The thoracic wall and diaphragm
Peter Abrahams, John Craven, John Lumley in Illustrated Clinical Anatomy, 2011
This readily palpable protuberance is an important landmark: here the 2nd costal cartilage articulates on the same plane as the 4th thoracic vertebra, the bifurcation of the trachea, and the beginning and end of the aortic arch. The body of the sternum is some 10 cm long and articulates on its lateral borders with the 2nd to the 7th costal cartilages. Behind the body lie the heart valves, in the order from above downwards PAMT (pulmonary, aortic, mitral and tricuspid: see Fig. 2.1b, p. 35). The narrow lower end articulates with the xiphoid cartilage, which is cartilaginous in early life and gives attachment to the diaphragm and rectus abdominis.
SECTION 3 THE TRUNK
Bassel Zebian, Wayne Lam, Rishi Aggarwal in One Stop Doc Musculoskeletal System, 2005
The thoracic cage includes the 12 pairs of ribs articulating posteriorly with the vertebral column and the sternum. The sternum is divided into three parts: the manubrium (superiorly), the body and the xiphoid process (inferiorly). True ribs are the first seven as they are attached directly to the sternum by their own costal cartilages. False ribs (8-10 inclusive) indirectly articulate with the sternum, as their costal cartilage is combined with that of the rib above. Ribs 11 and 12 do not articulate with the sternum and hence are termed floating ribs.
3 Pectoralis major
John Langdon, Mohan Patel, Peter Brennan in Operative Oral and Maxillofacial Surgery Second edition, 2011
First described by Ayrian in 1979, the pectoralis major rapidly became the workhorse in head and neck reconstruction. Raised as either a myocutaneous or muscle flap, only the flap developed a reputation for a reliable easyto-use reconstruction. It is based on vessels of the thoracromial artery. The muscle exists as two portions: a clavicular head, from its sternal half, and a sternocostal head, from the sternum to the level of the seventh costal cartilage, and from the upper sixth ribs. The muscle is attached by a flat tendon into the lateral lip of the intertubercular sulcus of the humerus.
The effect of calcification on the structural mechanics of the costal cartilage
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2014
Jason L. Forman, Richard W. Kent
The costal cartilage often undergoes progressive calcification with age. This study sought to investigate the effects of calcification on the structural mechanics of whole costal cartilage segments. Models were developed for five costal cartilage specimens, including representations of the cartilage, the perichondrium, calcification, and segments of the rib and sternum. The material properties of the cartilage were determined through indentation testing; the properties of the perichondrium were determined through optimisation against structural experiments. The calcified regions were then expanded or shrunk to develop five different sensitivity analysis models for each. Increasing the relative volume of calcification from 0% to 24% of the cartilage volume increased the stiffness of the costal cartilage segments by a factor of 2.3–3.8. These results suggest that calcification may have a substantial effect on the stiffness of the costal cartilage which should be considered when modelling the chest, especially if age is a factor.
Costal cartilage graft with perichondrium, a possible anti-adhesive material
Published in Journal of Plastic Surgery and Hand Surgery, 2017
Norio Fukuda, Hirotaka Asato, Kohei Umekawa, Goro Takada, Takeshi Kan, Shoichi Sasaki
Background: Adhesion occurs as a part of the wound healing process, but it sometimes compromises patients’ daily activities. The authors were looking for materials and methods that could prevent adhesion, and noticed that the costal cartilage has possibility. The anti-adhesive property of the costal cartilage was examined histologically. Methods: Thirty-five patients with microtia who provided consent for participating in this study were enrolled between April 2008 and March 2015. In the first stage of microtia reconstruction surgery, the excess cartilage was used to create these three types of specimens: (A) a piece of cartilage retaining the perichondrium on one side, (B) a piece of only cartilage parenchyma sliced with a plane parallel to the long axis of costal cartilage, and (C) the costal cartilage in a plane perpendicular to the long axis sliced pieces. These specimens were implanted into the subcutaneous fat of the chest. After at least 6 months in the second stage of surgery (i.e. auricular elevation), these specimens, wearing a little around the adipose tissue, we removed and examined histologically. Result: A fibrosis formation of the perichondrium side of Specimen A was thicker significantly than that of the cartilage side. A fibrosis formation of Specimen B was thicker significantly than that of the cartilage side of Specimen A. Conclusion: It was suggested that, if there is perichondrium, the costal cartilage parenchyma surface makes less adhesion with surrounding tissues. Costal cartilage with unilateral perichondrium is likely to be an effective surgical material for adhesion prevention.
A Pseudo-Elastic Effective Material Property Representation of the Costal Cartilage for Use in Finite Element Models of the Whole Human Body
Published in Traffic Injury Prevention, 2010
Jason Forman, Eduardo de Dios, Richard Kent
Objective: Injury-predictive finite element (FE) models of the chest must reproduce the structural coupling behavior of the costal cartilage accurately. Gross heterogeneities (the perichondrium and calcifications) may cause models developed based on local material properties to erroneously predict the structural behavior of cartilage segments. This study sought to determine the pseudo-elastic effective material properties required to reproduce the structural behavior of the costal cartilage under loading similar to what might occur in a frontal automobile collision. Methods: Twenty-eight segments of cadaveric costal cartilage were subjected to cantilever-like, dynamic loading. Three limited-mesh FE models were then developed for each specimen, having element sizes of 10 mm (typical of current whole-body FE models), 3 mm, and 2 mm. The cartilage was represented as a homogeneous, isotropic, linear elastic material. The elastic moduli of the cartilage models were optimized to fit the anterior–posterior (x-axis) force versus displacement responses observed in the experiments. For a subset of specimens, additional model validation tests were performed under a second boundary condition. Results: The pseudo-elastic effective moduli ranged from 4.8 to 49 MPa, with an average and standard deviation of 22 ± 13.6 MPa. The models were limited in their ability to reproduce the lateral (y-axis) force responses observed in the experiments. The prediction of the x-axis and y-axis forces in the second boundary condition varied. Neither the effective moduli nor the model fit were significantly affected (Student's t-test, p < 0.05) by the model mesh density. The average pseudo-elastic effective moduli were significantly (p < 0.05) greater than local costal cartilage modulus values reported in the literature. Conclusions: These results are consistent with the presence of stiffening heterogeneities within the costal cartilage structure. These effective modulus values may provide guidance for the representation of the costal cartilage in whole-body FE models where these heterogeneities cannot be modeled distinctly.