
EXPERIMENTS AND OBSERVATIONS
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