Joints Musculoskeletal Block - Lecture 2

Objective:

✓ Define the term “Joint” . ✓ Describe the classification of the 3 types of joints & give an example of each. ✓ Describe the characteristics of synovial joints. ✓ Describe the classification of synovial joints & give an example of each. ✓ List factors maintaining stability of joints. ✓ Recite “Hilton’s law” for nerve supply of joints.

Color index: Important In male’s slides only In female’s slides only Extra information, explanation

Editing file Click here for Contact us: useful videos [email protected] Joints

It is the site where two or more bones meet together Definition union of two or more bones of the body

01 Fibrous

Classification 02 Cartilaginous Of Joints

They are classified according to: 03 Synovial tissues that lie between the articulating bones

1) Fibrous joints : The articulating surfaces are joined by fibrous connective tissue, where No or very mild movement( Negligible ).

For example :

Inferior tibiofibular joints Skull sutures: Gomphosis (syndesmosis):

1 2 3

● ● . no movement ● minimal movement dental alveolar joints ● temporary (as it ● permanent joints. Articulation between root of the tooth with ossify later) They will the mandible (between the teeth & their become bones socket) 2) Cartilaginous Joints:

Happens when two bones are joined by cartilage. They are classified into 2 types:

Primary Cartilaginous Secondary Cartilaginous: (synchondrosis): (midline* or symphysis)

Structure: Structure: 1 The bones are united by a plate or a bar of 1 The bones are united by a plate of hyaline cartilage. fibrocartilage. & it’s one where bone and cartilage meet. It’s Their articulating surfaces are covered a very strong joint and immobile. by a thin plate of hyaline cartilage.

2 Movement: 2 Movement: No movement, Little movement, temporary joints (ossify later). permanent joints.

-Between the Epiphysis and the Diaphysis of a Example: 3 growing bone. note: (epiphyseal plate). 3 -Joints between the Vertebral Bodies (intervertebral discs). -Between the First Rib and the Sternum (1st -Symphysis Pubis. sternocostal joint). → junctions of ribs with their costal cartilage. between the two hip bones .

The rest of the sternocostal joints are synovial plane joints)

3) Synovial Joints:

The articular The 2 surfaces are bones(articulating Freely movable covered by a thin The capsule is bones) are joined by a layer of hyaline joints.because of the fibrous capsule, A joint cavity reinforced by synovial cavity and cartilage enclosed within ligaments both fluid which is attached to (articular the margins of the capsule. internally and cartilage). This can externally. articular surfaces & also decrease friction enclosing the joint. along with the synovial fluid

Note: The joint cavity contain the synovial fluid which is secreted from the synovial membrane

All joints in appendicular skeleton are synovial joint

Synovial membrane : a thin vascular membrane lining the inner surface of the capsule. It produces the synovial fluid.

Synovial fluid : a lubricating fluid produced by the synovial membrane in the joint cavity. Capsule The fluid minimizes the friction between the articular surfaces. Classification of Synovial joints:

Synovial joints can be classified according to:

● The arrangement (shape) of the articular surfaces. ● The range of movement that are possible

According to the range of movement they are classified into:

Arrangement The articulating surfaces are ● Plane flat and the bones slide on one another. synovial joints

Examples -Intercarpal & intertarsal joints Movement - Sternoclavicular joint Gliding Movement (minimal) - Acromioclavicular joint - Between the 2nd and 7th sternocostals

Arrangement ● Axial The articulating surfaces synovial joints occur along axis.

Movement: -Transverse (x-axis): flexion and Examples extension - Elbow joint -Longitudinal (y-axis): rotation - Shoulder joint -Antero-posterior (z-axis): abduction - Radio-ulnar joint and adduction

Axial joints are divided to:

Multi-axial Uniaxial Biaxial (polyaxial) Uniaxial Biaxial Multiaxial Hinge Pivot Ellipsoid Saddle Ball & Type an elliptical convex fits in The articular surfaces an elliptical (oval) concave are reciprocally socket articular surface) concavoconvex.

Transverse & They resemble a A ball–shaped head of a bone fits into a antero-posterior saddle on a Transverse longitudinal horse’s back socket-like concavity Axis of another 1.Flexion & 1.Flexion & 1.Flexion & extension. extension. extension.

Flexion & 2.Abduction & 2.Abduction & 2.Abduction & Rotation Movement extension adduction. adduction. adduction.

BUT rotation is Small range rotation along of rotation separate axis impossible.

1.Elbow joint 1.Radio-ulnar Carpometaca-r 1.Shoulder joint joint(supination & Wrist joints pal joint of the pronation) thumb 2.Hip joint Examples 2.Ankle joint 2.Atlantoaxial joint

1- Hinge e.g. Elbow joint. 2- pivot e.g. Radio-ulnar joint. 3- Ellipsoid e.g. Wrist joint.

4- saddle e.g. carpometacarpal 5- Ball & socket e.g. hip joint. joint of the thumb

Helpful video Factors Affecting Stability of Synovial Joints

1. The shape of articular surfaces:

2. Strength of the ligaments: ● The ball and socket shape of the Hip

joint is a good examples of the They prevent excessive movement in importance of the shape of the bone a joint. to maintain joint stability.

e g. Cruciate ligaments of the knee ● The shape of the bones forming the joint. Knee joint has nothing to do for stability.

3. Tone of the surrounding muscles:

● In most joints, it is the major factor controlling stability. 4. Atmospheric pressure e.g. The short muscles around the shoulder joint (Rotator cuff muscles) keeps the head of the humerus in the shallow glenoid cavity.

1. The shape of the articular surfaces: 2. Strength of the ligaments: 3. Tone of the surrounding muscles:

NERVE SUPPLY OF JOINTS

● The capsule and ligaments receive an abundant sensory nerve supply.

Hilton’s Law: “A sensory nerve supplying a joint also supplies the muscles moving that joint and the skin overlying the insertions of these muscles.” SUMMARY med436 SUMMARY med436

MCQs

Q1: The primary cartilaginous Q2: Sternoclavicular joint is a Q3: The rotation of the axial joint is found in the ? plane synovial joint take synovial joint is in the _____ place between the ? Axis ? A.Symphysis Pubis. B.Intercarpal Joints. A.Sternum and the clavicle A.Transverse axis. C.Epiphyseal Plate. B.2nd rip and 3rd rip. B.Longitudinal axis. D.Elbow joint. C.Ulna and the humerus C.Antero-posterior axis. D.Ulna and the radius D.Z-axis.

Q4: what is the other name Q5: joints are classified Q6: the site where two or of Inferior tibiofibular joints ? according to ? more bones meet together ?

A.Gomphosis A. type of bone A. Cartilage B.syndesmosis B.tissues that lie between the B. Tendon C.synchondrosis articulating bones C. Joint D.symphysis C. Number of bone D.non of the above D. Size of bone

Q7: what type of joint that Q8: Secondary cartilaginous Q9: Which type of uniaxial has No or very mild joints are united by ? synovial joints can do movement ?. supination & pronation of the A.Hyaline cartilage forearm? A. Fibrous joints B.elastic cartilage A.Hinge B. Cartilaginous joints C.fibrous tissue B.Pivot C. Synovial Joints D.fibrocartilage C.Saddle D. Non of the above D.Ellipsoid

Q10: Which of the following is Q11: In most joints, it is the Q12: According to Hilton's law “A true about Multiaxial major factor controlling sensory nerve supplying a joint (polyaxial) synovial joints ? stability ? also supplies…” relating to that joint ?

A.Flexion & Extension. A.The shape of the articular surfaces. A.Bone & muscles B.Rotation along separate B.Strength of the ligaments. B.Muscles & skin axis. C.Tone of the surrounding C.Bone & skin C.Abduction & Adduction. muscles. D.None of the above

D.All of the above. D.Atmospheric pressure.

C 6) B 12)

B 5) C 11)

B 4) D 10)

B 3) B 9)

A 2) D 8)

C 1) A 7) SAQs:

Q1:The joint cavity contain the ______which is secreted from the ______.

Q2: list the 3 type of joint

Q3:List the 5 types of the axial synovial joints with an example for each.

4-Ball & socket e.g. hip joint. 5- Saddle e.g. carpometacarpal joint of the thumb. the of joint carpometacarpal e.g. Saddle 5- joint. hip e.g. socket & 4-Ball

Q31-Hinge e.g. Elbow joint. 2-Pivot e.g. Radio-ulnar joint. 3- Ellipsoid e.g. Wrist joint. Wrist e.g. Ellipsoid 3- joint. Radio-ulnar e.g. 2-Pivot joint. Elbow e.g. Q31-Hinge

1-Cartilaginous 2-Fibrous 3- Synovial 3- 2-Fibrous 1-Cartilaginous Q2:

Q1:Synovial fluid - synovial membrane. synovial - fluid Q1:Synovial

This lecture was done by:

Noura aldahash Sadeem alhazmi Bassam alasmri

Team leaders: Mayasem Alhazmi Fahad Alajmi

SPECIAL THANKS TO THE AMAZING #MED438 ANATOMY TEAM