Superficial Back Flashcards
(34 cards)
Surface landmarks of superficial back
- External occipital protuberance
- Vertebral prominens (C7)
- Fold of trapezius
- Spine of scapula
- Medial border of scapula
- Intrinsic back muscles
- L4 vertebra
- iliac crest
- posterior superior iliac spines
Superficial back attachment points on skull
Mastoid process of temporal bone; External occipital protuberance, superior and inferior nuchal lines of occipital bone
Vertebral column
33 vertebrae; functions:
- support body weight
-posture
-locomotion
-protection of spinal cord/roots
Typical vertebrae
Body, vertebral arch (formed by laminae and pedicles), 7 processes (1 spinous, 2 stransvers, 4 articular)
Clavicle Osteology
-Sternoclavicular joint at medial/sternal end
-Acromioclavicular joint and attachment of trapezius at lateral/acromial end
-Conoid tubercle - attachement of coracoclavicular lig.
-Groove for subclavius
Scapula Osteology
Attachments for axioappendicular muscles
humerus
-greater tubercle (posterior)
-lesser tubercle (anterior)
-Intertubercular groove (anterior) lat attachment site
Dorsal vertebral ligaments
interspinous ligaments
supraspinous ligament
ligamentum flavum
Ligamentum nuchae
posture and trap stability during contraction. Attaches at ext. occipital protuberance and spinous process of C7
Thoracolumbar fascia
separates deep and superficial back muscle
Intrinsic back muscles
deep muscles; posture and movements
Extrinsic back muscles
superficial back muscles; attach pectoral girdle to axial skeleton
movement of scapula or humerus
Innervation of superficial back
determined in early development; muscles innervated by spinal nerves from SC near site of development
Trapezius and SCM
cervical somites, innervated by CNXI, motor fibers from C1-5,6
Latissimus Dorsi
formed from myoblasts in somites in lower cervical/upper thoracic migrating to site of upper limb formation
innervated by Thoracodorsal nerve (C5,6,7) from brachial plexus
Dorsal rami
innervate intrinsic back muscles and suboccipital muscles
Ventral rami
innervates virtually everything else
1st layer of superficial back muscles
trap and lat
2nd layer of extrinsic back muscles
levator scapular, rhomboid minor and major
3rd layer of intermediate muscles
serratus posterior superior and inferior
Trapezius
Origin - occipital protub, nuchal ligament, spinous process
insertion - spine + acromion of scapula, lateral 1/3 clavicle
Innervation by CNXI
Mulitple movements : scapula elevation (descending), retraction (middle), depression (ascending), upward rotation (descending +a ascending)
Spinal Accessory Nerve
C1-C5, 6 ventral rami exiting skull via jugular foramen. Damage to this nerve can cause shoulder drop and weakness, difficulty lifting upper limp > 90 degrees
Latissimus dorsi
Origin - T7 to T12 spinous process
Insertion - Inter-tubercular groove of humerus between pec and teres maj
Innervation - Thoracodorsal nerve of C6,7,8
Action - arm extension, medial rotation, adduction, and moves trunk forward when humerus fixed (crutches)
Levator scapulae
elevates scapula
internal rotation