PERIPHERAL NERVOUS SYSTEM Flashcards
LOWER MOTOR NEURON LESION - DEFINITION
Lower motor neuron lesions are lesions anywhere from the anterior horn of the spinal cord, peripheral nerve, neuromuscular junction, or muscle. This type of lesion causes hyporeflexia, flaccid paralysis, and atrophy.
LOWER MOTOR NEURON LESION - CAUSE
Most common cause is trauma to peripheral nerves that serve the axons, and viruses that selectively attack ventral horn cells
LOWER MOTOR NEURON LESION - SIGNS AND SYMPTOMS
- Weakness - limited to focal or root innervated pattern
- Muscle atrophy (wasting) - prominent in a focal pattern
- Reflexes - absent or reduced in a lower motor neuron lesion
- Fasciculation’s present in the associated muscle group - Fasciculations = muscle twitching
- Babinski sign absent - downward going digits
- hypotonia or atonia - tone is not velocity dependent
RADIAL NERVE IMPINGEMENT - DEFINITION
- Impingement of the radial nerve
- The nerve travels from the armpit down the back of the arm to the hand
- It helps to move the arm, wrist and hand
RADIAL NERVE IMPINGEMENT - CAUSES
- Broken arm bone and other injury
- Diabetes
- Improper use of crutches leading to excess pressure in the armpit
- Lead poisoning
- Long-term or repeated constriction of the wrist
- Long term pressure on the nerve, usually causes by swelling or injury of nearby body structures
- Pressure to the upper arm from arm positions during sleep or coma
RADIAL NERVE IMPINGEMENT - SIGNS AND SYMPTOMS
- Abnormal sensations in the back and thumb side of the hand, or in the thumb, 2nd and 3rd fingers
- Weakness of fingers
- Loss of coordination of fingers
- Problem straightening the arm at the elbow
- Problem bending the hand back at the wrist or holding the hand
- Problems in the areas controlled by the nerve
o Px
o Numbness
o Decreased sensation
o Tingling
o Burning sensation
RADIAL NERVE IMPINGEMENT - PROGNOSIS
- In most cases the impingement can be treated successfully with a good chance of full recovery
- Sometimes no treatment is needed
- Medications can be used if needed
o Over the counter prescription px medications
o Corticosteroid injections around the nerve to reduce swelling and pressure - Supportive splint
- Elbow pad
- Physical therapy to maintain the muscle strength in the arm
MEDIAN NERVE IMPINGEMENT - DEFINITION
- Impingement of the median nerve
- Mononeuropathy that affects movement of or sensation in the hand
MEDIAN NERVE IMPINGEMENT - CAUSE
- Caused by compression of the median nerve in the elbow or distally in the forearm or wrist with symptoms in the median nerve distribution only
- Injury
- Rheumatoid or wrist arthritis
- Stress from repetitive work
- Hobbies or sports activities
- Obesity
MEDIAN NERVE IMPINGEMENT - RISK FACTORS
- Sex - Women more likely
- Bone spurs - Trauma or a condition that causes bone thickening, such as OA
- Rheumatoid arthritis
- Thyroid disease
- Diabetes
- Overuse
- Obesity
- Pregnancy
- Prolonged bed rest
MEDIAN NERVE IMPINGEMENT - SIGNS AND SYMPTOMS
- Hand or wrist px, numbness, weakness or tingling
- Hand px that wakes you up at night
- Px, burning or tingling sensation in the forearm
- Problems grasping items, writing or using a keyboard
- Tenderness or px in the elbow
- Loss of muscle in the thumb (rare symptom)
MEDIAN NERVE IMPINGEMENT - PROGNOSIS
- Prognosis depends on the severity of the injury
- Prognosis for median nerve impingement is usually good
ULNAR NERVE IMPINGEMENT - DEFINITION
Ulnar nerve entrapment affects your ulnar nerve in your arm
ULNAR NERVE IMPINGEMENT - CAUSE
- Can occur when there is prolonged stretching of the nerve by keeping the elbow fully bent or when there is direct pressure on the nerve from leaning the elbow against a solid surface
- Entrapment at the wrist can occur when there is direct pressure on the berve by leaning on handlebars during long bike rides or prolonged use of hand tools
- Accidents
- Arthritis
- Broken bones or bone spurs
- Diabetes
- Dislocated elbow
- Tumours or cysts
ULNAR NERVE IMPINGEMENT - RISK FACTORS
- Sex - Men more than women
- Sports
o Baseball players
o Golfers
o Tennis players
o Bicyclists - Construction workers
- People who smoke
- Typists, writers and others who use a keyboard frequently
- Weightlifters
ULNAR NERVE IMPINGEMENT - SIGNS AND SYMPTOMS
- Px in forearm
- Tingling in forearm
- Numbness in forearm
- Weakness in the hand
- Tenderness in the hand
- Tingling in the palm and 4th and 5th fingers
- Sensitivity to cold
- Tenderness in the elbow joint
- Loss of muscle mass (in severe cases)
ULNAR NERVE IMPINGEMENT - PROGNOSIS
- Usually not serious
- But can have permeant consequences without prompt treatment
o Paralysis and loss of feeling in the affected hand or arm - With proper diagnosis and treatment most people with ulnar nerve impingement can make a full recovery
MUSCULOCUTANEOUS NERVE IMPINGEMENT - CAUSES
MUSCULOCUTANEOUS NERVE IMPINGEMENT - SIGNS AND SYMPTOMS
- Weakness in elbow or shoulder flexion
- Atrophy of biceps brachii
- P or paraesthesia at lateral forearm
MUSCULOCUTANEOUS NERVE IMPINGEMENT - PROGNOSIS
- Several months typically required after axonotmesis injury
- 2-9 months
AXILLARY NERVE IMPINGEMENT - CAUSE
- Systemic disorder that causes nerve inflammation
- Fracture of humerus
- Pressure from cast or splint
- Shoulder dislocation
AXILLARY NERVE IMPINGEMENT - SIGNS AND SYMPTOMS
- Shoulder or arm muscle weakness
- Shoulder or arm wasting
- Numbness in arm- around deltoid
AXILLARY NERVE IMPINGEMENT - PROGNOSIS
- Full recovery usually occurs
- 6-12 months
FEMORAL NERVE IMPINGEMENT - CAUSE
- Direct trauma
- Prolonged pressure on nerve
- Compression, stretching or entrapment of nerve- e.g., by tumour or abnormal blood vessel
FEMORAL NERVE IMPINGEMENT - SIGNS AND SYMPTOMS
- Leg, ankle or foot numbness/tingling/weakness
- Lower back P
- Difficulty straightening knee, leg or ankle
- Muscle atrophy in legs
- Impaired gait
FEMORAL NERVE IMPINGEMENT - PROGNOSIS
- If left untreated, can lead to permanent damage or death of nerve
OBTURATOR NERVE IMPINGEMENT - CAUSES
- Compression during pregnancy
- Can become entrapped at exit of obturator canal or more distally by fascia
- Trauma
- Nerve being stretch during surgery
OBTURATOR NERVE IMPINGEMENT - SIGNS AND SYMPTOMS
- Medial thigh or groin P
- Weakness with leg adduction
- Sensory loss in medial thigh of affected side
OBTURATOR NERVE IMPINGEMENT - PROGNOSIS
- Without treatment, entrapment of obturator nerve can lead to ongoing P in groin
SCIATIC NERVE IMPINGEMENT - CAUSES
- Herniated disc
- Bony spur
SCIATIC NERVE IMPINGEMENT - SIGNS AND SYMPTOMS
- Painful- P may be stabbing, burning, stabbing
- Tingling- like pins and needles
- Numb down back of leg
- Weak hamstrings etc
SCIATIC NERVE IMPINGEMENT - PROGNOSIS
- Usually goes away on its own with time and self-care treatments
- Ice, stretching, NSAIDs
