Shoulder Complex Past Paper PDF 2024

Shoulder Complex UOW T O LEARN ANATOMY WITH CADAVERS IS A PRIVILEGE Body CADAVERS ARE TO BE TREATED WITH DIGNITY & RESPECT AT Donation ALL TIMES ANY BREA...

Shoulder Complex UOW T O LEARN ANATOMY WITH CADAVERS IS A PRIVILEGE Body CADAVERS ARE TO BE TREATED WITH DIGNITY & RESPECT AT Donation ALL TIMES ANY BREACH MAY RESULT IN Program ACADEMIC MISCONDUCT ANATOMY LABORATORY uow.edu.au #ThisIsUOW  ABBREVIATIONS SP: spinous process Contralateral: opposite side of C/Sp: Cervical spine body T/Sp: Thoracic spine Ipsilateral: same side of body UR = Upward Rotation UT upper traps Elv = Elevation MT middle traps Ret = Retraction LT lower traps Pro = Protraction SA: serratus anterior Inspir = inspiration SHR: scapulohumeral rhythm (breathing in) PRUJ = Proximal radioulnar joint  Lecture Sub-Sections Shoulder: 1 Joints: Glenohumeral Joint (GHJ) + labrum Structure, Ligaments, Pathology Shoulder: 2 Joints: Sternoclavicular Joint (SCJ); Acromioclavicular Joint (ACJ); Scapulothoracic Joint (STJ); Cervicothoracic spine Structure, Ligaments, Pathology Shoulder: 3 Shoulder complex ROM & Scapulohumeral rhythm Shoulder: 4 Muscles that move & stabilise scapula Attachments/action/function Strength/stretch, Pathology Shoulder: 5 Muscles that move & stabilise GHJ Attachments/action/function Strength/stretch, Pathology Shoulder: 6 Rotator Cuff Muscles Attachments/action/function Strength/stretch & Pathology Shoulder 1  Function Connect upper limb to trunk Move tool (hand) in space Change length of UL Rohan, J., Yokochi, C & Lutjen-Drecoll, E, 2002  Joint videos Articular surfaces shoulder complex – Glenohumeral Joint (GHJ) + labrum – Sternoclavicular Joint (SCJ) – Acromioclavicular Joint (ACJ) – Scapulothoracic Joint (STJ) – Cervicothoracic spine Alignment/Posture Ligaments ROM  Shoulder Complex includes: Glenohumeral Joint (GHJ) Sternoclavicular Joint (SCJ) Acromioclavicular Joint (ACJ) Scapulothoracic Joint (STJ) Cervicothoracic spine Rohan, J., Yokochi, C & Lutjen-Drecoll, E, 2002 Rohan, J., Yokochi, C & Lutjen-Drecoll, E, 2002 GHJ Structure Articular surfaces Humerus: head Scapula: glenoid fossa Labrum:  depth, articular fit Capsule: – very loose, allows 2-3cm distraction – Attachment sites: labrum & rim of glenoid fossa anatomical neck of the humerus Rohan, J., Yokochi, C & Lutjen-Drecoll, E, 2002  Labrum Rohan, J., Yokochi, C & Lutjen-Drecoll, E, 2002 GHJ Ligaments Glenohumeral: superior/middle/inferior (SGHL, MGHL, IGHL), capsular ligaments fxn: limits anterior shear (dislocation) of head of humerus on glenoid; limit ER GHJ Coracohumeral: (CHL) blends with superior joint capsule & supraspinatus tendon fxn: limits inferior shear (dislocation) of head of humerus on glenoid, support weight of UL  GHJ Ligaments CAL forms sub- acrominal arch – (CAL) joins 2 bony processes of scapula (CHL) (SGHL, MGHL, IGHL) Rohan, J., Yokochi, C & Lutjen-Drecoll, E, 2002  Passive Stability GHJ Weight UL → inferior shear HOH Resisted by superior aspect GHJ capsule + coracohumeral ligament + long head biceps (superior shear) Intermittent activity supraspinatus prevents creep of joint capsule & coracohumeral ligament  Dynamic Stability Shoulder complex most mobile joint, dynamic stabilizers are crucial 2 types: 1. Rotator cuff muscles = “dynamic ligament” GHJ – Compress articular surfaces for stability – Guide arthrokinematics - control movement of HOH within glenoid fossa - maintain centralization of the humeral head 2. Scapula stabilizers: Stab GHJ via scapula position (tilt)  Pathology GHJ Subluxation = partial dislocation Dislocation: complete separation joint surfaces Anterior – tear anterior capsule & Glenohumeral ligaments – common Posterior – tear posterior capsule Multidirectional instability – Atraumatic, results from repetitive overhead movements or congenital joint features Anterior Dislocation Mechanism: Arm behind body → HOH anterior/inferior relative to glenoid; Can have associated injuries: Bankart lesion Hill-Sachs lesion Bankart lesion: avulsion anterior labrum band IGHL from anterior inferior glenoid (osseus bankart: associated # anterior inferior glenoid) Hill-Sachs lesion: humeral head 'collides' with the anterior glenoid → defect & deformity head of humerus (HOH) Posterior Dislocation Mechanism: 90º F → HOH posterior relative to glenoid Inferior subluxation after stroke (nerve injury) → HOH inferior relative to glenoid - tear (creep) superior capsule & coracohumeral ligaments  Pathology GHJ Degenerative: Arthritis (degeneration)  Pathology GHJ Inflammatory: Adhesive capsulitis (frozen shoulder) – → fibrosis GHJ joint capsule – → gradual, progressive stiffness & ↓ ROM (typically ER & ABD)  Bursa Fxn: limit friction between opposing surfaces numerous around the shoulder Netter, 2003 Pathology Subacromial Impingement Subacromial Space: ↓ space in 90º ABD → impingement of bursa & supraspinatus tendon between: (i) greater tubercle & HOH against (ii)acromion process & subacromial arch (coracoacrominal ligament) Clinical Impingement tests Painful Arc Test Patient actively abducts shoulder complex in plane of scapula Positive test: pain between 60-120º ABD  Clinical Impingement tests Hawkins Kennedy Impingement Test Examiner positions patients in 90º F GHJ/elbow & then MR the GHJ Positive test: pain Shoulder 2  Lecture Sub-Sections Shoulder: 1 Joints: Glenohumeral Joint (GHJ) + labrum Structure, Ligaments, Pathology Shoulder: 2 Joints: Sternoclavicular Joint (SCJ); Acromioclavicular Joint (ACJ); Scapulothoracic Joint (STJ); Cervicothoracic spine Structure, Ligaments, Pathology Shoulder: 3 Shoulder complex ROM & Scapulohumeral rhythm Shoulder: 4 Muscles that move & stabilise scapula Attachments/action/function Strength/stretch, Pathology Shoulder: 5 Muscles that move & stabilise GHJ Attachments/action/function Strength/stretch, Pathology Shoulder: 6 Rotator Cuff Muscles Attachments/action/function Strength/stretch & Pathology Sternoclavicular Joint (SCJ) Articular Surfaces: Clavicle: medial Manubrium & costal cartilage 1st rib Disc: transects joint → 2 joint cavities Fxn disc: – stability –  jt. congruency – shock absorption – force transmission Sternoclavicular Joint (SCJ)  SCJ Ligaments Ant/Post. Sternoclavicular ligaments: – fxn: limit ant/post dislocation SCJ (clavicle on manubrium) Costoclavicular ligaments: – act as fulcrum for movt (elv/dep, pro/retraction) – limit superior gliding of medial clavicle Interclavicular ligaments: – limit excessive depression, inferior glide medial clavicle  Pathology SCJ Anterior: Dislocation more common Indirect force through upper limb Posterior: Direct impact to medial clavicle Can have life-threatening complications Acromioclavicular Joint (ACJ) Articular Surfaces: Clavicle: lateral end Scapula: acromion process Disc: variable occurrence Acromioclavicular Joint (ACJ)  ACJ Ligaments Coracoclavicular Ligament : 1°stabiliser ACJ Fxn: – limit superior dislocation ACJ (clavicle on acromion) – force transmission scapula to clavicle Superior/Inferior ACJ Ligaments: – reinforced superiorly by aponeurotic insertion of trapezius & deltoid muscle No muscle stability provided by deltoid or upper trapezius muscles  Pathology ACJ Dislocation  Scapulothoracic Joint (STJ) Movt SCJ & ACJ ➔ STJ Resting position scapula depends on equilibrium of scapula stabiliser muscles Separated from rib cage by layers of interposed muscle Rohan, J., Yokochi, C & Lutjen-Drecoll, E, 2002 Surface anatomy  Pathology STJ Scapula winging  Cervicothoracic Spine (C/T Sp) Related to shoulder girdle by: Muscle attachment STJ SCJ (connects manubrium/Rib 1 to 1st Thoracic vertebrae) Rohan, J., Yokochi, C & Lutjen-Drecoll, E, 2002  Pathology C/T Sp Increased thoracic kyphosis affects ROM Shoulder 3  Lecture Sub-Sections Shoulder: 1 Joints: Glenohumeral Joint (GHJ) + labrum Structure, Ligaments, Pathology Shoulder: 2 Joints: Sternoclavicular Joint (SCJ); Acromioclavicular Joint (ACJ); Scapulothoracic Joint (STJ); Cervicothoracic spine Structure, Ligaments, Pathology Shoulder: 3 Shoulder complex ROM & Scapulohumeral rhythm Shoulder: 4 Muscles that move & stabilise scapula Attachments/action/function Strength/stretch, Pathology Shoulder: 5 Muscles that move & stabilise GHJ Attachments/action/function Strength/stretch, Pathology Shoulder: 6 Rotator Cuff Muscles Attachments/action/function Strength/stretch & Pathology Range of Motion Shoulder Complex Requires all joints to fxn: F: 165-180° E: 60° ABD: 160-180 (plane: frontal versus plane of scapula) MR: 70°, LR: 90°. (measured with elbow in 90°F) Medial rotation Lateral rotation Range of Motion Flexion Abduction Internal rotation in 90º abduction  SCJ/ACJ → STJ Movements No pure movements, combination of elevation/depression (elv/dep) & tipping protraction/retraction (pro/ret) & winging upward rotation/downward rotation (UR)/DR) of glenoid fossa (also called lateral rotation/medial rotation of inferior angle elv/dep ret/prot DR/UR  Scapulohumeral Rhythm “timed & coordinated simultaneous movement of the scapula & humerus”” fxns to: Allow large ROM (less compromise to stability) Maintain optimal position HOH within glenoid,  jt. congruency while  shear forces Limits excessive muscle shortening or lengthening, hence active insufficiency Scapulohumeral Rhythm Arthrokinematics 0-30° ABD GHJ ABD, “anchor” scapula 30-90° ABD GHJ ABD & STJ UR/Pro/Elv 2:1 SCJ movement > 90° ABD GHJ ABD & STJ UR/Pro/Elv 2:1 GHJ LR SCJ/ACJ ➔posterior rotation clavicle Cervicothoracic spine extension Scapulohumeral Rhythm Coordinated movement of ALL of the jts within shoulder complex requires synergy/coupling of several muscles working simultaneously to steer arthrokinematics & create movement Coordinated SHR reliant on force couples  STJ movement with GHJ movement ABD/F GHJ + ADD/E GHJ + UR/elv/pro DR/dep/ret STJ STJ ≠ their individual actions, BUT movement from combination of muscle forces + gravity Middle Traps Optimal Scapulohumeral Rhythm Scapula movement from 45º - 110º GHJ abduction Pathology: Abnormal Scapulohumeral Rhythm Shoulder 4  Lecture Sub-Sections Shoulder: 1 Joints: Glenohumeral Joint (GHJ) + labrum Structure, Ligaments, Pathology Shoulder: 2 Joints: Sternoclavicular Joint (SCJ); Acromioclavicular Joint (ACJ); Scapulothoracic Joint (STJ); Cervicothoracic spine Structure, Ligaments, Pathology Shoulder: 3 Shoulder complex ROM & Scapulohumeral rhythm Shoulder: 4 Muscles that move & stabilise scapula Attachments/action/function Strength/stretch, Pathology Shoulder: 5 Muscles that move & stabilise GHJ Attachments/action/function Strength/stretch, Pathology Shoulder: 6 Rotator Cuff Muscles Attachments/action/function Strength/stretch & Pathology Muscles that move & stabilise the scapula Attachments: Vertebral Column (VC) &/or rib cage → scapula Vital for optimal postural alignment & movement of scapula, GHJ & cervical spine Improper fxn → poor arthrokinematics GHJ Trapezius Serratus Anterior Rhomboids Levator Scapulae Pec minor Trapezius Att: med/post aspect occipital bone & spinous processes of C1-T12 → sup aspect lat 1/3 clavicle & post. aspect of the acromion and spine of scapula UPPER (UT) (superior): Action: STJ UR/Elv/Ret Fxn: – PM STJ UR/Pro/Elv (as GHJ ABD & F) with serratus anterior (SA) & LT – PM elv STJ – Antag STJ depression (to LT) – Accessory muscle inspiration MIDDLE (MT): Action: STJ Ret Fxn: – PM DR/Ret/Dep STJ (as GHJ ADD & E) with rhomboids – PM STJ retraction – Antag STJ protraction – Stab scap “anchor scap” LOWER (LT) (inferior): Action: STJ UR/Dep/Ret Fxn: – PM STJ UR/Pro/Elv (as GHJ ABD & F) with serratus anterior (SA) & UT – PM dep STJ – Antag STJ elevation (to UT) Rohan, J., Yokochi, C & Lutjen-Drecoll, E, 2002  Serratus Anterior (SA) Att: ant/lat aspect external surface Ribs 1-8 → anterior aspect of entire medial border of the scapula Action: STJ protraction (upper & fibres LR/elv & lower fibres MR/dep) Fxn: – PM STJ UR/pro/elv (as GHJ ABD & F with UT & LT) – PM STJ protraction – Antag STJ retraction (to MT/Rhom) – Accessory muscle inspiration McGraw-Hill, 2006 McGraw-Hill, 2006 Co-contraction to stabilise STJ Force couple SA, UT, LT ABD/F GHJ + UR/elv/pro STJ Serratus Anterior strength Resisted STJ protraction Resisted STJ protraction (with GHJ F or ABD) Eccentric contraction: controls gravity induced STJ retraction (with GHJ E or ADD) – scapula stabiliser  Rhomboids Att: SP C7-T5 → posterior aspect medial border scapula Action: STJ Ret/DR/Elv Fxn: – PM DR/Ret/Dep STJ (as GHJ ADD & E) with MT & force of gravity on UL – PM hand up back (STJ DR/Ret (with lev scapulae & pec minor) – Antag STJ protraction (to serratus anterior) Hand up back: downward rotation & retraction scapula Hand Up Back (HUB) Hand Down Back (HDB) GHJ: E/ADD/MR GHJ: F/ABD/LR STJ: DR/Ret/Dep STJ: UR/Pro/Elv McGraw-Hill, 2006 ROM: Hand Up Back Force couple Rhom, MT with lev scap & pec minor ADD/E GHJ + DR/dep/ret STJ ≠ their individual actions, BUT movement from combination of muscle forces + gravity Middle Traps Rhomboids/Middle traps strength Resisted STJ protraction (with GHJ E or ADD)  Levator Scapulae Att: Transverse Processes (TP) C 1-4 → superior angle & superior aspect medial border scapula Action: STJ Elv/DR/Ret Fxn: – PM hand up back = DR/Ret (with rhomboids & pec minor) – Ass. STJ elv (with UT) – Ass. STJ ret (with Rhom) – Antag STJ dep (with LT)  Pectoralis Minor Att: Ant/sup aspect of the external surface ribs 3-5 (close to costal cartilage → coracoid process Action: STJ DR/Elv/Pro Fxn: – PM STJ DR/Elv/Pro – PM hand up back = DR/Ret (with lev scap minor & rhomboids) – Ass. STJ elv – Accessory muscle inspir Tight Pectoralis Minor & Posture Pectoralis minor stretches Focus on scapulae retraction & muscle fibre direction  Subclavius Att: Jxn Rib1 & Costal Cartilage→ inf middle 1/3 clav Action: depress clavicle Fxn: – Stab clav against forces that tend to elvevate it – Accessory muscle inspir Netter, 2003 Shoulder 5  Lecture Sub-Sections Shoulder: 1 Joints: Glenohumeral Joint (GHJ) + labrum Structure, Ligaments, Pathology Shoulder: 2 Joints: Sternoclavicular Joint (SCJ); Acromioclavicular Joint (ACJ); Scapulothoracic Joint (STJ); Cervicothoracic spine Structure, Ligaments, Pathology Shoulder: 3 Shoulder complex ROM & Scapulohumeral rhythm Shoulder: 4 Muscles that move & stabilise scapula Attachments/action/function Strength/stretch, Pathology Shoulder: 5 Muscles that move & stabilise GHJ Attachments/action/function Strength/stretch, Pathology Shoulder: 6 Rotator Cuff Muscles Attachments/action/function Strength/stretch & Pathology Muscles that move & stabilise the GHJ Attachments: scapula, clavicle, sternum & ribs → humerus Directly move the GHJ Deltoid Pectoralis Major Coracobrachialis Biceps Triceps Latissimus Dorsi/Teres Major  Deltoid Att: ant/sup aspect of lat. 1/3 clav, acromion process & spine of scapula → deltoid tuberosity 3 parts: Anterior: Action: GHJ ABD/F/MR Fxn: – PM GHJ ABD/F/MR – Ass GHJ ABD or F or MR – Ass horizontal Add (F) – During Abd/F GHJ: – F/MR of ant. deltoid neut E/LR of post. Deltoid – co-contraction ant & post deltoid stab GHJ in transverse plane (MR & LR) – co-contraction ant & post deltoid stab GHJ in sagittal plane (F & E) Netter, 2003 Posterior: Action: ABD/E/LR GHJ Fxn: – PM GHJ ABD/E/LR – Ass GHJ ABD or E or LR – Ass horizontal Abd (E) – During Add/E GHJ: – F/MR of ant. deltoid neut E/LR of post. Deltoid – co-contraction ant & post deltoid stab GHJ in transverse plane (MR & LR) – co-contraction ant & post deltoid stab GHJ in sagittal plane (F & E) Middle: (multipennate) Action: ABD GHJ Fxn: – PM ABD – co-contraction mid deltoid with pec major or lat D stab GHJ in coronal plane (ABD & ADD) McGraw-Hill, 2006 Deltoid strength Resisted shoulder abduction Eccentric contraction: controls gravity induced shoulder ADD  Workshop Activity Describe body position, shoulder & elbow Describe where the band is anchored relative to the ROM during the concentric phase (i.e. body, body position, shoulder & elbow ROM during where the dumbbell is lifted) the concentric phase (i.e. where elastic resistant band is stretched) Shoulder ROM Band Anchored Body position Elbow ROM Shoulder Position Elbow ROM Deltoid stretch Posterior shoulder F/ADD Anterior deltoid shoulder E/ADD=  Pectoralis Major Att: ant surface medial 2/3 clavicle, anterior aspect sternum & costal cartilage of RIBS 1-7 to the lateral lip intertubercular groove (ant & prox humerus) & aponeurosis of external oblique muscle Action: Clav head: GHJ F/MR Action: Sternal head: GHJ F/ADD/MR Fxn: – Clav head: PM GHJ F – Sternal head: Ass. GHJ F, PM GHJ F/Add/MR & Ass GHJ MR – Ass. horizontal Add (F) (with ant. deltoid – co-contraction pec major & lat D stab GHJ in sagittal plane (F & E) Netter, 2003 Pec strength Resisted shoulder adduction Eccentric contraction: controls gravity induced shoulder ABD Resisted shoulder F/ADD/MR  Pec stretch Commonly stretched with pec minor GHJ E/ABD/LR Focus on muscle fibre direction & GHJ  Coracobrachialis Att: coracoid process of scapula → medial aspect of the mid-shaft humerus Action: weak GHJ F/Add Fxn: – Ass. GHJ F – Ass. GHJ ADD McGraw-Hill, 2006  Biceps Brachii Prox Att: (2 heads): – Long head: superior glenoid tubercle & labrum (intracapsular) – Short: coracoid process Distal Att. → radial tuberosity (ant/med aspect of the prox. radius) action: elbow F, PRUJ supination, GHJ F Fxn: – Ass elbow F, Ass PRUJ supination, Ass GHJ F – PM elbow F, PRUJ supination OR GHJ F with elbow F/supination – antag GHJ E, elbow E – Stabilise elbow joint (with brachialis) in sagittal plane with triceps > Torque & moment arm in 90°F McGraw-Hill 2006 McGraw-Hill, 2006 McGraw-Hill, 2006 Biceps strength Resisted elbow F + PRUJ supination Eccentric contraction: controls gravity induced elbow E in supination Biceps stretch GHJ E + elbow E Biceps brachii pathology SLAP lesion: tear of the Superior Labrum from Anterior to Posterior High energy trauma or overuse injury from overhead throwing sports Latissimus Dorsi Att: Spinous Process (SP) T6-12, SP L1-S4 via thoracolumbar fascia with & post aspect iliac crest & inf angle scapula & ribs 9-12 → floor intertubercular groove (ant/prox humerus) Action: GHJ E/ADD/MR Fxn: – PM GHJ E/ADD/MR (with teres major) – PM. GHJ ADD (with pec major) – Ass. GHJ MR – Ass. horizontal Add (E) (with post. deltoid – co-contraction lat D & pec major stab GHJ in sagittal plane (F & E) – Ass. ret/dep of STJ (when humerus (upper limb) is fixed Rohan, J., Yokochi, C & Lutjen-Drecoll, E, 2002  Teres Major Att: inf angle posterior surface scapula → medial lip of the intertubercular groove (ant/prox humerus) Action: GHJ E/ADD/MR Fxn: – PM E/ADD/MR (with lat D) – Ass GHJ Add or MR McGraw-Hill, 2006 Lat Dorsi strength Resisted GHJ ADD/E/MR “Lat Pull Down”  Workshop Activity Describe body position, shoulder & elbow Describe where the band is anchored relative to the ROM during the concentric phase (i.e. body, body position, shoulder & elbow ROM during where the dumbbell is lifted) the concentric phase (i.e. where elastic resistant band is stretched) Shoulder ROM Band Anchored Body position Elbow ROM Shoulder Position Elbow ROM Lat Dorsi stretch GHJ ABD/F + L/Sp F  Triceps brachii Prox Att (3 heads): – long: infraglenoid tubercle (infer. to glenoid fossa) – lat: lat aspect of the prox ½ of the post. shaft humerus (prox to radial groove) – med: med aspect of the distal ½ of the post. shaft humerus (distal to radial groove) – Distal Att → olecranon process ulna Netter, 2003 Action: LONG HEAD: GHJ E/ADD & elbow E Action: MED & LAT HEAD: Elbow E Fxn: – LONG HEAD: PM E/ADD GHJ, elbow E (long head) & Ass. elbow E & Ass. GHJ E & Ass. GHJ ADD – MED & LAT HEAD: PM elbow E; Antag elbow F 1. Long head; 2: Lateral head; 3. Medial head Triceps strength Eccentric contraction: controls gravity induced elbow F Resisted elbow extension & shoulder extension Triceps stretch elbow F + GHJ F  Workshop Activity PM ASS Mover STJ upward rotation, protraction, and elevation (GHJ abduction 0°-110° abduction with elastic resistant band – stretching band) STJ downward rotation, retraction, and depression during the exercise in image below (GHJ abduction 110°-0° abduction with elastic resistant band – controlling elastic recoil of band STJ downward rotation, retraction and depression during exercise in image below (GHJ adduction 170°-90° abduction - stretching band) STJ retraction during exercise in image below (GHJ extension from 0°- 45° with hand weights) Shoulder 6  Lecture Sub-Sections Shoulder: 1 Joints: Glenohumeral Joint (GHJ) + labrum Structure, Ligaments, Pathology Shoulder: 2 Joints: Sternoclavicular Joint (SCJ); Acromioclavicular Joint (ACJ); Scapulothoracic Joint (STJ); Cervicothoracic spine Structure, Ligaments, Pathology Shoulder: 3 Shoulder complex ROM & Scapulohumeral rhythm Shoulder: 4 Muscles that move & stabilise scapula Attachments/action/function Strength/stretch, Pathology Shoulder: 5 Muscles that move & stabilise GHJ Attachments/action/function Strength/stretch, Pathology Shoulder: 6 Rotator Cuff Muscles Attachments/action/function Strength/stretch & Pathology  Rotator Cuff Muscles Deepest muscles GHJ Function: Dynamic stab GHJ, – strategic position around GHJ, large trans-articular component STABILISE GHJ – Work as team to steer HOH within glenoid fossa (centralization HOH) during static & dynamic postures – prevent biomechanical impingement & prevent excessive translations of HOH in glenoid fossa Action = rotation – External rotation: infraspinatus, teres minor & supraspinatus – Internal rotation: subscapularis Tendons capsular Anterior Posterior Rotator Cuff Function Rotator Cuff Function Guide Arthrokinematics Stability  Rotator Cuff Function Guide Arthrokinematics Maintain centralisation HOH in glenoid fossa Supraspinatus: “roll” of HOH in glenoid fossa Infraspin/teres minor/subscapularis: provide inferior shear force to balance superior shear force deltoid during GHJ abduction  Supraspinatus Att: supraspinatus fossa → superior facet on the greater tubercle humerus & superior aspect GHJ capsule Action: LR GHJ Fxn: – Stab GHJ (transarticular) Maintain articular surfaces in contact Limits creep of the coracohumeral ligament (due to weight of upper limb) Stab superior aspect GHJ joint capsule – Arthokinematics GHJ: guide roll and glide of HOH on glenoid (with RC group) – Force couple with deltoid during ABD GHJ – Ass mover GHJ LR McGraw-Hill, 2006 Pathology Supraspinatus  Pathology Supraspinatus Torn Rotator Cuff Acute tear Degenerative tear Clinical Strength test: Supraspinatus tear Empty can test & Full can test Compare bilateral resisted elevation of GHJ in 90º F/ABD (scapular plane) with: i. GHJ MR “emptying can” ii. GHJ LR “full can” Positive test: weakness & localised pain Infraspinatus Att: infraspinatus fossa → middle posterior facet on the greater tubercle humerus & posterior aspect GHJ capsule Action: GHJ LR Fxn: Fxn: – Stab GHJ (transarticular) Maintain articular surfaces in contact Stab posterior aspect GHJ joint capsule – Arthokinematics GHJ: provide inferior shear HOH with rest of RC – PM GHJ LR with teres minor – Antag MR  Teres Minor ATT: superior 2/3 lateral border scapula on the dorsal surface → inferior & posterior facet on the greater tubercle humerus & posterior aspect GHJ capsule Action: LR GHJ Fxn: – Stab GHJ (transarticular) Maintain articular surfaces in contact Stab posterior aspect GHJ joint capsule – Arthokinematics GHJ: provide inferior shear HOH with rest of RC – PM GHJ LR with infraspinatus – Antag MR Clinical Strength test: Infraspinatus/teres minor tear Resisted ER: Compare bilateral isometric LR strength with shoulder neutral position and elbow F 90º) (i.e., LR = external rotation) Positive test: weakness & localised pain  Subscapularis Att: subscapula fossa (costal surface) scapula → lesser tubercle humerus (ant/prox humerus) & anterior aspect GHJ capsule Action: GHJ MR Fxn: – Stab GHJ (transarticular) Maintain articular surfaces in contact Stab anterior aspect GHJ joint capsule – Arthokinematics GHJ: guide roll and glide (inferior shear) of HOH on glenoid (with rest of RC) – PM GHJ MR – Antag LR McGraw-Hill, 2006 Clinical Strength test: Subscapularis tear Lift-off test: Examiner positions GHJ in end of range MR (~ 20º ABD - plane of scapula), patient lift hand off back (resist MR, i.e., = internal rotation) Positive test: weakness to lift hand off back (note subscapularis in shortened length - (length/tension) Rotator Cuff Strength Infraspin/teres minor: Subscapularis: Resisted LR GHJ Resisted MR GHJ Rotator Cuff strength Stability GHJ High load (weight bearing), High speed  Workshop Activity 1 3 4 NUMBER MATCH THE EXS WITH THE MUSCLE (CONCENTRIC) Subscapularis using the hand weights 2 Subscapularis using elastic band infraspinatus & teres minor using the hand weights infraspinatus & teres minor using elastic band