Peripheral Nerve Injuries and Their Diagnosis

Study Notes

Types of Peripheral Nerve Injuries

Neuropraxia:
- Temporary impairment due to demyelination.
- Full recovery expected, often within weeks.
Axonotmesis:
- Damage to the axon with preservation of the surrounding connective tissue.
- Regeneration can occur, but may take months.
Neurotmesis:
- Complete transection of the nerve.
- Surgical intervention often required for recovery.

Diagnostic Methods

Physical Examination:
- Assessment of motor and sensory function.
- Reflex testing to evaluate nerve integrity.
Electromyography (EMG):
- Measures electrical activity of muscles.
- Determines nerve function and muscle response.
Nerve Conduction Studies (NCS):
- Assesses the speed and strength of electrical signals in nerves.
Ultrasound:
- Visualizes nerve structure and assesses for lesions or compressions.
MRI:
- Provides detailed images of soft tissues, including nerves.

Treatment Options

Non-surgical:
- Rest and observation for mild injuries.
- Medications: pain relief (NSAIDs, corticosteroids).
Surgical:
- Decompression: relieve pressure on the nerve.
- Repair or grafting: reconnecting or bridging the nerve ends.
Bracing and Splinting:
- Supports the affected limb to prevent further injury and promote healing.

Rehabilitation Techniques

Physical Therapy:
- Strengthening and range of motion exercises.
- Manual therapy techniques to improve function.
Occupational Therapy:
- Focuses on activities of daily living and adaptive techniques.
Sensory Re-education:
- Techniques to improve sensory perception and function.
Electrical Stimulation:
- Used to facilitate muscle contraction and alleviate pain.

Anatomy Of Upper Extremity Nerves

Brachial Plexus:
- Network of nerves originating from C5 to T1.
- Supplies upper limb motor and sensory innervation.
Major Nerves:
- Median Nerve: innervates flexors of the forearm, thenar muscles, and sensory to parts of the palm.
- Ulnar Nerve: innervates intrinsic hand muscles and provides sensory to the ring and little fingers.
- Radial Nerve: controls extension of the arm and provides sensory to the posterior arm and forearm.
Common Sites of Injury:
- Wrist (Median nerve at carpal tunnel).
- Elbow (Ulnar nerve at cubital tunnel).
- Upper arm (Radial nerve due to Saturday night palsy).

Types of Peripheral Nerve Injuries

Neuropraxia is a temporary impairment due to demyelination, with full recovery expected within weeks
Axonotmesis involves axon damage but preserves surrounding connective tissue, resulting in regeneration that can take months
Neurotmesis is a complete nerve transection requiring surgical intervention for recovery

Diagnostic Methods

Physical examinations assess motor and sensory function, including reflex testing to evaluate nerve integrity
Electromyography (EMG) measures muscle electrical activity to determine nerve function and muscle response
Nerve conduction studies (NCS) assess the speed and strength of electrical signals in nerves
Ultrasound visualizes nerve structure and identifies lesions or compressions
MRI provides detailed images of soft tissues, including nerves

Treatment Options

Non-surgical options include rest, observation for mild injuries, and pain relief medications like NSAIDs and corticosteroids
Surgical treatments include decompression to relieve nerve pressure, and repair or grafting to reconnect or bridge nerves
Bracing and splinting support the affected limb to prevent further injury and facilitate healing

Rehabilitation Techniques

Physical therapy focuses on strengthening, improving range of motion, and manual therapy techniques
Occupational therapy addresses activities of daily living and adaptive techniques
Sensory re-education improves sensory perception and function
Electrical stimulation facilitates muscle contraction and reduces pain

Anatomy Of Upper Extremity Nerves

The brachial plexus is a network of nerves originating from C5 to T1, supplying motor and sensory innervation to the upper limb
Median nerve controls forearm flexors, thenar muscles, and provides sensory innervation to parts of the palm
Ulnar nerve innervates intrinsic hand muscles and provides sensory innervation to the ring and little fingers
Radial nerve controls arm extension and provides sensory innervation to the posterior arm and forearm
Common injury sites include the wrist (Median nerve at carpal tunnel), elbow (Ulnar nerve at cubital tunnel), and upper arm (Radial nerve due to Saturday night palsy)

Description

This quiz covers the types of peripheral nerve injuries including neuropraxia, axonotmesis, and neurotmesis. It also highlights diagnostic methods such as electromyography and nerve conduction studies. Test your understanding of nerve injuries and their treatment options.