Superficial Back Learning Objectives

Distinguish between the extrinsic and intrinsic back muscles

Extrinsic muscles are divided into 2 layers (superficial and intermediate), their function is limb movement and respiration/proprioception respectively

Intrinsic muscles are in the deep layers and their function is vertebral column movement/stabilization

Superficial Extrinsic Muscles

Trapezius, Latissimus Dorsi, Rhomboids, Levator Scapulae

Intermediate Extrinsic Muscles

Serratus Anterior Superior, Serratus Anterior Inferior

Intrinsic Back Muscles

3 layers deep to the extrinsic back muscles

Superficial Layer of Intrinsic Back Muscles

Splenius Muscles (capitis and cervicis)

Intermediate Layer of Intrinsic Back Muscles

Erector Spinae group (from medial to lateral: Spinalis, Longissimus, Iliocostalis)

Deep Layer of Intrinsic Back Muscles

Transversospinalis group (Semispinalis, Multifidus, Rotatores)

Identify the following surface anatomical structure: External Occipital Protuberance

Base of the skull

Identify the following surface anatomical structure: Spinous Process of Seventh Cervical Vertebrae (Vertebra Prominens)

Most prominent spinous process at the base of the neck

Identify the following surface anatomical structure: Spine of the scapula

Medial to acromion process

Identify the following surface anatomical structure: Acromion of the scapula

End of spine of scapula laterally

Identify the following surface anatomical structure: Medial (vertebral) border of scapula

Medial side of scapula spanning from superior angle to inferior angle

Identify the following surface anatomical structure: Inferior Angle of Scapula

Most inferior part of medial border of scapula

Identify the following surface anatomical structure: Spinous Processes of Thoracic Vertebrae

Spinous processes inferior to vertebra prominens

Identify the following surface anatomical structure: Iliac Crest

Easy to identify at lateral portion of pelvis

Identify the following surface anatomical structure: Posterior Superior Iliac Spine

Palpate around the dimples of the lower back