Commonest fracture encountered in a baby during delivery?

Appeared in: NORCET-7 Mains-2024

Explanation

Clavicle fractures are the most frequent bone injuries in newborns, occurring in about 5 per 1,000 live births.
The clavicle (collarbone) is anatomically vulnerable to fracture from pressure during passage through the birth canal, especially with shoulder dystocia.
Risk factors include high birth weight (macrosomia), difficult delivery, and instrumental delivery, but it can also occur in uncomplicated births.

Option A: Humerus fractures are rare birth injuries.
Option C: Fractures of the ulna and other forearm bones are extremely rare during delivery.
Option D: Femur fractures are rare birth injuries.

Visual 1: Illustration - A diagram of a newborn's skeleton, highlighting the clavicle, humerus, and femur to provide anatomical context for the potential fracture sites.
Visual 2: Diagram - An illustration depicting the mechanism of shoulder dystocia, showing how the anterior shoulder gets impacted behind the maternal pubic symphysis, which puts direct pressure on the clavicle.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Neonatal Birth Injuries as background academic context rather than a clinical decision trigger.
Nurses play a crucial role in the early detection of clavicle fractures by performing a thorough newborn assessment, checking for crepitus, asymmetry of movement, and an incomplete Moro reflex.
Proper management involves gentle handling of the infant to prevent pain and further injury, along with immobilizing the affected arm by pinning the sleeve to the chest.
A key nursing responsibility is parental education and reassurance. Parents are often distressed, and explaining the common nature of this injury and its excellent prognosis for rapid healing is vital.

How to Approach the Question

Identify the keyword in the question: "Commonest". This indicates you need to find the most frequent or most likely event among the options.
The question asks about fractures during delivery. Consider the mechanics of a baby passing through the birth canal.
Recall or reason that the baby's shoulders are a wide point that must navigate the maternal pelvis after the head emerges. The clavicle (collarbone) is located at the shoulder and is relatively fragile.
Compare this to the other bones. The humerus and femur are stronger long bones in the limbs. A fracture to these bones would likely require significant and direct pulling or twisting forces, which are less common than the compressive forces experienced by the clavicle during a difficult shoulder delivery.
Conclude that the clavicle is the most anatomically vulnerable and therefore the most likely bone to be fractured during delivery.

Concept Tested & Keywords

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