Parsonage-Turner Syndrome

Original Editors - Jesse Demeester

Top Contributors - Jesse Demeester, Lennert De Henau, Evan Thomas, Kim Jackson, Claudia Karina, Admin, Selena Horner, WikiSysop, Wendy Walker and Adam Vallely Farrell   </div>

Definition/Description

Parsonage–Turner syndrome (PTS) is the term used to describe a neuritis involving the brachial plexus. It may present with symptoms of an isolated peripheral nerve lesion, although the pathology is thought to lie more proximally. PTS generally involves one upper limb, mostly the axillary nerve, the upper trunk of the brachial plexus, the suprascapular nerve and the long thoracic nerve are affected.

Clinically Relevant Anatomy

The brachial plexus is a network of nerve fibers. The fibers are running from the spine and are formed by the ventral rami of the lower four cervical (C5-C8) and first thoracic roots (T1). Afterwards it proceeds through the neck, the axilla and into the arm. The brachial plexus innervates the upper arm (brachium), forearm (antebrachium) and hand.6

Epidemiology /Etiology

The incidence of neuralgic amyotrophy is approximately 2 to 3 per 100,000 persons per year. The
distribution of disease shows a predominance of men over women (approximately 3:2), with the highest incidence occurring between the third and seventh decades.3 Parsonage – Turner Syndrome occurs with an overall reported incidence of 1.64 cases per 100.000 people. There does not appear to be a prevalence for hand dominance nor is there a general trend towards development of the condition more on the left versus the right.4 The etiology of the syndrome is unclear. It is reported in various clinical situations including postoperatively, postinfectious, posttraumatic and postvaccination. So the precise cause remains unknown.5

Characteristics/Clinical Presentation

Initially a sudden constant, severe shoulder girdle pain develops, This pain may extend to the trapezius ridge, upper arm, forearm, and hand. The pain is not positional and usually worse at night and may be associated with awakenings from sleep. The pain is often described as a severe ache or throbbing radiating from the shoulder distally down the arm or proximally into the neck. The duration of pain is almost always self-limiting, lasting 1 to 2 weeks but on rare occasions can persist for longer periods of time.4,6
Other symptoms are:
- Sensory deficits (not in all the patients)
- Muscle weakness
- Muscle-atrophy (within a month)

Scapular winging may be seen when there is involvement of the scapulothoracic nerve innervating the serratus anterior muscle. The weakness may be limited to muscles innervated by a single peripheral nerve or any combination of peripheral nerves or the brachial plexus.
On EMG study a widespread denervation is seen of the affected muscles.
MRI may show a nonspecific inflammatory response in the brachial plexus in case of PTS.

Differential Diagnosis

In the beginning the pain is situated around the shoulder girdle. It can look like numerous shoulder problems. Like11:
- Rotator cuff tears
- Adhesive capsulitis
- Calcific tendonitis
- Arthritis
Further away muscle weakness kicks in. Also this can look like numerous shoulder problems. Like11:
- Discogenis nerve root compression
- Tumors of the spinal cord
- Thoracic outlet syndrome
- Cervical artery dissection
Differential diagnosis on MRI findings includes 12,13:
- Disuse atrophy of shoulder girdle muscules
- Quadralateral space syndrome
- Trauma
- Other entrapment syndromes around shoulder

Diagnostic Procedures

The characteristic pattern of pain followed by profound weakness are generally the clues to the diagnosis of Parsonage– Turner syndrome1,2,3,4 with confirmation being sought by electromyography. This pain is often described as a severe ache or throbbing radiating from the shoulder distally down the arm or proximally into the neck Because of the often atypical distribution, EMG- studies need to be extremely detail- oriented in the systematic approach to testing specific muscles of the upper limb. Testing of muscles that are not routinely examined during EMG studies should be interrogated by needle EMG even when they appear to be clinically asymptomatic. Because Parsonage – Turner Syndrome is an axonal disorder commonly affecting proximal muscles of the upper limb, the motor and sensory nerve conduction velocities and distal latencies routinely tested on the distal upper limb are usually normal. 5

Outcome Measures

add links to outcome measures here (also see Outcome Measures Database)

Examination

add text here related to physical examination and assessment

Medical Management

add text here

Physical Therapy Management

add text here

Key Research

add links and reviews of high quality evidence here (case studies should be added on new pages using the case study template)

Resources

add appropriate resources here

Clinical Bottom Line

add text here

Recent Related Research (from Pubmed)

see tutorial on Adding PubMed Feed

References

see adding references tutorial.