Skeletal System

 

Skeletal systems main constitute is bone; rigid structures of calcified dense connective tissue containing three fundamental cells:

  • osteoblasts for creating new bone tissue.
  • osteoclasts for upcycle of tissue.
  • osteocytes, used for maintaining bone structure.

(Florencio-Silva, et al., 2015)

 

Long

  • Tubular shaped
  • Longitudinal
  • Smaller diameter
  • Thick cortex
  • Osteons containing nerves and blood vessels
  • Shock absorbing trabeculae 

Short

  • Cuboidal
  • Shock absorbing trabeculae
  • Thin cortical outer layer

Flat

  • Thin
  • Flattened
  • Typically curved
  • Two parallel cortical bone layers

Sesamoid
  • Small (<1cm) 
  • Rounded/ovalized
  • Embedded within tendons
  • Shock absorbing trabeculae
  • Thin cortical outer layer
  • Connective periosteum 
    (Anatomy Team, 2025)

Irregular
  • Shock absorbing trabeculae
  • Thin cortical outer layer
  • Foramina- Allowing neurovascular structures and blood vessels through tissues (Sendic, 2023).

Axial skeleton - The central anatomical core consisting of the skull, vertebral column and thorax.

Appendicular skeleton - The shoulder and pelvic girdle, inclusive of upper and lower limbs (theskeletalsystem, n.d.).

 

Joints

 

Fibrous

  • Attached by dense fibrous connective tissue, predominantly collagen
  • Immovable, providing rigidity in critical areas
  • Lack of cavity

Cartilaginous

  • Tether bones with cartilage, reducing friction, supporting shock absorption
  • Limited movement
  • Lack of cavity
  • Divided into synchondrosis and symphysis joints (Byju's, n.d.).

     

  Synovial 

  • Mobile
  • Joint cavity containing synovial fluid secreted by the synovial membrane (lines articular capsules)
  • Hyaline cartilage forms the articular cartilage, covering the whole articulating surface of each bone

Dependant on anatomical position, and function of articulating surface, synovial joints can be divided into ball and socket, condyloid, hinge, pivot, saddle and plane (Quinn, 2024).

Connective Tissues

Cartlidge is tough and flexible, composed of collagen and chondrocytes, supporting shock absorption and friction reduction. (Sendic, 2023).

 

Ligaments are tough, fibrous tissues connecting bones together in proper articulation at the joints, supporting muscular-skeletal stability. Composed of elastin and collagen, providing strength and elasticity.  (Cleveland clinic, 2025).

 

Tendons are strong, fibrous and viscoelastic. Composed of elastin, collagen and fibroblast, connecting muscle to bone, creating muscular tension, enabling movement. They contain nerves and blood vessels for tissue repair, however, limited blood flow (Bailey, 2022).