Parsonage-Turner Syndrome: Causes, Phases, and Prognosis
Medically reviewed by Nicholas R. Metrus, MDMedically reviewed by Nicholas R. Metrus, MD
Parsonage-Turner syndrome (PTS) is a neurological disorder that causes severe pain in the shoulder and arm, and can cause lasting damage to nearby muscles, nerves, and ligaments. PTS, also known as brachial neuritis, commonly occurs within the brachial plexus—a nerve network under the arm that bridges the cervical nerves of the neck along the clavicle and extending into the arm.
PTS may also refer to other forms of peripheral nerve disorders elsewhere in the body. It is believed to be caused by an immune disorder, possibly secondary to a common viral infection, but the exact causes are still unclear. The overall lasting effect of PTS varies widely between individuals.
This article looks at the symptoms and causes of PTS, including how the condition is treated.
Symptoms of Parsonage-Turner Syndrome
Parsonage-Turner syndrome (PTS) is a neurological disorder that causes severe pain in the shoulder and arm, typically on one side of the body.
This pain can coincide with weakening and loss of muscle mass in the affected areas over a period of weeks. PTS affects 1.64 in 100,000 people per year, though the incidence of PTS may be underdiagnosed and somewhat higher.
The symptoms associated with PTS can be divided into acute, chronic, and recovery phases.
Acute Phase
The initial sign of PTS is usually a sudden pain in one or both shoulders, often affecting the corresponding side of the neck or arm, though one-sided pain is far more common.
This initial pain may be sharp, burning, or a dull, throbbing ache. It may also present as a change in sensation in the area. From the initial pain level, the pain may increase quickly in some people or it may gradually ramp up.
Chronic Phase
After the acute phase, which may last anywhere from hours to a few weeks, the pain will eventually decrease. It may disappear completely or remain at a lesser intensity in some cases.
Even after the acute symptoms of PTS have diminished, nerve damage may preclude some muscle movement and use. Lifting, bending, and other activities may cause pain to the nerves of the affected muscle areas. Besides pain, the lasting damage to muscles and nerves ranges from barely noticeable weakness to complete loss of movement.
In the affected areas, this weakness can cause:
Decreased sensation or numbness
Pins-and-needles sensation or burning
Increased sensitivity to touch
Structurally, atrophy may cause changes in the position and function of:
Shoulders
Arms
Wrists
Hands
Recovery Phase
During or after the chronic phase, a secondary complication can occur with atrophy called subluxation, a dislocation of the shoulder joint.
When certain tendons in the shoulder area change position, some mobility of the shoulder joint can be lost due to chronic pain and inflammation affecting the connective tissue. Damage and loss of movement to the shoulder joint capsule may reflect an inflammatory condition known as adhesive capsulitis.
Other lasting symptoms include circulatory issues. The skin of the hands and arms may swell (edema) and become discolored with blotches of red, purple, or spotting. Hair and nail growth may speed up. There may also be excessive sweating or poor response in arms, hands, or fingers to temperature changes in the environment.
Other forms of PTS affecting different parts of the body may lead to pain and dysfunction localized to specific nerves, including:
Lumbosacral plexus: Lower back pain radiating into the legs
Phrenic nerve: Weakening of the diaphragm can cause shortness of breath
Recurrent laryngeal nerve: Hoarseness of the voice due to weakness or partial paralysis of the vocal cords
Facial or cranial nerves: Rarely affected with unique impairments
Causes of Parsonage-Turner Syndrome
The cause of the onset of PTS is not fully understood, but there are many potential environmental factors that may induce it, including:
Surgery on the brachial plexus
Childbirth
Unusually strenuous exercise
Physical trauma
Recent vaccination
Bacterial, viral, or parasitic infection
Anesthesia
Rheumatologic disease or tissue inflammation
Autoimmune disorders
Hereditary Neuralgic Amyotrophy
PTS is sometimes also known as idiopathic neuralgic amyotrophy, and this name indicates a non-genetic or unknown cause. Hereditary neuralgic amyotrophy (HNA) is a hereditary form of PTS.
It is estimated that 85% of the time, HNA is caused by a mutation in the SEPT9 gene, which produces a protein important to cell division.
Loss of SEPT9 protein function also predicts higher cancer risks. Mutation of SEPT9 is expressed dominantly, so symptoms of HNA may occur even when just one copy of the gene is present. Targeted genetic testing is available for the SEPT9 gene.
Family indicators of the hereditary form of PTS are:
Short height
Excess folds on neck and arm skin
Cleft palate
Split uvula (the small, teardrop-shaped tissue hanging at the back of your throat)
Partially webbed fingers or toes
Eyes positioned close together
Narrowly opening eyelids
Narrow mouth
Facial asymmetry
Diagnosis
PTS can be diagnosed by a physician such as a neurologist by using patient history and reported symptoms, and specialized testing including a brachial plexus MRI and electromyogram (EMG) or nerve conduction study (NCS) to identify the source and intensity of symptoms.
Testing
Tests may include electromyography (EMG) to measure muscle and nerve health. If nerves are not conducting electrical impulses normally when stimulated by electrodes, a neuromuscular specialist can identify what specific nerves are affected by a PTS injury.
An MRI of the brachial plexus in the arm can be used to identify causes of shoulder pain, find the muscles affected by atrophy, and identify where damage affecting larger nerves has occurred.
In some cases, an X-ray or CT scan can be used to rule out other causes of pain or loss of movement that may affect the shoulder, besides PTS, and what may be responsible.
Treatment of Parsonage-Turner Syndrome
The purposes of PTS treatments are to alleviate symptoms that affect quality of life and recovery and, if necessary, restore normal function of the affected arm and shoulder.
During the intense, acute phase of PTS, people may need to take medications to reduce pain. Commonly, the prescription use of NSAIDs or opioid pain medications may alleviate the discomfort.
Physical therapy and therapeutic pain relief, such as hot-cold treatments, can also be used to reduce pain and to maintain muscle mass and range of motion.
Use of a TENS (Transcutaneous Electrical Nerve Stimulation) unit, a machine that applies electrical impulses to muscle through the surface of the skin, may be an additional useful therapeutic option, reducing pain in some people.
For chronic nerve pain that is extreme and unresponsive to other treatments, surgery (including nerve grafts and tendon transfers) may offer solutions that reduce pain and restore movement.
Replacement of damaged tendons can help recover loss of movement in the shoulder, particularly two or more years after the initial onset of PTS if nerves and muscles are damaged and have not responded to other forms of treatment.
Intravenous immune globulin (IVIG) therapy may be an effective treatment, but further research is needed.
Is There a Cure for Parsonage-Turner Syndrome?
There isn't a specific cure for PTS. Treatment is generally focused on managing symptoms that are present. In some cases, however, the condition may resolve on its own.
Coping With Parsonage-Turner Syndrome
Residual pain and immobility may be an issue in repetitive everyday tasks and manual labor. While most people regain most, if not all, of their strength within two to three years, management of pain during the acute and chronic phases of PTS is important.
Advanced symptoms, such as partial paralysis and intractable pain, may warrant physical therapy and surgery. These solutions can help prevent complete loss of the functions of nerves and muscles during the early phases or help to restore them in the recovery phase.
Prognosis
It is difficult to predict how PTS will affect an individual. After the first PTS attack, there is a 25% chance of a recurring attack, and about 10-20% of people with PTS may have persisting pain or problems with shoulder movement.
Summary
Parsonage-Turner syndrome is a nerve disorder that causes severe pain in the arm and shoulder. This may lead to muscle wasting and weakness in the affected areas. This condition can be diagnosed by a healthcare provider.
The outcomes of PTS vary, and it is important to discuss a plan with your healthcare team to manage pain relief and physical therapies. With more advanced symptoms, like partial paralysis or muscle atrophy, surgery may be an important option when considering your lifestyle needs. It is hard to predict how long the acute and chronic phases may linger, so work closely with your healthcare providers to ensure the condition is optimally managed.
Read the original article on Verywell Health.
