the pectoral girdle e-learning
TRANSCRIPT
The Upper Limb:The Upper Limb:
Pectoral (Shoulder) GirdlePectoral (Shoulder) Girdle
Upper Limb DivisionsUpper Limb Divisions
1. Pectoral (Shouldar) Girdle
incomplete bony ring
formed by Scapula & Clavicle
2. Arm
between shoulder & elbow
contain the Humerus
3. Forearm
between elbow & wrist
contain Ulna & Radius
4. Hand
contain carpals, metacarpals
& phalanges
Bones of Pectoral GirdleBones of Pectoral Girdle
Clavicle: long bone
Scapula: flat bone
Bone of The ArmBone of The Arm
Humerus: long
Clavicle
“S” shaped bone (resilience)
medial 2/3 convex anteriorly , lateral 1/3 concave ant.
Sternal end (rounded) manubrium & 1st rib
Acromial end (flat) acromion
importance of the clavicle:importance of the clavicle:
Connects upper limb to axial skeleton (strut)
Protects neurovascular bundle that supply the upper limb
Transmits shocks from upper limb to axial skeleton
Clinical: Clinical: Fractures of ClavicleFractures of Clavicle
Common
indirect impact to upper limb
Between middle & lateral thirds
Medial part / lateral
-Shoulder drop
-Medial rotation of humerus
Scapula (shoulder blade)Scapula (shoulder blade)
Triangular flat boneTriangular flat bone
3 borders3 borders
3 angles3 angles
2 surfaces:2 surfaces:
Anterior (Anterior (costalcostal) surface) surface
22ndnd – 7 – 7thth ribs ribs
Posterior (Posterior (spinousspinous) surface) surface
Left Scapula (Posterior Aspect)Left Scapula (Posterior Aspect)
• 1.Coracoid Process
• 3. Superior border
• 4. Supraspinous Fossa
• 6. Scapular Spine
• 7.Medial border
• 8.Infraspinous Fossa
• 9.Inferior Angle
• 10.Lateral border
• 11.Glenoid Cavity Margin
• 12.Acromion Process
Humerus (brachial bone)Humerus (brachial bone)
The arm bone
Articulates with:
Scapula (shoulder joint)
Radius & Ulna (elbow joint)
Upper part Upper part
1. Head (1/3 of sphere)
2. Anatomical Neck
3. Lesser Tubercle
4. Intertubercular Groove
5. Greater Tubercle
6. Surgical Neck
7. Deltoid Tuberosity
Joints of Pectoral GirdleJoints of Pectoral Girdle
3 Joints:
Sterno-clavicular joint
Acromio-clavicular joint
Gleno-humeral joint
(Shouldar joint)
Joint QuestionsJoint Questions
1. What is the type of that joint?
2. What are the articular surfaces of that joint?
3. What are the supporting ligaments?
4. What kind of movement is available?
5. Any special characteristics of the joint?
Sterno-Clavicular JointSterno-Clavicular Joint
Type: Synovial (saddle shaped, or double plane)
Surfaces: sternal end of clavicle
Manubrium & 1st costal cartilage
Movements:
ant., post., sup. & inf.
Characteristics: Articular disc
Shock absorberShock absorber
GlenoHumeral (Shoulder) JointGlenoHumeral (Shoulder) Joint
Type: Synovial (ball & socket)
Articulations:
Head of humerus
Glenoid cavity of scapule
Ligaments:
1. Fibrous Capsule
2. Gleno-humeral lig.(3)
3. Coraco-humeral lig.
4. Transverse humeral lig.
Movements:
Circumduction
Includes??
Characteristics:
The fibrous capsule is Weak inferiorly
due to:
1. penetrated inferiorly by tendon of long head of triceps
2. Joint is surrounded (stabilized) by group of muscles called: Rotator Cuff muscles
*except inferiorly
Muscles of The Shoulder Region:Muscles of The Shoulder Region:
Thoraco-appendicular MusclesThoraco-appendicular Muscles& Scapulo-humeral Muscles& Scapulo-humeral Muscles
Anterior Thoracoappend. MusclesAnterior Thoracoappend. Muscles
Pectoralis Major
Pectoralis Minor
Serratus Anterior
Subclavius
Pectoralis MajorPectoralis Major
Fan shape muscle
Origin:
Clavicular & sternocostal heads
Insertion:
Humerus
Innervation:
Medial & Lateral pectoral nerves
Action:
Adduction of humerus
Pectoralis MinorPectoralis Minor
triangular shaped muscle
Origin:
3rd, 4th & 5th ribs
Insertion:
Coracoid process
Innervation:
Medial pectoral nerves
Action:
Depress scapula, elevate ribs
Pectoralis Major & MinorPectoralis Major & Minor
Serratus Anterior MuscleSerratus Anterior Muscle
Serrated border
Origin:Outer surfaces of upper 8 ribs
Insertion:Medial border of scapula
Innervation:Long thoracic n.
Action:Pulls scapula forward along the ribsKeeps the scapula in contact to thoracic cage
Clinical: Winged ScapulaClinical: Winged Scapula
Medial border of scapula hangs away from thoracic wall
1. Damage to serratus anterior m.
2. Injury to long thoracic n.
During fights
Winged Scapula
SubclaviusSubclaviusSmall muscle that extends:
Middle 1/3 of clavicle
1st costal cartilage
Innervation:
Nerve to subclavius
Action:
Depresses the clavicle
Posterior Thoracoappendicular MusclesPosterior Thoracoappendicular Muscles “Only names to be able to distinguish them in the lab”
Trapezius
Latissimus dorsi m.
Levator scapulae
Rhomboid major
Rhomboid minor
Scapulo-humeral MusclesScapulo-humeral Muscles“Read the table in your book for innervation, origin, insertion & “Read the table in your book for innervation, origin, insertion &
main action”main action”
Deltoid
Teres Major
Teres Minor
Supraspinatus
Infraspinatus
subscapularis
Rotator Cuff MusclesRotator Cuff Muscles
4 muscles that inserted around shoulder joint & form a musculotendinous cuff
Cover the joint from 3 directions:
Superior: supraspinatus
Anterior: subscapularis
Posterior: infraspinatus & teres minor
Fxn.
Stabilize shoulder joint
Anterior Superior
Posterior