How the Skeletal System Works

Your bones are your body’s building blocks, the structure around which all other body parts form. Ligaments attach your bones to each other and tendons attach your bones to your muscles. Joints and cartilage allow for bending and shock absorbency.

Moving Your Joints

Your bones are connected and move together, but they are not directly touching each other. All of your bending movement takes place where there is a joint. There are many types of joints that allow for different types of movement. For example, your knees and elbows bend in only one direction, while your wrists and ankles allow for a wider range of movement. Together these tissues give you mobility and allow you to sustain the activities you want to perform.

Healing a Broken Bone

If you have ever had broken a bone, you probably had it diagnosed with an x-ray. The doctor may have had to set the break or realign the broken bone to its correct orientation so it would heal correctly. What happens after the doctor has done his/her job? How does your body complete the bone healing process?

Phase 1

When a bone breaks, your body’s first task is to stop the internal bleeding.  Blood vessels constrict and a blood clot forms at the break site. Then, immune cells move to the injured site to form a type of connective tissue that covers up blood clots.

Phase 2

Within a few days, the periosteum begins to grow by forming osteoblasts that make new bone. The periosteum also creates new cartilage cells that sit between bones. The new bone forms until it fills the gap left by the break. At this point, new blood vessels grow through the bone. Finally, spongy bone replaces the new bone.

Phase 3

In the final phase of bone healing, osteoclasts resorb the spongy bone and osteoblasts replace it with compact bone, returning the bone’s strength. The osteoclasts also help remodel the bone to its original shape.