What is Parsonage Turner Syndrome?
Parsonage Turner Syndrome is unexpected pain build up in the shoulder. The syndrome unilaterally affects the shoulder and onset are sudden. The pain syndrome becomes severe and intensity of the pain become increasing within a very quick interval.
Thus acute pain converted to the long-lasting pain that extends from days to a week or more with other progressive problems. The shoulder girdle musculature and proximal upper limb muscles are mainly exaggerated in Parsonage-Turner Syndrome. Alternatively, this Syndrome is also known as neuralgic amyotrophy or brachial neuritis. [1,3]
Parsonage Turner Syndrome History
In 1897, the similar clinical presentations as Parsonage-Turner Syndrome were mentioned in an extensive study of a medical literature. Parsonage and Turner first described of idiopathic brachial plexopathy in 1949. The condition becomes popular according to the name of the describers of the syndrome. 
Parsonage-Turner Syndrome symptoms describes as follows:
- The onset of pain is sudden
- Initially pain intensity is constant
- Severity of the pain is high and affects in unilateral shoulder girdle
- Gradual pain syndrome extends to the trapezius ridge, upper arm, forearm, and hand
- Parsonage-Turner Syndrome is not associated with postural pain syndrome
- High nocturnal pain intensity
- Sleep disturbance
- Pain symptom of Parsonage-Turner Syndrome is self-limited
- Parsonage-Turner Syndrome pain extends 1 to 2 weeks, though in rare cases it may extend longer
- Progressive weakness occurs after a few days of onset of the pain syndrome
- Sensory deficits
- The involve muscle strength become weak
- Scapular winging formation due to the involvement of the scapulothoracic nerve innervating the serratus anterior muscle. [3,4]
Several associated biological condition involve in Parsonage-Turner Syndrome. These are:
- Bacterial , viral or parasitic infections, such as smallpox and swine flu
- Anesthetics used in surgery
- Certain hereditary conditions
- Ehlers-Danlos Syndrome in which problems is associated in connective tissues
- Rheumatic disease
- Vaccinations like tetanus toxoid and DPT (Diptheria, pertussis, and tetanus) vaccine
- Intense exercise
- Dislocation of shoulder girdle
- Traumatic injury
- Certain arteritis like temporal arteritis, polyarteritis nodosa
- Systemic lupus erythematosus
- Other miscellaneous conditions are radiation, lumber puncture, dye administration for radiologic analysis, pregnancy and childbirth etc. 
Etiologic associations are involved in the development of the Parsonage-Turner Syndrome. It has been found that only one condition may not be involved as a developmental factor, but multifactoral conditions which are related to both genetic and environmental mainly causes Parsonage-Turner Syndrome. Individual with genetic susceptibility exposed in favorable environmental triggers has affected with Parsonage-Turner Syndrome.
Parsonage-Turner syndrome is also known as idiopathic neuralgic amyotrophy, due to the involvement of certain nerves, such as suprascapular nerve, axillary nerve, and subscapular nerve. The association of these nerves may be alone or combined mode. The involvement of suprascapular nerve affects mainly supraspinatus and infraspinatus muscles and gradually involves deltoid muscles, which is innervated by axillary nerve.
Parsonage-Turner Syndrome is mainly unilateral, but clinician also reported bilateral involvement. [3,4,5]
The initial diagnosis is based on the symptomatic analysis. The depending upon the sign and symptoms different imaging diagnostic tools are used for confirmatory tests. The following tests may recommend for diagnosis, including
Nerve conduction studies
This test analyzes the capacity of possible involves nerve to convey a message to the brain.
This test evaluates the physical condition of the nerve and muscle present at the site of the pain. In this test, a very thin needle electrode is inserted into the muscle of the affected area. The needle select the electrical activity, which is visible on the connected monitor .
Magnetic Resonance Imaging or MRI scan
This is an imaging test that utilizes potent magnets and radio waves to generate images of the body. Contrast MRI can also perform to get information of the involves blood vessels.
In this test x-ray particles passed through the body and the obtain images is recorded on a computer or film. [3,4,6]
The treatment of Parsonage-Turner Syndrome is based on following approaches:
- Non-steroidal anti-inflammatory drugs (NSAIDs), Opiates and neuroleptics are the different available medications to control the pain syndrome at the initial stage. The selection of the drug is based on pain severity and also patient related factors.
- Oral steroids, like prednisone or other corticosteroids and immune-modulating therapies, are also prescribed for limited cases.
- Acupuncture and transcutaneous electrical nerve stimulation (TENS)
- TENS are applied along with medication to get a better result.
- Antiviral drugs also prescribed for patients, who suffers from viral infection
- Physiotherapy is also recommended for certain cases
- Specific types of exercise are also recommended for strengthening the muscle, but it depends on upon underlying cause, such as grade of muscle denervation, the level of weakness, and the extent of distorted biomechanics and to the pre-morbid serviceable degree of activity for a particular patient.
- Surgical intervention is recommended when all other options are ineffective. [1,2,3]
The prognosis of Parsonage-Turner Syndrome is not fixed for all, some individuals completely recover after a single episode of pain and no more complain about functionality or strength related issues in their shoulder. Maximum affected patient recover within 2 to 3 years. But recently clinical study report also mentioned that some patients condition get worse with increasing time due to associated complications. The patient affected with bilateral Parsonage-Turner Syndrome have a poor prognosis. [4,7,8]
- Parsonage Turner Syndrome; National Organization for Rare Disorders; Retrieve from: https://rarediseases.org/rare-diseases/parsonage-turner-syndrome/
- Allen IM. The neurological complication of serum treatment. Lancet. 1931;2:1128–1131. doi: 10.1016/S0140-6736(00)78218-3.
- Joseph H. Feinberg, Jeffrey Radecki, Parsonage-Turner Syndrome; HSS J. 2010 Sep; 6(2): 199–205; Published online 2010 Jul 30. doi: 10.1007/s11420-010-9176-x
- Parsonage Turner syndrome; Genetic and Rare diseases Information Center; Retrieve from: https://rarediseases.info.nih.gov/diseases/4228/parsonage-turner-syndrome
- Gaskin CM, Helms CA. Parsonage-Turner syndrome: MR imaging findings and clinical information of 27 patients. Radiology. 2006;240 (2): 501-7. doi:10.1148/radiol.2402050405
- Dr. Tim Luijkx and A.Prof Frank Gaillard◉ et al.; Parsonage-Turner syndrome; Retrieve from: https://radiopaedia.org/articles/parsonage-turner-syndrome-2
- Parsonage Turner syndrome. NORD. May 2014; Retrieve from: http://www.rarediseases.org/rare-disease-information/rare-diseases/byID/726/viewAbstract.
- Nigel L Ashworth. Brachial Neuritis. Medscape Reference. May 8, 2016; http://emedicine.medscape.com/article/315811-overview.