The Joints PDF - Aqaba Medical Sciences University 2024

the joints Prepared By Prof. Amjad Al-Shatarat Dr.Ala’a Yousef Department of Biomedical Sciences Faculty of Dentistry Aqaba Medical sciences university 2024 1  Joints When two bones or more...

the joints Prepared By Prof. Amjad Al-Shatarat Dr.Ala’a Yousef Department of Biomedical Sciences Faculty of Dentistry Aqaba Medical sciences university 2024 1  Joints When two bones or more come Hinge together wither there is movement between them or not. Ball and socket According to the tissue laying Synovial Gliding between the articulating bones ,joints are classified into: Saddle Ellipsoid Types of Joints Sutures Fibrous Cartilaginous 10/20/2024 Prof. Shatarat 2024 2  Synovial joints are connections between skeletal components where the elements involved are separated by a narrow articular cavity 10/20/2024 Prof. Shatarat 2024 3  A- Sutures occur only in the skull where adjacent bones are linked by a thin layer of connective tissue termed a sutural ligament. B-Gomphoses occur only between the teeth and adjacent bone. In these joints, short collagen tissue fibers in the periodontal ligament run between the root of the tooth and the bony socket. C-Syndesmoses are joints in which two adjacent bones are linked by a ligament. Examples are the ligamentum flavum, which connects adjacent vertebral laminae, and an interosseous membrane, which links, for example, the radius and ulna in the forearm. 10/20/2024 Prof. Shatarat 2024 4  A-Synchondroses occur where two parts in a developing bone remain separated by a layer of cartilage, for example the growth plate that occurs between the head and shaft of developing long bones. These joints allow bone growth and eventually become completely ossified. B-Symphyses occur where two separate bones are interconnected by cartilage. Most of these types of joints occur in the midline and include the pubic symphysis between the two pelvic bones, and intervertebral discs between adjacent vertebrae 10/20/2024 Prof. Shatarat 2024 5 1-The presence of a space called a synovial Features of Synovial Joints (joint) cavity between the articulating bones 2-The bones are covered by a layer of hyaline cartilage called articular cartilage. The cartilage covers the articulating surface of the bones with a smooth, slippery surface 3-Articular Capsule A sleeve-like articular (joint) capsule surrounds a synovial joint, The articular capsule is composed of two layers, an outer fibrous membrane and an inner synovial membrane 4-Synovial Fluid 5-Accessory Ligaments, The synovial membrane secretes synovial fluid Articular Discs Its functions include reducing friction and Many synovial joints also supplying oxygen and nutrients to and removing contain accessory ligaments carbon dioxide and metabolic wastes from the called extracapsular ligaments 10/20/2024within articular cartilage.Badran chondrocytes Prof. Shatarat 20242022 & Shatarat and intracapsular ligaments 623 Selected Types of synovial joints 2-Pivot Joints Read only In a pivot joint, the rounded or pointed surface of one bone articulates with a ring formed partly by another bone and 1-Hinge Joints partly by a ligament In a hinge joint, the convex surface of one bone fits into the concave surface of another bone 3-Ball-and-Socket Joints consists of the ball-like surface of one bone fitting into a cuplike depression 10/20/2024 Prof. BadranShatarat 20242022 & Shatarat 7 of another bone24 10/20/2024 Prof. Shatarat 2024 8  Ball Socket 10/20/2024 Prof. Shatarat 2024 9 Major concepts of muscle’s actions 1- Each muscle has to be supplied by a nerve 2 For a muscle to produce a movement it has to cross over a joint 3 Muscles are attached to bones through points of attachments called origin and insertion 4 Usually the (insertion) moves towards the origin during contraction of the muscle 5 During contraction usually the muscle fibers shorten and this results in puling the insertion towards the origin over a joint 10/20/2024 Prof. Shatarat 2024 10 10/20/2024 Prof. Shatarat 2024 11  TYPES OF MOVEMENTS AT SYNOVIAL JOINTS The major movements are: 1 flexion 2 extension 3 abduction 4 adduction 5 medial and lateral rotation 5-circumduction 10/20/2024 Prof. Shatarat 2024 12 TYPES OF MOVEMENTS AT SYNOVIAL JOINTS The major movements are: 1-flexion 2-extension 3-abduction 4-adduction 5- medial and lateral rotation 5-circumduction  Abduction, Adduction Abduction is the movement of a bone away from the midline adduction is the movement of a bone toward the midline Examples of abduction include moving the humerus moving the palm laterally moving the femur laterally laterally at at the wrist joint at the hip joint the shoulder joint The movement that returns each of these body parts to the anatomical position is Rotation In rotation a bone revolves around its own longitudinal axis If the anterior surface of the bone of a If the anterior surface of a bone of the limb is limb is turned away from the midline, the turned toward the midline, the movement is movement is called lateral (external) called medial (internal) rotation Inversion is movement of the sole medially at the intertarsal joints (between the tarsals) Eversion is a movement of the sole laterally at the intertarsal joints. Dorsiflexion refers to bending of the foot at the ankle joint (Dorsiflexion occurs when you stand on your heels. Plantar flexion involves bending of the foot at the ankle joint as when you elevate your body by standing on your toes. Supination is a movement of the forearm at the proximal and distal radioulnar joints in which the palm is turned anteriorly Pronation is a movement of the forearm at the proximal and distal radioulnar joints in which the palm is turned posteriorly