Proximal Humerus Anatomy Quiz

Proximal Humerus Anatomy

• Largest and longest bone in the upper extremity
• Approximately 1/5 of an adult's height
• Articulates with the scapula at the shoulder joint
• '
• The most proximal part of the humerus is a rounded portion called the head '
• ' Slightly constricted portion below the head is the anatomic neck
• The process directly below the anatomic neck on the anterior surface is the lesser tubercle
• Larger lateral process is the greater tubercle where the pectoralis major and supraspinatus muscles attach
• Deep groove between the two tubercles is the intertubercular groove (bicipital groove)
• The area below the head and tubercles is the surgical neck
• Distal to the surgical neck is the body (shaft)
• Deltoid tuberosity is a rough raised elevation along the anterolateral surface of the body where the deltoid muscle attaches

Joints

• Scapulohumeral joint (glenohumeral or shoulder joint) 'h
• Elbow joint '

Learning Outcomes

• Identify the following joints on an image of the upper extremity:
  • Acromioclavicular joint
  • Shoulder joint
  • Sternoclavicular joint
• Identify the following parts and prominences on an image or skeleton:
  • Scapula
    • Head
    • Neck
    • Body
    • Glenoid cavity
    • Spine
    • Acromion
    • Coracoid process
    • Angles: Medial, Superior, and Inferior
    • Borders: Superior, Axillary, and Vertebral
    • Scapular Notch

Let's Review – Proximal Humerus

• The two neck names and where they are located are:
  • Anatomical neck: Located below the head
  • Surgical neck: Located below the lesser and greater tubercle
• Lesser tubercle is the smaller more medial tubercule
• Greater tubercle is the larger more lateral tubercule
• Intertubercular sulcus/groove (bicipital groove) is the groove that separates the tubercules
• Deltoid tuberosity is the name of the rough elevation on the body of the humerus
• Deltoid muscle attaches to the deltoid tuberosity
• Pectoralis major and supraspinatus muscles attach to the greater tubercle
• The other two names that refer to the shoulder joint are glenohumeral joint and scapulohumeral joint

Shoulder Girdle

• Consists of 2 bones:
  • Clavicle
  • Scapula
• Function of the two bones is to connect the upper limb to the trunk (axial skeleton)

Scapula Anatomy - Borders

• Forms the posterior part of the shoulder girdle
• Flat, triangular bone
• The scapula has 3 borders:
  • Superior border: Uppermost margin
  • Lateral (Axillary) border: Border nearest axilla
  • Medial (Vertebral) border: Border near the vertebrae

Scapula Anatomy - Angles

• The three corners of the scapula are called angles:
  • Superior angle: High - medial corner of the scapula
  • Inferior angle: Most inferior portion of the scapula
  • Lateral angle (head): Sometimes called head of the scapula, thickest part, ends laterally in a shallow depression called the glenoid cavity (fossa)

Shoulder Joint – Glenohumeral Joint

• Formed by the:
  • Glenoid cavity (fossa) of the scapula
  • Head of the humerus

Scapula Anatomy – Anterior View

• Neck: Constricted area between the head and body of the scapula
• Body (blade): Arched in shape for greater strength, thin flat lower portion of the body is referred to as the Wing or ala
• Costal (Ventral) Surface: Anterior surface of the scapula
• Subscapular fossa: Large depression on the anterior side

Scapula Anatomy – Anterior View

• Acromion: Long, curved process that extends laterally over the head of the humerus
• Coracoid process: Thick, beaklike process that projects anteriorly beneath the clavicle
• Suprascapular notch: Is on the superior border that is partially formed by the base of the coracoid process

Scapula Anatomy – Posterior View

• Posterior surface: Aka dorsal surface
• Spine: Prominent structure on the dorsal surface, starts at the vertebral border as a smooth area and continues laterally to end at the acromion
• Crest of spine: Thickened ridge of the spine
• Spine separates the posterior surface into the:
  • Infraspinous fossa
  • Supraspinous fossa

Scapula Anatomy

• The lateral view of the scapula looks like the letter Y
• The Y is formed by the acromion and coracoid:
  • Acromion extends superior and posteriorly in relation to the glenoid cavity
  • Coracoid is located anteriorly in relation to the joint or glenoid cavity
• Lower portion of Y is the body

Proximal Humerus Rotation

• External Rotation
• Internal Rotation
• Neutral Rotation

Positioning Considerations

• 40 SID
• Grid (greater than 10cm)
• Remove anything that could cause artifacts
• Suspend respiration

Clinical Indications – Shoulder/Scapula

• Degenerative conditions:
  • Osteoporosis
  • Osteoarthritis
• Hill-Sachs defect
• Fractures & Dislocations
• Bursitis

Routine ( Nontrauma) Projections

• AP External Rotation (AP)
• AP Internal Rotation (Lateral)

AP Shoulder: External Rotation

• 40 SID
• GRID
• Patient erect or supine
• Abduct extended arm slightly
• Externally rotate arm (supinate hand) until epicondyles are parallel to IR
• CR – 1 inch inferior to coracoid process

Evaluation Criteria (External Rotation)

• Greater tubercle profiled laterally
• Scapulohumeral joint centered
• Proximal humerus, upper scapula, and clavicle visualized
• Optimal exposure factors

AP Shoulder – Internal Rotation

• 40 SID
• Grid
• Patient erect or supine
• Internally rotate arm (Pronate hand) until epicondyles are perpendicular to IR
• CR – 1 in inferior to coracoid process

Evaluation Criteria (Internal Rotation)

• Lesser tubercle profiled medially
• Scapulohumeral joint centered
• Proximal humerus, upper scapula, and clavicle visualized
• Optimal exposure factors

Special (nontrauma) Projections

• Inferosuperior Axial Projection (Lawrence Method)
• AP oblique projection (Grashey method)

Inferosuperior Axial Projection: Shoulder (Lawrence Method)

• 40 SID
• Position patient supine & shoulder raised about 2 inches from tabletop
• Rotate head toward opposite side
• Abduct arm 90 degrees from body
• Externally rotate arm with palm up
• CR – Directed medially 25-30˚, Centered to axilla & humeral head

Evaluation Criteria (Inferosuperior Axial Projection)

• Lesser tubercle profiled anteriorly
• Humeral head and glenoid fossa profiled
• Optimal exposure factors

AP Oblique Projection: Grashey method

• Glenoid Cavity should be visualized
• 40 SID
• Grid
• Erect or Supine
• Rotate body 35-45˚ toward affected side (posterior oblique)
• CR – Centered to scapulohumeral joint

Evaluation Criteria: Grashey Method (Posterior Oblique)

• Glenoid cavity profiled
• Scapulohumeral joint centered
• Optimal exposure factors

Routine (trauma) Projections

• AP Neutral rotation
• PA Oblique (Scapular Y Lateral)

AP Neutral: Shoulder (Trauma)

• 40 SID
• Grid
• Erect or Supine
• Arm at side in “as is” position
• CR – Mid-scapulohumeral joint

Evaluation Criteria (AP Neutral)

• Greater tubercle superimposed
• Scapulohumeral joint centered
• Optimal exposure factors

PA Oblique-Scapular Y Lateral: Shoulder (Trauma)

• 40 SID
• Grid
• Erect or supine
• Rotate patient into anterior oblique position 45-60˚
• Palpate the superior angle of the scapula & AC joint articulation
• Rotate patient until two points are perpendicular to IR

Evaluation Criteria (Scapular Y Lateral)

• Body of scapula superimposed on end
• Acromion and coracoid processes in profile
• Humeral head and glenoid cavity superimposed
• Optimal exposure factors

Special (Trauma) Projections

• Supraspinatus outlet (Neer method)

Supraspinatus Outlet: Shoulder (Trauma) ’

• Neer Method
• Specifically demonstrates coracoacromial arch for supraspinatus outlet region for possible shoulder impingement
• 40 SID
• Rotate patient into anterior oblique 45-60˚
• CR – angle 10-15˚ caudal centered to pass through humeral head

Evaluation Criteria (Neer Method vs. Scapular Y Lateral Projection:

• Supraspinatus outlet (Neer method) open and in profile
• Demonstrates coracoacromial arch
• Optimal exposure factors

Routine Scapula Projections

• AP
• Lateral

AP Projection: Scapula

• 40 SID
• Erect or supine
• Abduct arm 90˚ and supinate hand
• CR – perpendicular to midscapula, (level of axilla and 2 inches medial from lateral border of patient)
• Orthostatic breathing technique preferred

Evaluation Criteria (AP Projection)

• Entire scapula demonstrated
• Lateral border of scapula free of ribs and lungs
• Optimal exposure factors

Lateral: Scapula - Erect

• Have patient reach a crossed chest and grasp opposite shoulder to demonstrate body of scapula
• Let arm hang by patients' side to demonstrate acromion and coracoid processes
• Rotate patient 45-60˚
• CR – Midvertebral border of scapula

Lateral Scapula- Recumbent

• Patient supine
• Rotate patient till AC joint articulation and superior border of scapula are perpendicular to IR
• CR- midscapula lateral border

Body of Scapula in Profile (Lateral Scapula)

• Borders of scapula superimposed
• Free of superimposition by ribs
• Arm elevated to demonstrate scapular body

Quiz Me

• The projection that would best demonstrate a possible Hill-Sachs defect is the A.Inferosuperior axial projection with exaggerated external rotation

Quiz Me

• The body rotation for a posterior oblique position (Grashey method) is D. 35° to 45°

Quiz Me

• The most distal humeral structure is D. Surgical neck

Quiz Me 2

• The mid area of the costal surface of the scapula is the A. Subscapular fossa

Clavicle & AC Joints

• Chapter 5 Continued

Learning Objectives

• Identify the following joints on an image of the upper extremity:
  • AC - Acromioclavicular Joint
  • SC - Sternoclavicular Joint
• Describe the anatomy and positioning of the shoulder girdle and upper extremity
• Identify the following parts and prominences on an image or skeleton:
  • Clavicle
    • Body
    • Sternal end
    • Acromial end

Test your knowledge of the proximal humerus anatomy, including its structure and associated joints. This quiz covers important features such as the head, neck, tubercles, and major muscle attachments. Evaluate your understanding of this essential component of the upper extremity.