HC1 Second half

• Disc degeneration


  Makes the disc stiffer and the annulus weaker and increases risk of tears
• Nucleus pulposus


  Dehydrates and changes from jelly to fibrocartilaginous structure, disc thinner and shorter
• Intervertebral foramen


  Size is reduced from compression on facet joints and causes nerve root impingement
• Radiculopathy


  Nerve root impairment due to compression or ischemia, radiating pain numbness and tingling, blocked sensory nerves and muscle weakness from obstructed motor nerves
• Radicular Pain and Radiculitis


  Pain radiating directly along course of a spinal nerve root, can start at injury site and radiate outwardly to extremities
• Intervertebral Disc Disease


  Stress exceeds the mechanical capabilities of a disc or when disc degenerates, lesions or herniations occur, vertebral endplate develops fractures under excessive loading in compression
• Disc Herniation


  • Degeneration
  • Prolapse
  • Extrusion
  • Sequestration
• Degenerative Disc Disease


  Difficult to distinguish from normal age-related changes, disc will start early degeneration and progress over time
• Sciatica


  Pressure and irritation of the sciatic nerve, travels from the back of the leg
• Spinal Stenosis


  • Congenital: idiopathic or developmental narrowing
  • Acquired: degeneration of bone or ligaments and IVD protrusion
• Lumbar spinal stenosis


  Disabling and progressive low back pain, leg weakness, forward stooped posture
• Spondylosis


  Degenerative changes due to OA, osteophytes come away from body of vertebrae and cause pain if nerve root is exposed or has been compressed
• Spondylolysis


  Bilateral defect in the pars interarticularis of a vertebra that decreases ability of posterior elements to stabilize movement
• Spondylolisthesis


  Vertebra translates forward in sagittal plane with respect to vertebra below
• Tests


  • Passive physiological intervertebral mobility
  • MMT
  • Mechanical provocation tests
• Neurodynamic Tests


  • SLR: lumbrosacral nerve roots and sciatic nerve
  • Prone knee bent test: stressed femoral nerve and L2/L3 nerve roots
  • Slump test: extreme SLR with ankle DF, sitting with thoracolumbar flexion
• Peripheral Nervous System


  Includes motor, sympathetic and parasympathetic neurons
• Efferent (motor) pathways


  • Somatic motor nerves innervate skeletal muscles
  • Parasympathetic - smooth muscle, cardiac and glandular activity
  • Sympathetic - fight or flight
• Afferent (sensory) pathways


  Send messages from periphery to centre, transmit sensations
• Mechanisms of nerve injury

  • Excessive compression of a nerve
  • Nerve laceration
  • Ischemia
  • Exposure to excessive electricity, heat, radiation or toxins
  • Single application of high force traction
  • Repeated application of lower levels of traction
  • Accidental injection
• Levels of nerve injury

  • Neurapraxia
  • Axonotmesis
  • Neurotmesis
• Neurapraxia


  Contusion or bruise of a nerve with full spontaneous recovery in days to weeks
• Axonotmesis


  Nerve fibers distal to site of injury degenerate but internal organization remains intact
• Neurotmesis


  Complete laceration of nerve
• Criteria for functional recovery from peripheral nerve injury

  • Survival of the cell body
  • Absence of barriers, such as scar or bone that would prevent axonal sprouting
  • Accurate growth toward appropriate end organ
  • Accommodation of CNS to reorganize afferent signals
• Wallerian degeneration


  Degeneration that occurs when a fiber is cut or crushed causing distal nerve segment degeneration
• Rates of nerve regeneration


  • Upper arm: 2-8mm each day
  • Proximal forearm: 2-6mm/day
  • Wrist: 1-2mm/day
  • Hand: 1-1.5mm/day
  • Upper leg: 2mm/day
  • Lower leg: 1.5mm/day
  • Ankle: 1mm/day
• Radial nerve damage


  Extensor and supinators leading to wrist drop
• Median nerve damage


  Forearm flexors leads to ape hand
• Ulnar nerve damage


  Leads to claw hand
• Repetitive strain injury


  Result of body's response to repetitive stress with the stress being the trauma
• Types of repetitive strain injury

  • Type 1: diagnose from symptoms- pain and inflammation
  • Type 2: not diagnosed because the only symptom is pain
• Etiology of repetitive strain injury

  Local muscle and overall fatigue, limited rest opportunities, jobs that involve awkward postures, repetition of movement, in cold settings, high force movements
• Symptoms of repetitive strain injury

  • Pain, tenderness, stiffness, throbbing, numbing, tingling, weakness, cramping
• Tests for repetitive strain injury

  • Provocative tests (Tinels, Phalens)
  • Reflex integrity
• Conditions related to repetitive strain injury

  • Tendonitis: tennis elbow, de Quervains disease
  • Nerve compression or entrapment: carpal tunnel
  • Myofascial pain: trigger points
• Carpal Tunnel


  Compression on median nerve, inflammation from repetitive movements, tunnel size narrows causing compression, common in pregnancy, more common in women, worse at night
• DeQuervainsor Mommy's Thumb


  Chronic repetitive overuse of wrist, such as grasping pinching and wringing movements, affects tendons on thumb (radial) side, affects extensor pollicis brevis and abductor pollicis longus, women more likely to get
• Tennis elbow


  Aka lateral epicondylitis, overuse of extensor carpi radialis, pain or burning when holding object, pain radiate down wrist and forearm, weak grip strength
• Golfers elbow


  Overuse of pronators and flexors at wrist, worsened with forearm activity like swinging a golf club or throwing a ball, pain or burning in the inner elbow radiating down wrist, weak grip strength