Shoulder Complex PDF

youtube.com/sedativephysio Sedative Physio Shoulder Complex youtube.com/sedativephysio Sedative Physio  Introduction Bones Involved o Clavicle o Scapula o Humerus Joints True Joints o Glenohumeral o Sternoclavi...

youtube.com/sedativephysio Sedative Physio Shoulder Complex youtube.com/sedativephysio Sedative Physio  Introduction Bones Involved o Clavicle o Scapula o Humerus Joints True Joints o Glenohumeral o Sternoclavicular o Acromioclavicular False Joints o Scapulothoracic o Subacromial youtube.com/sedativephysio Sedative Physio  Introduction Components of shoulder complex constitute half of the mass of the entire upper limb GH Joint has the largest mobility U/E is connected with the trunk by SC Joint The movement between scapula and thorax is due to Sternoclavicular + Acromioclavicular Motion Movement of the shoulder is due to the combined motion of Scapula, Clavicle and Humerus ST contributes about 1/3rd of total shoulder complex motion GH contributes about 1/3rd of total shoulder complex motion youtube.com/sedativephysio Sedative Physio Sternoclavicular Joint youtube.com/sedativephysio Sedative Physio  Introduction Single structural attachment between axial and U/E Type – Synovial Sub type – Saddle DOF – 3 Movement Elevation Depression Protraction Retraction Anterior Rotation Posterior Rotation youtube.com/sedativephysio Sedative Physio  Articular Surfaces 2 Articular Surfaces Medial end of clavicle Notch by manubrium and 1st costal cartilage Joint congruency is very less Superior and posterior portions of medial clavicle do not contact sternum These are the site of attachment for SC Joint Disc Joint Capsule Interclavicular ligament youtube.com/sedativephysio Sedative Physio  SC Joint Disc Fibrocartilaginous structure between the joint surfaces. Disc is present in joint space diagonally This helps to increase the joint congruency and ultimately makes the joint much stable It has 2 attachments : Upper Portion – Posterosuperior of Clavicular Lower Portion – Manubrium and 1st costal cartilage During elevation & depression of clavicle, medial articular surface of clavicle rolls and slides on the disc. Disc remains stationary and upper attachment work as pivot. During protraction & retraction of clavicle, disc & the medial articular surface of clavicle rolls and slides together on the manubrium facet. Lower attachment of the disc work as pivot. youtube.com/sedativephysio Sedative Physio  Ligaments Sternoclavicular Ligament 2 in number (Anterior & Posterior) Restrict anterior and posterior translatory motion of medial end of clavicle Costoclavicular ligament Has 2 laminae (Anterior and Posterior) Limits the elevation Limit superior force to the clavicle by sternocleidomastoid and sternohyoid muscle Interclavicular ligament Limits excess depression Protect Brachial plexus and Subclavian artery youtube.com/sedativephysio Sedative Physio Acromioclavicular Joint youtube.com/sedativephysio Sedative Physio  Introduction Articulation between Clavicle and Acromion Process Type – Synovial Sub type – Plane DOF – 3 Movement Internal rotation External rotation Anterior tilting Posterior tilting Upward rotation Downward rotation youtube.com/sedativephysio Sedative Physio  Introduction Helps in Increasing upper extremity motion Positioning of glenoid Maximize scapula contact with thorax youtube.com/sedativephysio Sedative Physio  Articular Surfaces 2 Articular Surfaces Lateral end of clavicle Facet on acromion process Joint congruency is very less Initially this is a fibrocartilaginous union With overtime use, a joint space develops and leave a meniscal homologue It can vary in size in individuals youtube.com/sedativephysio Sedative Physio Articular Surfaces youtube.com/sedativephysio Sedative Physio Articular Surfaces youtube.com/sedativephysio Sedative Physio Articular Surfaces youtube.com/sedativephysio Sedative Physio Articular Surfaces youtube.com/sedativephysio Sedative Physio  Capsule & Ligaments Capsule of AC Joint is weak Ligaments make the joint stable There are three joints involved in the stability of AC Joint 1. Superior AC Ligament 2. Inferior AC Ligament 3. Coracoclavicular Ligament Superior AC Ligament limit the movement caused by anterior force applied on lateral clavicle Superior AC Ligament is connected with tendons of Trapezius and Deltoid. This makes the ligament stronger. Coracoclavicular Ligament provides Superior, Inferior and Rotational Stability. It has two parts: 1. Medial (Conoid Ligament) Vertical – Limit inferior translation of acromion 2. Lateral (Trapezoid Ligament) Horizontal – Limit posterior translation of lateral clavicle youtube.com/sedativephysio Sedative Physio Capsule & Ligaments youtube.com/sedativephysio Sedative Physio  Capsule & Ligaments Both ligaments limit upward rotation of scapula at AC Joint When medial force on humerus are transferred to glenoid fossa. Medial displacement of scapula on clavicle is prevented by Coracoacromial Ligament (Trapezoid Portion) youtube.com/sedativephysio Sedative Physio  Kinematics Internal – External Rotation Axis – Vertical Plane – Transverse Glenoid fossa moves anteromedially during Internal Rotation Glenoid fossa moves posterolateral during External Rotation Occurs with clavicle protraction and retraction Anterior – Posterior Tilting Axis – Frontal Plane – Sagittal Anterior Tilting Acromion moves forward Inferior angle moves backward youtube.com/sedativephysio Sedative Physio  Kinematics Anterior – Posterior Tilting Posterior Tilting Acromion moves backward Inferior angle moves forward Upward – Downward Rotation In Upward Rotation, Glenoid tilts upward and inferior angle moves laterally In Downward Rotation, Glenoid tilts downward and inferior angle moves medially The amount of available PROM at AC is limited by Coracoclavicular Ligament youtube.com/sedativephysio Sedative Physio youtube.com/sedativephysio Sedative Physio Glenohumeral Joint youtube.com/sedativephysio Sedative Physio  Introduction Articulation between Glenoid Fossa and Humeral Head Type – Synovial Subtype – Ball & Socket DOF – 3 Bones Scapula Humerus Articular Surfaces Glenoid fossa of scapula Head of Humeurs youtube.com/sedativephysio Sedative Physio  Structure Proximal Articular Surface Glenoid fossa is the proximal articular surface. It may be tilted slight upward or downward when arm is at side. Distal Articular Surface Humeral head is the distal articular surface. Surface area is larger than glenoid It has 2 different angles: 1. Angle of Inclination 2. Angle of torsion youtube.com/sedativephysio Sedative Physio  Structure Angle of Inclination Angle between Axis through humeral head and neck Longitudinal axis through shaft Normal value – 130 – 150 degrees youtube.com/sedativephysio Sedative Physio  Structure Angle of Torsion Angle between Axis through humeral head and neck Axis through condyles of lower end Normal value – 30 degrees youtube.com/sedativephysio Sedative Physio  Structure When arm hand passively at the side, articular surfaces have a little contact with each other. Inferior part of humeral head rest on small inferior portion of glenoid. youtube.com/sedativephysio Sedative Physio  Structure Glenoid Labrum The articular surface of glenoid fossa is increased by glenoid labrum Attached with the periphery of glenoid Helps in Resist humeral head translation Protect bony edge of glenoid Decrease joint friction Increase surface area Gives attachment site for Glenohumeral Ligaments Long head of triceps youtube.com/sedativephysio Sedative Physio  Structure youtube.com/sedativephysio Sedative Physio  Structure Glenoid Capsule and Ligament Capsular surface area is twice the area of humeral head $ ligaments stabilizes the capsule Superior GH Ligament Middle GH Ligament Inferior GH Ligament Coracohumeral Ligament Rotator cuff tendons also stabilize the capsule, because they are inserted in the capsule directly. youtube.com/sedativephysio Sedative Physio  Structure Superior GH Ligament Pass from superior glenoid labrum towards upper neck of humerus and inserted deep to coracohumeral ligament. Superior GH Ligament + Superior Capsule + Coracohumeral Ligament = Rotator Interval Capsule (RIC) RIC makes bridge between supraspinatus and subscapularis tendon. This ligament restricts anterior and inferior translation of the humeral head at 0 degree abduction. youtube.com/sedativephysio Sedative Physio  Structure Middle GH Ligament Runs obliquely from superior anterior labrum to anterior of proximal humerus below superior GH Ligament. This ligament limits anterior translation of the humeral head up to 45 degree abduction. youtube.com/sedativephysio Sedative Physio  Structure Inferior GH Ligament Has 3 components Anterior Ligament Band Axillary Pouch Posterior Ligament Band So k/a Inferior GH Ligament Complex (IGHLC) Major ligament for joint stability Mainly after 45 degree abduction with rotation it provides stability youtube.com/sedativephysio Sedative Physio  Structure During Abduction Axillary pouch is taken up and resist inferior head translation. youtube.com/sedativephysio Sedative Physio  Structure During Abduction + External Rotation Anterior band expands and gives anterior stability. Also resist anterior and inferior translation. youtube.com/sedativephysio Sedative Physio  Structure During Abduction + Internal Rotation Posterior band expands and gives posterior stability. Resist inferior translation. youtube.com/sedativephysio Sedative Physio  Structure Coracohumeral Ligament Has 2 bands Originate from base of coracoid process One band insert at edge of supraspinatus tendon on greater tuberosity Other band insert at subscapularis tendon on lesser tuberosity These 2 bands forms a tunnel. This tunnel is a pathway for tendon of long head of biceps. This ligament limits inferior translation Resist lateral rotation with arm adducted. youtube.com/sedativephysio Sedative Physio  Structure youtube.com/sedativephysio Sedative Physio  Kinematics Movements Flexion Extension Abduction Adduction Internal Rotation External Rotation youtube.com/sedativephysio Sedative Physio  Kinematics Flexion & Extension Axis – Frontal Plane – Sagittal ROM – 180 degrees In Flexion Humerus Moves Anterior Sliding – Posterior Rolling – Anterior In Extension Humerus moves backward Sliding – Anterior Rolling – Posterior youtube.com/sedativephysio Sedative Physio  Kinematics Abduction & Adduction Axis – Sagittal Plane – Frontal ROM – 120 degrees In Abduction Abduction will decrease if humerus is present in the neutral position or medial rotation This is because of the position of greater tubercle that is resisted by the coracoacromial arch When humerus is laterally rotated to 35-40 degrees, greater tubercle will pass under or behind the arch In this position, abduction will occur smoothly. Humerus moves laterally Rolling – Superior Sliding – Inferior youtube.com/sedativephysio Sedative Physio  Kinematics Abduction & Adduction In Adduction Humerus moves medially Rolling – Inferior Sliding – Superior youtube.com/sedativephysio Sedative Physio  Kinematics Medial and Lateral Rotation Axis – Vertical Plane – Transverse The ROM will be restricted when arm is at neutral position Because of greater and lesser tubercle When the arm is 90 degrees abducted, arc of rotation frees and ROM increases youtube.com/sedativephysio Sedative Physio  Stabilization of Glenohumeral Joint youtube.com/sedativephysio Sedative Physio  Static Stabilization GH Joint is less congruent. When humeral head is present in the neutral position, gravity influences inferior translatory force on humerus. To maintain the equilibrium, superior force is needed. This can be provided by o Active muscle contraction o Passive muscle tension There are 3 mechanisms for the static stabilization of the GH joint youtube.com/sedativephysio Sedative Physio  Static Stabilization Mechanism 1 This is done with the help of Rotator Interval Capsule. The resultant vector formed from the gravity and RIC creates a resultant force on the humeral head. This force compress the humeral head into the lower part of glenoid. This will prevent the inferior translation and will provide the stability. youtube.com/sedativephysio Sedative Physio  Static Stabilization Mechanism 1 youtube.com/sedativephysio Sedative Physio  Static Stabilization Mechanism 1 youtube.com/sedativephysio Sedative Physio  Static Stabilization Mechanism 2 In a GH Joint, the joint capsule is airtight. It creates negative pressure and cause vacuum inside the capsule. This negative pressure and vacuum will resist the inferior translation by gravity. If any tear occurs in the labrum or capsule it will cause the inferior subluxation of the GH Joint. youtube.com/sedativephysio Sedative Physio  Static Stabilization Mechanism 2 youtube.com/sedativephysio Sedative Physio  Static Stabilization Mechanism 3 In case of heavy loaded arm, passive forces are not sufficient for the stabilization. In such cases, supraspinatus participates in the active assistance for the stabilization. youtube.com/sedativephysio Sedative Physio  Static Stabilization Mechanism 3 youtube.com/sedativephysio Sedative Physio  Dynamic Stabilization Deltoid Deltoid and Supraspinatus are the prime movers for the GH Abduction. During the abduction, the forces coincide with the middle fiber of deltoid. This force is FD. This force is resolved into the parallel and perpendicular components. Parallel Component – FX (wrt long axis of humerus shaft) Perpendicular Component – FY (wrt long axis of humerus shaft) Here, the FX arm is larger and this is the translatory component. The FY component is shorter and this is the rotatory component. So, deltoid will create a large translatory force and very less rotational force. It can damage the coracoacromial arch. youtube.com/sedativephysio Sedative Physio  Dynamic Stabilization Deltoid youtube.com/sedativephysio Sedative Physio  Dynamic Stabilization Deltoid youtube.com/sedativephysio Sedative Physio  Dynamic Stabilization Rotator Cuff (Except Supraspinatus) This will include Infraspinatus Teres minor Subscapularis Provides stability and compressive force on the head of humerus to be intact with glenopid fossa. The tendons of these muscles are inserted into the glenoid capsule. Let the resultant force by ITS muscle if F(ITS). This force is resolved into parallel and perpendicular components. Parallel Component – FX (wrt long axis of humerus shaft) Perpendicular Component – FY (wrt long axis of humerus shaft) youtube.com/sedativephysio Sedative Physio  Dynamic Stabilization Rotator Cuff (Except Supraspinatus) The FX Component will counterbalance the superior pull caused by the FX Component of Deltoid. The FY Component will make a compressive force and will compress the humeral head to glenoid fossa to provide stability. The FY Component will also lead to some rotational movement. youtube.com/sedativephysio Sedative Physio  Dynamic Stabilization Rotator Cuff (Except Supraspinatus) youtube.com/sedativephysio Sedative Physio  Dynamic Stabilization Supraspinatus Let the resultant force by this muscle is FS This force is resolved into parallel and perpendicular components. Parallel Component – FX (wrt long axis of humerus shaft) Perpendicular Component – FY (wrt long axis of humerus shaft) The FX Component is very short and is counterbalanced by the inferior force of gravity. The FY Component will make a compressive force and will cause full ROM during abduction youtube.com/sedativephysio Sedative Physio  Dynamic Stabilization Supraspinatus youtube.com/sedativephysio Sedative Physio