All you need to know about Brachial Plexus Injury

by admin-blog-kh | December 31, 2021 9:08 am

What is Brachial Plexus?

The Brachial Plexus is an important member of the Central Nervous System. It’s a network of nerves that start from nerve roots in the neck and beginning of the torso, extending across the shoulder, through the arms, all the way up to the fingers. These nerves carry signals to and from the brain and these parts of the body to control movements of the shoulders, upper and lower arms, wrists and fingers.

The Brachial Plexus consists of five major nerve branches that control specific movements in specific parts of the arms. These are Musculocutaneous nerve, Axillary nerve, Median nerve, Radial nerve and Ulnar nerve. Needless to say, there is one Brachial Plexus on either side of the body (left and right of the head) to manage the respective sides. In addition to carrying signals, the nerves in this network also provide sensation to the skin of the hands.

As one can imagine, an injury to the Brachial Plexus (BP) can severely disrupt the flow of signals between the brain[1] and those parts of the body. This can lead to temporary or permanent disabilities in the affected parts, along with loss of sensation. That is why, it’s important to be aware of Brachial Plexus Injuries (BPI) so that one can take preventive measures to reduce the risk, and emergency treatment in case of injury.

Types of Brachial Plexus Injuries (BPI)

In most cases, a BPI involves the shoulder being pulled or pressed-down in one direction while the head or arm is pulled back in the opposite direction. Depending on how badly the nerves are damaged, BPIs are classified as:

• Avulsion: The root of the nerve is yanked out of the spinal cord[3]. The most severe type
• Rupture: A part of the nerve gets torn
• Neuropraxia: The nerve gets stretched. The least severe type
• Neuroma: Scar tissue forms on the stretched nerve
• Neuritis: This has no clear reason. Also called Parsonage Turner Syndrome

Causes in Infants

• Large size of the baby: A large baby that is being pulled out by the doctors[4] can sustain injuries to the BP
• Breech baby: While most babies come out head first, a breech baby comes out feet first. As the baby is being tugged out, the BP can get injured.
• Shoulder dystocia: When the shoulder of the baby gets stuck under the pubis, pulling the baby’s head can injure the BP in the shoulder area
• Long labour: Complications in a natural childbirth (as opposed to C-section deliveries) can prolong the exit of the baby, causing some injuries to the BP
• Maternal diabetes: A diabetic woman can have a difficult delivery, which increases the risk of BPI in the infant

Consequences of BPI in Infants

• Erb’s palsy: In this, the nerves in the upper BP get damaged, causing numbness, loss of motion near the shoulder, inability to lift an arm, move the elbow or bring objects to the mouth.
• Klumpke’s palsy: In this, nerves in the lower BP get damaged, causing loss of sensation in the wrist and hand, inability to move the hand, wrist or fingers.
• Global Palsy: Here, all five nerves of the BP are damaged, causing inability to move and lack of sensation in – any part of the arm
• Horner Syndrome: An avulsion of one of the nerves leading to the eye, causing drooping eyelids or constricted pupils

In most cases, the condition heals with just physical therapy given to the baby regularly. But in some cases, surgery may be required.

Causes in Children and Adults

• Blunt force trauma: Nasty falls from heights or motor vehicle accidents can cause the shoulder, arm or head to be pushed in different directions causing BPI
• Athletic injuries[5]: Contact sports like football, wrestling, ice hockey, volleyball and cricket can cause collisions between players and hence BPI
• Gunshot wounds: a bullet hitting or grazing the nerves of the BP can cause BPI
• Medical trauma: Surgeries or wrong positioning of the body during a procedure can cause one or more nerves in the BP getting damaged, causing BPI
• Cancer[6]: a tumor that develops in the area served by the BP (primary) or metastasized from another area (secondary) can damage nerves in the BP, causing BPI
• Radiation therapy[7]: Radiation treatments, for the above-mentioned cancers, can also damage some nerves, causing or sustaining BPI.

Symptoms

Depending on the location and extent of the BPI, the person can suffer one or more of the following:

• Numbness or loss of feeling in the wrist, fingers or arm
• Inability to move or control the shoulder, arm, wrist or fingers in the affected side
• An arm that is hanging limply.
• Muscle weakness which make movements difficult
• Severe and sudden pain in the shoulder or arm, which either feels like a burning or stinging sensation
• Loss of sensation such as heat and cold in any part of the shoulder or hand
• Loss of movement or partial paralysis of any part of the arm
• Recurring and prolonged bouts of pain in the affected area

Diagnosis

• Physical examination: The doctor will look for obvious signs such as drooping eyelids, constricted pupils of the eyes, and an arm that hangs limply. Then he/she will tap along the arm in different areas, using different instruments. This helps identify the exact location and extent of the pain, in most cases.
• An X-ray of the neck and shoulder area is taken to check for fractures, dislocations, tissue damage and nerve damage
• MRI / CT scan / CT myelography: These may or may not use a dye to show the injured areas more clearly
• Electromyography (EMG): Needle electrodes are stuck on the affected area, and electrical current is passed. The nerve function and electrical activity (called nerve conduction study) are analyzed to determine the extent of damage to nerves.

Treatment

Depending on the extent of injury, the first line of treatment is always non-surgical. This includes physiotherapy that will restore muscle function, exercises that will strengthen muscles in the affected area and pain-killers to relieve nagging pain or pain episodes. If none of these work, surgery is inevitable. Again, depending on the extent and type of injury, different surgical techniques are used.

• Neurolysis. In this, the scar tissue on the nerves are removed or cleaned out
• Nerve repair: In this, the torn segments of the nerves are attached.
• Nerve graft: In this procedure, nerves taken from other parts of the body are used to replace the damaged nerves in the brachial plexus, in order to provide a bridge for new nerve growths in the area over time.
• Nerve transfer. When the root of an important nerve has been torn from the spinal cord, it may not be possible always to reattach the same. So what the surgeons will do is to take a less important nerve that is still working and attach it to the torn root. In the process, a bypass is created for new nerve growth. This way, muscles served by the nerve start working again.
• Tendon or muscle transfer: In addition to the nerves, muscles or tendons in the area served by the brachial plexus may also get damaged. So similar to nerve transfer, a less important muscle or tendon from another part of your body is removed and transferred to the affected area. The nerves and blood vessels serving the muscle or tendon are also reattached, restoring functionality to the area.

Prevention

Riding or driving safely goes a long way in preventing vehicle accidents. People in contact sports should be watchful and wear protective gear to shield themselves from injuries to any part of the body. A diabetic lady who is planning a baby must constantly watch out for her sugar levels, throughout the term. While helping people who have had a fall or accident, please ensure the head, neck, shoulder and arms are not pulled excessively. All these help reduce the risk of BPI.

Outlook

Not many people are aware of Brachial Plexus Injuries, yet they can be life-altering, causing permanent disabilities in some cases. If you or any of your dear ones have had a recent injury to either arm, shoulder or neck, and are showing any of the above symptoms, rush to a reputed hospital. A neurosurgeon[8] will conduct a series of tests to determine if there is any BPI and if yes, to what extent. Accordingly, he/she will design the best course of treatment for quick recovery and rehabilitation.

---

Reviewed by Dr Suresh S Venkita, Group Medical Director, Kauvery Hospitals

---

Kauvery Hospital is globally known for its multidisciplinary services at all its Centers of Excellence, and for its comprehensive, Avant-Grade technology, especially in diagnostics and remedial care in heart diseases, transplantation, vascular and neurosciences medicine. Located in the heart of Trichy (Tennur, Royal Road and Alexandria Road (Cantonment), Chennai, Hosur, Salem, Tirunelveli and Bengaluru, the hospital also renders adult and pediatric trauma care.

Chennai – 044 4000 6000 • Trichy – Cantonment – 0431 4077777 • Trichy – Heartcity – 0431 4003500 • Trichy – Tennur – 0431 4022555 • Hosur – 04344 272727 • Salem – 0427 2677777 • Tirunelveli – 0462 4006000 • Bengaluru – 080 6801 6801

Source URL: https://www.kauveryhospital.com/blog/neurology/all-you-need-to-know-about-brachial-plexus-injury/

---