Erb’s palsy, also called Erb-Duchenne palsy, is a nerve disorder that occurs as a result of an injury during birth. The disorder is a form of brachial plexus palsy, impacting the nerves near the neck (brachial plexus) and causing weakness and loss of motion in the arm. The condition got it’s name from one of the first doctors to describe it in detail in 1874, Wilhelm Erb.
Erb’s palsy affects about one or two out of every 1,000 children born. Many patients experience an improved range of motion naturally over time and through physical therapy.
Erb’s Palsy Causes and Risk Factors
Erb’s palsy is caused by a stretching of the brachial plexus nerves during a baby’s birth. This type of birth injury happens when the head and shoulder moving in opposite directions, and may occur in a number of ways, including:
- As the baby’s shoulders travel through the birth canal, the head and neck are pulled towards the side.
- The baby’s shoulders are stretched during a head-first deliver.
- During a breech (feet-first) delivery, increased pressure is put on the raised arms.
There are a few factors that increase a baby’s risk of developing Erb’s palsy. Larger babies have a greater risk of injury during birth that may lead to the nerve disorder. Similarly, breech delivery, prolonged labor, and difficulty delivering the baby’s shoulders can put pressure on the brachial plexus and cause damage.
Where possible, avoiding a difficult delivery can help reduce the chances of a birth injury In high-risk cases, a cesarean delivery can also reduce a child’s risk.
Types of Erb’s Palsy
There are four different types of nerve injury that cause Erb’s palsy. These are defined by the injury to the nerve itself. Injuries can occur on their own or simultaneously, and impact the severity of the disorder and the method of treatment used.
- Neurapraxia: This is the most common nerve injury, occurring when the nerve is stretched but not torn. Stretched nerves will often heal by themselves over the course of a few months.
- Neuroma: In this case, stretching of the nerve causes scar tissue to form as the nerve fibers heal. The scar tissue makes it difficult for complete recovery.
- Rupture: A ruptured nerve happens when the nerve is torn. Surgery will likely be necessary as it will not heal on its own.
- Avulsion: The most severe injury, avulsion happens when the nerve is torn from the spinal cord. A graft from another nerve may be required to restore movement in the arm.
Symptoms and Diagnosis of Erb’s Palsy
Symptoms of Erb’s palsy are immediate and often obvious. The most common symptoms include:
- No movement in one of the baby’s arms (upper or lower)
- No movement in one of the baby’s hands
- One arm limp, bent, and held against the body
- Loss of feeling in the arm
- Partial or total paralysis of the affected arm
- Weakness in the arm, leading to a decreased grip
If a child shows signs of Erb’s palsy, a pediatrician will perform a physical examination and imaging tests. The doctor will test the nerve and muscle fibers using an electromyogram (EMG) test, as well as using an MRI or CT scan to look at the damage to the nerves and make a diagnosis.
Treatments for Erb’s Palsy
There are no definitive treatments for Erb’s palsy, and symptoms usually resolve over time.
Many doctors recommend rest and immobilization of the affected arm for about one week after diagnosis. Doctors will then usually prescribe a regimen of physical therapy exercises to improve the child’s range of motion and prevent the joints from becoming stiff.
If the nerves are torn through rupture or avulsion, the baby may need surgery to treat the disorder and help stimulate movement. Surgery will either consist of a nerve graft (splicing a donor nerve) or nerve transfer (using a nerve from another muscle).
Erb’s Palsy Prognosis and Statistics
In almost 80% of cases, Erb’s palsy resolves itself, and strength and motion are regained in the first year of the child’s life. If the disorder is diagnosed within four weeks after birth, this rate is even higher.
Patients with Erb’s palsy may experience one arm (the affected arm) growing at a slower pace than the other, leading it to be smaller. In some cases, the child may have lifelong problems with the affected arm, which can result in self-esteem issues and difficulty in performing tasks. Many parents find it useful to consult a child psychologist if their child is affected by Erb’s palsy.
If you suspect your child has Erb’s palsy, or notice any symptoms of movement issues in an arm, talk to a doctor. The earlier treatment begins, the better chance of a full recovery.