Introduction to Biomechanics IE497B Dr. R. A. Wysk

The human skeleton

Bone components

Cortical Bone

Osteonal Bone

Joints Fibrous Fibrous Fibrous joints connect bones without allowing any movement. The bones of your skull and pelvis are held together by fibrous joints. The union of the spinous processes and vertebrae are fibrous joints. Fibrous joints connect bones without allowing any movement. The bones of your skull and pelvis are held together by fibrous joints. The union of the spinous processes and vertebrae are fibrous joints. Cartilaginous Cartilaginous Cartilaginous joints are joints in which the bones are attached by cartilage. These joints allow for only a little movment, such as in the spine or ribs. Cartilaginous joints are joints in which the bones are attached by cartilage. These joints allow for only a little movment, such as in the spine or ribs.ribs. Synovial Synovial Synovial joints allow for much more movement than cartilaginous joints. Cavaties between bones in synovial joints are filled with synovial fluid. This fluid helps lubricate and protect the bones. Bursa sacks contain* the synovial fluid. Synovial joints allow for much more movement than cartilaginous joints. Cavaties between bones in synovial joints are filled with synovial fluid. This fluid helps lubricate and protect the bones. Bursa sacks contain* the synovial fluid.

Synovial Joints Synovial joints allow for much more movement than cartilaginous joints. Cavaties between bones in synovial joints are filled with synovial fluid. This fluid helps lubricate and protect the bones. Bursa sacks contain* the synovial fluid. Synovial joints allow for much more movement than cartilaginous joints. Cavaties between bones in synovial joints are filled with synovial fluid. This fluid helps lubricate and protect the bones. Bursa sacks contain* the synovial fluid.

Ball and socket Joints A ball and socket joint allows for radial movment in almost any direction. They are found in the hips and shoulders. A ball and socket joint allows for radial movment in almost any direction. They are found in the hips and shoulders.

Ellipsoid Joints Similar to a ball and socket joint -- allow the same type of movement to a lesser magnitude. The wrist is an ellipsoid joint. Similar to a ball and socket joint -- allow the same type of movement to a lesser magnitude. The wrist is an ellipsoid joint.

Saddle Joints A saddle joint allows movement back and forth and up and down, but does not allow for rotation like a ball and socket joint. A saddle joint allows movement back and forth and up and down, but does not allow for rotation like a ball and socket joint.

Pivot Joints Pivot joints allow rotation around an axis. The neck and forearms have pivot joints. In the neck the occipital bone spins over the top of the axis. In the forearms the radius and ulna twist around each other. Pivot joints allow rotation around an axis. The neck and forearms have pivot joints. In the neck the occipital bone spins over the top of the axis. In the forearms the radius and ulna twist around each other.

Gliding In a gliding or plane joint bones slide past each other. Metacarpal and metatarsal joints are gliding joints In a gliding or plane joint bones slide past each other. Metacarpal and metatarsal joints are gliding joints

The knee

A bad joint?!? 30-50% of all sports injuries 30-50% of all sports injuries 0.2% of the general population per year for knee ligament problems 0.2% of the general population per year for knee ligament problems ACL and MCL are 90% of all sport injuries ACL and MCL are 90% of all sport injuries Women are 2-8 times greater risk Women are 2-8 times greater risk

Long bone

Long bone cont’d

Summary Human body is a very complex system Human body is a very complex system Bones are very strong mechanical members Bones are very strong mechanical members Self healing Self healing Can be very slippery Can be very slippery