Chapter 4 ARTHROKINEMATICS Points to Remember Normal end

Chapter 4 ARTHROKINEMATICS

Points to Remember Normal end feel can be described as bony, soft tissue stretch, or soft tissue approximation Abnormal end feel can be described as bony, boggy, empty, springy block, or muscle spasm Types of arthrokinematic motion and roll, glide or spin. According to the concave - convex rule, concave joint surface move in the same direction as the joint or body segment’s motion, while convex surfaces move in the opposite direction as the joint in motion When a joint is congruent , it is in the close-packed (tight) position. When the joint is incongruent, it is in the open-packed (loose) position.

Osteokinematic Motion End Feel: a subjective assesment of a quality of the feel when slight pressure is applied at the end of the joint Normal bony end feel is characterized by a hard & abrupt limit to passive joint motion Normal soft tissue stretch : a firm sensation that has slight give when the joint is taken to end ROM Soft tissue approximation: when muscle bulk is compressed giving a soft end feel Abnormal Boney feel – a sudden hard stop usually felt well before the end of normal ROM Muscle Spasm – reflexive muscle guarding motion Empty end feel – movement produces considerable pain Springy Block - a rebounf movement is felt at the end of the ROM

Accessory Motion Terminology Component Movement – are motions that accompany active motion but are under voluntary control Joint Play Movements – passive movements between joint surface done by passing applying external force Joint Mobilization – a passive oscillatory motion or

Convex- Concave Rule Important: knowing that a joint surface is concave or convex is important because shape determines motion Concave-Convex Rule: describes how the differences in shape of bone ends require joint surfaces to move in a specific way during joint movement A concave joint surface will move on a fixed convex surface in the same direction the body segment is moving The Concave joints surface moves in the same direction as the body segment motion The Convex joint surface moves in the opposite direction as the body segment motion

Accessory Motion Traction – occurs when external force exerted on a joint, causing the joint surface to pull apart Approximation – occurs when external force is extended on a joint, causing the joint surface to be pushed close together Shear – occurs when panedel to the surface, shear force results in a glide motion at the joint Bending – occurs when an other- than – vertical force is applied, resulting in compression of the concave side and distraction on the convex side

Types of Arthrokinematic Motion Roll: rolling of one joint surface to another Glide/ Slide: linear movements of the joint surface to other joints Spin: Rotation of a moveable joint surface on a fixed curve

Chapter 3 ARTICULAR SYSTEM

Types of Joints Joint – a connection between 2 bones to allow motion

Types of Joints Fibrous Joint – has a thin layer of fibrous periosteum between the 2 bones, such as in the suture of the skull Synarthrosis: the ends of the bones are shaped to allow them to interlock. This joint has no motion between the bones, the purpose is to provide shape and strength Syndesmosis/Ligaments: ligaments intercross membranes holding the joints together. Twisting or stretching movement Gomphosis: “ bolting together” joint occurs between a tooth and wall of its dental socket in the mandible maxilla

Types of Joints Cartilaginous Joint/ Amphiarthrodial : Small amount of motion such as bonding or twisting, and some compression

Types of Joints Synovial Joint/ Diarthrodial allow free motion not as stable Joints: Nonaxial: glides; “Plane” Uniaxial Joint: 1 plane around 1 axis; “Hinge” or “Pivot” Biaxial Joint : 2 different directions for 1 joint; “Condyloid” or “Saddle” Trixial Joint : occurs in 3 axes; “Ball and Socket” Shapes of Joints Pivot Joint: pivot motion is a transverse plane around the longitudinal axis Condyloid Joint: bidirectional motion Saddle Joint : fits together like a horseback rider on a saddle

Types of Joints # of Axes Shape of Joint Motion Nonaxial Plane (Irregular) Gliding Uniaxial Hinge Flexion/Extension Pivot Rotation Biaxial Triaxial (multiaxial) Condyloid (Ellipsoidal) Flexion, Extension, Abduction, Adduction Saddle Flexion, Extension, Abduction, Adduction, Rotation (Accessory) Ball and Socket Flexion, Extension, Abduction, Adduction, Rotation

Degrees of Freedom Uniaxial jt has motion around 1 axis and in 1 plane = 1 degree of freedom Biaxial jt = 2 degrees of freedom Triaxial jt = 3 degrees of freedom is the max # an individual jt can have How many degrees of freedom does the arm have?

Planes and Axes Planes of action – fixed lines of reference along which the body is divided Sagital Line - passes through the body into the right and left parts Frontal Plane (Coronal Plane) – Passes through the body from side to side and divides the body into front and back parts Transverse Plane (Horizontal Plane) – Passes through the body horizontally and divides the body into equal parts Cardinal Plane – whenever a plane passes through the body horizontally and divides the body into top and bottom parts Center of Gravity – the point where three cardinal planes intersect each other Sagital Axis – a point that runs through a joint from side to side Vertical Axis (Longitudinal Axis) – runs through a joint from top to bottom

Joint Structure Bones – articulate the amount and direction of motion Ligaments – connective tissue to help control joint motion Capsule – protects joints and bone surfaces Synovial Membrane- a vascular connective tissue that secretes synovial fluid Synovial Fluid – a thick, clear fluid, that lubricants the articular cartilage Articular Cartilage – covers the ends of opposing bones. Provides blood. Fibrocartilage – Shock absorber weight banning joints like knee Elastic Cartilage – Help maintain a structure's shape Tendon – connect muscle to bone Bursae - padlike sacs in joints

Levers Limbs are like machines The action of a muscle pulling on a bone often works like a type of simple machine called a LEVER. 1 st CLASS LEVER: the weight and force are on the opposite sides of the fulcrum/axis (the fulcrum/axis is the middle) 2 nd CLASS LEVER: the load/weight is between the fulcrum and the force (the load/weight is in the middle) 3 rd CLASS LEVER: the force in between the fulcrum and the load (the force is in the middle)

Common Pathological Terms Dislocation: Complete separation of the 2 articular surface of a joint Subluxation: Partial dislocation of a joint, usually occurs over a period of time (degenerative arthritis) Osteoarthritis: type of arthritis that is caused by the breakdown and eventual loss of the cartilage of one of the most joints Sprains: partial or complete tearing of the ligament fibers Strain: overstretching the muscle fibers as with sprains and strains

Common Pathological Terms Tendonitis – is an inflammation of the tendon Synovities – is an inflammation of the synovial membrane Tendosynovitis- an inflammation of the tendon sheath and is often caused by repetitive use Bursitis – an inflammation of the bursa Capsulitis – and inflammation of the joint capsule

Did you know turtles can breathe through their butts? (: