2019

Plexopathies: Complex & Perplexing

Ryan D. Jacobson MD Assistant Professor of Rush University Medical Center, Chicago IL 2019 Financial Disclosure • I have no relevant disclosures 2019 Warning Videotaping or taking pictures of the slides associated with this presentation is prohibited. The information on the slides is copyrighted and cannot be used without permission and author attribution. Agenda

• Goal: to provide a case-based discussion of common and uncommon issues in the neuromuscular evaluation of brachial plexopathies with focus on key clinical pearls

• The approach will be more clinical and decision-making based rather than anatomic or electrodiagnostic. Agenda

• Brachial Plexus Anatomy & Trauma

• Brachial Neuritis / Parsonage-Turner Syndrome – Pathophysiology & Anatomic Specifics – Imaging – Prognosis – Rare Causes & Associations

• Malignancy: Infiltration vs. Radiation

• We will not delve into MR vs. ultrasound evaluation of the plexus much. • Part 1: Brachial Plexus Anatomy & Trauma Case 1: Caught in the Crossfire • 27-year-old man presents for evaluation of right hand and weakness • 4 months prior, he was caught in the crossfire at a gas station, and shot in the right chest. Bullet exited right armpit. • Immediately thereafter, the right arm was “frozen.” Case 1, continued

• Over the subsequent months, his right arm strength has improved markedly. • However, he continues to experience severe weakness of the right hand. • He has numbness over the right 4th and 5th digits, and medial hand. • Referred for EMG to evaluate localization of lesion, for prognostication Case 1, examination

• On focused examination, there is wasting of the right hand intrinsics and the anterior forearm. • There is weakness of the deep finger flexors, interossei, abductor pollicis brevis, flexor pollicis longus, and wrist flexors. • Proximally, the arm is strong, and pronation, wrist extension, and finger extension seem strong. • Pinprick is diminished over the 5th digit and medial 4th digit.

Where would you localize this patient’s symptoms? • C8 root?

• Lower trunk of the brachial plexus?

• Medial cord of the brachial plexus?

• Lateral cord of the brachial plexus?

42 patients seen following World War 2 with penetrating brachial plexus .

13 upper trunk injuries – all recovered antigravity strength

21 injuries of posterior cord – majority recovered antigravity strength

25 injuries of C8/ T1 / medial cord. – any recovery rare

• Part 2: Brachial Neuritis / Parsonage-Turner Syndrome Inflammatory: Neuralgic Amyotrophy, Brachial Plexitis, Parsonage Turner Syndrome

• Tend to have unilateral pain, followed by weakness and wasting • Tends to affect upper trunk, tends to be very patchy • Special predilection for , suprascapular nerve, sometimes distal involvement (AIN) • Pathology microvasculitic • Prognosis for continued recovery good • Steroids: may help pain, little evidence for help in motor recovery • MRI may be abnormal but mostly a clinical diagnosis

What’s in the literature? Annual incidence of 1.64 per 100,000 population

Precipitating Causes

• Early case series: – Spillane 1946: 26 of 46 cases were already hospitalized at the time of presentation – Parsonage and Turner: some precipitating factor or illness in 98 of 136. 66 were already hospitalized

Prognosis and Natural History

• Early reports from Parsonage and Turner (1957)

Treatment of Parsonage-Turner?

• Tsairis, 1972: 10 patients given oral prednisone, 5 given IM ACTH, 15 with cortisone injections into the shoulder. Some pain relief.

• Van Alfen 2006: 41 of 246 patients treated with (oral). 25% found it helpful, median time to decrease in pain was 5 days compared to 20 days.

• Van Eijk 2009: 50 patients treated with oral prednisone for a month and compared to historical controls. See next slide.

27 28 Case 2: Inpatient with Shoulder Pain

• 69-year-old man with multiple myeloma presented for evaluation of right shoulder pain and weakness • History of multiple myeloma 9 months prior when he presented with back pain and compression fracture. X-rays revealed numerous lucencies. • SPEP/IFIX abnormal, and bone marrow biopsy consistent with myeloma • Treated with Bortezomib, Lenalidumide, Dexamethasone Case 2, continued

• Admitted 3/2017 for autologous stem cell transplant with melphalan conditioning “PBSCT” Case 2, continued • 3/13, 3/14/17: Melphalan infusion • 3/15/17: PBSCT • 3/20/17: developed severe right shoulder pain and received • 3/21/17: notes difficulty in lifting arm above his head • 3/24/17: neurology consultation, unable to abduct shoulder • 3/27/17: discharged from hospital EMG, 4/7/2016

Case 2, continued

• 4/18/17: follows up in neurology clinic.

• Examination: atrophy of right infraspinatus. Full strength other than: – R Deltoid 2/5 strength – R Infraspinatus 3/5 strength – No obvious scapular winging Diagnosis?

Brachial Neuritis

Why? • Several autoimmune complications, including neuromuscular complications, possible after allogeneic SCT

• Case 1: autologous SCT, melphalan. Bilateral upper extremity weakness and areflexia 14 days later.

• Case 2: autologous SCT, melphalan. Bilateral upper extremity weakness and “within 14 days.”

• Case 3: autologous SCT, melphalan. Unilateral hand pain and C5/C6 myotome weakness 14 days later. Case 3: Swim in the Ganges gone wrong

• 29-year-old man is referred for evaluation of left shoulder pain and weakness • Recently admitted for acute liver failure • Traveling in India from mid-December through mid-March 2017 • In mid-March, he went swimming in the Ganges River with his roommate to celebrate the end of the trip Case 3, continued

• Late March 2017: developed fever, chills, nausea, and abdominal pain. Developed unusual “greasy” bowel movements • 4/8/2017: transferred to academic center Case 3, continued

• 4/9/2017: begins to note unusual, vague, dull left shoulder pain

• 4/10/17: noted to have numbness, over left L deltoid muscle. PT notes difficulty with shoulder abduction and external rotation. X-ray normal. Case 3, continued

• 4/21/2017: continues to note severe L shoulder pain and mild shoulder weakness. 5/8/17

• Neurology visit: pain has improved to 4/10 severity, but still with severe left shoulder pain Hepatitis E

• ssRNA virus • Spread by fecal-oral route, blood. Often spread through drinking water. • Most common cause of acute infectious hepatitis in the world. • Only 2-5% of infected patients are symptomatic. • Endemic in Asia, Africa

• About 30-40 cases in the literature • None in the US as far as I can tell • 26 of the 30 with bilateral involvement

Case 3, update

• Prescribed 50 mg prednisone

• Physical therapy

• Weakness gradually improved Case 4: Complex Patient with a Floppy Thumb

• 49 year old man presents for evaluation of left thumb weakness • History of lupus nephritis, renal transplant • About 5 weeks ago, fell about 8 feet and bruised his ribs, spent two days in bed • While in bed, noted worsening left shoulder, elbow, and hand pain Case 4, continued

• While recovering, noted that his left thumb was weak and could not be bent correctly. • Also developed unusually severe pain over the pad of the left thumb. • Over time, the pain has gradually improved but severe thumb flexion weakness persists. Case 4, examination

General: old fistula site in left volar mid forearm

Neurologic Exam Motor: full strength other than no movement of left thumb flexion. Thumb opposition, abduction strong. Pronation strong, finger flexion strong. Sensory: pinprick sensation normal throughout

Predilection for the AIN

• First seen by Parsonage & Turner, further defined by Kiloh and Nevin (1952)

ANTERIOR INTEROSSEOUS NERVE PALSY A review of 16 cases

M. K. SOOD and F. D. BURKE

From the Pulvertaft Hand Centre, Derbyshire Royal Infirmary, Derby, UK

• Reviewed 16 cases of AIN palsy • 4 traumatic, 12 spontaneous • Part 3: Malignancy, Infiltration vs. Radiation Case 5

• 63 year old woman presents for evaluation of right arm weakness and numbness • 2014: diagnosed with R breast cancer, treated with surgery, radiation, • 2016-2017: presented with recurrent disease affecting R chest skin, R chest wall. Treated with chemotherapy • 2017: underwent right carpal tunnel release Case 5

• She now presents to the neurology clinic for worsening R arm symptoms. • Despite CTS surgery, she has worsening numbness of the lateral hand and lateral forearm • Also notices mild weakness of the R arm Case 5

• Exam: 4-/5 weakness in R biceps Trace weakness R deltoid, triceps, infraspinatus. Hyporeflexic throughout. Diminished pinprick sensation over lateral hand and forearm.

MR Brachial Plexus Neoplastic

• Most common in lung/breast cancer • More likely to affect the lower trunk • More likely to be painful • EMG: dysfunction in distribution of • Imaging: may show enhancement, nodularity, presence of tumor Radiation Plexopathy

• Most common following treatment of breast cancer • Tends to develop insidiously over months – mean of 10 months after radiation completion • More likely to affect upper trunk • Less likely to be painful • EMG: dysfunction in distribution of injury, and myokymia • Imaging: may show hyperintensity, enhancement of plexus

• THANK YOU

• Please see the printed handout for references.