Organization of the Cartilaginous Texture.
The cartilages, when they are divided, seem to be homogeneous, and without any appearance of fibers, vessels, or nerves; but when they are carefully prepared, a fibrous texture becomes apparent, and the phenomena which they exhibit in health and disease prove the existence of a vascular and nervous structure. The proper cartilaginous texture consists of an immense number of whitish fibers, which can be seen in the articular cartilage after it has been macerated during six months; they are also rendered apparent by boiling, provided it be not prolonged so far as to cause a solution of the animal matter. These fibers, which pass in a direction perpendicular to the bone, are distinguished by their great firmness, which is inferior only to that of the osseous structure; they are also highly elastic, and at the same time so brittle, that if they are forcibly bent, they give way and break.
The tissue of the costal cartilages is very obscure, and at first sight homogeneous; but these bodies, after a prolonged maceration, separate into oval layers or plates, which are united by oblique fibers which reciprocally from one to the other; these laminae themselves composed of radiating fibers.
The cellular tissue of the cartilage, owing to its extreme condensation, is with difficulty distinguished: it can, in fact, only be seen after a prolonged maceration, or the action of boiling water has reduced the cartilage into a soft and cellular substance. The arteries are so extremely minute that they do not receive red blood; a colorless and nutritive fluid circulates, however, in the cartilage, although some writers have contended that it is a non-vascular structure. The existence of vessels is satisfactorily proved by the deposition of new particles during growth, and by the yellow colour which those bodies assume in jaundice.* Lymphatics cannot be detected, but their presence is rendered evident by the absorption that takes place in cartilage in the process of ossification, and also in many diseases. It has been remarked that the power of the absorbents is greater in the osseous than in the cartilaginous, or rather in the fibro-cartilaginous texture, t These organs, in their healthy state, are not endowed with sensibility, but as they become painful in inflammation, we must conclude that they receive nerves, although they cannot be traced by the eye.
The chemical composition of cartilage has been carefully examined, especially in this country. It was stated by Haller, that it consisted of gelatine and earth; but the investigations of Mr. Hatchett and Dr. Davy prove that there is little, if any, jelly. These chemists conclude that cartilage is principally composed of condensed albumen, and the latter also has detected a small portion of earthy phosphate. The following is the analysis of Dr. Davy: — Albumen, 445; water, 550; phosphat- of lime, -fi = 1004 By the continued action of boiling water most of the cartilages may be dissolved; they are also readily dissolved by nitric acid, and by a strong solution of potash. When a piece of cartilage is dried, it becomes yellow, semi-transparent, and very brittle; if it is then placed in water, it regains in a few days its white colour, opacity, and flexibility.
- Blaetner, Kirch. Gen. ii. p. 238. t Brodie, L c. p. 301.
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Properties and Uses.
Key Takeaways
- Cartilages exhibit a fibrous texture when carefully prepared, which is highly elastic but brittle.
- The tissue of costal cartilages separates into layers connected by oblique fibers.
- Arteries in cartilage are extremely minute and do not receive red blood.
Practical Tips
- Careful preparation techniques can reveal the fibrous texture within cartilage, aiding in medical studies.
- Understanding the structure of costal cartilages helps in diagnosing conditions like rib fractures.
Warnings & Risks
- Forcing a bend on cartilage fibers may cause them to break due to their brittle nature.
- The chemical composition of cartilage can be altered by prolonged exposure to boiling water, affecting its properties.
Modern Application
While the detailed anatomical descriptions and preparation methods from this chapter are foundational for medical science, modern survival preparedness focuses more on practical applications. Understanding the structure and resilience of cartilage is still relevant in assessing injuries or conditions involving joints and ribs.
Frequently Asked Questions
Q: What happens to cartilage fibers when they are forcibly bent?
Cartilage fibers become brittle if forcibly bent, leading them to break due to their high elasticity but low tensile strength.
Q: How can one detect the fibrous texture of cartilage?
Pro Technique
Careful preparation techniques such as maceration or boiling (without dissolving) can reveal the fibrous texture within cartilage.
Q: What is the chemical composition of cartilage according to Dr. Davy's analysis?
Dr. Davy's analysis shows that cartilage consists mainly of condensed albumen (445), water (550), and a small portion of earthy phosphate (-fi = 1004).