Faizan Lecturer Al-Majma University

 Duration:  3 rd week / 3 contact hrs.  Arthrokinematics:  Typical joint morphology  Fundamental movements between joint surfaces.  Closed packed and loose pack position

 After studying this topic, the students will be able to  Identify types of the joints and their characteristics.  Define Arthrokinematics.  describe the definition and characteristics of a synovial joint.  Distinguish Arthrokinematics movements from Osteokinematics movements and explain their relationship.

 Study of movement occurring between the two articulating surfaces.  Types of Arthrokinematic movements (Synonym: accessory movements, joint play)  Distraction.  Compression.  Rolling.  Spinning.  Sliding.  gliding

 Separation between the two articular surfaces along the longitudinal axis of the distal segment

 Approximation between the two articular surfaces along the longitudinal axis of the distal segment.

 new points on one rotating articular surface meet new points on another articular surface

 same point on one rotating articular surface meet new points on another articular surface

 a combination of roll and slide between two incongruent joint surfaces.

 Same point meet the same point.  Eg: superior radio-ulnar joint

OSTEOKINEMATICS MOVEMENT ARTHROKINEMATICS MOVEMENT  Movement of bone.  voluntary movement.  Also known as physiological movement.  Resulting from voluntary muscle contraction.  Movement between joint surfaces.  Involuntary movement.  Also know as joint play, accessory movement.  Resulting from movement of the bones.

 Study of internal structure and configuration of a joint is known as morphology of the joint.  In order to study the morphology of human joint we need to know the different types of joint in the human body.

 Structurally joints are classified as following:  Fibrous joints : the bones are held together by fibrous connective tissue that is rich in collagen fibers. No synovial cavity.  Cartilaginous joints : the bones are held together by cartilage. No synovial cavity.  Synovial joints : the bones forming the joint have a synovial cavity and are united by dense irregular connective tissue.

 Functionally, joints are classified as one of the following:  Synarthrosis : an immovable joint.  Amphiarthrosis : a slightly movable joint.  Diarthrosis : a freely movable joint. All diarthroses are synovial joints.

 These are joints that lack a synovial cavity. They permit little or no movement.  Sutures : thin layer of dense connective issue. Unites bones of the skull. Because a suture is immovable, it is functionally classified as a synarthrosis. Some sutures are replaced by bone in the adult. Such a suture is called synostosis.

 Syndesmoses : There is a greater distance between the bones and more fibrous connective tissue. The tissue is either arranged as a bundle (ligament) or as a sheet (interosseus membrane). Example tibia/fibula. Because it permits slight movement, a syndesmosis is classified functionally as an amphiarthrosis.

 Gomphoses - this is a type of fibrous joint in which a cone-shaped peg fits into a socket. The only example are the articulations of the roots of the teeth with the sockets of the alveolar processes of the maxillae and mandible. The dense fibrous connective tissue is called the periodonatal ligament. This is functionally classified as a synarthrosis.

 This also lacks a synovial cavity and permits little or no movement.  Synchondroses : here the connecting material is hyaline cartilage. An example is the epiphyseal plate that connects the epiphysis and diaphysis of a growing bone. Another example is the joint between the first rib and manubrium of the sternum.

 Symphyses : here the ends of the articulating bones are covered with hyaline cartilage but the bones are connected by a broad flat disc of fibrocartilage. Examples: pubic symphysis, junction of the manubrium and sternum, intervertebral joints. Functionally, this is an amphiarthrosis, a slightly movable joint.

 These have a space called a synovial cavity between the articulating bones. Classified functionally as diarthroses.  The bones at synovial joint are covered by an articular cartilage. Consists of two layers, an outer fibrous capsule and an inner synovial membrane.  Fibrous capsule-ligaments  Synovial membrane-areolar connective tissue with elastic fibers. Adipose tissue-articular fat pads.

 Synovial fluid : the synovial membrane secretes this. Consists of hyaluronic acid and interstitial fluid filtered from blood plasma. Reduces friction by lubricating the joint. Supplies nutrients and removes metabolic wastes. Contains phagocytic cells. Benefits of a “warm up” before exercise is that it stimulates the production and secretion of synovial fluid.

 Plane joint (irregular or arthrodial)  hinge (ginglymus)  Pivot (trochoid or screw)  Condyloid (ovoid or ellipsoidal )  saddle (sellar)  ball-and-socket (spheroidal)

 Plane Joint (Irregular Or Arthrodial)  Non-axial Joint  Only Sliding Movements Present  E.G. Facet Joint Of The Spine  Hinge  Uniaxial Joint  Degree Of Freedom = 1  E.G. Humeroulnar Joint  Pivot  Uniaxial Joint  Degree Of Freedom = 1  E.G. Humeroradial Joint  Condyloid  Biaxial Joint  Degree Of Freedom = 2  Ideal Joint Surface: Ovoid  E.G. Radiocarpal Joint  Saddle  Biaxial Joint  Degree Of Freedom = 2  Ideal Joint Surface: Sellar  E.G. First Carpometacarpal Joint  Ball-and-socket  Triaxial Joint  Degree Of Freedom = 3  E.G. Glenohumeral Joint

 Definition: the position that both of the articular surfaces are in the maximum congruency status for a joint, resulting in the greatest mechanical stability for that joint  In the close-packed position, most ligaments and capsules surrounding to the joint are taut  example: for the glenohumeral joint the close- packed position is abduction of 90 & ordm; and full external rotation  loose-packed position: all positions other than close-packed position