Sections

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Diagnostic Considerations

The most common tremor disorders are Parkinson disease and essential tremor. When a patient presents with tremor, the clinician should pay particular attention to the body parts involved, positions/conditions in which the tremor occurs (ie, resting, postural, kinetic, intention), and the frequency of the tremor. It is also critical to look for potential associated signs. The patient should be examined for evidence of parkinsonism (bradykinesia, rigidity, postural instability), dystonia, and other neurologic signs.

An 8-12 Hz action (postural/kinetic) tremor of the upper extremities that is temporarily relieved by drinking alcohol is characteristic of essential tremor, whereas the presence of a pill-rolling rest tremor, bradykinesia, and rigidity is consistent with Parkinson disease and argues against essential tremor.

In patients with parkinsonism, careful attention to the history is necessary to exclude secondary causes such as medications, toxins, or trauma. Medications that block striatal dopamine receptors, such as metoclopramide and neuroleptics, can cause drug-induced parkinsonism. Certain toxins such as MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) and manganese (at high levels of exposure) can also cause parkinsonism.

Consider evaluating patients with parkinsonism for osteoporosis and osteopenia. In a meta-analysis of 23 studies, Tornsey and colleagues found evidence that individuals with Parkinson disease have an increased risk for osteoporosis and osteopenia.^{[35, 36]}A pooled analysis of 2 of the studies, for example, indicated that in patients with Parkinson disease, the odds ratio for developing osteoporosis, when compared with healthy controls, was 2.61, although the increase was lower in men than in women.

Analysis of 14 studies found bone mineral densities in patients with Parkinson disease to be significantly lower at the hip, lumbar spine, and femoral neck, whereas, after an examination of 9 studies, the investigators estimated that bone fracture risk is doubled in Parkinson patients.^{[35, 36]}

Early clinical features that suggest an atypical parkinsonism rather than Parkinson disease include the following^[22]:

Falls at presentation or early in the disease
Poor response to levodopa
Symmetry at disease onset
Rapid disease progression
No tremor
Dysautonomia (eg, urinary incontinence, fecal incontinence, catheterization for urinary retention, persistent erectile failure, prominent symptomatic orthostatic hypotension)

The atypical parkinsonisms are usually associated with little or no tremor, relatively early speech and balance difficulty, and little or no response to dopaminergic medications. Multiple system atrophy (MSA) is relatively symmetric and characterized by parkinsonism, often with some combination of autonomic, corticospinal, and cerebellar dysfunction. Progressive supranuclear palsy (PSP) is relatively symmetric and characterized by parkinsonism with early falls (often in the first year) and a supranuclear gaze palsy in which the patient has difficulty with voluntary down-gaze. Corticobasal ganglionic degeneration (CBD) is typically very asymmetric and characterized by both cortical (difficulty identifying objects, apraxias) and basal ganglionic (usually marked rigidity in an arm) features.

Lewy body disease is characterized by substantial cognitive dysfunction within 1 year of onset of parkinsonism. Hallucinations are common.

Patients with onset of parkinsonism before age 40 years should be tested for Wilson disease, starting with serum ceruloplasmin measurement and ophthalmologic evaluation for Kayser-Fleischer rings.

Differential Diagnoses

Workup

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Media Gallery

Schematic representation of the basal ganglia - thalamocortical motor circuit and its neurotransmitters in the normal state. From Vitek J. Stereotaxic surgery and deep brain stimulation for Parkinson disease and movement disorders. In: Watts RL, Koller WC, eds. Movement Disorders: Neurologic Principles and Practice. New York: McGraw-Hill, 1997:240. Copyright, McGraw-Hill Companies, Inc. Used with permission.
Schematic representation of the basal ganglia - thalamocortical motor circuit and the relative change in neuronal activity in Parkinson disease. From Vitek J. Stereotaxic surgery and deep brain stimulation for Parkinson disease and movement disorders. In: Watts RL, Koller WC, eds. Movement Disorders: Neurologic Principles and Practice. New York: McGraw-Hill, 1997:241. Used with kind permission. Copyright, McGraw-Hill Companies, Inc.
Parkinson disease diary. The patient or caregiver should place 1 check mark in each half-hour time slot to indicate the patient's predominant response during most of that period. The goal of therapeutic management is to minimize off time and on time with troublesome dyskinesia. Copyright Robert Hauser, 1996. Used with permission.
Stages in the development of Parkinson disease (PD)-related pathology (path.). Adapted from Braak H, Ghebremedhin E, Rub U, Bratzke H, Del Tredici K. Stages in the development of Parkinson's disease-related pathology. Cell Tissue Res. 2004 Oct;318(1):121-34.
Schematic diagram of the basal ganglia circuitry. Represented are the following: inhibitory (red arrows) and excitatory (green arrows) projections between the motor cortex, the putamen, the globus pallidus pars externa (GPe) and globus pallidus pars interna (GPi), the subthalamic nucleus (STN), the substantia nigra pars reticulata (SNr) and substantia nigra pars compacta (SNc), and the ventrolateral thalamus (VL). D1 and D2 indicate the direct (regulated by dopamine D1 receptors) and indirect (regulated by dopamine D2 receptors) pathways, respectively.
Sagittal section, 12 mm lateral of the midline, demonstrating the subthalamic nucleus (STN) (lavender). The STN is one of the preferred surgical targets for deep brain stimulation to treat symptoms of advanced Parkinson disease.
The deep brain stimulating lead is equipped with 4 electrode contacts, each of which may be used, alone or in combination, for therapeutic stimulation.
Axial, fast spin-echo inversion recovery magnetic resonance image at the level of the posterior commissure. The typical target for placing a thalamic stimulator is demonstrated (cross-hairs).
Implantation of the deep brain stimulation (DBS) lead.
Insertion of an electrode during deep brain stimulation for Parkinson disease.
Postoperative coronal magnetic resonance image (MRI) demonstrating desired placement of bilateral subthalamic nuclei-deep brain stimulation (STN-DBS) leads.
Radiograph of the skull depicting a deep brain stimulator and leads in a patient with Parkinson disease.
Lewy bodies in the locus coeruleus from a patient with Parkinson disease.
A: Schematic initial progression of Lewy body deposits in the first stages of Parkinson disease (PD), as proposed by Braak and colleagues. B: Localization of the cluster of significant volume reduction in PD compared with health control subjects. The significant cluster located in the medulla oblongata/pons is superimposed as a red blob on the mean normalized anatomic scan of all participants. The axial and sagittal sections are centered on the peak of significance (–1; –36; –49). This image using voxel-based morphometry (VBM), which searched for regional atrophy in idiopathic PD by comparing a group of subjects with the disease and a group of healthy controls. Jubault T, Brambati SM, Degroot C, et al. Regional brain stem atrophy in idiopathic Parkinson's disease detected by anatomical MRI. PLoS ONE. 2009;4(12):e8247.
Gross comparison of the appearance of the substantia nigra between a normal brain and a brain affected by Parkinson disease. Note the well-pigmented substantia nigra in the normal brain specimen on the left. In the brain of a Parkinson disease patient on the right, loss of pigmented substantia nigra due to depopulation of pigmented neurons is observed.
Lewy bodies are intracytoplasmic eosinophilic inclusions, often with halos, that are easily seen in pigmented neurons, as shown in this histologic slide. They contain polymerized alpha-synuclein; therefore, Parkinson disease is a synucleinopathy.

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Author

Robert A Hauser, MD, MBA Professor of Neurology, Molecular Pharmacology and Physiology, Director, USF Parkinson's Disease and Movement Disorders Center, National Parkinson Foundation Center of Excellence, Byrd Institute, Clinical Chair, Signature Interdisciplinary Program in Neuroscience, University of South Florida College of Medicine

Robert A Hauser, MD, MBA is a member of the following medical societies: American Academy of Neurology, American Medical Association, American Society of Neuroimaging, International Parkinson and Movement Disorder Society

Disclosure: Received consulting fee from Cerecor for consulting; Received consulting fee from L&M Healthcare for consulting; Received consulting fee from Cleveland Clinic for consulting; Received consulting fee from Heptares for consulting; Received consulting fee from Gerrson Lehrman Group for consulting; Received consulting fee from Indus for consulting; Received consulting fee from University of Houston for consulting; Received consulting fee from AbbVie for consulting; Received consulting fee from Adama.

Coauthor(s)

Kelly E Lyons, PhD Research Professor of Neurology, Director of Research and Education, Parkinson’s Disease and Movement Disorder Center, University of Kansas Medical Center

Kelly E Lyons, PhD is a member of the following medical societies: American Academy of Neurology, International Parkinson and Movement Disorder Society

Disclosure: Received honoraria from Novartis for speaking and teaching; Received honoraria from Teva Neuroscience for speaking and teaching; Received honoraria from St Jude Medical for board membership.

Theresa A McClain, RN, MSN, ARNP-BC Advanced Registered Nurse Practitioner and Investigator, Parkinson’s Disease and Movement Disorders Center, University of South Florida College of Medicine

Theresa A McClain, RN, MSN, ARNP-BC is a member of the following medical societies: Sigma Theta Tau International

Disclosure: Received consulting fee from Teva for consulting; Received consulting fee from Schering Plough for consulting; Received consulting fee from Biotie for consulting; Received consulting fee from Novartis for consulting.

Rajesh Pahwa, MD Professor of Neurology, Director, Parkinson Disease and Movement Disorder Center, Department of Neurology, University of Kansas Medical Center

Rajesh Pahwa, MD is a member of the following medical societies: American Academy of Neurology, International Parkinson and Movement Disorder Society

Disclosure: Nothing to disclose.

Chief Editor

Selim R Benbadis, MD Professor, Director of Comprehensive Epilepsy Program, Departments of Neurology and Neurosurgery, Tampa General Hospital, University of South Florida Morsani College of Medicine

Selim R Benbadis, MD is a member of the following medical societies: American Academy of Neurology, American Academy of Sleep Medicine, American Clinical Neurophysiology Society, American Epilepsy Society, American Medical Association

Disclosure: Serve(d) as a director, officer, partner, employee, advisor, consultant or trustee for: Bioserenity, Ceribell, Eisai, Jazz, LivaNova, Neurelis, Neuropace, SK life science, Sunovion, Takeda, UCB<br/>Serve(d) as a speaker or a member of a speakers bureau for: Aquestive, Bioserenity, Eisai, Jazz, LivaNova, Neurelis, SK life science, Stratus, Sunovion, UCB<br/>Received research grant from: Cerevel Therapeutics, Ovid Therapeutics, Neuropace, Greenwich Jazz, SK Life Science, Xenon Pharmaceuticals, UCB, Marinus, Neuroelectrics Corporation, Longboard, Janssen, Equilibre Biopharmaceuticals.

Acknowledgements

Ron L Alterman, MD Associate Professor of Neurosurgery, Mount Sinai School of Medicine; Consulting Surgeon, Department of Neurosurgery, Mount Sinai School of Medicine, Elmhurst Hospital, and Walter Reed Army Medical Center

Ron L Alterman, MD is a member of the following medical societies: Alpha Omega Alpha, American Association of Neurological Surgeons, Congress of Neurological Surgeons, Medical Society of the State of New York, and New York County Medical Society

Disclosure: Nothing to disclose.

Heather S Anderson, MD Assistant Professor, Staff Neurologist, Department of Neurology, Alzheimer and Memory Center, University of Kansas Medical Center

Heather S Anderson, MD is a member of the following medical societies: American Academy of Neurology

Disclosure: Nothing to disclose.

Jeff Blackmer, MD, FRCP(C) Associate Professor, Medical Director, Neurospinal Service, Division of Physical Medicine and Rehabilitation, The Rehabilitation Centre, University of Ottawa Faculty of Medicine; Executive Director, Office of Ethics, Canadian Medical Association

Jeff Blackmer, MD, FRCP(C) is a member of the following medical societies: American Paraplegia Society, Canadian Association of Physical Medicine and Rehabilitation, Canadian Medical Association, and Royal College of Physicians and Surgeons of Canada

Disclosure: Nothing to disclose.

Thomas L Carroll, MD Assistant Professor, Department of Otolaryngology-Head and Neck Surgery, Tufts University School of Medicine and Director, The Center for Voice and Swallowing, Tufts Medical Center

Thomas L Carroll, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Otolaryngology-Head and Neck Surgery, American Bronchoesophagological Association, American Laryngological Association, and American Medical Association

Disclosure: Merz aesthetics inc. Consulting fee Speaking and teaching

Richard J Caselli, MD Professor, Department of Neurology, Mayo Medical School, Rochester, MN; Chair, Department of Neurology, Mayo Clinic of Scottsdale

Richard J Caselli, MD is a member of the following medical societies: American Academy of Neurology, American Association of Neuromuscular and Electrodiagnostic Medicine, American Medical Association, American Neurological Association, and Sigma Xi

Disclosure: Nothing to disclose.

Arif I Dalvi, MD Director, Movement Disorders Center, NorthShore University HealthSystem, Clinical Associate Professor of Neurology, University of Chicago Pritzker Medical School

Arif I Dalvi, MD is a member of the following medical societies: European Neurological Society and Movement Disorders Society

Disclosure: Nothing to disclose.

Nestor Galvez-Jimenez, MD, MSc, MHA Chairman, Department of Neurology, Program Director, Movement Disorders, Department of Neurology, Division of Medicine, Cleveland Clinic Florida

Nestor Galvez-Jimenez, MD, MSc, MHA is a member of the following medical societies: American Academy of Neurology, American College of Physicians, and Movement Disorders Society

Disclosure: Nothing to disclose.

Stephen T Gancher, MD Adjunct Associate Professor, Department of Neurology, Oregon Health Sciences University

Stephen T Gancher, MD is a member of the following medical societies: American Academy of Neurology, American Neurological Association, and Movement Disorders Society

Disclosure: Nothing to disclose.

Michael Hoffmann, MBBCh, MD, FCP(SA), FAAN, FAHA Professor of Neurology, University of Central Florida College of Medicine; Director of Cognitive Neurology, Director of Stroke Program, James A Haley Veterans Affairs Hospital

Michael Hoffmann, MBBCh, MD, FCP(SA), FAAN, FAHA is a member of the following medical societies: American Academy of Neurology, American Headache Society, American Heart Association, and American Society of Neuroimaging

Disclosure: Nothing to disclose.

Daniel H Jacobs MD, FAAN, Associate Professor of Neurology, University of Florida College of Medicine; Director for Stroke Services, Orlando Regional Medical Center

Daniel H Jacobs is a member of the following medical societies: American Academy of Neurology, American Society of Neurorehabilitation, and Society for Neuroscience

Disclosure: Teva Pharmaceutical Grant/research funds Consulting; Biogen Idex Grant/research funds Independent contractor; Serono EMD Royalty Speaking and teaching; Pfizer Royalty Speaking and teaching; Berlex Royalty Speaking and teaching

Robert M Kellman, MD Professor and Chair, Department of Otolaryngology and Communication Sciences, State University of New York Upstate Medical University

Robert M Kellman, MD is a member of the following medical societies: American Academy of Facial Plastic and Reconstructive Surgery, American Academy of Otolaryngology-Head and Neck Surgery, American College of Surgeons, American Medical Association, American Neurotology Society, American Rhinologic Society, American Society for Head and Neck Surgery, Medical Society of the State of New York, and Triological Society

Disclosure: GE Healthcare Honoraria Review panel membership; Revent Medical Honoraria Review panel membership

Milton J Klein, DO, MBA Consulting Physiatrist, Heritage Valley Health System-Sewickley Hospital and Ohio Valley General Hospital

Milton J Klein, DO, MBA is a member of the following medical societies: American Academy of Disability Evaluating Physicians, American Academy of Medical Acupuncture, American Academy of Osteopathy, American Academy of Physical Medicine and Rehabilitation, American Medical Association, American Osteopathic Association, American Osteopathic College of Physical Medicine and Rehabilitation, American Pain Society, and Pennsylvania Medical Society

Disclosure: Nothing to disclose.

Kat Kolaski, MD Assistant Professor, Departments of Orthopedic Surgery and Pediatrics, Wake Forest University School of Medicine

Kat Kolaski, MD is a member of the following medical societies: American Academy for Cerebral Palsy and Developmental Medicine and American Academy of Physical Medicine and Rehabilitation

Disclosure: Nothing to disclose.

Jose G Merino, MD Medical Director, Suburban Hospital Stroke Program

Jose G Merino, MD is a member of the following medical societies: American Heart Association and American Stroke Association

Disclosure: Nothing to disclose.

Arlen D Meyers, MD, MBA Professor, Department of Otolaryngology-Head and Neck Surgery, University of Colorado School of Medicine

Arlen D Meyers, MD, MBA is a member of the following medical societies: American Academy of Facial Plastic and Reconstructive Surgery, American Academy of Otolaryngology-Head and Neck Surgery, and American Head and Neck Society

Disclosure: Covidien Corp Consulting fee Consulting; US Tobacco Corporation Unrestricted gift Unknown; Axis Three Corporation Ownership interest Consulting; Omni Biosciences Ownership interest Consulting; Sentegra Ownership interest Board membership; Syndicom Ownership interest Consulting; Oxlo Consulting; Medvoy Ownership interest Management position; Cerescan Imaging Honoraria Consulting; GYRUS ACMI Honoraria Consulting

Lorraine Ramig, PhD Professor, Department of Speech Language Hearing Sciences, University of Colorado at Boulder; Senior Scientist, National Center for Voice and Speech (NCVS); Adjunct Professor, Department of Biobehavior, Columbia University Teacher's College

Disclosure: Nothing to disclose.

Alan D Schmetzer, MD Professor Emeritus, Interim Chairman, Vice-Chair for Education, Associate Residency Training Director in General Psychiatry, Fellowship Training Director in Addiction Psychiatry, Department of Psychiatry, Indiana University School of Medicine; Addiction Psychiatrist, Midtown Mental Health Cener at Wishard Health Services

Alan D Schmetzer, MD is a member of the following medical societies: American Academy of Addiction Psychiatry, American Academy of Clinical Psychiatrists, American Academy of Psychiatry and the Law, American College of Physician Executives, American Medical Association, American Neuropsychiatric Association, American Psychiatric Association, and Association for Convulsive Therapy

Disclosure: Eli Lilly & Co. Grant/research funds Other

Roy Sucholeiki, MD Director, Comprehensive Seizure and Epilepsy Program, The Neurosciences Institute at Central DuPage Hospital

Roy Sucholeiki, MD is a member of the following medical societies: American Academy of Neurology, American Epilepsy Society, and American Neuropsychiatric Association

Disclosure: Nothing to disclose.

Margaret M Swanberg, DO Assistant Professor of Neurology, Uniformed Services University; Chief of Neurobehavior Service, Walter Reed Army Medical Center; Assistant Chief, Department of Neurology, Walter Reed Army Medical Center

Margaret M Swanberg, DO is a member of the following medical societies: American Academy of Neurology and American Neuropsychiatric Association

Disclosure: Nothing to disclose.

Michele Tagliati, MD Associate Professor, Department of Neurology, Mount Sinai School of Medicine; Division Chief of Movement Disorders, Mount Sinai Medical Center

Michele Tagliati, MD is a member of the following medical societies: American Academy of Neurology, American Medical Association, and Movement Disorders Society

Disclosure: Nothing to disclose.

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Medscape Salary Employment

B Viswanatha, MBBS, MS, DLO Professor of Otolaryngology (ENT), Chief of ENT III Unit, Sri Venkateshwara ENT Institute, Victoria Hospital, Bangalore Medical College and Research Institute; PG and UG Examiner, Manipal University, India and Annamalai University, India

B Viswanatha, MBBS, MS, DLO is a member of the following medical societies: Association of Otolaryngologists of India, Indian Medical Association, and Indian Society of Otology

Disclosure: Nothing to disclose.