Exam 3: Thoracic Nerves Flashcards
___ pairs of thoracic spinal nerves
12
Each mixed nerve divides into
Posterior and anterior primary ramus
Posterior primary ramus projects posteriorward and divides into
Medial and lateral branch
Medial and lateral branches of posterior primary rami are
Mixed
Medial branches have ____ function
Motor and sensory
Muscles supplies by medial branch of posterior primary rami
Semispinalis (upper 6)
Longissimus (lower 6)
Multifidi (all)
Medial branches of posterior primary rami sensory supply
Skin paraspinally
Lateral branches _____ from superior to inferior
Increase in size
Muscles supplied by lateral branches of posterior primary rami
Longissimus
Iliocostalis
Levator costarum
Lateral branches of posterior primary rami sensory supply
Skin near costal angles
Anterior primary generally follow course of
Rib above the nerve
Anterior primary of T2 (sometimes T1) contribute to
Intercostobrachail N
Anterior primary ramus of T1 will contribute to
Brachial plexus
A smaller branch of T1 will form
1st intercostal N
Each intercostal N gives off a
Lateral cutaneous branch
Lateral cutaneous brancches divide into
Anterior and posterior branches
Lateral cutaneous branches sensory supply
Overlying skin
Intercostal nerves terminate as ___ which supply
Anterior cutaneous branches
Skin close to midline
Muscles supplied by intercostal N
Internal/external intercostals Innermost intercostals Serratus poterior Transversus thoracis Transverse abdominal Internal/external oblique Rectus abdominis
Intercostal N also supply adjacent
BV
Bones
Joints
Ligs
Subcostal N is the ____ of thoracic nerves
Largest
Intercostal also contributes to
Lumbar plexus
Subcostal N may supply skin as far inferior as
Superior buttocks
Each T nerve communicates w/ sympathetic trunk by
Gray and white rami communicans
