Back to ISAWE Scenarios
paediatric

Obstetric Brachial Plexus Palsy (Erb's Palsy)

advanced
6 min
28 marks
6 questions
Clinical Scenario
A 3-month-old male infant is referred for assessment of his left arm. He was born at term with birth weight 4.5kg following a prolonged second stage and shoulder dystocia. Apgar scores were 6 and 9. The left arm was noted to be flaccid at birth. On examination, the left arm is held adducted at the shoulder with the elbow extended and forearm pronated. There is no active shoulder movement. Active elbow flexion is absent. Hand grasp is present. Moro reflex is asymmetric.
Clinical photograph of a 3-month-old infant with left-sided Erb's palsy. The affected arm is held in the classic 'waiter's tip' position with shoulder adducted, internally rotated, elbow extended, forearm pronated, and wrist flexed. Moro reflex is asymmetric with absent left upper limb response. Active elbow flexion is absent. The hand grasp appears preserved indicating this is an upper trunk (C5-C6) lesion.
Open Full Size

Clinical photograph of a 3-month-old infant with left-sided Erb's palsy. The affected arm is held in the classic 'waiter's tip' position with shoulder adducted, internally rotated, elbow extended, forearm pronated, and wrist flexed. Moro reflex is asymmetric with absent left upper limb response. Active elbow flexion is absent. The hand grasp appears preserved indicating this is an upper trunk (C5-C6) lesion.

Source: Educational illustration of Erb palsy waiter's tip posture • OrthoVellum Medical Education Team • OrthoVellum Educational Use

Questions

Question 1 (4 marks)

Describe the classification of OBPP and identify the injury pattern.

Question 2 (5 marks)

What are the risk factors and describe the birth history assessment?

Question 3 (6 marks)

Explain the clinical examination and how you monitor recovery.

Question 4 (5 marks)

What is the role and timing of primary nerve surgery?

Question 5 (4 marks)

What are the secondary reconstructive procedures?

Question 6 (4 marks)

What is the natural history and prognosis?

Exam Day Cheat Sheet

Must Mention

  • •Erb's = C5-C6 = waiter's tip
  • •Cookie test at 3 months (biceps anti-gravity)
  • •Nerve surgery window 6-9 months
  • •Active Movement Scale (0-7)
  • •Horner's = worst prognosis
  • •Sever-L'Episcopo for IR contracture

Common Pitfalls

  • •Wrong root levels
  • •Missing Horner's
  • •Wrong surgery timing
  • •No cookie test
  • •Confusing primary/secondary
  • •Missing shoulder dysplasia