01Approach to the Critical Patient/attcp32

Immediate priorities

›Alarm features requiring urgent action

›Open fracture with radial nerve deficit

›Suggests neurotmesis requiring urgent surgical exploration within 72 hours

›Coordinate orthopedic and peripheral nerve surgery

›Vascular compromise with nerve deficit

›Absent radial pulse or expanding hematoma

›Associated brachial artery injury in humeral fractures

›Activate vascular surgery immediately

›Progressive deficit after fracture fixation

›Iatrogenic radial nerve injury

›Urgent surgical re-exploration

›Bilateral wrist drop

›Central lesion, lead poisoning, or multifocal motor neuropathy

›Immediate neurological assessment

›Wrist drop with constitutional symptoms

›Fever, weight loss, night sweats — suspect malignancy or nerve sheath tumor

›Urgent oncology evaluation

Hemodynamic and stabilization targets

›Polytrauma with radial nerve injury

›Airway, breathing, circulation priorities before nerve evaluation

›SBP target > 90 mmHg

›Two large-bore IV access

›Hemorrhage control before splinting

›Limb stabilization

›Immobilize associated humeral fracture immediately

›Volar cock-up wrist splint 20-30 degrees extension

›Neurovascular checks distal to injury every 30-60 minutes

02History/hx54

Mechanism and onset

›Mechanism of injury

›Trauma: fracture, laceration, gunshot wound, penetrating injury

›External compression: sleeping with arm over chair (Saturday night palsy), crutch use, tourniquet

›Iatrogenic: surgical positioning, ORIF of humerus, intramuscular deltoid injection

›Repetitive activity: forearm pronation/supination in radial tunnel syndrome

›Onset characterization

›Hyperacute within 24 hours: traumatic or compressive

›Subacute or chronic: entrapment, tumor, or systemic neuropathy

›Waking with deficit: classic for Saturday night palsy

›Immediately post-fracture: direct nerve injury versus entrapment

Symptom characterization

›Motor symptoms

›Inability to extend wrist (wrist drop)

›Inability to extend fingers at MCP joints (finger drop)

›Difficulty gripping objects despite paradoxically preserved grip strength at neutral wrist

›Isolated finger drop without wrist drop: suggests PIN syndrome

›Sensory symptoms

›Numbness or tingling over dorsal hand and posterior forearm

›Pure sensory loss over dorsal radial hand: superficial radial nerve or handcuff neuropathy

›Pain predominant without weakness: radial tunnel syndrome

›Temporal features

›Sudden onset after waking: compressive etiology

›Progressive weakness over months: tumor, multifocal motor neuropathy

›Preceded by acute severe arm pain: neuralgic amyotrophy (Parsonage-Turner)

Risk factors and context

›Key risk factors

›Humeral shaft fracture, especially middle to distal third: 8.5-16% incidence radial nerve palsy

03Physical Exam/exam44

Motor examination

›Systematic muscle testing by nerve branch level

›Triceps (elbow extension): main trunk proximal to spiral groove

›Weakness indicates lesion at or above axilla

›Involved in 22-49% of arm-level lesions

›Brachioradialis (elbow flexion in semipronation): main trunk distal to spiral groove

›Full recruitment is the single best prognostic marker

›Full brachioradialis recruitment predicts 100% good outcome

›ECRL (wrist extension with radial deviation): main trunk

›Spared in PIN syndrome: differentiates from radial nerve main trunk lesion

›Extensor digitorum communis (finger extension at MCP): posterior interosseous nerve

›Most frequently affected muscle in PIN syndrome

›Extensor indicis proprius (index finger extension): PIN most distal branch

›Supinator (forearm supination): PIN involvement in radial tunnel syndrome

›MRC grading of wrist and finger extension

›Grade 0: no contraction

›Grade 3: movement against gravity

›Grade 4: movement against resistance

›Grade 5: normal power

›Functional wrist and hand assessment

›Wrist drop with gravity-eliminated and against-gravity testing

›Grip strength with wrist in neutral versus supported extension

Sensory examination

›Sensory distribution testing

›Posterior forearm and dorsal hand: main trunk radial nerve lesion

›Dorsal radial hand only: superficial radial nerve or handcuff neuropathy

›No sensory loss: pure PIN syndrome (sensory branch spared)

›Dermatomal C7 distribution: if cervical radiculopathy considered

04Differential Diagnosis/ddx46

Peripheral nerve localization

›Radial nerve main trunk at spiral groove

›Wrist drop, finger drop, sensory loss over dorsal hand and posterior forearm

›Triceps usually spared in mid-humeral injuries

›ICD-10: G54.2 (cervical root disorders), S54.2 (injury of radial nerve at forearm level)

›Posterior interosseous nerve (PIN) syndrome

›Finger drop without wrist drop (ECRL spared)

›No sensory loss (purely motor branch)

›Often caused by lipoma, synovitis, or radiocapitellar ganglion

›ICD-10: G56.3 (lesion of radial nerve)

›Superficial radial nerve neuropathy

›Pure sensory: numbness over dorsal radial hand

›No motor deficit

›Caused by handcuffs, tight watch, forearm cast

Proximal nerve and plexus lesions

›Posterior cord brachial plexopathy

›Radial nerve distribution plus deltoid and axillary nerve weakness

›Distinguishes from isolated radial nerve injury by deltoid involvement

›ICD-10: G54.0 (brachial plexus disorders)

›C7 radiculopathy

›Wrist drop with radial deviation weakness but also median-innervated muscle involvement

›Triceps reflex diminished

›Neck pain with dermatomal C7 sensory loss

›Pronator teres and FCR involved (distinguishes from radial nerve)

›ICD-10: M54.12 (radiculopathy, cervical region)

Mimics and systemic causes

›Multifocal motor neuropathy (MMN)

›Chronic progressive finger and wrist extension weakness

05Laboratory Tests/lt21

Routine workup

›Targeted lab evaluation

›Routine labs not required for isolated traumatic radial nerve injury with clear mechanism

›Complete blood count if infection, inflammation, or malignancy suspected

›Comprehensive metabolic panel for systemic disease screening

›ESR and CRP for inflammatory or infectious etiology

Metabolic and toxic screen

›Metabolic causes

›HbA1c or fasting glucose: diabetes screening in unexplained neuropathy

›TSH: hypothyroid neuropathy

›Vitamin B12 with methylmalonic acid: deficiency-related neuropathy

›Thiamine level: alcohol-related neuropathy

›Serum protein electrophoresis with immunofixation: monoclonal gammopathy

›Toxic and immune causes

›Blood lead level: bilateral wrist drop workup

›Level greater than 1.9 mmol/l (40 mcg/dL) associated with neuropathy

›Anti-GM1 ganglioside antibodies: multifocal motor neuropathy

›ANA, RF, anti-CCP: rheumatologic etiology (synovitis causing PIN compression)

Rhabdomyolysis screening

›If crush injury or prolonged compression

›Creatine kinase (CK): significantly elevated in rhabdomyolysis

›Urine myoglobin

›Serum creatinine for renal function

›Electrolytes including potassium

06Diagnostic Tests/dt76

Scoring Systems

›Seddon-Sunderland nerve injury classification

›Sunderland Grade I (Neurapraxia): demyelination only, axons intact

›Full recovery within 3 months

›Best prognosis: compressive and Saturday night palsy injuries

›Sunderland Grade II (Axonotmesis): axon loss, endoneurium intact

›Full recovery at rate of 1 mm per day from injury site

›Prognostication by distance from injury to target muscle

›Sunderland Grade III: axon and endoneurium disrupted

›Partial recovery, variable outcome

›Sunderland Grade IV: axon, endo, and perineurium disrupted

›Poor prognosis without surgery

›Sunderland Grade V (Neurotmesis): complete nerve transection

›No recovery without surgical repair

›Mackinnon Grade VI: mixed injury pattern

›Variable outcome, may require surgery

›MRC (Medical Research Council) grading scale

›Used for serial motor assessment and recovery tracking

›Grade 3 (movement against gravity) as threshold for meaningful functional recovery

›M4+ defined as movement against resistance: target for surgical outcomes reporting

›Prognosis score for humeral fracture-associated palsy

›Recovery probability: if no recovery by 7 months, 56% chance of recovery by 18 months

›If not recovered by 12 months, probability of recovery drops to 17%

›Early surgical exploration within 3 weeks: 89.8% recovery rate

›Nonsurgical management: 77.2% recovery rate

›Late surgical exploration: 68.1% recovery rate

MRI

›MRI arm and forearm

›Indications: suspected space-occupying lesion causing nerve compression

›Lipoma, nerve sheath tumor, ganglion cyst at radial tunnel

›Perineural fibrosis, synovitis at lateral elbow

›Protocol: T1 and T2 sequences, axial and coronal planes

›Findings: nerve signal hyperintensity indicates axonal injury or edema

›Muscle denervation pattern on T2: timing parallels Wallerian degeneration

›MRI cervical spine

›Indications: suspected C7 radiculopathy in differential

›Neck pain, bilateral or proximal involvement, dermatomal sensory loss

›Protocol: sagittal T2, axial T2/gradient echo

›Findings: disc herniation or foraminal stenosis at C6-7

CT

›CT humerus

›Plain radiograph is first-line; CT reserved for complex fractures

›Indications: comminuted fracture, intraarticular extension, pre-operative planning

›Protocol: thin cuts with 3D reconstruction for operative planning

›Key findings: fracture pattern at mid-to-distal spiral groove zone

›Middle-to-distal third fractures carry highest radial nerve risk

›CT angiography

›Indications: suspected brachial artery injury concurrent with nerve injury

›Absent or diminished radial pulse, expanding hematoma

›Protocol: CTA of upper extremity with arterial phase

›Findings: arterial occlusion, pseudoaneurysm, intimal injury

Ultrasound

›Neuromuscular ultrasound

›Point-of-care utility: direct visualization of radial nerve

›Normal nerve: fascicular honeycomb pattern on short axis

›Injury: enlarged cross-sectional area, loss of fascicular pattern, neuroma in continuity

›Indications:

›Localize nerve injury or compression site

›Identify space-occupying lesion (lipoma, ganglion)

›Guide nerve block for pain management

›Assess nerve continuity before operative decision

›Technique: trace radial nerve from axilla to forearm at radial tunnel

›Normal cross-sectional area at spiral groove: 9-12 mm squared

›Cross-sectional area greater than 10 mm squared at compression site: abnormal

›Advantages over MRI: real-time, dynamic assessment, no contraindications

›Limitations: operator-dependent, limited soft tissue contrast

›Electrodiagnostic studies (EDX) — cornerstone of evaluation

›Optimal timing: at least 3-4 weeks post-injury for diagnostic accuracy

›Wallerian degeneration manifest by day 7-10 on NCS

›Fibrillation potentials and positive sharp waves appear at 3-4 weeks on EMG

›Nerve conduction studies (NCS):

›Radial motor NCS recording from EIP and EDC

›Assess for conduction block across the spiral groove

›Reduced CMAP amplitude indicates axon loss

›Conduction block with preserved distal amplitude: neurapraxia (favorable)

›Needle EMG:

›Sample EIP, EDC, brachioradialis, ECRL, triceps

›Sample non-radial C7 muscles: pronator teres, FCR

›Sample cervical paraspinals to exclude radiculopathy

›Full brachioradialis recruitment predicts 100% good outcome

07Disposition/dispo22

Admission criteria

›Indications for admission

›Associated humeral fracture requiring operative fixation

›Open fracture with nerve deficit requiring urgent surgical exploration

›Polytrauma with radial nerve injury

›Vascular compromise requiring urgent intervention

›Progressive deficit after fracture fixation (iatrogenic injury)

›Systemic cause requiring inpatient workup (malignancy, severe lead toxicity)

Discharge criteria

›Safe for discharge

›Isolated compressive radial neuropathy (Saturday night palsy) without fracture

›Clear compressive mechanism with expected recovery trajectory

›Neurovascular exam stable

›Adequate pain control and cock-up wrist splint in place

›Reliable follow-up arranged with neurology or hand surgery

Observation indications

›Short-stay monitoring

›New-onset radial nerve palsy after fracture reduction

›Monitor for progression over 4-6 hours before discharge decision

›Uncertain mechanism requiring initial workup results

Specialist follow-up

›Outpatient referral planning

›Neurology or electrodiagnostic medicine: EDX at 3-4 weeks post-injury

›Hand or peripheral nerve surgery: if no improvement at 3 months

›Orthopedic surgery: humeral fracture management and serial nerve checks

›Occupational therapy: early splinting, passive ROM, functional training

08Treatment/t70

Immediate splinting and protection

›Orthotic management

›Volar cock-up wrist splint

›Wrist in 20-30 degrees extension

›MCP joints in slight flexion

›Prevents wrist flexion contracture

›Improves functional grip by maintaining wrist in extension

›Dynamic wrist-hand orthosis for active rehabilitation phase

›Allows gravity-assisted finger extension

›Facilitates reinnervation-guided strengthening

›Fracture immobilization

›Coaptation splint or hanging arm cast for humeral shaft fractures

›Avoid any compression over the spiral groove during splinting

Pain management

›Nociceptive pain

›NSAIDs: ibuprofen 400-600 mg orally every 6-8 hours

›With food to reduce gastrointestinal side effects

›Maximum 2400 mg per 24 hours

›Acetaminophen 500-1000 mg orally every 6-8 hours

›Maximum 4000 mg per 24 hours

›Preferred if NSAIDs contraindicated

›Neuropathic pain

›Gabapentin

›Starting dose: 300 mg orally at night

›Titrate to 300-600 mg three times daily over 1-2 weeks

›Maximum 3600 mg per day

›Dose-reduce for renal impairment

›Pregabalin

›Starting dose: 75 mg orally twice daily

›Titrate to 150-300 mg twice daily over 1-2 weeks

›Maximum 600 mg per day

›Radial tunnel syndrome specific

›Corticosteroid injection: diagnostic and therapeutic

›Methylprednisolone 40 mg with 1-2 mL lidocaine 1%

›Injection at point of maximum tenderness 4-5 cm distal to lateral epicondyle

›Activity modification and wrist extension splinting

Conservative management

›Non-surgical first-line approach

›Avoidance of repeat compression or provocative positioning

›Alcohol cessation counseling for Saturday night palsy

›Physical and occupational therapy referral

›Passive ROM to prevent contractures: daily wrist, finger, and elbow exercises

›Progressive strengthening as reinnervation occurs

›Functional retraining and assistive device training

›Expected recovery: Saturday night palsy nearly 100% effective at 6 months with conservative care

Surgical management

›Surgical intervention indications

›Open injury with suspected neurotmesis

›No clinical or EDX recovery at 3-4 months post-injury

›Progressive deficit despite conservative management

›Space-occupying lesion identified on imaging

›Optimal timing for nerve repair: within 6-7 months of injury

›Neurolysis

›For lesions in continuity with favorable EDX (conduction block)

›98% achieved motor recovery greater than or equal to Grade 3

›Class IIa recommendation based on series evidence

›Primary or secondary nerve repair

›Direct end-to-end repair for short nerve gaps

›83-91% good outcomes in series data

›Nerve grafting

›Sural nerve graft for defects greater than 2-3 cm

›Optimal timing: 6.9 months or less post-injury

›Shorter defect length and more graft cables predict better outcome

›Nerve transfer

›Median nerve branches (FCR, FDS motor branches) to PIN and ECRB

›M4+ wrist extension achieved in all patients in case series

›Optimal timing: within 6 months of injury

›Preferred for proximal injuries with long regeneration distance

›Tendon transfer

›Gold standard for late or irreversible radial nerve palsy

›PT to ECRB for wrist extension

›FCU or FCR to EDC for finger extension

›FDS to EPL and EPB for thumb extension

›Faster recovery than nerve procedures but no independent finger function

09Special Populations/sp65

Pregnancy

›Physiologic considerations in pregnancy

›Increased fluid retention can exacerbate nerve compression syndromes

›Radial nerve compression from positioning during labor and delivery

›Saturday night palsy equivalent from prolonged arm positioning during delivery

›Medication safety

›NSAIDs: avoid after 20 weeks gestation due to premature ductus arteriosus closure

›Short-term use before 20 weeks acceptable if benefits outweigh risks

›Acetaminophen: preferred analgesic in pregnancy at standard doses

›Gabapentin: limited safety data, crosses placenta

›Use only if benefits clearly outweigh risks

›Discuss with obstetrics before prescribing

›Pregabalin: contraindicated in pregnancy

›Management approach in pregnancy

›Splinting and conservative measures first-line

›Corticosteroid injection: acceptable if indicated; use lowest effective dose

›Imaging: ultrasound preferred; MRI without gadolinium if needed

›EDX studies safe in pregnancy with appropriate precautions

Geriatric

›Age-related considerations

›Increased susceptibility to compressive neuropathy with thinner soft tissue protection

›Higher prevalence of diabetes and peripheral neuropathy baseline

›Prolonged recovery compared to younger patients

›Higher risk of falls from functional hand weakness

›Medication adjustments

›Gabapentin: start at 100-200 mg at night due to increased sedation risk

›Titrate slowly with geriatric fall risk reassessment

›Increased risk of dizziness, ataxia, and cognitive effects

›Pregabalin: start at 25-50 mg twice daily

›NSAIDs: use with caution due to renal function decline and GI bleeding risk

›Prefer acetaminophen as first-line analgesic

›Avoid opioids as primary pain management; fall risk

›Fracture management considerations

›Higher incidence of osteoporotic humeral fractures

›Bone quality affects surgical fixation planning

›Early mobilization to prevent deconditioning

›Reassess living situation and home support during recovery

›Recovery expectations

›Nerve regeneration may be slower due to age-related axonal changes

›Denervation atrophy more pronounced in elderly

›Functional recovery may plateau at lower MRC grades

Pediatrics

›Pediatric-specific etiologies

›Birth-related radial nerve palsy: focal compression during delivery

›Usually compressive (neurapraxia), not traction injury

›Spontaneous resolution expected within 3-5 months

›No urgent surgical intervention required in uncomplicated cases

›Monteggia fracture-dislocation: radial head dislocation compressing PIN

›Associated with ulnar fracture

›Surgical reduction of radial head often resolves PIN palsy

›Supracondylar humerus fracture: anterior interosseous nerve more commonly

›Sports injuries: arm wrestling fractures in adolescents

›Weight-based dosing considerations

›Ibuprofen: 10 mg per kg orally every 6-8 hours

›Maximum 40 mg per kg per day, maximum single dose 800 mg

›Acetaminophen: 15 mg per kg orally every 4-6 hours

›Maximum 75 mg per kg per day, maximum 4000 mg per day

›Gabapentin: 5 mg per kg per day divided three times daily

›Titrate over 3 days to 10-35 mg per kg per day

›Adjust for age and renal function

›Imaging considerations

›X-ray first-line for fracture assessment

›MRI preferred over CT to avoid radiation in children

›Sedation may be required for MRI in young children

›Prognosis in pediatrics

›Birth palsy and compressive injuries: excellent prognosis

›EDX optimal at 3-4 weeks as in adults

›Surgical referral if no recovery by 3-4 months

10Background/b67

Epidemiology

›Incidence and prevalence

›Radial nerve is the most commonly injured nerve in peripheral nerve trauma

›External compression accounts for 40% of cases

›Humeral fractures account for 18% of cases

›Spiral groove (arm level) is the most common injury site: 89% in large series

›Incidence of radial nerve palsy with humeral shaft fractures: 8.5-16%

›Arm wrestling with humeral fracture: 26-28% incidence of radial nerve palsy

›Demographics and risk profile

›Male predominance in both traumatic and nontraumatic groups

›Saturday night palsy associated with alcohol intoxication and substance use

›Occupational injuries prominent in manual labor and repetitive work

›177-patient series (Sinthuwong and Katirji, 2026): largest prospective EDX-characterized cohort

›Prognosis overview

›Spontaneous recovery in 77-90% of humeral fracture-associated palsies

›Compressive (Saturday night palsy): excellent prognosis, near 100% recovery

›Nontraumatic compressive radial neuropathies: approximately 90% good outcome

Pathophysiology

›Nerve anatomy

›Radial nerve: C5-T1, posterior cord of brachial plexus

›Enters arm via triangular interval between teres major and long head of triceps

›Courses in spiral groove of humerus: point of maximal vulnerability

›Divides at lateral epicondyle into superficial radial nerve and PIN

›PIN enters posterior compartment through Arcade of Frohse (fibrous arch of supinator)

›Injury mechanisms

›Neurapraxia (Grade I): focal demyelination without axon loss

›Compression causes focal ischemia and myelin sheath disruption

›Recovery within 6-12 weeks without axon regeneration required

›Axonotmesis (Grade II): axon loss with intact endoneurium

›Wallerian degeneration distal to injury site occurs over 7-10 days

›Regeneration at 1 mm per day from injury site toward target muscle

›Neurotmesis (Grade V): complete nerve transection

›No spontaneous recovery possible

›Surgical approximation required

›Wallerian degeneration timeline

›24-72 hours: sodium channel disruption, early axon dysfunction

›7-10 days: myelin and axon debris apparent on NCS (CMAP amplitude falls)

›14-21 days: Schwann cells dedifferentiate, macrophage infiltration

›21-28 days: fibrillation potentials and positive sharp waves on needle EMG

›PIN entrapment at Arcade of Frohse

›Fibrous arch compresses PIN at proximal supinator

›Lipoma, synovitis, ganglion, and radiocapitellar pathology contribute

›Radial tunnel is 5 cm segment from radial head to proximal supinator

Therapeutic Considerations

›Conservative versus surgical decision framework

›Trial of conservative management for 3-4 months in closed injuries

›EDX at 3-4 weeks guides prognosis and surgical planning

›Brachioradialis recruitment on initial EDX: single best prognostic indicator

›Conduction block on NCS: favors neurapraxia with expected recovery

›Absent CMAP with denervation on EMG: favors axonotmesis or worse

›Nerve regeneration biology

›Rate: 1 mm per day or approximately 1 inch per month

›Tinel sign advancement confirms regeneration front

›Advancing Tinel at 4-week intervals confirms expected recovery trajectory

›Reinnervation order: proximal to distal, brachioradialis before intrinsic hand

›Timing principles for surgical intervention

›Open injuries: exploration within 72 hours

›Closed injuries: initial observation 3-4 months, surgery if no recovery

›Nerve grafting optimal within 6.9 months; outcomes worsen with delay

›Nerve transfer preferred when target muscle denervation exceeds 12 months

›Tendon transfer when nerve recovery window has closed

›Electrodiagnostic utility

›Initial EDX at 3-4 weeks: optimal for injury severity classification

›Serial EDX at 3-month intervals: track reinnervation and guide surgical timing

›EDX guides selection of neurolysis versus repair versus transfer

›Rehabilitation principles

›Passive ROM from day 1 to prevent joint contractures

›Splinting maintains functional position during reinnervation

›Electrical stimulation: evidence limited but may reduce denervation atrophy

›Biofeedback and sensory re-education for incomplete recovery

11Patient Discharge Instructions/pdi36

copy discharge instructions

›Diagnosis and overview

›You have been diagnosed with a radial nerve injury

›The radial nerve controls wrist and finger extension and sensation on the back of the hand

›Most radial nerve injuries recover with time, splinting, and physiotherapy

›Recovery can take weeks to months depending on the type and severity of injury

›Splint care

›Wear the wrist splint at all times unless bathing or doing exercises

›The splint keeps your wrist in the right position to prevent tightening of the tendons

›Do not allow the wrist to drop unsupported; this causes contracture

›Contact your provider if the splint causes pain, pressure sores, or swelling

›Activity and positioning

›Avoid sleeping with arm hanging over a chair, sofa arm, or hard surface

›Avoid any pressure on the back of the upper arm for prolonged periods

›Alcohol can cause or worsen nerve compression; avoid alcohol during recovery

›Return to work or sport only as directed by your specialist

›Exercise instructions

›Perform passive wrist extension and finger extension exercises daily

›Use opposite hand to gently extend wrist 10 times, three times per day

›Gently straighten each finger using other hand, 10 repetitions per digit

›Do not force through significant pain during exercises

›Attend all physiotherapy and occupational therapy appointments

›Medication instructions

›Take pain medication as prescribed

›Do not exceed recommended doses of ibuprofen or acetaminophen

›Report any dizziness, confusion, or excessive drowsiness from nerve pain medications

›Follow-up appointments

›Attend outpatient appointment with neurology or hand surgery as scheduled

12References/r29

Guidelines and key sources

›Sinthuwong C, Katirji B. Radial Mononeuropathy: Clinical and Electrodiagnostic Characteristics in 177 Patients. Muscle and Nerve. 2026

›Largest prospective EDX-characterized cohort; spiral groove most common site (89%)

›External compression 40%, humeral fractures 18% of cases

›Brachioradialis full recruitment: 100% good outcome predictor

›Ilyas AM, Mangan JJ, Graham J. Radial Nerve Palsy Recovery With Fractures of the Humerus: An Updated Systematic Review. Journal of the American Academy of Orthopaedic Surgeons. 2020

›Spontaneous recovery 77-90% of fracture-associated palsies

›Early exploration within 3 weeks: 89.8% recovery rate

›Recovery probability falls sharply after 12 months without improvement

›Schwaiger K, Abed S, Russe E, et al. Management of Radial Nerve Lesions After Trauma or Iatrogenic Nerve Injury: Autologous Grafts and Neurolysis. Journal of Clinical Medicine. 2020

›Neurolysis: 98% achieved grade 3 or greater motor recovery

›Primary or secondary repair: 83-91% good outcomes

›Nerve grafting optimal timing 6.9 months or less post-injury

›Silver S, Ledford CC, Vogel KJ, Arnold JJ. Peripheral Nerve Entrapment and Injury in the Upper Extremity. American Family Physician. 2021

›Conservative management guidelines and surgical indications

›PIN syndrome differentiating features and management

›Robinson LR. How electrodiagnosis predicts clinical outcome of focal peripheral nerve lesions. Muscle and Nerve. 2015

›EDX prognostic criteria and outcome prediction framework

›Conduction block as favorable prognostic sign

›Steenbeek ED, Pondaag W, Tannemaat MR, et al. Optimal timing of needle electromyography to diagnose lesion severity in traumatic radial nerve injury. Muscle and Nerve. 2023

›EMG optimal at 3-4 weeks for fibrillation potentials and severity classification

›Krijnen NA, Comerci AJ, Head LK, et al. What Is the Probability of Radial Nerve Recovery After Surgical Repair of Humerus Fractures Accounting for Time Since Injury? Clinical Orthopaedics and Related Research. 2026

›Recovery probability falls to 17% if no recovery by 12 months post-injury

›Ahmed KS, Rajput BU, Siddiqui MAI, Nadeem A, Rahman MF. Median to Radial Nerve Transfer: An 8-Year Experience. Journal of Surgical Research. 2023

›M4+ wrist extension in all patients after median to radial nerve transfer

›Optimal timing within 6 months of injury

›Bateman EA, Pripotnev S, Larocerie-Salgado J, Ross DC, Miller TA. Assessment, management, and rehabilitation of traumatic peripheral nerve injuries for non-surgeons. Muscle and Nerve. 2025

›Rehabilitation framework and non-surgical management principles

Evidence & Review

Evidence & Review