Erb's palsy is a neurological birth injury that affects movement in a baby's shoulder and upper arm. It develops when the upper nerves of the brachial plexus become stretched or damaged. Although many newborns recover substantial arm function, severe injuries can cause lasting weakness and require specialized treatment.
What is Erb's palsy?
Erb's palsy, also called Duchenne-Erb palsy, affects the upper portion of the brachial plexus.
The brachial plexus is a network of nerves extending from the spinal cord through the neck and shoulder into the arm.
These nerves control movement and sensation throughout the upper limb.
Classic Erb's palsy involves the fifth and sixth cervical nerve roots, known as C5 and C6.
These nerves help control shoulder lifting, outward shoulder rotation, and elbow bending.
When they are injured, a newborn may have difficulty raising the affected arm or bending the elbow.
The hand often retains movement because different nerve roots control many hand functions.
The severity varies from temporary nerve stretching to more serious nerve damage.
What causes Erb's palsy during childbirth?
Erb's palsy is frequently associated with difficult deliveries.
One recognized risk factor is shoulder dystocia, an obstetric emergency in which a baby's shoulder becomes obstructed after the head has delivered.
Mechanical forces affecting the baby's head, neck, and shoulder may stretch the brachial plexus.
Other associated circumstances include larger birth weight, breech presentation, and complicated vaginal deliveries.
Some cases occur without documented shoulder dystocia or excessive traction.
For this reason, an Erb's palsy diagnosis does not automatically establish medical negligence.
Recognizing early symptoms
The most recognizable symptom is reduced movement in one arm.
The affected arm may rest close to the baby's body, with the shoulder turned inward and the elbow relatively straight.
This is commonly described as the waiter's tip posture.
Parents may notice that the baby moves one arm normally but rarely lifts the other.
The Moro reflex, or newborn startle response, may be reduced on the affected side.
In classic Erb's palsy, the baby may still grasp a parent's finger.
A newborn with persistent arm weakness should receive prompt medical evaluation.
Diagnosis and treatment
Doctors examine the baby's shoulder, elbow, wrist, and hand movements.
They also assess reflexes and look for associated injuries, including a broken collarbone.
A clavicle fracture can cause pain-related movement restriction, which must be distinguished from nerve weakness.
Specialist evaluation may be recommended when symptoms persist.
Treatment commonly includes physical or occupational therapy to maintain joint flexibility and support functional development.
Children with limited recovery may need evaluation for nerve surgery.
What determines recovery?
Recovery depends on the extent of nerve injury.
Mild stretching injuries often improve during the first months of life.
More severe injuries involving nerve rupture or separation from the spinal cord have a less favorable outlook.
Early improvements in shoulder and elbow movement are encouraging.
However, a child who continues to have significant weakness requires specialist follow-up.
Common questions around Erb's palsy
Can Erb's palsy heal without surgery?
Yes. Many mild cases improve naturally, particularly when nerve continuity remains intact.
Is Erb's palsy always permanent?
No. Recovery varies according to the severity and location of the nerve injury.
Can Erb's palsy affect both arms?
It usually affects one arm, although bilateral injuries can occur.
