Brachial Plexus Anatomy (OT 505) PDF

Peripheral Nervous System: Brachial Plexus OT 505 Review: ! What is the peripheral nervous system? ! Nervous tissue outside the vertebrae canal and brainstem ! Connects the body to the central nervous system ! What is the peripheral nervous system comprised of? ! Cranial Nerves ! Spina...

Peripheral Nervous System: Brachial Plexus OT 505 Review: ! What is the peripheral nervous system? ! Nervous tissue outside the vertebrae canal and brainstem ! Connects the body to the central nervous system ! What is the peripheral nervous system comprised of? ! Cranial Nerves ! Spinal Nerves ! 8 Cervical ! 12 Thoracic ! 5 Lumbar ! 5 Sacral ! 1 Coccygeal Plexus Formation (except for thoracic nerves) ! Anterior rami of the spinal nerves will join together and or branch out forming a network known as a PLEXUS ! 3 Major Plexuses ! CERVICAL PLEXUS C1-C4-muscles of neck ! BRACHIAL PLEXUS C5-T1-muscles upper limb ! LUMBOSACRAL PLEXUS L1-S5- muscle lower limb ! THORACIC NERVES INTERCOASTAL NERVES PLEXUS FORMATION  ! Anterior rami of the the first 4 cervical nerves C1-C4- form the cervical plexus ! Branch C2- Sternocleidomastoid CERVICAL ! Branch C3 and C4 Trapezius PLEXUS ! Branch C3 –C5 Levator Scapula ! Branch C4 Anterior Scalene ! Branches C3-C4 Middle Scalene ! Branches C3-C5 PHRENIC NERVE--DIAPHRAGM Brachial Plexus ! Anterior rami C5-T1 spinal nerves ! Formed from the junctions of the ventral rami of the cervical roots ! Splits and joins several times before ending Brachial Plexus ! Spinal nerves exit to form: ! 5 Roots ! 3 Trunks ! Superior C5-6 ! Middle C7 ! Inferior C8-T1 ! 6 Divisions ! Anterior, Posterior ! 3 Cords ! Lateral ! Posterior ! Medial ! 5 Branches ! Musculocutaneous ! Axillary ! Radial ! Median ! Ulnar mnemonic device=read the darn cadaver book  Brachial Plexus Path Scalene Muscle Anterior Medial Posterior The Brachial Plexus, with the subclavian artery and vein runs between the anterior scalene & the middle scalene ROOTS ! C5-6 ! C7 ! C8-T1 Roots ! Two nerves arise from the roots directly: ! Dorsal Scapular nerve (C5) ! Rhomboids ! Levator Scapulae ! Long thoracic nerve (C5, C6, C7) ! Serratus Anterior  TRUNKS Form from the roots Superior (Upper) Trunk C5- C6 Middle Trunk C7 Inferior (Lower) Trunk C8-T1 Nerves that arise from the trunks (Superior trunk C5- C6) Suprascapular Nerve Supraspinatus Infraspinatus Subclavius Nerve Subclavius  Path of Brachial Plexus CLAVICLE- Trunks Just distal to clavicle, each trunk divides (divisions) into anterior and posterior division Supraclavicular- in the posterior triangle of the neck are the roots Infraclavicular- in the 1stRib- C8, T1 unite at axilla neck of the first rib to form lower trunk  Divisions Posterior to the mid clavicle, the trunks divide to form the anterior(lateral and medial) and posterior divisions LATERAL AND MEDIAL- supply muscles of the anterior compartments (flexors) POSTERIOR- supply muscles of the posterior compartments (extensors) NO nerves off of the divisions  CORDS The divisions turn into cords Named in reference to their position to the axillary artery CORDS Lateral Medial Posterior  Lateral Cord Nerves off lateral cord ▪ Lateral Pectoral nerve ▪ Pectoralis Major Medial Cord Nerves off medial cord: ▪ Medial pectoral nerve ▪ Pectoralis Major ▪ Pectoralis Minor  Posterior Cord Nerves off posterior cord ▪ Upper subscapular nerve ▪ Subscapularis ▪ Thoracodorsal nerve ▪ Latissimus Dorsi ▪ Lower subscapular nerve ▪ Subscapularis ▪ Teres Major  BRANCHES Terminal branches come off the cords Musculocutaneous Axillary Median Radial Ulnar AXILLARY NERVE !Innervations: !Deltoid !Teres Minor !Long Head of Triceps MUSCULOCUTANEOUS NERVE !Innervations: ! Biceps Brachii ! Brachialis ! Coracobrachialis RADIAL NERVE !Innervations: ! Triceps ! Anconeus ! Brachioradialis ! Supinator ! 10 other muscles, 8 form a branch from the radial nerve called the PIN MEDIAN NERVE !Innervations: !Pronator Teres !Pronator Quadratus (AIN- Branch of Median Nerve) !9 other muscles that are innervated by either median or AIN ULNAR NERVE ! Innervates 11 muscles Innervates: 11 muscles OVERVIEW  Common Pathologies of Peripheral Nerves !Neuropathy: Neurological deficit along the nerve pathway Brachial Plexus: !TOS- compromised nerves between the clavicle/first rib !Burner/Stinger Syndrome- stretch after blow to head/ shoulder (football, gymnasts , wrestlers) immediate burning/ paralysis radiating from neck  Pathologies of Brachial Plexus Scapular Winging: Long Thoracic near weakens/paralyzes Serratus Anterior Erbs Palsy ! Upper Trunk injury-C5-C6 (occasionally includes C7) ! “waiter’s tip” position of arm ! Nerves: Musculocutaneous Axillary Dorsal Scapular Suprascapular Klumpke’s palsy ! Lower Trunk Injury (C8, T1) ! Nerves: Ulnar Nerve Medial Pectoral Nerve Thoracodorsal nerve