Morphological Plasticity in the Talus

NewsBot · Aug 17, 2006

Members do not see these Ads. Sign Up.
Morphological Plasticity in the Juvenile Talus
C.A. Hellier, and N. Jefferya,
Foot and Ankle Surgery Volume 12, Issue 3 , 2006, Pages 139-147

Background
Little is know about the effects of the changing body weight on the juvenile skeleton and to what extent it can explain the phenotypic variability observed in human joint morphology. The talus occupies a pivotal position and must sustain and distribute the weight of the body without deformation and whilst remaining a functional biomechanical unit. It is hypothesized that the talus exhibits morphological plasticity of its articular surfaces in order to adapt to the increases in body weight associated loading over ontogeny.

Objectives
To explore plasticity in talar articular facet morphology during development in response to increases in body weight.

Method
Tali from juvenile archaeological remains from 8 to 18 years of age were cast, then laser scanned and homologous landmark data were acquired by a novel method and utilized in 3D geometric morphometric analysis. Femur length was used as a proxy for individual body weights.

Results
Changes in shape and orientation of three talar articular facets was observed over ontogeny. Principle components 1, 2, 3 and 5 correlated significantly with increases in body weight.

Conclusions
Talar articular surface morphology is plastically adaptive to changes in body weight over ontogeny. A framework of normal ontogenetic changes over the juvenile period is provided for practitioners.
Click to expand...

NewsBot · Jan 15, 2013

Non-metrical study of the pattern of talar articular facets in south Indian dry calcanei.
Sharada R, Sneha K, Gupta C, Pai SR, Rairam GB.
Surg Radiol Anat. 2012 Aug;34(6):487-91.

OBJECTIVE:
Tarsal coalitions are common in the middle talocalcaneal joints and prognosis of intracapsular fractures in the region is bad. So this study was done to know the size, shape and number of talar articular facets and the distance between the two anterior facets.

MATERIALS AND METHODS:
A total of 300 (154 right and 146 left) dry human calcanei of unknown sex were studied. The articular facets were marked with marker pen; the distance between the smaller anterior and middle facets was measured using a vernier calipers and they are classified into four types.

RESULTS:
After classification of the calcanei, we found that Type-1 was 67%, Type-2 was 28.66%, Type-3 was 3%, and Type-4 was 1.33%.

CONCLUSION:
In our study, Type-1 was common followed by Type-2. Race appears to play a part in the determination of the type of facets and hence this study will be useful for the orthopedics surgeons during various surgical procedures.
Click to expand...

NewsBot · Jun 11, 2013

Study of patterns of talar articular facets of human calcanei and their clinical implications in population of Rajasthan
Rohin Garg, Neha Dagal, Santosh Kumar, Sushila Shekhawat.
Indian Journal of Basic & Applied Medical Research; June 2013: Issue-7, Vol.-2, P. 643-650

Introduction:
There are three facets over upper side of talocalcaneal joint: anterior talar facet, middle and posterior. There is considerable variations in the number and arrangement of these facets. Present study was done to determine patterns of the talar facets of calcanei & their clinical implications in the population of Rajasthan and to find out association of patterns of the talar facets of calcanei with racial factors, if any.

Materials & methods:
310 adult dry calcaneal bones at SMS Medical College, Jaipur (Rajasthan) were studied. Each
calcaneum was carefully examined for various patterns of articulating facets for talus. Where the anterior and middle facets were separated from each other (Pattern II), the distance between the two was measured.

Results:
Pattern I with fused middle & anterior facets was predominant- found in 72.26%, followed by Pattern II in 24.52% of the bones. Pattern III, IV and V were found in 1.3%, 1.6% and 0.32% respectively. Subtypes in Pattern II: Subtype A with middle and anterior facet separation of (<2mm)-4.8%, Subtype B (2-5mm)-7.7%, Subtype C (>5 mm)-8.1%.

Conclusion:
The articular facets of subtalar joint on calcanei show racial and individual differences. Study population may be at greater risk of developing subtalar arthritis due to predominant pattern I calcanei as compared to the Europeans who present pattern II commonly. This fact necessitates
modifications of the western surgical techniques to suit the Indian scenario especially for orthopaedic surgeons in India when they perform calcaneal osteotomy.
Click to expand...

NewsBot · Aug 9, 2013

Study of Variations in Pattern of Calcaneal Articular Facets in Human Tali in the Population of Rajasthan (India).
R. Garg, S. Babuta, K. Mogra, R. Parashar, S. Shekhawat
People's Journal of Scientific Research Year : 2013 | Volume :6 | Issue : 2 | Page : 19-23

Talus (astragalus) is the second largest tarsal bone. It has no muscular or tendinous attachment. It takes part in
the formation of various articulations in the form of talocrural , talocalcaneonavicular or subtalar joints. The prior knowledge
of the anatomical set of talus and its various articulations holds significance in operating procedures. Knowing anatomy
of talus not only helps in delineating underlying pathology but also helps in treatment. Three hundred dry adult tali (150-
right and 150-left) were studied. Each talus was examined for the presence of various patterns of articular facets. They were
classified into five groups. Type I was found in 39% cases. Type II in 43.7% cases, Type III in 6% cases, Type IV in 5.3%
cases and Type V was in 6% cases; type V has two subtypes. Subtype ‘A’ was found in 5% cases & subtype ‘B’ was found
in 1% cases. In the present study, highest incidence of type II tali was 43.7 % and type IV had lowest incidence of 5.3%.
These variations and their incidences can be used as an anthropological marker for racial and regional differences in
unidentified bones. Further, studies on various other population is indicated using larger sample size to make comparative
studies more meaningful.
Click to expand...

NewsBot · May 10, 2014

Symmetry analysis of talus bone
A Geometric morphometric approach
K. Islam et al
Bone Joint Res 2014;3:139–45.

The main object of this study was to use a geometric morphometric approach to quantify the left-right symmetry of talus bones.

Methods Analysis was carried out using CT scan images of 11 pairs of intact tali. Two important geometric parameters, volume and surface area, were quantified for left and right talus bones. The geometric shape variations between the right and left talus bones were also measured using deviation analysis. Furthermore, location of asymmetry in the geometric shapes were identified.

Results Numerical results showed that talus bones are bilaterally symmetrical in nature, and the difference between the surface area of the left and right talus bones was less than 7.5%. Similarly, the difference in the volume of both bones was less than 7.5%. Results of the three-dimensional (3D) deviation analyses demonstrated the mean deviation between left and right talus bones were in the range of -0.74 mm to 0.62 mm. It was observed that in eight of 11 subjects, the deviation in symmetry occurred in regions that are clinically less important during talus surgery.

Conclusions We conclude that left and right talus bones of intact human ankle joints show a strong degree of symmetry. The results of this study may have significance with respect to talus surgery, and in investigating traumatic talus injury where the geometric shape of the contralateral talus can be used as control.
Click to expand...

NewsBot · May 22, 2014

Patterns of talar articulating facets in adult human calcanei from North-East India and their clinical correlation
K. Anjaneyulu, Chandra Philips, Binod K. Tamang, Arun Kumar
Asian Journal of Medical Sciences | Oct-Dec 2014 | Vol 5 | Issue 4

Calcaneus is the largest tarsal bone of the foot and forms the posterior prominence of the heel. The calcaneus articulates with the talus superiorly at the subtalar joint. The subtalar joint is responsible for the inversion and eversion. There are three facets over upper side of talocalcaneal joint: anterior talar facet, middle and posterior. There are considerable variations in the number and arrangement of these facets. A total of 100 dry adult human calcanei were obtained irrespective of age and sex and evaluated for the pattern of talar articulating facets and measurements were made with digital vernier calliper of 0.01 mm accuracy at anatomy laboratory of Sikkim Manipal Institute of Medical Sciences, Sikkim. The study revealed that type-A was 31%, type-B was 5%, type-C was 62% and type-D was 2%. In our study type-C was followed by type-A. These morphological variations on the superior surface of the sustentaculum tali may predispose people to joint instability, ligamentous laxity and the development of arthritic changes in the subtalar joint.
Click to expand...

NewsBot · Jul 12, 2014

Subtalar Joint Configuration on Weightbearing CT Scan
Fabrice Colin et al
Foot & Ankle International July 11, 2014

Background: Standard values that describe the morphology of the subtalar (ST) joint have previously been obtained from cadaveric studies or by using conventional unloaded radiographs. It is known that these parameters differ significantly from those measured in vivo and in loaded images, limiting the diagnostic value of the previously published morphological parameters in the literature. However, the morphology of the ST joint clearly affects its function. The objective of this study was to determine the morphology of the posterior facet of the ST joint using loaded computed tomography (CT) images and to describe the different configurations found in asymptomatic patients.
Methods: A weightbearing CT scan was performed on 59 patients without any history of hindfoot and ankle pathology. The shape of the posterior facet and the subtalar vertical angle (SVA) were measured in 3 different coronal planes of the ST joint.
Results: The posterior facet was concave in 88% and flat in 12%. The posterior facet was oriented in valgus in 90% and varus in 10% when measured in the middle coronal plane. However, the SVA changed depending on which coronal plane it was measured in.
Conclusion: We believe it is important to get a better insight into the morphological parameters of the ST joint.
Clinical Relevance: Knowledge of subtalar joint morphology could help clarify why certain failures have occurred in reconstructive hindfoot surgery and thus might help plan the surgical procedure to reduce these failures in the future.
Click to expand...

Rob Kidd · Jul 12, 2014

Cause of, or caused by, that is the question. To which these guys do not even try to provide an answer.

Greg Quinn · Jul 12, 2014

Good point Rob. It seems to be a matter of unpicking variance in population genetics, epistasis and the regulation of adaptive plasticity through mechanotransduction from the environment.

While there is nothing surprising in these papers, it's only by understanding the science behind the findings that will ever lead to an understanding of why attempting to acheive STJ Neutral positioning in orthoses is biological nonsense!

NewsBot · Oct 4, 2014

Anatomical characteristics of the accessory antero-lateral talar facet.
Hirano T, Niki H, Akiyama Y, Beppu M.
J Orthop Sci. 2014 Oct 3

BACKGROUND:
We examined the anatomical features of the accessory antero-lateral talar facet (AALTF) in adults.
METHODS:
The sample comprised 44 feet (male: 10 cadavers and 20 feet; female: 12 cadavers and 24 feet) obtained from 22 cadavers used for systemic autopsy. The mean age was 86.5 years. The talus and calcaneus were obtained from the autopsy cadavers, and the soft tissue was surgically removed from the bone. The talus and calcaneus were then separated and their anatomical features were observed.
RESULTS:
The AALTF was identified in 11 of 44 (25 %) feet. The presence or absence of the AALTF and calcaneal facet opposing the AALTF were classified into four groups: (1) joint type with articular cartilage on both the talus and calcaneus; (2) talar type with articular cartilage on the talus only; (3) calcaneal type with articular cartilage on the calcaneus only; and (4) non-joint type with no articular cartilage on either the talus or calcaneus.
CONCLUSIONS:
When the AALTF is present, the talus comes into contact with the calcaneus, and thus even slight changes around the talus and calcaneus can easily cause impingement.
Click to expand...

Admin2 · Oct 4, 2014

NewsBot said: ↑

CONCLUSIONS:
When the AALTF is present, the talus comes into contact with the calcaneus, and thus even slight changes around the talus and calcaneus can easily cause impingement.
Click to expand...

see:
Accessory Talar Facet Impingement

NewsBot · Jan 3, 2015

Morphometric analyses of human dry tali of South Indian origin
Manjunath V Motagi, Sugathan R Kottapurath, Kavitarati Dharwadkar.
Int J Med Sci Public Health. 2015; 4(2): -doi: 10.5455/ijmsph.2015.3009201443

Background: Talus is the key bone of the human body as it carries the whole weight of the body. Since the talus endures a lot of differential forces during locomotion, the stress patterns across the talus influence its overall dimensions. Research in skeletal biology and methodological approaches to the identification of human skeletal remains have advanced significantly in recent years. This study was undertaken because of the scarcity of the morphometric data in adult human dry tali of South Indian origin.

Objectives: The objectives of this study were to estimate the angles of declination and inclination in adult human dry tali; to estimate the differences in the angles between right and left tali; and to report and estimate the differences in other morphological parameters such as maximum anterioposterior length of the talus, maximum transverse width of the talus, trochlear length, length of the sulcus tali, and width of the sulcus tali of right and left sides.

Materials and Methods: The study was carried out on 50 (25 right and 25 left) adult dry tali of unknown ages and sexes over a period of 6 months in the Department of Anatomy, Amala Institute of Medical Sciences. The angles of declination and inclination were measured with goniometer. Other parameters were measured with digital Vernier calipers.

Results: The mean angles of declination were 26° and 27° and those of inclination were 120° and 122° on the right and left sides, respectively. All the parameters measured showed no statistically significant difference between the right and left sides.

Conclusion: The values of this study were relatively closer to the other studies. The parameters of this study may be helpful to surgeons, orthopedicians, and forensic anthropologists.
Click to expand...

NewsBot · Feb 18, 2015

Evolution of postural diversity in primates as reflected by the size and shape of the medial tibial facet of the talus.
Boyer DM, Yapuncich GS, Butler JE, Dunn RH, Seiffert ER.
Am J Phys Anthropol. 2015 Feb 14. doi: 10.1002/ajpa.22702.

OBJECTIVES:
Comprehensive quantification of the shape and proportions of the medial tibial facet (MTF) of the talus (=astragalus) has been lacking for Primates and their closest relatives. In this study, aspects of MTF form were quantified and employed to test hypotheses about their functional and phylogenetic significance. The following hypotheses influence perceptions of primate evolutionary history but are due for more rigorous assessment: 1) A relatively large MTF distinguishes "prosimians" (strepsirrhines and tarsiers) from anthropoids and non-primate euarchontans; 2) the distinctive form of the "prosimian" MTF is a correlate of locomotor tendencies that emphasize use of vertical and small diameter supports in conjunction with inverted, abducted foot postures; and 3) the "prosimian" MTF form arose along the primate stem lineage and was present in the euprimate common ancestor.
METHODS:
Three-dimensional (3D) scanning was used to create scale digital models of tali (n = 378 specimens, 122 species) from which three types of variables capturing aspects of MTF form were computed: 1) MTF area relative to body mass and ectal facet area; 2) MTF shape (elliptical vs. non-elliptical); and 3) MTF dorsal restriction on the talar body (i.e., extensive vs. minimal exposure of non-articular area). Data were analyzed using both phylogenetic and traditional comparative methods including Phylogenetic Generalized Least Squares, Ordinary Least Squares, ANCOVA, ANOVA, and Bayesian Ancestral State Reconstruction (ASR).
RESULTS:
Extant "prosimians" are generally distinct from anthropoids and non-primate euarchontans in our quantitative representations of MTF form. MTF area (but not shape or dorsal restriction) correlates with fibular facet angle (FFa) of the talus, which has also been argued to reflect habitual pedal inversion. Among strepsirrhines, taxa that engage in grasp-leaping more frequently/effectively appear to have a relatively larger MTF than less acrobatic taxa. Directional models of evolutionary change better describe the phylogenetic distribution of MTF variation than do other models. ASR shows 1) little change in the MTF along the primate stem, 2) independent evolution of relatively large and dorsoplantarly deep MTFs in basal haplorhines and strepsirrhines, and 3) re-evolution of morphologies similar to non-euprimates in anthropoids.
CONCLUSIONS:
Results support the hypothesis that differences in MTF form between anthropoids and "prosimians" reflect greater use of inverted foot postures and grasp-leaping in the latter group. Although fossil "prosimians" do not have the extreme MTF dimensions that characterize many extant acrobatic leapers, these variables by themselves provide little additional behavioral resolution at the level of individual fossils due to strong phylogenetic signal. ASR suggests that some specialization for use of inverted foot postures (as required in a fine-branch niche) and modifications for grasp-leaping evolved independently in basal strepsirrhine and haplorhine lineages
Click to expand...

NewsBot · Aug 11, 2022

Human talar ontogeny: Insights from morphological and
trabecular changes during postnatal growth
Carla Figus et al
Am J Biol Anthropol. 2022;1–18

Objectives: The study of the development of human bipedalism can provide a unique
perspective on the evolution of morphology and behavior across species. To generate
new knowledge of these mechanisms, we analyze changes in both internal and external morphology of the growing human talus in a sample of modern human juveniles
using an innovative approach.
Materials and Methods: The sample consists of high-resolution microCT scans of
70 modern juvenile tali, aged between 8 postnatal weeks and 10 years old, from a
broad chronological range from Middle/Late Neolithic, that is, between 4800 and
4500 BCE, to the 20th century. We applied geometric morphometric and whole-bone
trabecular analysis (bone volume fraction, degree of anisotropy, trabecular number,
thickness, and spacing) to all specimens to identify changes in the external and internal morphology during growth. Morphometric maps were also generated.
Results: During the first year of life, the talus has an immature and globular shape,
with a dense, compact, and rather isotropic trabecular architecture, with numerous
trabeculae packed closely together. This pattern changes while children acquire a
more mature gait, and the talus tends to have a lower bone volume fraction, a higher
anisotropy, and a more mature shape.
Discussion: The changes in talar internal and external morphologies reflect the different loading patterns experienced during growth, gradually shifting from an “unspecialized” morphology to a more complex one, following the development of bipedal gait.
Our research shows that talar plasticity, even though genetically driven, may show
mechanical influences and contribute to tracking the main locomotor milestones.
Click to expand...

NewsBot The Admin that posts the news.

NewsBot The Admin that posts the news.

NewsBot The Admin that posts the news.

NewsBot The Admin that posts the news.

NewsBot The Admin that posts the news.

NewsBot The Admin that posts the news.

NewsBot The Admin that posts the news.

Rob Kidd Well-Known Member

Greg Quinn Active Member

NewsBot The Admin that posts the news.

Admin2 Administrator Staff Member

NewsBot The Admin that posts the news.

NewsBot The Admin that posts the news.

NewsBot The Admin that posts the news.

Foot morphological between ethnic groups

Asymmetry of Achilles tendon mechanical and morphological properties between both legs

The Ankle Retinacula: Morphological Evidence of the Proprioceptive Role of the Fascial System

Morphological adaptation of the tarso-metatarsal joints onto load transmission in the foot

Maladaptive Neuroplasticity in Corticospinal Tract after Ankle Sprain

Mechanobiology and Adaptive Plasticity (MAP) Theory and Foot Function

Neuroplasticity example

Share This Page