Objectives. Principles of Neurodynamics. Objectives. Foundations of Anatomy. Peripheral Nervous System (PNS) Structure Meets Function

Transcription

1 Principles of Neurodynamics Jason Zafereo, PT, OCS, FAAOMPT With contributions from: Leslie Nelson, PT Objectives Participant will review the relevant anatomy and function of the peripheral, central, and autonomic nervous systems Participant will describe the intraneural and extraneural factors contributing to nerve injury Objectives Participant will describe the tension points in the body where pathology is most likely to occur Participant will review a system of examination for adverse neural tension Foundations of Anatomy Continuous tissue tract Connective tissue interconnected Electrically interconnected neurons Chemical consistency Neurotransmitters Cytoplasm Structure Meets Function Peripheral Nervous System (PNS) Accommodation of body movements Meninges (Endo, peri, epi)-neurium Impulse conduction Axons Myelin Axon Run undulatory course in endoneurial tubes Myelin

2 Peripheral Nervous System Diagram of Connective tissue coverings Central Nervous System Nerve roots Undulations Dural and epidural meninges Extrathecal attachments (low cervical, LS) Plugging by dorsal root ganglion Central Nervous System Spinal cord Undulations Movement in relation to neighboring vertebral segments Meninges Pia and arachnoid mater Dura mater Autonomic Nervous System Sympathetic trunk and ganglia Pre-ganglionic neurons Head and neck C8-T5 UE T2-T10 LE T10-L2 Post-ganglionic neurons Efferent to smooth muscle and glands Intraneural Causes of ANT Vascular considerations Decreased blood supply to nervous system Disruptions in axonal transport Nociceptive stimulation of connective tissue coverings of nervous system 2% of body mass consumes 20% of available Oxygen CNS: Critical vascular zone exists from T4-T9 Narrow spinal canal PNS: Arrest of blood flow at 8% elongation, complete at 15%

3 Axonal transport systems Two-way movement of materials and substances in the cytoplasm Double crush Innervation of Connective Tissue Meninges Dura mater highly innervated ventrally Arachnoid/pia mater innervation uncertain (Endo, peri, epi)-neurium Intrinsic innervation Free nerve endings Extraneural Causes of ANT Intraneural versus Extraneural Symptom & Sign Differentiation Mechanical Interface Spinal foramen Muscle/fascia Joint Ligament Blood vessel Description of symptoms Physical signs Extraneural Catches, twinges around vulnerable areas Comparable signs with movement of interfacing structure Intraneural (Conducting) Burning, tingling, electric in innervation field Neurological signs and symptoms; palpation refers sx elsewhere; increased sx with tension testing Intraneural (Connective) Lines of pain, along trunks, nondermatomal Palpation elicits local pain; increased sx with tension testing Sites of Injury Tunnels Soft tissue, osseus or fibro-osseus tunnels Where the nervous system branches Where the system is relatively fixed Where the nerves pass over unyielding interfaces Tension points Median nerve in carpal tunnel Spinal nerve in intervertebral foramen Posterior interosseus nerve in arcade of Frohse

4 Branches Union of lateral and medial plantar nerves to form the common plantar digital nerve Fixed System Common peroneal nerve at head of fibula Dura mater at L4 Radial nerve to the head of radius Suprascapular nerve in scapular notch Unyielding Surface Cords of plexus over first rib Radial nerve in radial groove of humerus Dural sleeve at pedicles Unyielding Surfaces (continued) Greater occipital nerve through fascia Lateral femoral cutaneous nerve through fascia Nerves in feet through plantar fascia Tension Points Key points in the body where movement demands (and tension) are increased C6 T6 L4 Tibial nerve at posterior knee Median nerve at anterior elbow Neurodynamic Examination Tension testing Longitudinal deformation Elasticity intraneural Elasticity extraneural Palpation Perpendicular deformation Neurological testing

5 Tension Testing Palpation ULTT1 SLR Palpate nerves under tension Final thoughts The interconnectedness of the nervous system must be considered when evaluating and treating patients with adverse neural tension. These patients are often misdiagnosed, so check for adverse neural tension when treatment is not progressing as planned. Thank You