PNS: Radial and Ulnar Nerve Lesions

PNS: Ulnar and Radial Nerve Lesions

• Understand nerve pathways.
• Identify compression sites.
• Treatment plans should be developed and implemented.

Class Outline

• The class will include a question period.
• Radial and ulnar sensory areas are identified.
• A lecture is scheduled.
• The class will assess treatment and homecare.

Radial Nerve

• Arises from the posterior cord of the brachial plexus (C5-T1).
• Passes through triangular interval/triceps hiatus.
• Courses along the spiral groove of the humerus, following the triceps medial head to the posterior axilla.
• Located anteriorly between the brachialis and brachioradialis muscles.
• Courses beneath the ECRL & ECRB.
• Runs lateral to the olecranon process when crossing the elbow.
• Divides into a posterior motor branch and a superficial sensory branch.

Radial Nerve Motor Function

• Controls the Triceps.
• Controls the Anconeus.
• Controls the Brachioradialis.
• Controls the ECRL & ECRB.
• Controls the Extensor Digitorum.
• Controls the Extensor Carpi Ulnaris.
• Controls the Extensor Digiti Minimi.
• Controls the Abductor Pollicis.
• Controls the Extensor Indicis.

Causes of Radial Nerve Lesions

• Fractures of the humerus, which is especially common at the spiral groove.
• Fractures of the radius can result in “radial nerve palsy,” especially in the proximal 1/3.
• Elbow dislocations.
• Compression at the Arcade of Frohse or Radial Tunnel.
• Prolonged pressure on the arm during surgery.
• Crutch Palsy/Saturday Night Palsy/Honeymoon Palsy can result in prolonged compression of the radial nerve at the axilla.
• Neuropraxia or axonotmesis.
• Possible Wallerian degeneration.

Radial Nerve Lesions S&S

• Altered sensation in the radial nerve distribution.
• Complete lesion results in wrist drop.
• Lesions proximal to the elbow affect both sensory and motor branches.
• Lesions distal to the elbow tend to affect either sensory OR motor function, but not both.
• Possible signs and symptoms include muscle wasting, swelling on the dorsum of the hand, pain, and asthesia in the webbing between digits 1 & 2.

Radial Nerve Palsy

• Commonly caused by a fracture of the humerus.
• Weakness or paralysis of wrist/finger extensors & forearm supinators (wrist drop).
• Possible weakness of triceps, with the specific symptoms depending on the injury location.
• Parasthesia in the dorsum of the hand, lateral 3.5 digits, and lateral forearm.

Saturday Night/Crutch/Honeymoon Palsy

• Prolonged compression at the posterior axilla or spiral groove.
• Intoxicated individuals pass out with their arm over a chair.
• Conditions occur when someone falls asleep with someone else on their arm.
• Incorrect use of crutches.
• Signs and symptoms include wrist drop, possible weakness to triceps, and parasthesia in the dorsum of the hand, lateral 3.5 digits, and lateral forearm.
• Can result in neuropraxia or axonotmesis.

Radial Tunnel Syndrome/Posterior Interosseus Nerve Syndrome

• Distal to the elbow, the radial nerve splits into a superficial radial nerve and the posterior interosseus nerve (PIN).
• Superficial radial nerve is a sensory nerve.
• Posterior interosseus nerve (PIN) is a motor nerve.
• PIN passes through the Arcade of Frohse in the Supinator, which can be a compression site.

Radial Tunnel Syndrome/Posterior Interosseus Nerve Syndrome

• After the Arcade of Frohse, the PIN travels through the Radial Tunnel.
• Travels through the Supinator, Brachioradialis, ECRL, and ECRB.
• Compression occurs from repetitive use of these muscles.

Radial Tunnel Syndrome/Posterior Interosseus Nerve Syndrome

• Pain is distal to the lateral condyle.
• Weakness/paralysis of wrist and finger extensors are present.
• Symptoms worsen with elbow extension and pronation.
• No sensory deficits.

Superficial Radial Nerve Syndrome/Wartenberg’s Syndrome/Cheiralgia Paraesthetica

• Compression of the sensory branch.
• Trauma is often a cause.
• May be caused by direct pressure on the nerve.
• Compression from watches.
• Compression from Handcuffs.
• Hypertoned or overused muscles such as the Brachioradialis and ECRL.
• Experience pain over the distal radial forearm.
• Paresthesia is felt in the dorsal hand.
• No motor deficits.

Radial Nerve Lesion DDx

• Differential diagnoses include radiculopathy.
• Brachial plexus injuries.
• Other sites of compression along the radial path.
• If pain is present include Lateral epicondylitis and DeQuarvain’s syndrome.

Assessments: History

• Assess the Location(s) of symptoms.
• Note the Onset.
• Establish the Nature of symptoms.
• Determine if the symptoms are Intermittent/chronic/episodic.
• Identify any Related patterns with work, sleep, hobbies, or exercise.
• Assess the Quality of symptoms, including Pain/NWT/coordination.
• Note any Skin changes.
• Note any Temperature changes.

Assessments: Obvs/Palp/Mvmt

• Perform a Postural Scan.
• Pay attention to to the waiter's tip alignment.
• Palpate for tenderness, HT muscles, and fascial restrictions.
• Check temperature changes and edema.
• Assess Shoulder/Elbow/Wrist ROM.
• Perform MMTs to check for muscle weakness or imbalances in wrist extensors, finger extensors, and ABD Policis.

Assessments: Special Tests

• Perform DTRs to test Triceps, brachioradialis.
• Sensory Testing on the Back of hand digits 1, 2, 3 and ½ of 4.
• Test the Web of the thumb.
• Perform ULTT 3 for radial nerve neurodynamic testing.
• Rule out conditions with TOS Tests, Finklesteins, and Lateral Epicondylitis tests.

Ulnar Nerve Pathway

• Originates from the medial cord of the brachial plexus (C8-T1).
• Runs from the axilla to the medial humerus.
• Located posterior to the medial epicondyle.
• Passes through the forearm between the FCU & FDP.
• Courses beneath the ECRL & ECRB.
• Crosses the flexor retinaculum between the pisiform and hook of hamate.
• Passes through Guyon’s Canal/unal tunnel.
• Ends in the palm to digits 1, 4, and 5.

Ulnar Nerve Motor Function

• Controls the Flexor Carpi Ulnaris.
• Controls the Flexor Digitorum Profundus.
• Controls the Abductor, flexor, opponens digiti minimi (hypothenar group).
• Controls the 3rd and 4th lumbricals.
• Controls the Palmar and dorsal interossei.
• Controls the Adductor pollicis.
• Controls the Flexor Pollicis brevis.

Ulnar Nerve Lesions: Claw Hand

• Characterized by Passive hand position.
• 5th MCP: extended and abducted.
• 5th IP: flexed.
• 4th MCP: extended.
• 4th IP: flexed.

Ulnar Nerve Lesions: Benediction Hand

• Passive hand position.
• Loss of lumbrical function.
• Digits 4 & 5 IPs & DIPs flex unopposed.

Ulnar Nerve Sensory Function

• Digits 5 and ½ of 4.
• Ulnar aspect of palm.

Ulnar Nerve Lesions: Complete Lesion

• Claw hand.
• Loss of thumb ADD.
• Muscle wasting in hypothenar and interosseous spaces.
• Anhydrosis and vasomotor changes.

Causes of Ulnar Nerve Lesions

• Fractures of the medial epicondyle, forearm, and wrist (Colles’).
• Elbow dislocation.
• Prolonged compression.
• Repetitive use.
• Trauma makes the nerve vulnerable at the elbow & wrist.

Tardy Ulnar Palsy

• Related to Post fracture.
• Sometimes develops years after initial fracture.
• Callus formation.
• Valgus deformity.
• Gradually stretches the nerve in the ulnar groove of the medial epicondyle.

Cubital Tunnel Syndrome

• Occurs with Passage between heads of FCU and FDP.
• The tunnel flattens on the ulnar nerve, which puts pressure on the nn.

Ulnar Tunnel/Guyon’s Tunnel Syndrome

• Formed by pisiform, hook of hamate, volar carpal ligament, and Transverse carpal ligaments.
• Contains the Ulnar nerve and Ulnar artery.

Ulnar Tunnel/Guyon’s Tunnel Syndrome

• Caused by pressure on the hypothenar eminence.
• Risks occur with Cycling, using jack hammers or other heavy tools, and general Keyboard usage.
• Trauma and swelling are causes.
• Carpal fracture and Arthritis are associated with this condition.

Ulnar Nerve Lesion DDx

• Consider radiculopathy.
• Consider brachial plexus injuries.
• Consider TOS.
• Evaluate Other compression sites along the nerve.
• Ulnar Nerve Lesion DDx may be present with pain.
• Triangular Fibrocartilage Complex (TFCC) Injuries.
• Ulnar collateral ligament (wrist) sprain.
• UCL (elbow) sprain.
• Elbow/wrist mm strains/tendinopathies.

Assessments: History

• Location(s) of symptoms should be assessed.
• Note the Onset of symptoms.
• Characterize the Nature of symptoms.
• Note if symptoms are Intermittent/chronic/episodic.
• Look for Related patterns.
• Determine if patterns occur during work, sleep, hobbies, or exercise.
• Evaluate the Quality of symptoms.
• Key indicators are Pain, Numbness, Weakness, and coordination.
• Note any Skin changes that may occur.
• Note any Temperature changes.

Assessments: Obvs/Palp/Mvmt

• Complete a Postural Scan.
• Scan for injuries such as claw hand.
• Palpate for tenderness, HT mm, and fascial restrictions.
• Determine temperature changes and edema/sweating levels.
• Assess Elbow/Wrist/Finger/Thumb ROM.
• Perform MMTs for muscle weakness or imbalances.
• Test strength in the FCU, FDP, Hypothenar group, Interossei, ADD P, and FPB.

Assessments: Special Tests

• Tinel’s Test should be performed on the ulnar nerve at the medial epicondyle.
• Determines amount of regeneration.
• Tapping the nn will elicit tingling.
• Froment’s Sign tests the Adductor Pollicis.
• Patient grasps paper between 1st and 2nd digit.
• Examiner tries to pull paper.
• A positive test occurs if patient flexes their IP to recruit flexors to maintain grasp because of weakness in ADDP.
• Sensory Testing assesses the Ulnar distribution
• ULTT 4 to test Ulnar nerve neurodynamic.

Treatment Goals: Regenerating nn

• Address areas proximal to the lesion or compensatory muscles:
  • Reduce fascial restrictions
  • Improve Manage edema
  • Reduce TrPs
  • Reduce HT mm
• Manage edema.
• Increase and maintain ROM & tissue health.
• Support motor and sensory function.
• Manage pain such as reducing FIDs.
• Promote relaxation.

Treatment: Regenerating nn

• Modalities include Segmental strokes proximal to lesion, perpendicular to the nerve.
• Use blocking/stabilization proximal to the nerve to prevent tissue drag.
• Address Flaccid tissue with light stroking, compressions, and directional treatment.
• Focus treatment of unaffected tissue toward, but not on, flaccid tissue
• PROM is used for movements that slacken and will not bias the affected nn.
• Stretching such as passive/PNF/pin and stretch may be used.
• Consider Positioning with the use of neutral pillows.
• Do not traction a regenerating nn.
• Do not stretch deservated tissue/muscles.

Homecare - Regenerating nn

• Splinting/bracing.
• Protect areas of decreased sensitivity with gloves.
• Implement Sensory Re-education.
  • This includes using Multiple kinds of stimulus texture and identifying Vibrations.
  • Patients should Identify touch and recognize different objects with eyes closed.
• Mild Hydrotherapy can be used with caution. It is CI-ed if autonomic nn symptoms are present.
• Neural Mobilizations.
• ADL mods. such as Canes or hand/ crutches may be used depending on compression site/symptoms.