Lecture Notes - Superficial Back

Anatomical position and nomenclature

• Planes - sagittal, coronal, transverse, or oblique
• Relative positions
  • superficial - deep
  • medial - lateral
  • anterior (ventral) - posterior (dorsal)
  • superior (cranial) - inferior (caudal)
  • proximal - distal (used in limbs only)

General Organization of the Body - Arm as an example

• Skin
  • Structure
    • epidermis
    • dermis - the "leather" portion; mostly connective tissue with hair follicles (with arrector pili muscles), sweat and sebaceous glands, blood and lymph vessels, and nerves; fiber orientation controls cleavage lines in skin and affects stretch marks, wrinkles and scar formation
  • Accessory structures and appendages - teeth (enamel), hair, nails, glands (sweat, sebaceous, mammary)
  • Functions
    • epidermis - serves as water barrier (keratin), protects underlying tissues and organs from physical injury and from solar radiation, maintains body temperature, is major sense organ, excretes, absorbs and synthesizes vitamin D
    • dermis - provides for physical integrity and flexibility of skin
  • Injuries to skin
    • abrasions
    • lacerations
    • contusions (bruises)
    • burns, Ist degree (red), 2nd degree (blister), and 3rd degree (skin destroyed)
• Fascia
  • subcutaneous tissue or superficial fascia (a.k.a. fat or panniculus adiposis) - allows movement of skin on deeper structures
  • investing or deep fascia - encloses regions, muscles, forms compartments - named specializations
• Muscle and muscular fascia
• Loose connective tissue between muscles and organs
  • allows movement of parts
  • contains neurovascular elements
  • can be site of fat storage
• Neurovascular bundles
  • arteries
  • veins
  • lymphatics
  • nerves
• Bone or body cavity - form deepest structures, cavities are lined by internal fascia and lining membrane

Pectoral girdle

• components
  • scapula
  • clavicle
• attachments
  • sternoclavicular joint
  • superficial back and pectoral muscles

Superficial back muscles

• trapezius
• latissimus dorsi
• levator scapulae
• rhomboideus major
• rhomboideus minor
• triangles:
  • ausculation
  • lumbar

Nerves

• spinal accessory n. (Cranial Nerve XI) - motor to trapezius
• C3, C4 (sensory from trapezius) and subtrapezial plexus
• dorsal scapular n (C5)
• thoracodorsal n (C5, 6) (not seen yet)
• cutaneous nn. of back
  • distinction between cutaneous vs sensory nerves, muscular vs motor nerves
  • origin - dorsal primary rami (DPR) of spinal nerves
  • distribution
  • greater occipital n. - from DPR of C2

Vessels

• transverse cervical artery and vein
• dorsal scapular artery and vein
• segmental arteries and veins
• thoracodorsal artery and veins (not seen yet)