Shoulder Complex - Lecture Flashcards
What are the functions of the shoulder complex?
- To position the hand in space and as a result perform fine motor actions.
- Suspend the upper extremity
- To provide a fixed point so the upper extremity can move.
- to serve as a fulcrum for arm elevation.
Describe scaption.
the “backwards windshield whipper movement” of the scapula. Lateral, superior, and anterior movement of the scapula.
Name the bones and the joints of the shoulder complex.
Bones: Humerus, clavicle, scapula
Joints: Sternoclavicular, Acromial Clavicular, Glenohumeral
Psudojoint: Scapulothoracic articulation
What strucutre in the glenohumeral joint is vital to enlarging the glenoid fossa, thereby stabilizing the GH joint?
The Labrum:
The labrum of the GH joint increases the depth of the glenoid fossa by about 50%. (think of it like a suction cup around the humeral head).
What may we expect to see with a torn labrum?
Fluid Build-up (joint effusion)
Instability
Dislocation
Describe how the scapula sits on the thorax.
30° to the frontal plane,
3° superiorly relative to the transverse plane
20° forward in the sagittal plane
Name the muscles that attach to the scapula.
- Trapezius
- Levator Scap
- Biceps Brachii
- Rhomboid Major and Minor
- Lattissmus Dorsi
- Supraspinatous
- Infraspintous
- Deltoid
- Subscapularis
- Coracobrachilais
- Pectorialis Minor
- Serratus Anterior
- Long Head of the Triceps
- Teres Major
- Teres Minor
- Omohyoid
Which of the muscles that attach to the scapula actually act on the scapula to assist with movement or support?
1) trapezius
2) rhomboids
3) levator scapulae
4) serratus anterior
5) Latissimus Dorsi
6) Pectoralis Minor
Genearlly, what is the funtion of the other muscles that attach to the scapula?
- To stabilize the humerus
2. To move the glenohumeral joint
What does morphology mean?
The shape of
What is important about the morphology of the acromion?
There are 3 difference possible shapes
- flat undersurface
- Convex undersurface
- Hooked undersurface
When does the acromion predispose a patient to shoulder pathology? Why?
When the acromion is hooked it is more likely to rub/fray one of the tendons that run underneath it.
What are the attachments of the joint capsule in the glenohumeral joint.
Laterally: to the anatomical neck of the humerus
Medially: peripheral glenoid fossa and its labrum
Describe the strength of the joint capsule in relation to the age of the patient.
Inverse relationship:
The older the pt the weaker the joint capsule
Where in the shoulder is synovial fluid normally found?
within the joint capsule from the labrum to the neck of the humerus.
What other infection is herpes zoster associated with?
chicken pox
True or False: Herpers zolster never presents unilaterally.
False: ALWAYS unilateral
What are the characteristics of herpes zolster?
Sever Neuralgic pain Chills/fever malaise and lathergy eythrema of the skin tender regional lymph nodes vesicles apear apon the dermatomes when vesicles burst they are slow to heal.
What information that can be obtained from the history will be related to Shingles?
History of Chicken pox
Current stress/ reasons for a weakened immune system.
What pathology is associated with “waiter’s tip” position?
Erb’s Palsy
AKA Erb-Duchenne Paralysis
What nerve roots are associated with Erb’s Palsy?
C5-C6: upper brachial plexus.
What causes Erb’s Palsy?
Depression of the shoulder
- birth trauma
- later in life
What characteristics do you expect to see in patients with Erb’s Palsy?
internally rotated and adducted on the effected arm
biceps reflect is lost with muscle wasting
motion and the hand and elbow are still present
waiters tip position
What nerve roots are associated with Klmpke’s Palsy?
Lower cervical (C8-T1)