woven bone

Examples of woven bone in the following topics:

• Microscopic Anatomy of Bone

  • The basic microscopic unit of bone is an osteon, which can be arranged into woven bone or lamellar bone.
  • Osteons can be arranged into woven bone or lamellar bone.
  • Woven bone is replaced by lamellar bone during development.
  • After a fracture, woven bone forms initially, but it is gradually replaced by lamellar bone during a process known as bony substitution.
  • Woven bone is characterized by the irregular organization of collagen fibers and is mechanically weak.

• Bone Repair

  • The periosteal cells distal to (further from) the fracture gap develop into osteoblasts that form woven bone.
  • Eventually, the fracture gap is bridged by the hyaline cartilage and woven bone, restoring some of its original strength.
  • The next phase is the replacement of the hyaline cartilage and woven bone with lamellar bone.
  • Substitution of the woven bone with lamellar bone precedes the substitution of the hyaline cartilage with lamellar bone.
  • Eventually, all of the woven bone and cartilage of the original fracture callus is replaced by trabecular bone, restoring most of the bone's original strength.

• Embryonic and Fetal Bone Formation

  • Much like spicules, the increasing growth of trabeculae result in interconnection, and this network is called woven bone.
  • Eventually, woven bone is replaced by lamellar bone.
  • As growth continues, trabeculae become interconnected and woven bone is formed.
  • The primary center of ossification is the area where bone growth occurs between the periosteum and the bone.
  • It is also an essential process during the rudimentary formation of long bones, the growth of the length of long bones, and the natural healing of bone fractures.

• Capacity of Different Tissues for Repair

  • The next phase is the replacement of the hyaline cartilage and woven bone with lamellar bone.
  • The replacement process is known as endochondral ossification with respect to the hyaline cartilage and bony substitution with respect to the woven bone.
  • Substitution of the woven bone with lamellar bone precedes the substitution of the hyaline cartilage with lamellar bone.
  • This new lamellar bone is in the form of trabecular bone.
  • Eventually, all of the woven bone and cartilage of the original fracture callus is replaced by trabecular bone, restoring most of the bone's original strength.

• Structural Elements of Connective Tissue

  • Collagen, in the form of elongated fibrils, is mostly found in fibrous tissues such as tendons, ligaments, and skin and is also abundant in cornea, cartilage, bone, blood vessels, the gut, and intervertebral discs.
  • In bone, entire collagen triple helices lie in a parallel, staggered array.
  • This network acts as a supporting mesh in soft tissues such as liver, bone marrow, and the tissues and organs of the lymphatic system.
  • Reticular fiber is composed of one or more types of very thin and delicately woven strands of type III collagen.

• Gross Anatomy

  • All the bones in the body can be described as long bones or flat bones.
  • Bone is made of bone tissue, a type of dense connective tissue.
  • Cortical bone is compact bone, while cancellous bone is trabecular and spongy bone.
  • The outer shell of the long bone is compact bone, below which lies a deeper layer of cancellous bone (spongy bone), as shown in the following figure.
  • These are flat bone, sutural bone, short bone, irregular, sesamoid bone, and long bone.

• Bone Grafting

  • Bone grafting is a surgical procedure that replaces missing bone in order to repair bone fractures.
  • Bone grafting is a surgical procedure that replaces missing bone in order to repair bone fractures that are extremely complex, pose a significant health risk to the patient, or fail to heal properly .
  • Bone grafts may be autologous (bone harvested from the patient's own body, often from the iliac crest), allograft (cadaveric bone usually obtained from a bone bank), or synthetic (often made of hydroxyapatite or other naturally-occurring and biocompatible substances) with similar mechanical properties to bone.
  • Most bone grafts are expected to be reabsorbed and replaced as the natural bone heals over a few months' time.
  • Bone grafting is also used to fuse joints to prevent movement, repair broken bones that have bone loss, and repair broken bone that has not yet healed.

• Tissue Engineering

  • ., bone, cartilage, blood vessels, bladder, skin, etc.).
  • These techniques include all the approaches that have been successfully employed for the preparation of non-woven meshes of different polymers.
  • In particular, non-woven polyglycolide structures have been tested for tissue engineering applications: such fibrous structures have been found useful to grow different types of cells.

• Bone Scans

  • Bone scans are a special type of nuclear scanning test that is often used to find bone cancer or bone inflammation.
  • A bone scan is a nuclear scanning test to find certain abnormalities in bone that are triggering the bone's attempts to heal.
  • A nuclear bone scan is a functional test, which means it measures an aspect of bone metabolism or bone remodeling .
  • Nuclear bone scans are not to be confused with the completely different test often termed a "bone density scan," DEXA or DXA, which is a low exposure X-ray test measuring bone density to look for osteoporosis and other diseases where bones lose mass, without any bone re-building (osteoblastic) activity.
  • The technique, therefore, is sensitive to fractures and bone reaction to infections and bone tumors, including tumor metastases to bones, because all these pathologies trigger bone osteoblast activity.

• Bone Remodeling

  • Bone remodeling or bone turnover is the process of resorption followed by replacement of bone and occurs throughout a person's life.
  • Bone volume is determined by the rates of bone formation and bone resorption.
  • Numerous bone-derived growth factors have been isolated and classified via bone cultures.
  • Essentially, bone growth factors may act as potential determinants of local bone formation.
  • Bone tissue is removed by osteoclasts, and then new bone tissue is formed by osteoblasts.