Biomechanics of Shoulder joint 04

Shoulder girdle = scapula and clavicle

Shoulder joint (glenohumeral joint) = scapula and humerus

1. THEGLENOHUMERAL(GH)JOINT
THESHOULDERJOINT

2. CLARIFICATIONOFTERMS
•Shouldergirdle=scapulaandclavicle
•Shoulder joint(glenohumeraljoint)=
scapulaandhumerus

3. Anatomy

5. OSTEOLOGYOFTHEGHJOINT(BONES)
•Scapula
•Glenoidfossa
•Glenoidlabrum
•Subscapularfossa
•Infraspinousfossa
•Supraspinousfossa
•Axillaryborder
•Acromionprocess

6. (Axillary)
(Vertebral)
Scapula(Dorsalaspect)

7. (Axillary)
(Vertebral)

8. OSTEOLOGYOFTHEGH
JOINT(BONES)…CONT
•Humerus
•Head
•Surgicalneck
•Anatomicalneck
•Shaft
•Greatertubercle
•Lessertubercle
•Deltoidtuberosity
•Bicipitalgroove
•Bicipitalridges

9. Intertuberculargroove
(Bicepitalgroove)
(Posterioraspect)

10. IntertubercularGroove(bicepitalgroove)
DeltoidTuberosity
AnatomicalNeck

11. JOINTSTRUCTUREOFTHEGHJOINT
Ballandsocketjoint
Movementinallthreeplanes(3degreesof
freedom)
Articulationbetweenthehumeralheadofthe
humerusandtheglenoidfossaofthe
scapula
Oneofthemostmovablejointsinthebody
and,consequently,onethestable.

12. JOINTMOVEMENTOFTHEGHJOINT
•Osteokinematics
•Flexionand Extension
•Hyperextension
•Abduction
•Adduction
•Medialrotation(internalrotation)
•Lateralrotation(externalrotation)
•Horizontalabduction
•Horizontaladduction
•Circumduction

13. VISUALEXERCISE
•Watchyourpartnerperformthefollowing
movementsandguesstimatethedegreesof
motionforeachofthefollowing:
•Shoulderflexion:
•Shoulderhyperextension:
•Shoulderabduction:
•Shoulderinternalrotation:
•Shoulderexternalrotation:

14. JOINTMOVEMENTOFTHEGH
JOINT…CONT
Arthrokinematics
•Concave-convex rule
•Theconvexhumeralheadmoveswithintheconcave
glenoidfossa
•Theconvexjointsurface(humeralhead)movesina
directionoppositetothemovementofthebodysegment
(humeralshaft)
•Flexion–humeralheadglides
•Abduction–humeralheadglides
•Extension–humeralheadglides
•Adduction–humeralheadglides
•Internalrotation–humeralheadglides
•Externalrotation–humeralheadglides

15. JOINTMOVEMENTOFTHEGH
JOINT…CONT
•Arthrokinematics
•Thearticularsurfaceofthehumeralheadis
greaterthan thatoftheglenoidfossa
•Ifthehumeralheadsimplyrotatedintheglenoid
fossa,itwouldrunoutofarticularsurfacebefore
fullabductionoccurred
•So,asabductionoccurs,thehumeralheadrolls
acrosstheglenoidfossaandglidesinferiorly
(thankstotherotatorcuff)
•Completeabductioncanoccuronlywithfull
externalrotation

16. SUPPORTINGSTRUCTURESOFTHEGH
JOINT
•Rotator cuff
•SITSmusclessurroundhumeralheadandactivelyholdit
againsttheglenoidfossa
•Capsular ligaments
•Relativelyloosecapsuleattachestherimoftheglenoidfossa
andanatomicneckofthehumerus
•Coracohumeral ligaments
•Connectscoracoidprocessandanteriorsideofgreater
tubercle
•Glenoid labrum
•Afibrocartilaginousringthatencirclestherimoftheglenoid
fossa,deepeningthesocketandsealingthejoint
•Long head of the Biceps
•Theproximalportionofthetendonwrapsaroundthe
superioraspectofthehumeralhead,providinganterior
stability

17. MYOLOGYOFTHEGHJOINT(MUSCLES)
•Deltoid
•Pectoralismajor
•Latissimusdorsi
•Teresmajor
•Supraspinatus
•Infraspinatus
•Teresminor
•Subscapularis
•Coracobrachialis
•Bicepsbrachii
•Tricepsbrachii,longhead

18. Anterior
Deltoid:Anterior
Origin Anteriorsurfaceofthelateralaspect
oftheclavicle
Insertion Deltoidtuberosityofthehumerus
Action Shflexion,HADD,ShIR,ShABD
InnervationAxillaryn.

19. …strengthenthe anteriordeltoid
•Concentrically?

20. MiddleDeltoid
Deltoid:Middle
Origin Superiorlateralsurfaceof
theacromion
Insertion Deltoidtuberosityofthe
humerus
Action ShABD,Shflexion
Innervation Axillaryn.

21. Deltoid:Posterior
Origin Spineofthescapula
Insertion Deltoidtuberosityofthe
humerus
Action Shextension,HABD,ShER
InnervationAxillaryn.

22. PectoralisMajor
Origin Clavicular portion:anteriormargin
ofthemedialportionofthe
clavicle
Sternal portion:lateralmarginof
themanubriumandbodyofthe
sternumandcartilageofthefirst
6-7ribs
InsertionCrestofthegreatertubercleof
thehumerus
Action Clavicular:Shoulderflexion,IR
andHorizADD
Sternal:ShIR,ShADD,Sh
extensiontoanatomicposition
InnervationClavicular:lateralpectoraln.
Sternal:lat&medialpectoraln.

23. …stretch the pectoralismajor?
…strengthen the pectoralismajor
eccentrically?

24. LatissimusDorsi
Origin Thoracolumbarfascia,spinousprocesses
oflowerthoracicandlumbarvertebrae,
posterioriliaccrest,lower4ribsandinferior
angleofscapula
Insertion Floorofintertuberculargrooveofhumerus
Action ShADD,Shextension,ShIR,scapular
depression
InnervationThoracodorsaln.
“tidbit” Necessary for “crutchwalking” and
transfers!

25. …stretchthe latissimusdorsi?

26. TeresMajor
Origin Inferiorangleofthescapula
Insertion Crestofthelessertubercleofthehumerus
Action ShADD,Shextension,ShIR
InnervationLowerscapularn.

27. SITS
•Supraspinatus
•Infraspinatus
•TeresMinor
•Subscapularis

28. Supraspinatus
Origin Supraspinousfossaofthe
scapula
Insertion Greatertubercleofthehumerus
Action ShABD,stabilizationoftheGH,
slightER
InnervationSuprascapularn.
“Tidbit” Oneoftherotatorcuff
muscles

29. Infraspinatus
Origin Infraspinousfossaofthe
scapula
Insertion Greatertubercleofthe
humerus
Action ShER,stabilizationoftheGH
joint
Innervation Suprascapularn.
“tidbit” Oneoftherotatorcuff
muscles

30. TeresMinor
Origin Posteriorlateralborderof
thescapulanearthe
inferiorangle
Insertion Greatertubercleofthe
humerus(inferiortothe
infraspinatus)
Action ShER,stabilizationofthe
GHjoint
InnervationAxillaryn.

31. Subscapularis
Origin Subscapularfossaofthe
scapula
Insertion Lessertubercleofthe
humerus
Action ShIR,stabilizationoftheGH
joint
InnervationUpperandlowersubscapular
n.
“tidbit” Oneoftherotatorcuff
muscles

32. Coracobrachialis
Origin Coracoidprocessofthescapula
Insertion Medialaspectoftheproximalshaftof
thehumerus
Action AssistswithShflexion&add
Innervation Musculocutaneousn.

33. Biceps
Brachii
BicepsBrachii
Origin Long head:supraglenoidtubercleof
glenoidfossa
Short head:coracoidprocessofthe
scapula
InsertionRadialtuberosityoftheradius
Action Shflexion,elbowflexion,forearm
supination
InnervationMusculocutaneousn.
“tidbit” Theactionsofthebicepsbrachiiare
“perfect” in combination for opening a
bottleof wine.“The Corkscrew effect”

34. …strengthen the biceps brachii
isometrically?
…stretch the biceps brachii?

35. LongHeadoftheTricepsBrachii
Origin Infraglenoidtubercleofthe
scapula
Insertion Olecranonprocessoftheulna
Action Shextension,elbowextension
Innervation Radialn.

36. MYOLOGYOFTHEGHJOINT
(MUSCLES)…CONT
•Anatomical Relationsips
•Musclesthatstabilizearedeeptomusclesthatmove.
•Therefore,glenohumeraljointmusclesaresuperficialto
shouldergirdlemuscles
•Deltoid:formsasuperficialcapovertheanterior,lateral
andposteriorsidesoftheshoulder
•Anteriorly,pectoralismajorcoversmostofthesuperficial
chestwall
•Bicepsbrachiiandtricepsbrachiiencompassmostofthe
anteriorandposteriorarm,respectively
•Ifthetrapeziuswereremoved,youwouldseethe
supraspinatusabovethescapularspineandin
descendingorder,theinfraspinatus,teresminorand
teresmajorbelowthescapularspine
•Thelatissimusdorsicoversthelumbarandlowerthoracic
regionoftheback

37. MYOLOGYOFTHEGHJOINT
(MUSCLES)…CONT
•AnatomicalRelationsips

38. MYOLOGYOFTHEGHJOINT
(MUSCLES)…CONT
•SummaryofMuscle Action:
Action Muscles
Flexion Anteriordeltoid,pectoralismajor(clavicular)
Extension Posteriordeltoid,lattisimusdorsi,teresmajor,
pectoralismajor(sternal)
Hyperextension Latissimusdorsi,posteriordeltoid
Abduction Deltoid,supraspinatus
Adduction Pectoralismajor,teresmajor,latissimusdorsi
HorizontalabductionPosteriordeltoid,infraspinatus,teresminor
HorizontaladductionPectoralismajor,anteriordeltoid
Lateralrotation Infraspinatus,teresminor,posteriordeltoid
Medialrotation Latissimusdorsi,teresmajor,subscapularis,
pectoralismajor,anteriordeltoid

39. MYOLOGYOFTHEGHJOINT
(MUSCLES)…CONT
•SummaryofMuscle Innervation:
Lippert,p143
Muscle Nerve Segment
Subscapularis Upperandlowersubscapular C5,C6
Teresmajor Lowersubscapular C5,C6
Pectoralismajor Lateralandmedialpectoral C5,C6,C7&C8,T1
Latissimusdorsi Thoracodorsal C6,C7,C8
Supraspinatus Suprascapular C5,C6
Infraspinatus Suprascapular C5,C6
Deltoid Axillary C5,C6
Teresminor Axillary C5,C6
Coracobrachialis Musculocutaneous C6,C7
Biceps Musculocutaneous C5,C6
triceps radial C7,C8

40. COMMON SHOULDERPATHOLOGY
•ACseparation:
•Fractures:
•Shoulderdislocationandsubluxation:
•Impingement:
•AdhesiveCapsulitis:
•RotatorCuffTear:
•BicipitalTendonitis:

41. PINTHETAILONTHEDONKEY
•Pointtothe…
•Shoulderflexors
•Shoulderextensors
•Shoulderabductors

42. Whatupperextremitymuscles
canyouidentifyonhim?

43. AgainstGravity
Position
Gravity
Eliminated
Position
GravityAssisted
Position
Shoulder
Extensors
Shoulder
Abductors
ShoulderInternal
Rotators

44. Duringapushup,thereisaraisingofthebody
andaloweringofthebody. Identify
whattypeofcontractionthemuscleisdoing
duringeachcomponentofapushup:
•Isometric
•Concentric
•Eccentric
•Nocontraction

45. Raisingthebody Loweringthebody
Bicepsbrachii
Tricepsbrachii
Protractors
Retractors
Abdominals