Erb’s palsy is a condition involving total or partial paralysis of the arm and hand due to nerve damage. It occurs when there’s an injury to the brachial plexus, specifically the upper brachial plexus at birth. The injury can stretch, rupture or avulse the roots of the plexus from the spinal cord.
The most common cause of Erb’s palsy is excessive pulling or stretching of an infant’s head and shoulders during a vaginal birth. For example, if an infant’s head and neck are pulled to the side at the same time as the shoulders pass through the birth canal; this can cause Erb’s palsy.
Risk factors of Erb’s palsy include:
- Large infant size or high birth weight
- Maternal diabetes
- Small or abnormal maternal pelvis shape
- Using extraction tools like forceps during delivery
- Second stage of labor lasting over an hour
- Excessive maternal weight gain
- Breech delivery
- Other forms of improper pediatric health care
Different Types of Erb’s Palsy
- Neuropraxia: This is most common and least severe type of Erb’s palsy. It occurs when the nerves in the brachial plexus are overstretched during birth but the nerves do not actually tear.
- Neuroma: A more serious type of Erb’s palsy results when the nerve injury is classified as a neuroma. With this type of injury, the nerves are still not torn but they get stretched so severely that scar tissue forms as they heal. The scar tissue creates pressure and pinching within the nerves.
- Rupture: When the nerves within the brachial plexus are stretched so much that the nerve tissue actually tears apart, the injury is classified as a rupture.
- Avulsion: The most serious cases of Erb’s palsy occur when the damage to the nerves is classified as an avulsion. This type of nerve injury occurs when the nerve fibers are actually torn away and detached from the spinal cord or surrounding structure.
- Baby does not move one arm or arm appears weaker than the other
- Arm hangs by the side and rotated inward
- Decreased grip strength in hand of the affected side
- Numbness in arm
- Impaired circulatory, muscular and nervous development
- Partial or total paralysis of the arm
A thorough history and physical examination with focus on neurologic examination are used to confirm diagnosis.
- History– Aims to gather information about pregnancy complicated either by gestational diabetes or maternal obesity, fetal macrosomia, prolonged second stage labour, shoulder dystocia, use of assistive techniques-forceps to aid delivery.
- Physical examination– most often shows decreased or absent movement of the affected arm.
- Neurologic examination– assesses muscle power, sensation, reflexes- more reflex is absent on the affected arm.
Daily physical therapy is the main treatment method for Erb’s palsy.
- MFR (Myofascial Release): Myofascial Release (MFR) is a safe and very effective hands-on technique that involves applying gentle sustained pressure into the Myofascial connective tissue restrictions to eliminate pain and restore motion.
- ROM Exercise: Your physical therapist will assess the motion of your involved leg compared with expected normal motion and the motion of the hip on your uninvolved leg. Then he will improve the condition of the restricted motion.
- Strengthening: Because of the restricted movements, associate muscles become too much weak. It’s very important to improve their strength and your physiotherapist will help you to regain it with strengthening exercises.
- Stretching: Your physiotherapist will stretch your spastic muscles to regain their normal functions.
- IRR: It helps to warm up your shoulder with arm and surrounding muscles and reduce the pain.
- Electrical Stimulation: It is used to improve arm strength and has some evidence to show it can help with pain reduction.
- UST: Providing thermal or non-thermal treatment of the injured tissue at a frequency range of 0.75 to 3 MHz (depending on the depth of the soft tissue to be treated)
- Laser: Laser is used in an acute or severe condition for deep penetration and relieving the pain.
Many children with brachial plexus injuries will continue to have some weakness in the shoulder, arm, or hand. There may be other surgical procedures that can be performed at a later date that might improve function. As your child grows, your doctor will discuss the various treatment options and make a specific recommendation based on your child’s individual situation.