Medical Conditions

Erb's Palsy (Brachial Plexus Birth Injury)

Medically reviewed by Dr. Michael Okonkwo, MD, FAAP · Board-Certified Neonatologist

Content reviewed against published AAP, NIH guidelines

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If your baby has been diagnosed with or you suspect erb's palsy (brachial plexus birth injury), here is what the evidence says.

The short answer

A brachial plexus injury (Erb's palsy) occurs when the nerves controlling the arm are stretched during delivery, most often during shoulder dystocia. The affected arm may appear limp or have limited movement. The good news is that 80-90% of cases resolve within the first 3-6 months with conservative management and physical therapy.

Key takeaways

  • A brachial plexus injury (Erb's palsy) occurs when the nerves controlling the arm are stretched during delivery, most often during shoulder dystocia. The affected arm may appear limp or have limited movement. The good news is that 80-90% of cases resolve within the first 3-6 months with conservative management and physical therapy.
  • Usually normal when: Gradual improvement in arm movement over the first few weeks to months
  • Call your doctor if: No improvement in arm movement by 3 months, as this is the typical time point for specialist referral and evaluation for potential surgical intervention
  • Varies by age — see the age-by-age breakdown below
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What Parents Should Know

According to AAP, NIH guidelines, a brachial plexus injury (Erb's palsy) occurs when the nerves controlling the arm are stretched during delivery, most often during shoulder dystocia. The affected arm may appear limp or have limited movement. The good news is that 80-90% of cases resolve within the first 3-6 months with conservative management and physical therapy. At 0-1 month, brachial plexus injuries are typically noticed immediately after birth. The affected arm may hang limply at the baby's side, be rotated inward (waiter's tip position), or have limited movement. The baby may not have a Moro reflex on the affected side. Risk factors include large birth weight, shoulder dystocia, and difficult deliveries. Initial management includes gentle handling, avoiding pulling on the affected arm, and early physical therapy to maintain range of motion. Most mild to moderate injuries begin to show improvement within the first few weeks. It is generally considered normal when gradual improvement in arm movement over the first few weeks to months. However, you should contact your pediatrician promptly if no improvement in arm movement by 3 months, as this is the typical time point for specialist referral and evaluation for potential surgical intervention.

Sources: [1], [2]

Normal vs. Concerning

Usually Normal
Worth Discussing
Gradual improvement in arm movement over the first few weeks to months
No improvement in arm movement by 3 months, as this is the typical time point for specialist referral and evaluation for potential surgical intervention
Increasing spontaneous movement of the affected arm
The affected arm appears swollen, discolored, or your baby seems to be in significant pain
Baby beginning to reach and grasp with the affected hand
You want to ensure your baby is receiving appropriate physical therapy

By Age

What to expect by age

0-1 month

Brachial plexus injuries are typically noticed immediately after birth. The affected arm may hang limply at the baby's side, be rotated inward (waiter's tip position), or have limited movement. The baby may not have a Moro reflex on the affected side. Risk factors include large birth weight, shoulder dystocia, and difficult deliveries. Initial management includes gentle handling, avoiding pulling on the affected arm, and early physical therapy to maintain range of motion. Most mild to moderate injuries begin to show improvement within the first few weeks.

1-3 months

Physical therapy continues with gentle range-of-motion exercises to prevent joint stiffness. You will be watching for signs of recovery, including increasing movement of the arm, hand, and fingers. Most babies show significant improvement by 3 months. If there is no improvement in biceps function by 3 months, referral to a specialist (pediatric neurologist or orthopedist) may be recommended to discuss further evaluation and possible surgical options.

3-6 months

If recovery has begun, it typically continues progressively. Babies who show biceps recovery by 3 months have an excellent prognosis for full or near-full recovery. If there has been no improvement by 3-6 months, nerve surgery (such as nerve grafting or transfer) may be considered. This decision is made by a specialized team.

6-12 months

Most babies with mild to moderate injuries have recovered significantly by this age. Those who required surgery typically begin recovering function in the months following the procedure. Ongoing physical and occupational therapy supports optimal function. Even babies with residual weakness often adapt remarkably well.

What to Tell Your Pediatrician

  • Describe when you first noticed erb's palsy (brachial plexus birth injury) and how it has changed over time.
  • Note your baby's current age and which age-specific patterns you are seeing.
  • Mention if you want to ensure your baby is receiving appropriate physical therapy.
  • Mention if you are not seeing improvement in arm movement after the first few weeks.
  • Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
  • Bring a list of any questions or observations you want to discuss at the appointment.

What Should You Do?

When to take action

Probably normal when...
  • Gradual improvement in arm movement over the first few weeks to months
  • Increasing spontaneous movement of the affected arm
  • Baby beginning to reach and grasp with the affected hand
Mention at your next visit when...
  • You want to ensure your baby is receiving appropriate physical therapy
  • You are not seeing improvement in arm movement after the first few weeks
  • You have questions about the expected recovery timeline
Act now when...
  • No improvement in arm movement by 3 months, as this is the typical time point for specialist referral and evaluation for potential surgical intervention
  • The affected arm appears swollen, discolored, or your baby seems to be in significant pain

What You Can Do at Home

  • Keep track of when you notice erb's palsy (brachial plexus birth injury) — noting the time of day, duration, and any triggers can help your pediatrician.
  • Remember that gradual improvement in arm movement over the first few weeks to months — this is generally within the range of normal.
  • At 0-1 month, focus on observation rather than intervention unless your pediatrician advises otherwise.
  • Follow any care instructions from your pediatrician. Keep a written log of symptoms to bring to appointments.
  • While monitoring at home, seek immediate care if no improvement in arm movement by 3 months, as this is the typical time point for specialist referral and evaluation for potential surgical intervention.

Broken Collarbone (Clavicle Fracture) at Birth

A broken clavicle (collarbone) is one of the most common birth injuries, occurring during difficult deliveries, especially in large babies or when shoulder dystocia occurs. While concerning to parents, clavicle fractures in newborns heal very quickly (usually within 2-3 weeks) without any specific treatment. The prognosis is excellent.

Uneven Startle Reflex in Newborns (Asymmetric Moro)

An asymmetric Moro reflex, where one arm responds differently than the other during startle, is an important finding that should be evaluated by your pediatrician. It may indicate a birth injury such as a broken clavicle (collarbone) or brachial plexus injury (Erb's palsy). Early evaluation and treatment lead to the best outcomes.

Early Hand Preference in Newborns (Using One Hand Only)

Babies should not show a strong hand preference before 12-18 months of age. If your newborn or young infant consistently uses one hand much more than the other, or seems to ignore one hand, it could indicate a neurological concern or birth injury that should be evaluated by your pediatrician. True handedness normally develops between 2-4 years of age.

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Guide

When to Call the Doctor

General guide on when to call the pediatrician, visit urgent care, or go to the ER.

Frequently asked questions

Is erb's palsy (brachial plexus birth injury) normal?
A brachial plexus injury (Erb's palsy) occurs when the nerves controlling the arm are stretched during delivery, most often during shoulder dystocia. The affected arm may appear limp or have limited movement. The good news is that 80-90% of cases resolve within the first 3-6 months with conservative management and physical therapy.
When should I call the doctor about erb's palsy (brachial plexus birth injury)?
No improvement in arm movement by 3 months, as this is the typical time point for specialist referral and evaluation for potential surgical intervention The affected arm appears swollen, discolored, or your baby seems to be in significant pain
When is erb's palsy (brachial plexus birth injury) normal?
Gradual improvement in arm movement over the first few weeks to months Increasing spontaneous movement of the affected arm Baby beginning to reach and grasp with the affected hand
What causes erb's palsy (brachial plexus birth injury)?
A brachial plexus injury (Erb's palsy) occurs when the nerves controlling the arm are stretched during delivery, most often during shoulder dystocia. The affected arm may appear limp or have limited movement. The good news is that 80-90% of cases resolve within the first 3-6 months with conservative management and physical therapy. Common explanations include: Gradual improvement in arm movement over the first few weeks to months. Increasing spontaneous movement of the affected arm.
What should I mention to my pediatrician about erb's palsy (brachial plexus birth injury)?
You should mention erb's palsy (brachial plexus birth injury) at your next visit if: You want to ensure your baby is receiving appropriate physical therapy. You are not seeing improvement in arm movement after the first few weeks. You have questions about the expected recovery timeline.
Is erb's palsy (brachial plexus birth injury) normal at 0-1 month?
Brachial plexus injuries are typically noticed immediately after birth. The affected arm may hang limply at the baby's side, be rotated inward (waiter's tip position), or have limited movement. The baby may not have a Moro reflex on the affected side. Risk factors include large birth weight, shoulder dystocia, and difficult deliveries. Initial management includes gentle handling, avoiding pulling on the affected arm, and early physical therapy to maintain range of motion. Most mild to moderate injuries begin to show improvement within the first few weeks.
Is erb's palsy (brachial plexus birth injury) normal at 1-3 months?
Physical therapy continues with gentle range-of-motion exercises to prevent joint stiffness. You will be watching for signs of recovery, including increasing movement of the arm, hand, and fingers. Most babies show significant improvement by 3 months. If there is no improvement in biceps function by 3 months, referral to a specialist (pediatric neurologist or orthopedist) may be recommended to discuss further evaluation and possible surgical options.
Should I go to the ER for erb's palsy (brachial plexus birth injury)?
Seek emergency care if no improvement in arm movement by 3 months, as this is the typical time point for specialist referral and evaluation for potential surgical intervention, or if the affected arm appears swollen, discolored, or your baby seems to be in significant pain. When in doubt, call your pediatrician's after-hours line for guidance.
Does erb's palsy (brachial plexus birth injury) go away on its own?
In many cases, erb's palsy (brachial plexus birth injury) resolves on its own, especially when gradual improvement in arm movement over the first few weeks to months. By 6-12 months, most babies with mild to moderate injuries have recovered significantly by this age. Those who required surgery typically begin recovering function in the months following the procedure. Ongoing physical and occupational therapy supports optimal function. Even babies with residual weakness often adapt remarkably well.
AAPNIH

References

  1. [1]American Academy of Pediatrics. Brachial Plexus Birth Injuries. Pediatrics. AAP
  2. [2]National Library of Medicine. Brachial Plexus Birth Palsy. StatPearls. NIH

Doctor Visit Checklist

Bring this checklist to your next pediatrician visit to discuss Erb's Palsy (Brachial Plexus Birth Injury).

Things to mention

  • Describe when you first noticed erb's palsy (brachial plexus birth injury) and how it has changed over time.
  • Note your baby's current age and which age-specific patterns you are seeing.
  • Mention if you want to ensure your baby is receiving appropriate physical therapy.
  • Mention if you are not seeing improvement in arm movement after the first few weeks.
  • Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
  • Bring a list of any questions or observations you want to discuss at the appointment.

Observations to share

  • You want to ensure your baby is receiving appropriate physical therapy
  • You are not seeing improvement in arm movement after the first few weeks
  • You have questions about the expected recovery timeline

Urgent signs to report immediately

  • No improvement in arm movement by 3 months, as this is the typical time point for specialist referral and evaluation for potential surgical intervention
  • The affected arm appears swollen, discolored, or your baby seems to be in significant pain

My notes

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All content follows our editorial policy and is reviewed against published clinical guidelines.

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Bottom line

Most cases of erb's palsy (brachial plexus birth injury) are normal. Talk to your pediatrician if no improvement in arm movement by 3 months, as this is the typical time point for specialist referral and evaluation for potential surgical intervention.

Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.

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Broken Collarbone (Clavicle Fracture) at Birth

A broken clavicle (collarbone) is one of the most common birth injuries, occurring during difficult deliveries, especially in large babies or when shoulder dystocia occurs. While concerning to parents, clavicle fractures in newborns heal very quickly (usually within 2-3 weeks) without any specific treatment. The prognosis is excellent.

Uneven Startle Reflex in Newborns (Asymmetric Moro)

An asymmetric Moro reflex, where one arm responds differently than the other during startle, is an important finding that should be evaluated by your pediatrician. It may indicate a birth injury such as a broken clavicle (collarbone) or brachial plexus injury (Erb's palsy). Early evaluation and treatment lead to the best outcomes.

Early Hand Preference in Newborns (Using One Hand Only)

Babies should not show a strong hand preference before 12-18 months of age. If your newborn or young infant consistently uses one hand much more than the other, or seems to ignore one hand, it could indicate a neurological concern or birth injury that should be evaluated by your pediatrician. True handedness normally develops between 2-4 years of age.

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