Chapter 1: Functional Anatomy and Biomechanics - Shoulder Region

Card Set Information

Chapter 1: Functional Anatomy and Biomechanics - Shoulder Region
2015-03-08 19:09:14
Shoulder Region
NPTE: Chapter 1
Show Answers:

  1. Humerus
    • Proximal end is approximately half a spheroid
    • Articular surface covered by hyaline cartilage
    • Head is retroverted 20-30 degrees
    • Longitudinal axis of head is 135 degrees from axis of neck
  2. Scapula
    • Sits over 2nd-7th ribs
    • Costal and dorsal surfaces
    • Three angles = medial, superior, and lateral
    • Lateral angle bears glenoid fossa (faces anteriorly, laterally, and superiorly)
    • Rear shape of fossa allows for freer ROM in abd and flex
    • Orientation of glenoid fossa places true abd at 30 degrees ant to frontal plane
  3. Clavicle
    • Extends laterally and links manubrium to acromion
    • Connects shoulder complex to axial skeleton
  4. Shoulder Region: Arthrology
    • GH Joint: convex head articulates with concave glenoid fossa (very shallow)
    • SC Joint: convex (sup/inf) and concave (ant/post), articulates with reciprocal shape of sternum (both articulations covered with fibrocartilage)
    • AC Joint: plane joint with relatively flat surface
    • Scapulothoracic Joint: a "clinical" articulation
  5. Capsule
    • Attaches medially to glenoid margin, glenoid labrum, &coracoid process
    • Attaches laterally to humeral anatomical neck and descends approx 1 cm on the shaft
    • Supported by tendons of supraspinatus, infraspinatus, teres minor, subscap, and long head of triceps
    • Inferiorly, capsule is least supported and most lax
  6. Coracohumeral Ligament
    • Base of coracoid process --> greater and lesser tubercle of humerus
    • Primary function = reinforce biceps tendon, reinforce superior capsule, and prevent caudal dislocation of humerus
    • Taught with ER
  7. Coracromial Ligament
    • Strong triangular ligament, runs from coracoid --> acromion
    • Not a true ligament - connects 2 points of same bone
  8. Glenohumeral Ligaments
    • 3 bands (sup, middle, and inf)
    • Located on ant GH joint
    • Reinforce ant GH capsule
  9. Transverse Humeral Ligament
    • Broad band passing over bicipital groove
    • Acts as retinaculum for long biceps tendon
  10. Glenoid Labrum
    • Fibrocartilaginous ring that deepens the glenoid fossa
    • Attached to capsule superiorly & inferiorly as well as to the long head of the biceps superiorly
    • Internal surface covered with articular cartilage (thicker peripherally and thinner centrally)
    • Aids in lubrication and serves to protect the joint
  11. Bursae
    • Multiple found within this region
    • Primary bursae involved in pathology = subacromial bursa (between deltoid & capsule; also runs under acromion and coracromial ligament and between supraspinatus tendon)
  12. GH Arthrokinematics/Osteokinematics
    • At about 75 degrees of elevation, ER (conjunct rotation) occurs
    • Prevents compression of greater tubercle against acromion
  13. Scapulohumeral Rhythm
    • With 180 degrees of abd, there is a 2:1 ratio of movement (120 at GH, 60 at scapulothoracic)
    • 1st 30-60 degrees of elevation occurs mainly in GH joint
  14. Requirements of Full Elevation
    • Scapular stabilization
    • Inf glide of humerus
    • ER of humerus
    • Rotation of clavicle at SC joint
    • Scap abd and ER of AC joint
    • Straightening of thoracic kyphosis