Section 122.6: Peripheral Nerve Injuries

Brachial plexus (Erb-Duchenne, Klumpke) · Phrenic nerve paralysis · Facial nerve palsy · Management & prognosis
🤚 Erb's palsy: "waiter's tip" hand · Most recover spontaneously · Surgical referral if no improvement by 3 months

🤕 Neonatal Peripheral Nerve Injuries: Key Syndromes

💪 Erb-Duchenne palsy (C5-C6)
Most common (0.6-4.6/1000 births). "Waiter's tip" arm: adducted, internally rotated, pronated forearm. Biceps reflex absent. 75% recover spontaneously.
🖐️ Klumpke paralysis (C7-T1)
Rare (0.6%). Hand weakness, Horner syndrome (ptosis, miosis, anhidrosis) if T1 involved. Poorer prognosis.
🫁 Phrenic nerve injury
C3-C5, often with Erb's palsy (75%). Causes diaphragmatic paralysis → respiratory distress. Ultrasound shows elevated hemidiaphragm.
😶 Facial nerve palsy (peripheral)
Forceps/vacuum delivery. Entire ipsilateral face, forehead smooth, eye cannot close. Central facial palsy spares forehead.
📊 Mechanism
Lateral traction during shoulder dystocia (vertex) or arm hyperabduction (breech). Macrosomia (birthweight >4000g) major risk factor.
🩺 Treatment & prognosis
Conservative: positioning, passive ROM. Neuroplasty if no improvement at 3 months. Most neurapraxia recovers in weeks.
🔬 Types of nerve injury: Neurapraxia (edema, recovers weeks), Axonotmesis (axon disruption, months), Neurotmesis (complete tear, poor recovery).

🔍 Clinical approach to suspected neonatal peripheral nerve injury

1
Identify risk factors – Shoulder dystocia, macrosomia (>4000 g), breech delivery, vacuum/forceps, prolonged labor.
2
Localize the lesion – Erb's (C5-6): arm adducted, internally rotated, wrist pronated (waiter's tip). Klumpke (C7-T1): hand weakness, Horner. Phrenic: tachypnea, asymmetric diaphragm.
3
Differentiate from central causes – Central facial palsy spares forehead; peripheral facial palsy whole side. Pseudoparalysis from fracture (clavicle/humerus).
4
Diagnostic studies – X-ray to exclude fracture. Ultrasound for diaphragmatic excursion. MRI (nerve root avulsion if surgical candidate).
5
Early management & referral – Passive range of motion, splinting to prevent contractures. Neurology/neurosurgery if no improvement by 3 months.

📋 Stepwise management of peripheral nerve injuries

1
Brachial plexus palsy (Erb's) – Initial conservative management: gentle passive range-of-motion exercises starting day 7-10. Splinting in abduction/external rotation (if needed). Avoid immobilization contractures.
2
Monitoring – Monthly follow-up with motor recovery assessment (biceps, deltoid, wrist extension). Hand grasp preservation is favorable sign.
3
Surgical referral – If no active biceps function by 3 months (or no improvement by 6 months), consider nerve grafting, neurolysis, or neurotization.
4
Phrenic nerve paralysis – Position infant on affected side, oxygen if needed. CPAP may help. Mechanical ventilation in severe cases. Surgical plication if failure to wean by 1-2 months.
5
Facial nerve palsy – Eye care (artificial tears, taping eyelid closed). Prognosis excellent (most recover within weeks). Neuroplasty only if persistent >1 year.
📌 Botulinum toxin: Used for biceps-triceps co-contractions in residual brachial plexus palsy to improve function.

🧠 Rapid reflex prompts – Peripheral nerve injuries

📌 Classic position of Erb's palsy?
Adducted, internally rotated arm, pronated forearm, wrist flexed ("waiter's tip").
📌 Which nerve roots are injured in Erb-Duchenne?
C5, C6 (± C7 in 50%).
📌 Horner syndrome in newborn suggests?
Klumpke paralysis (C7-T1 injury, sympathetic fibers T1). Ptosis, miosis, anhidrosis.
📌 What percent of brachial plexus injuries recover spontaneously?
~75% (neurapraxia/axonotmesis). Surgical referral if no biceps by 3 months.
📌 How to differentiate peripheral vs central facial palsy?
Peripheral: forehead smooth, eye cannot close (entire side). Central: forehead sparing (bilateral cortical innervation).
📌 Most common nerve injured in phrenic palsy?
C3-C5 (phrenic nerve) – often associated with ipsilateral Erb's palsy (75%).
ocument.getElementById('revealAllBtn')?.addEventListener('click',revealAllCards); document.getElementById('hideAllBtn')?.addEventListener('click',hideAllCards); }); eout(() => { if (statDiv) statDiv.innerHTML = '✓ Saved'; }, 1500); } } }); }); } function initTabs() { const btns = document.querySelectorAll('.tab-btn'); btns.forEach(btn => { btn.addEventListener('click', () => { const target = btn.getAttribute('data-tab'); btns.forEach(b => b.classList.remove('active')); btn.classList.add('active'); document.querySelectorAll('.tab-content').forEach(t => t.classList.remove('active-tab')); document.getElementById(`tab-${target}`).classList.add('active-tab'); }); }); } function init() { loadFeynmanStorage(); renderMCQs(); renderFeynman(); initTabs(); document.getElementById('submitQuizBtn')?.addEventListener('click', submitQuiz); document.getElementById('resetQuizBtn')?.addEventListener('click', resetQuiz); } init();