Brachial plexus birth injury

How does this happen?

Five nerve roots leave the spinal cord in the neck, at levels C5 through T1. They join, split and rejoin into a network, then travel down the arm. Each level supplies a different part.

• C5 and C6 supply the shoulder and the bending of the elbow.
• C7 supplies the straightening of the elbow and the wrist.
• C8 and T1 supply the hand.

During birth, the head and the shoulder can be pushed apart, stretching this bundle. If the stretch is enough, nerves are injured, and which ones decides what the arm can do. ³

The four kinds of nerve injury

This matters more than the name of the palsy, because it decides recovery.

• neurapraxia. The nerve is stretched but intact. It recovers, usually in weeks to a few months. This is the most common and the best outcome.
• Axonotmesis. The nerve fibers are damaged but the outer sheath is intact, so fibers can regrow along the original path. Recovery takes months and is often incomplete.
• neuroma. Scar tissue forms where the nerve was torn. Signals cross it poorly and recovery is limited.
• avulsion. The root is torn away from the spinal cord. It cannot recover on its own and it cannot be repaired by joining it back. Function can sometimes be restored by moving a different nerve to do the job, called a nerve transfer. ¹

A single baby can have different injury types at different levels. That is why an arm can regain shoulder movement and never regain hand function, or the reverse.

Why the first months matter

Nerves regrow slowly. A muscle that receives no nerve signal for too long loses the ability to respond even if the signal eventually arrives. That window is the reason surgical teams work to a timetable rather than waiting indefinitely. ¹

What causes it?

Two different questions get mixed together here. The first is what leads to this injury in the body. The second is whether anyone could have prevented it. They are not the same question, and the answer to the first does not settle the second.

Happens even with perfect care

• shoulder dystocia that was managed correctly. The maneuvers used to free a stuck shoulder are themselves forceful, and injury can occur despite correct technique. Guidance states this directly. ²
• The forces of labor itself, including in births with no shoulder dystocia recorded.
• Cesarean birth, where these injuries also occur, which shows they are not exclusively a traction phenomenon. ²
• A large baby, which raises risk and cannot be measured accurately before birth. Ultrasound estimates of fetal weight have substantial error. ⁴
• Maternal diabetes, which affects the way weight is distributed on the baby. ⁵
• A very fast second stage, or a breech birth.
• Injury before labor, which has been documented in a small number of cases.

Associated with gaps in care

These are situations where published standards say what the care team should watch for and do. A gap here does not prove anyone caused your child's injury. It points to where the medical records will have an answer.

• A shoulder dystocia managed outside the recognized sequence. There is a defined set of maneuvers, beginning with the McRoberts maneuver and suprapubic pressure. Fundal pressure, meaning pressure on the top of the uterus, is specifically discouraged because it worsens impaction. ²
• Excessive traction on the head. Guidance addresses the amount and direction of traction during a shoulder dystocia. ²
• Risk factors not considered. Guidance addresses when cesarean may be offered for suspected macrosomia, and what the limits of ultrasound weight estimates are. ⁴
• Gestational diabetes not screened for or not managed. ⁵
• The event not documented. A shoulder dystocia should be recorded with the maneuvers used, in order, with times. A missing or thin note is a real problem for a family trying to understand what happened.
• The injury not recognized after birth, or the baby discharged without an arm examination. Newborn examination before discharge is standard practice. ⁶
• Referral delayed past the surgical window, so the option of nerve surgery was lost. ¹

Whether any of this amounts to a departure from the standard of care takes a physician expert reading the whole record. Brachial plexus injuries occur after correctly managed births, and guidance says so plainly. ²

What are the signs, by age?

Signs change as a child grows. A newborn cannot show you a walking problem. Some children look fine at first and show differences months later.

At birth and the first hours

• An arm that lies limp at the baby's side.
• No startle response on that side.
• The arm turned inward with the palm facing backward, which is the classic posture of the upper-nerve pattern.
• A hand that grips normally, in upper injuries, which sometimes reassures people wrongly.
• Sometimes a broken clavicle on the same side.
• Breathing difficulty, if the nerve to the diaphragm is affected. This needs urgent assessment.

The first week

• Continued lack of movement.
• A droopy eyelid and a smaller pupil on the same side, called Horner syndrome, which suggests a lower root injury and a more severe picture.
• Absent startle on one side.

Around 3 months

• Return of shoulder and elbow movement in babies who are recovering well. This is the expected timeline. ¹
• Persistent lack of elbow bending against gravity, which is a warning sign.
• Early stiffness at the shoulder.

Around 6 months

• This is the checkpoint. A baby without meaningful shoulder and elbow function by now should be under specialist review, if they are not already. ¹
• Tightness in the shoulder, limiting outward rotation.
• Using only the other hand.

Around 12 months

• Ongoing weakness, often at the shoulder.
• A shorter arm on the affected side.
• Shoulder joint changes from long-standing muscle imbalance, which is a reason for continued specialist follow-up.

Toddler years

• Difficulty raising the arm overhead.
• Difficulty turning the palm upward.
• Using the mouth or the other hand to help.
• Frustration during two-handed tasks.

School age

• Functional limits in sport, dressing and self-care.
• Arm length difference.
• Shoulder problems that may need surgery.
• Awareness of difference, and the social side of that.

How is it diagnosed?

The diagnosis is clinical: a newborn whose arm does not move normally.

The examination determines which nerve levels are affected, by watching what the baby can and cannot do. Shoulder, elbow, wrist and hand are assessed separately. This is repeated over time, because the pattern of return is what guides treatment. ¹

Imaging is done to rule out other causes and to plan surgery.

• X-ray of the shoulder and collarbone, to look for a clavicle fracture or a bone injury, and of the chest if diaphragm involvement is suspected.
• MRI of the brachial plexus, usually if surgery is being considered, to look for root avulsion.
• Ultrasound of the shoulder to assess joint position in older infants.

Electrical studies such as nerve conduction and electromyography are used in some centers to help judge how much nerve is working.

The distinction that decides everything

The critical question is not the label but whether function is returning, and how fast. Serial examinations by the same team, using a standardized scale, are far more informative than a single assessment.

When to seek a specialist

Any baby with a brachial plexus injury should be seen by a specialist team. If elbow bending against gravity has not returned by around 3 to 6 months, surgical evaluation is the recommended next step rather than continued watching. ¹ If nobody has raised referral by 3 months, ask about it.

What is the treatment?

From day one: movement

Gentle range-of-motion exercises, taught by a therapist, done daily. The purpose is to keep the joints from stiffening while the nerve recovers. A stiff shoulder limits the final result even if the nerve comes back completely. This is the highest-value thing a family does and it is easy to under-do. ¹

The arm is usually not splinted in a fixed position, because that causes stiffness. Follow the therapist's specific instructions.

Therapy

Referral to early intervention gives access to therapy at no cost to families for a child under 3, and a diagnosed condition such as this qualifies. ⁷ occupational therapy and physical therapy, focused on range of motion, on encouraging use of the affected arm, and later on function. Constraint approaches that limit the good arm are used in some children to encourage use of the affected one. ⁸

Nerve surgery

Considered when recovery stalls, generally between 3 and 9 months of age. Options include removing scar tissue and grafting a nerve across the gap, or nerve transfer, where a working nerve is rerouted to power an important muscle. Timing matters because muscle that has been without a nerve signal for too long stops responding. ¹

Later surgery

Tendon transfers and bone procedures at the shoulder are done in older children to improve position and function where the nerve result was incomplete.

Botulinum toxin

Sometimes used to weaken a muscle that is overpowering its opposite, to allow better positioning while recovery happens.

What is the long-term outlook?

Most babies recover full or near-full function, and most of that recovery happens in the first months. ¹

The pattern of recovery over the first three to six months is the best predictor. A baby who regains elbow bending against gravity early is very likely to do well. A baby who has not by six months has a meaningfully different outlook and belongs in a specialist center.

Where recovery is incomplete, the common long-term picture is limited shoulder movement, difficulty turning the palm upward, and a slightly shorter arm on that side. Many children with residual weakness function very well with adaptations.

Root avulsion injuries do not recover on their own. What can help is nerve transfer surgery, which is why identifying them matters and why it is a specialist decision. ¹

What does daily life look like?

Daily stretches, every day, for months. Families describe this as the hardest habit to keep and the one that mattered most.

Dressing, car seats and carrying all need small adaptations early on.

Two-handed tasks are the practical challenge as a child grows: bikes, instruments, jars, shoelaces. occupational therapy works on these directly.

Sport is usually possible with adaptation. Ask the specialist what to avoid and what is fine, rather than assuming.

For older children, the visible difference and the arm length difference can matter socially. That is worth talking about openly rather than treating as a small thing.

What does care cost over a lifetime?

No agency publishes a lifetime cost for brachial plexus birth injury.

Costs are driven by therapy over years, by nerve surgery in a minority, and by later reconstructive surgery. Where function is largely recovered, long-term cost is low.

This site does not publish a dollar range for this condition, because none is available from a primary source. It is recorded in the site's unsourced log. If a legal case is filed, the relevant number is a life care plan written for your child.

What can you do this week?

1. Ask for the delivery note and the shoulder dystocia note if there was one, including which maneuvers were used, in what order, and the times.
2. Ask for a therapy referral today and get shown the daily range-of-motion exercises.
3. Ask which nerve levels are affected and what movements are being tracked.
4. Ask when the specialist brachial plexus referral happens. If nobody has mentioned it, ask for it.
5. Ask whether the collarbone was X-rayed and whether breathing is normal.
6. Film the arm weekly, in the same position, so recovery is visible over time.
7. Request the complete records with the records request builder.

What should you ask each specialist?

Take these with you. Write the answers down in the moment, because you will not remember them later.

For the pediatrician or neonatologist

• Which nerve levels appear to be affected?
• Is the hand working? Is the diaphragm working?
• Was the collarbone X-rayed?
• Is there a droopy eyelid or a smaller pupil on that side?

For the brachial plexus specialist

• What is the injury type at each level, as best you can tell?
• What movements are you tracking, and what would you expect by 3 months and by 6 months?
• At what point would you consider surgery, and what would it be?
• What happens if we wait too long?

For the therapist

• Show me the exercises and watch me do them.
• How many times a day, and what does too much look like?
• How do we encourage my baby to use that arm?
• What position should the arm be in when sleeping and in the car seat?

You can also build a printable list with the question generator.