Birth trauma and brachial plexus injury — branching viva

Station opening

Examiner: "Define birth trauma and describe the tissue-system categories of birth injury." [6]

Strong candidate (must-hit)

• Defines birth trauma as any physical injury sustained during the mechanical forces of labour and delivery. Classifies by tissue system: skeletal (clavicle fracture is the most common, followed by femur, humerus, and skull fractures), soft tissue (cephalhaematoma, subgaleal haemorrhage, bruising, lacerations, sternocleidomastoid injury), neurological (brachial plexus birth injury is the most important and most common focal nerve injury, followed by facial nerve palsy, phrenic nerve palsy, and the devastating cervical spinal cord injury), and visceral (adrenal, liver, and splenic haemorrhage). States that brachial plexus birth injury warrants particular attention because of its frequency (~1.5 per 1000 live births), its treatability, and the time-sensitive 3-month surgical threshold. [1] [6]

Weak candidate

• "It's when the baby gets hurt during delivery. The most common is a broken collarbone." [6]

Branch A — The upper-trunk injury and the 3-month threshold

Examiner: "A term newborn after shoulder dystocia holds the right arm adducted, internally rotated, elbow extended, wrist flexed. The Moro is asymmetric. Hand movement is preserved. What is your diagnosis, classification, and management plan?" [2]

Strong

• Diagnoses an upper-trunk (Erb-Duchenne) brachial plexus birth injury involving C5–6 (the waiter's-tip posture), Narakas grade I or II. States the immediate management: gently rest the arm across the chest for 1–2 weeks (no rigid splinting — it causes contracture), palpate the clavicle for fracture, obtain a chest radiograph to exclude clavicle fracture and phrenic nerve palsy, and examine the face and eyes. After the first week, begins gentle passive range-of-motion exercises. Outlines the follow-up: monthly Active Movement Scale, tracking the biceps (elbow flexion) score — antigravity recovery (AMS 5 or above) by 3 months predicts spontaneous recovery and continues conservative management; absent recovery by 3 months (Toronto Score below 3.5) triggers microsurgical nerve reconstruction (grafting and transfer, optimal window 3–9 months). [2] [4]

Weak

• "Splint the arm for a month and see how it goes." [2]

Branch B — The total-plexus injury with Horner syndrome

Examiner: "A different newborn has a completely flail left arm and left-sided ptosis and miosis. What is the significance of these findings, and how does your management differ?" [2]

Strong

• Grades the injury as total-plexus with Horner syndrome — Narakas grade IV, the most severe grade, involving C5 through T1. The Horner syndrome (ptosis, miosis, anhidrosis) signals T1 preganglionic avulsion — the root torn from the spinal cord — a lesion that cannot regenerate. This infant is referred for early specialist assessment before the standard 3-month threshold because the probability of spontaneous recovery is under 30 percent. The surgical pathway differs from the standard grafting approach: avulsed roots cannot be grafted, so extra-plexal nerve transfers (such as intercostal nerves to the musculocutaneous nerve for elbow flexion) are used. Counsels the family honestly about the guarded prognosis and expected residual deficits of the hand. [2] [9]

Weak

• "It's a total palsy — monitor for 3 months and refer if it doesn't recover." [9]

Branch C — The newborn with apnoea and a weak arm

Examiner: "A newborn with a weak right arm is also floppy in the legs and had an apnoeic episode in the first hour. The nurse thinks it's a brachial plexus injury. What is your concern?" [6]

Strong

• States immediately that this is not an isolated brachial plexus injury. Isolated BPBI does not cause leg hypotonia, apnoea, or bulbar weakness. The combination of a weak arm with leg hypotonia and apnoea is cervical spinal cord injury until proven otherwise — a devastating injury that requires urgent MRI of the cervical spine and a completely different management pathway. The error of attributing everything to the arm and missing the cord lesion is catastrophic and avoidable. Orders urgent cervical spine imaging, stabilises the airway and breathing, and involves neonatology and neurosurgery. [6]

Weak

• "It's probably a severe brachial plexus injury — we'll watch and see." [6]

Branch D — The coexisting clavicle fracture

Examiner: "The infant with the upper-trunk injury has a palpable lump on the right clavicle on day 3. How does this change your management?" [6]

Strong

• States that this is a clavicle fracture, the most common skeletal birth injury and a frequent coexisting injury with BPBI. It does not change the brachial plexus management pathway, but it confirms the need for gentle handling and analgesia. Clavicle fractures heal spontaneously with conservative management — no splinting or immobilisation beyond the gentle resting position already used for the BPBI. The family is reassured, and a follow-up radiograph is not routinely needed unless the fracture is angulated or healing is in question. The coexistence underscores the significance of the shoulder dystocia mechanism and the need for thorough newborn examination in every birth-injury case. [6]

Weak

• "We need to splint the clavicle and refer to orthopaedics." [6]

Close

Examiner: "Summarise your approach to the newborn with a brachial plexus injury in one sentence." [2]

Strong

• "A newborn with a waiter's-tip posture and asymmetric Moro has a brachial plexus birth injury — graded by the Narakas system from a mild C5–6 neurapraxia (grade I, near-complete recovery) to a total-plexus avulsion with Horner syndrome (grade IV, poorest) — managed conservatively with physiotherapy and monthly Active Movement Scale, with microsurgical nerve reconstruction when antigravity biceps recovery has not occurred by 3 months (Toronto Score below 3.5), and the coexisting clavicle fracture, phrenic nerve palsy, and the devastating cervical spinal cord injury must each be actively excluded." [2] [4]