Long bones are shafts with ‘heads’ on both sides. Our limbs contain mostly long bones. Short bones Complete Labeled Skeleton are cubular, and mostly comprised of spongy bone. Wrist and ankle bones are short bones (www2.highlands.edu, The Skeletal System:Macro and Micro Anatomy). Flat bones are usually curved and sandwich spongy bone between two layers of compact bone.
A hollow medullary cavity is found in the center of the long bones and serves as a storage are for the bone marrow. Examples: Femur and Tibia, Etc. Short bones are about the same size long and wide. The carpal bone of the wrist and the tarsal bones of the bones of the foot are the short bones in the body. The flat bones in the body vary in size and shape but have a common feature of being very thin in one direction.
This cell is known as a chondrocyte. It is a cell found in healthy cartilage which is a part of the skeletal system. The skeletal system is mainly made up of bones. These bones support the body. Without them, the skeleton would have no structure, just a gooey mass of tissues.
In the femur, cancellous bone mainly distributes in upper extremity and lower extremity while cortical bone consist mainly the middle shaft bone. Femur bone is light and strong which is hardly bro- ken in static state. However in many high speed impact situations femur is likely broken. The FEA(finite element analysis) method helps apply different kinds of load and force on to the femur model and reveal detail information of it. !
The growth of bones in width or diameter is called appositional growth. In this process, osteoblasts deposit new tissue on the inside of the periosteum which calcifies. At the same time, osteoclasts dissolve the surface of the inner bone, widening the medullary cavity. This simultaneous building and destroying of bones cells is called bone remodeling. Mineral deposition is the deposit of calcium, phosphate and other ions into bone tissue through blood plasma.
Ossification is characterized as a process that produces new bone. This process is also known as bone formation. Bone formation consists of two types of development. They are intramembranous and endochondral formation. Intramembranous ossification takes place when cells within the membrane change and become osteochondral progenitor cells.
Bone shapes The shapes of the bones reflect their functions. Long bones act as leavers to raise and lower; short bones, such as the ankle bones (talus) are useful bridges; flat bones including those found in the skull form protective shells. Small, rounded, sesamoid bones, such as the knee cap (patella), are embedded within tendons. Irregular bones include vertebrae, the pelvis (ilium), and some skull bones, such as the sphenoid. Bones of the hand and foot The skeletal structure of the hand and foot is similar; in both cases there is an interlinking arrangement of small bones.
As the matrix hardens, it forms lamella, a tube of the solidified bone matrix, which forms the lamellar bone. Essentially, lamellar bone is lamellae with collagen fibers surrounding each lamella. It is important to know that collagen fibers on one layer, run parallel to the collagen fibers on another layer. For this reason, lamellar bone is very tough. The lamellar bone is located on both sides of the spongy bone and thickens around the trabeculae.
Humerus The humerus is the long bone in the upper arm. It is located between the elbow joint and the shoulder. At the elbow, it connects primarily to the ulna, as the forearm's radial bone connects to the wrist.
SKELETON OF HAND The hand’s skeleton has three regions. 1) Carpal 2) Metacarpal 3) Phalanges 1) Carpal The Proximal row contains (lateral to medial side)- i) SCAPHOID ii) LUNATE iii) TRIQUETRAL iv) PISIFORM The distal row contains in same order- i) TRAPEZIUM ii) TRAPEZOID iii) CAPITATE iv) HAMATE. The proximal row is convex proximally, and concave distally. The distal row is convex proximally and flat distally. Each bone has 6 surfaces- Palmar, dorsal, lateral, medial, proximal, distal.