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Orthostatic tremor: Delayed onset following head trauma
888
CLINICAL
NOTES
Orthostatic Tremor: Delayed Onset Following Head Trauma Scott S. Sunitate,
MD, Joseph R. Meerschaert,
MD
ABSTRACT. Sanitate SS, Meerschaert JR. Orthostatic tremor: delayed onset following head trauma. Arch Phys Med
Rehahil 1993;74:886-9. Orthostatic tremor is a 14 to 16Hz (range 7 to 36Hz) tremor of uncertain etiology elicited within seconds of an
l
isometric contraction. It is described as a shaking, cramping of the lower extremities upon standing and is relieved with movement or sitting. Typically patients are unable to stand in place for long periods of time secondary to instability and fatigue. A 73-year-old woman with orthostatic tremor following a history of head trauma is presented. Recognition of the characteristic history and electromyographic findings may lead to appropriate treatment for this annoying and sometimes incapacitating disorder. 0 1993 by the American Congress of_ Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitkion KEY WORDS: Head trauma; Orthostatic tremor
Orthostatic tremor was first described in 1984 by Heilman,’ who presented three patients in whom tremors developed in the trunk and lower extremities upon standing. The tremor abated with movement or sitting and was not present at rest. Two patients responded to clonazepam. Approximately 52 cases have been reported since Heilman’s report, with characteristic electromyographic findings and additional recommendations for pharmacologic treatment. The term “orthostatic tremor” is misleading because the tremor may be elicited with strong isometric contractions regardless of position and space. WalkerZ suggested a more appropriate title, “isometric tremor.” Other authors’ have described this entity as the “shaky-legs syndrome” even though tremor has been noted in the upper extremities as well as the trunk and head. Variability in tremor frequency and synchronicity have also been described. A frequency range of 7 to 32Hz has been reported, and the most common frequency is in the 14 to 16Hz interval.2 More often synchronization between firing of antagonist and agonist muscle groups has been reported, although asynchrony and both patterns in an individual have been described.2-9,1’ CASE REPORT A 72-year-old right handed woman with a past medical history
significant for Hashimotos thyroiditis, spinal stenosis, osteoarthritis and a 20-year history of hypertension presented with a 12-year history of progressive “cramping, shaking legs” when standing that disappeared with sitting, ambulation and/or relief of weight bearing on the symptomatic extremity. She recalled that approximately 2 weeks before her symptoms appeared, she sustained a blow to the back of the skull after falling. She denied loss of consciousness or any physical/psychological abnormalities postFrom William Beaumont Hospital, Royal Oak, MI. Submitted for publication October 9, 1992. Accepted in revised form January 14, 1993. No commercial party having a direct or indirect interest in the subject matter of this article has or will confer a benefit upon the authors or upon any organization with which the authon are associated. Reprint requests to Scott S. Sanitate, MD, Carolina Rehabilitation Associates, 2501 Atrium Drive, Raleigh, NC 27607. 0 1993 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation C@O3-9993/93/7408-0010$3.00/0 Arch Phys Med Rehabil Vd 74, August 1993
trauma. In the past 2 years her symptoms have interfered with her ability to stand in line while shopping. She denied paresthesias, bowel or bladder dysfunction, and/or improvement with alcohol or P-blockers. She was unsuccessfully treated in 1985. For 7 years she has had multiple workups, which have included thyroid function tests, complete blood counts, blood chemistries, a muscle biopsy and head computed tomography, all ofwhich were normal. Electromyography (EMG) at another institution revealed a 4Hz tremor with standing and no evidence of neuropathy or myopathy. Medications used without benefit or discontinued because of side effects included Tegretol,” 800mg/d, Quinamm,b primidone, SOOmg/d, and IUonopin,C 2mg/d. Current medications include Tenormint 50mg/d, Maxzide: and Synthroid,f. 1Smg/d. She denied ethanol abuse or a beneficial effect with ethanol or an aggravation of the tremor with caffeine ingestion. There was no family history of tremor or movement disorder. The physical examination found no mental status abnormalities. Trthostatic blood pressure changes, cog wheeling, ataxia on finger to nose/heel to shin testing, motor weakness, sensory or reflex abnormalities. No tremor was noted with outstretched arms and hands or in her voice. Her tremor was reproducible with standing and weight bearing in both the upper and lower extremities. She could alter her “cramping” by shifting weight from one extremity to the other. She described symptoms of tightness and the perception of “rock hard” muscles in the legs. This was evident on palpation of the muscles of the weight-bearing extremity. An electromyogram revealed moderate paraspinal membrane irritability in the lumbosacral region with no anterior rami changes with the patient at rest. Nerve conduction velocities and distal latencies were within normal limits. There was no tremor noted in the supine position. When the patient stood, a 7 channel EMG demonstrated an asynchronous 14 to 15Hz tremor in the gastrocnemius and tibialis anterior, hamstrings and quadriceps, and paraspinals. No tremor was appreciated in the upper extremities until the patient was asked to lean and bear weight on an upper extremity (fig). Further testing included visual evoked responses (VER), brainstem auditory evoked responses (BAER), EEG, and repeat thyroid function tests, all of which were within normal limits. Abnormalities were noted on brain magnetic resonance imaging (MRI), single photon emission computerized tomography (SPECT scan), and lower extremity somatosensory evoked potentials (SSEPTs). The brain MRI demonstrated ischemic demyelination in the periventricular region and subcortical white matter. Ischemic changes were also noted in the right pons and the right cerebellar hemi-
ORTHOSTATIC TREMOR, Sanitate
887
quadricepe
.,,,,
.,,
.._.“.. ..:.,.....,..: _.: Biceps
Triceps
EMG tracings from the above listed muscles revealed no tremor at rest. (A) Upon standing, lower extremities demonstrated a 14 to 15Hz tremor that was asynchronous between antagonist muscles. (B) Simultaneous recordings in the upper, lower, and paraspinals revealed tremor in the paraspinals and lower extremities but not in the uppers. (C) With weight bearing on the upper extremity a synchronous 14 to 15Hz tremor was elicited.
sphere. SPECT scan revealed decreased perfusion in the right putamen, thalamus and frontal lobe. Left lower extremity SSEPs were delayed, consistent with the later findings of an L5 radiculopathy and history of spinal stenosis. Unsuccessful pharmacologic intervention included Klonopin, 3mg/d, Sinemet: 25/250 three times a day, Lioresal,” 1Omg three times a day Xanax,’ lmg three times a day, clorazepate, 7Smg three times a day, Depakote) 750mg/d, phenobarbital 120mg/d. Sedative side effects were the most common complication of these drugs, none of which provided significant relief of her tremor. DISCUSSION
Orthostatic tremor has recently found its way into the tremor classification as a task-specific tremor along with writing tremor and vocal tremor. Its more common frequency of 14 to 16Hz tends to distinguish it from other tremors. The spectrum of tremor classification is illustrated in the table. The etiology of orthostatic tremor has remained uncertain although Gabellini and Martinelli6 described orthostatic tremor in a patient with hydrocephalus secondary to aqueductal stenosis and an additional case with relapsing poly-neuropathy that resolved with ventriculoperitoneal shunting and prednisone, respectively. 0da9 and Cristea” noted that orthostatic tremor can be a manifestation of Parkinson’s disease and its treatment leads to improvement of the tremor. In addition, Wee” studied a family with essential tremor and noted that some members of the family had both orthostatic tremor and essential tremor. He and
others7,‘2*‘7postulated that orthostatic tremor may be a variant of essential tremor. Our patient recalled that within weeks after accidentally striking the back of her head her symptoms began and thereafter have slowly progressed. Posttraumatic tremor after a mild head injury without loss of consciousness has been
Tremor Classification I. Tremor at rest Parkinson’s pill rolling 2. Postural tremor Physiologic tremor Exaggerated physiologic tremor Essential tremor Tremor with basal ganglion disease Parkinson’s disease Dystonia Wilson’s disease Cerebellar postural tremor Mild cerebellar postural tremor Tremor with neuropathy 3. Kinetic tremor Cerebellar intention tremor Task-specific tremor Primary writing tremor Vocal tremor Orthostatic tremor* 4. Hysterical tremor
4-5Hz (range, 3-7Hz)
8- 12Hz hands, or as slow as 6.SHz elsewhere 4-9Hz
2.54Hz IOHz ?A-4Hz 3-5HZ
13-IhHz (range. 7-36Hz)
* Data from Hallett.* Arch Phys Med Rehabil VoI74, August 1993
888
ORTHOSTATIC TREMOR, Sanitate
reported.‘3 These authors also reported seven cases of Unlike essential tremor, orthostatic tremor has not been responsive to P-blockers and rarely to ethanol.3 It does not tremor similar to essential tremor as a rare complication respond to benzodiazepines other than ones mentioned predeveloping within weeks following head trauma. Reference knowledge of rehabilitative apto Heilman’s original article is made in one of the cases in viously. Unfortunately, which truncal tremor would develop after 30 seconds of proaches for this disorder are lacking. standing. Although inconclusive, the possibility of a temIt is uncertain whether the approximately 52 cases reporal relationship between our patient’s head trauma and ported reflect a true prevalence of this disorder or whether her tremor cannot be excluded. the total number of cases remains unrecognized or underreThompson’ has postulated that orthostatic tremor is gen- ported. Our patient presented with a unique history in that erated by spontaneous oscillation in the central structures head trauma occurred 2 weeks prior to the development of responsible for organizing motor programs in standing. her symptoms. The tremor frequency of 4Hz reported 5 Other authors* have hypothesized that impaired regulation years earlier increased to the present 14 to 15Hz and corof muscle spindle feedback or interaction between periphrelated with her progressive complaints. Recognizing this eral and central structure@ may be the cause. For the most disorder by its peculiar history and characteristic electropart, the vast majority of reported cases of orthostatic diagnostic abnormalities may expedite definitive pharmacotremor have had negative diagnostic evaluations including logic treatment. EEG.3 In the reported cases females outnumber males by a 34: 18 ratio and there tends to be a middle-age-to-senior References onset 1-7,9-‘2,‘4-17 Its course is slowly progressive and a family 1. Heilman KM. Orthostatic tremor. Arch Neurol 1984;41:880-1. history of essential tremor was present in less than 50% of 2. Walker FO, McCormick GM, Hunt VP. isometric features of orthostatic tremor: an electromyographic analysis. Muscle Nerve reported cases.“’ ‘x1*This case presentation is typical al1990; 13:9 18-22. though it does have some peculiarities in that the MRI re3. Veilleux M, Sharbrough FW, Kelly JJ, Westmoreland BF, Daube JR. vealed diffuse ischemic demyelinization and small infarcts Shaky-Legs syndrome. J Clin Neurophys 1987;4:304-5. in the right pons and cerebellum. In addition, SPECT scan 4. Uncini A, Onofrj M, Basciani M, Cutarella R, Gambi D. Orthostatic demonstrated decreased perfusion in the right putamen tremor: report of two cases and an electrophysiologicat study. Acta and frontal regions. Neurol Stand 1989;79: 119-22. 5. Thompson PD. Roghwell JC, Day BL, et al. The physiology of orthoThe electromyographic characteristics have been delinstatic tremor. Arch Neurol 1986;43:584-7. eated as follows*: ( 1) Tremor appears after a latent period of 6. Gabellini AS, Martinelli P, Gulli MR, Ambrosetto G, Ciucci G, Luusually seconds but sometimes minutes. (2) After incepgaresi E. Orthostatic tremor: essential and symptomatic cases. Acta tion, the tremor increases or has a crescendo pattern. (3) Neurol Stand 1990;8 1: 113-7. Although the arms are involved to a lesser degree in 60% of 7 Fitzgerald PM, Jankovic J. Orthostatic tremor: an association with patients, the tremor primarily affects the legs. (4) The essential tremor. Mov Disord 199 1;6:60-4. 8. Hallett M. Classification and treatment of tremor. JAMA tremor frequency typically is 14 to 16Hz but other frequen1991;266:1115-1117. cies have been identified (7 to 32Hz). (5) The EMG bursts 9. Oda K, Fukushima N, Kakigi R, Shibasake H. A case. of orthostatic associated within the tremor are discreet, large amplitude, tremor in parkinsonism 1989;29:924-6. and easily recorded. (6) The tremor does not reset with elec10. Cristea RL, Goren H. Orthostatic tremor. Arch Neurol 199 1;48: 1119. trical stimulation (a feature of essential tremor). This was 11. Wee AS, Subramony SH, Currier RD. “Orthostatic tremor” in familnot examined in our patient. (7) The tremor invariably imial-essential tremor. Neurology 1986;36: 124 1-5. 12. Koller WC, Glatt S, Biary N, Rubino FA. Essential tremor variants: proves with action such as walking. (8) The tremor appears effect of treatment. Clin Neuropharmacol 1987;10:342-50. with isometric activation of muscle. 13. Bipory N. Cleeves L, Findley L, Koller W. Post-traumatic tremor. We observed synchronous contractions between antagoNeurology 1989;39:103-106. nists in the upper extremities and asynchronous contrac14. van der Zwan A, A Verwey JC, Van Gijn J. Relief of orthostatic tions in the lower extremities during isometric contraction tremor by primidone. Neurology 1988;38: 1332. while weight bearing. The paraspinal muscles demon15. Cabrera-Valdivia F, Jimenez-Jimenez F. Orthostatic tremor: successful treatment with phenobarbital. Clin Neuropharmacol 199 1;14:438strated a similar tremor frequency with standing. They were 41. absent when the patient was sitting or prone (fig). The 16. Papa SM, Gershanik OS. Orthostatic tremor: an essential tremor varitremor could be elicited on a tilt table in the lower extremiant? Movement Disord 1988;3:97-108. ties at 45” with the lower extremities weight bearing and 17. Cleeves L, Cowan J, Findley LJ. Orthostatic tremor: diagnostic entity disappeared when in the horizontal position. or variant of essential tremor? J Neurol Neurosurg Psychiatry The most successful treatment has used clonazepam, 1 to 1989:52:131-l. 18. Gates P, Thyagarajan D. Orthostatic tremor: a cause of postural insta4mg/d.‘-’ Unfortunately, the sedative side effects may bility in the elderly. Med J Aust 1990: I52:373. outweigh its benefit. Primidone, 500mg to 625mg/d,4.‘2*‘4 phenobarbital, 100 to 150mg/d,6*15,16valproic acid, and clorazepate3 have also provided symptomatic relief. CombiSuppliers arbamazepine; Geigy Pharmaceuticals, Wimblehurst Road, Hornation regimens of clonazepam and primidone’ as well as ham. West Sussex RH 12 4AB, England. clonazepam and valproic acid3 have also been successfully uinine sulphate; Merrill Dow Pharmaceuticals Incorporated, subsidused. In some instances the initial successful responses to q of The Dow Chemical Company, Cincinnati, OH 45242-9553. clonazepam or primidone were less effective over time and lonazepam; Roche Laboratories, division ofHoffman-La Roche Incorrequired either supplementation or substitution. L2~14~17.18 #orated. Nutley, NJ 10965. Arch Phyo Med Rehabil Vol74, August 1993
ORTHOSTATIC d. atenolol: Stuart Pharmaceuticals Limited. Stuart House, 50 Alderley Road, Wilmslow, Cheshire SD9 IRE, England. e. triamterene; Lederle Laboratories. division of American Cynamid Company, Pearl River, NY 10965. f. levothyroxine sodium; Flint Laboratories of Canada. division of Travenal Canada, Incorporated. 6695 Airport Road, Mississauga, Ontario L4V I TL, Canada. g. carbidopa; Merck Sharp and Dohm (Australia). Pty Limited, PO Box 79. Granville NSW 2 142. Australia.
TREMOR,
889
Sanitate
h. baclofen; Geigy Pharmaceuticals, division of Ciba-Geigy Corporation. Ardsley, NY 10502. i. alprazolam; The Upjon Company. 7000 Portage Road. Kalamazoo. MI 49001. j. valpormide; Abbott Laboratories, Pharmaceutical North Chicago. IL 60064.
Products Division.
j. valpormide; Abbott Laboratories, Pharmaceutical North Chicago, IL 60064.
Products Division,
Arch Phys Med Rehabil Vol74, August 1993
CLINICAL
NOTES
Orthostatic Tremor: Delayed Onset Following Head Trauma Scott S. Sunitate,
MD, Joseph R. Meerschaert,
MD
ABSTRACT. Sanitate SS, Meerschaert JR. Orthostatic tremor: delayed onset following head trauma. Arch Phys Med
Rehahil 1993;74:886-9. Orthostatic tremor is a 14 to 16Hz (range 7 to 36Hz) tremor of uncertain etiology elicited within seconds of an
l
isometric contraction. It is described as a shaking, cramping of the lower extremities upon standing and is relieved with movement or sitting. Typically patients are unable to stand in place for long periods of time secondary to instability and fatigue. A 73-year-old woman with orthostatic tremor following a history of head trauma is presented. Recognition of the characteristic history and electromyographic findings may lead to appropriate treatment for this annoying and sometimes incapacitating disorder. 0 1993 by the American Congress of_ Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitkion KEY WORDS: Head trauma; Orthostatic tremor
Orthostatic tremor was first described in 1984 by Heilman,’ who presented three patients in whom tremors developed in the trunk and lower extremities upon standing. The tremor abated with movement or sitting and was not present at rest. Two patients responded to clonazepam. Approximately 52 cases have been reported since Heilman’s report, with characteristic electromyographic findings and additional recommendations for pharmacologic treatment. The term “orthostatic tremor” is misleading because the tremor may be elicited with strong isometric contractions regardless of position and space. WalkerZ suggested a more appropriate title, “isometric tremor.” Other authors’ have described this entity as the “shaky-legs syndrome” even though tremor has been noted in the upper extremities as well as the trunk and head. Variability in tremor frequency and synchronicity have also been described. A frequency range of 7 to 32Hz has been reported, and the most common frequency is in the 14 to 16Hz interval.2 More often synchronization between firing of antagonist and agonist muscle groups has been reported, although asynchrony and both patterns in an individual have been described.2-9,1’ CASE REPORT A 72-year-old right handed woman with a past medical history
significant for Hashimotos thyroiditis, spinal stenosis, osteoarthritis and a 20-year history of hypertension presented with a 12-year history of progressive “cramping, shaking legs” when standing that disappeared with sitting, ambulation and/or relief of weight bearing on the symptomatic extremity. She recalled that approximately 2 weeks before her symptoms appeared, she sustained a blow to the back of the skull after falling. She denied loss of consciousness or any physical/psychological abnormalities postFrom William Beaumont Hospital, Royal Oak, MI. Submitted for publication October 9, 1992. Accepted in revised form January 14, 1993. No commercial party having a direct or indirect interest in the subject matter of this article has or will confer a benefit upon the authors or upon any organization with which the authon are associated. Reprint requests to Scott S. Sanitate, MD, Carolina Rehabilitation Associates, 2501 Atrium Drive, Raleigh, NC 27607. 0 1993 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation C@O3-9993/93/7408-0010$3.00/0 Arch Phys Med Rehabil Vd 74, August 1993
trauma. In the past 2 years her symptoms have interfered with her ability to stand in line while shopping. She denied paresthesias, bowel or bladder dysfunction, and/or improvement with alcohol or P-blockers. She was unsuccessfully treated in 1985. For 7 years she has had multiple workups, which have included thyroid function tests, complete blood counts, blood chemistries, a muscle biopsy and head computed tomography, all ofwhich were normal. Electromyography (EMG) at another institution revealed a 4Hz tremor with standing and no evidence of neuropathy or myopathy. Medications used without benefit or discontinued because of side effects included Tegretol,” 800mg/d, Quinamm,b primidone, SOOmg/d, and IUonopin,C 2mg/d. Current medications include Tenormint 50mg/d, Maxzide: and Synthroid,f. 1Smg/d. She denied ethanol abuse or a beneficial effect with ethanol or an aggravation of the tremor with caffeine ingestion. There was no family history of tremor or movement disorder. The physical examination found no mental status abnormalities. Trthostatic blood pressure changes, cog wheeling, ataxia on finger to nose/heel to shin testing, motor weakness, sensory or reflex abnormalities. No tremor was noted with outstretched arms and hands or in her voice. Her tremor was reproducible with standing and weight bearing in both the upper and lower extremities. She could alter her “cramping” by shifting weight from one extremity to the other. She described symptoms of tightness and the perception of “rock hard” muscles in the legs. This was evident on palpation of the muscles of the weight-bearing extremity. An electromyogram revealed moderate paraspinal membrane irritability in the lumbosacral region with no anterior rami changes with the patient at rest. Nerve conduction velocities and distal latencies were within normal limits. There was no tremor noted in the supine position. When the patient stood, a 7 channel EMG demonstrated an asynchronous 14 to 15Hz tremor in the gastrocnemius and tibialis anterior, hamstrings and quadriceps, and paraspinals. No tremor was appreciated in the upper extremities until the patient was asked to lean and bear weight on an upper extremity (fig). Further testing included visual evoked responses (VER), brainstem auditory evoked responses (BAER), EEG, and repeat thyroid function tests, all of which were within normal limits. Abnormalities were noted on brain magnetic resonance imaging (MRI), single photon emission computerized tomography (SPECT scan), and lower extremity somatosensory evoked potentials (SSEPTs). The brain MRI demonstrated ischemic demyelination in the periventricular region and subcortical white matter. Ischemic changes were also noted in the right pons and the right cerebellar hemi-
ORTHOSTATIC TREMOR, Sanitate
887
quadricepe
.,,,,
.,,
.._.“.. ..:.,.....,..: _.: Biceps
Triceps
EMG tracings from the above listed muscles revealed no tremor at rest. (A) Upon standing, lower extremities demonstrated a 14 to 15Hz tremor that was asynchronous between antagonist muscles. (B) Simultaneous recordings in the upper, lower, and paraspinals revealed tremor in the paraspinals and lower extremities but not in the uppers. (C) With weight bearing on the upper extremity a synchronous 14 to 15Hz tremor was elicited.
sphere. SPECT scan revealed decreased perfusion in the right putamen, thalamus and frontal lobe. Left lower extremity SSEPs were delayed, consistent with the later findings of an L5 radiculopathy and history of spinal stenosis. Unsuccessful pharmacologic intervention included Klonopin, 3mg/d, Sinemet: 25/250 three times a day, Lioresal,” 1Omg three times a day Xanax,’ lmg three times a day, clorazepate, 7Smg three times a day, Depakote) 750mg/d, phenobarbital 120mg/d. Sedative side effects were the most common complication of these drugs, none of which provided significant relief of her tremor. DISCUSSION
Orthostatic tremor has recently found its way into the tremor classification as a task-specific tremor along with writing tremor and vocal tremor. Its more common frequency of 14 to 16Hz tends to distinguish it from other tremors. The spectrum of tremor classification is illustrated in the table. The etiology of orthostatic tremor has remained uncertain although Gabellini and Martinelli6 described orthostatic tremor in a patient with hydrocephalus secondary to aqueductal stenosis and an additional case with relapsing poly-neuropathy that resolved with ventriculoperitoneal shunting and prednisone, respectively. 0da9 and Cristea” noted that orthostatic tremor can be a manifestation of Parkinson’s disease and its treatment leads to improvement of the tremor. In addition, Wee” studied a family with essential tremor and noted that some members of the family had both orthostatic tremor and essential tremor. He and
others7,‘2*‘7postulated that orthostatic tremor may be a variant of essential tremor. Our patient recalled that within weeks after accidentally striking the back of her head her symptoms began and thereafter have slowly progressed. Posttraumatic tremor after a mild head injury without loss of consciousness has been
Tremor Classification I. Tremor at rest Parkinson’s pill rolling 2. Postural tremor Physiologic tremor Exaggerated physiologic tremor Essential tremor Tremor with basal ganglion disease Parkinson’s disease Dystonia Wilson’s disease Cerebellar postural tremor Mild cerebellar postural tremor Tremor with neuropathy 3. Kinetic tremor Cerebellar intention tremor Task-specific tremor Primary writing tremor Vocal tremor Orthostatic tremor* 4. Hysterical tremor
4-5Hz (range, 3-7Hz)
8- 12Hz hands, or as slow as 6.SHz elsewhere 4-9Hz
2.54Hz IOHz ?A-4Hz 3-5HZ
13-IhHz (range. 7-36Hz)
* Data from Hallett.* Arch Phys Med Rehabil VoI74, August 1993
888
ORTHOSTATIC TREMOR, Sanitate
reported.‘3 These authors also reported seven cases of Unlike essential tremor, orthostatic tremor has not been responsive to P-blockers and rarely to ethanol.3 It does not tremor similar to essential tremor as a rare complication respond to benzodiazepines other than ones mentioned predeveloping within weeks following head trauma. Reference knowledge of rehabilitative apto Heilman’s original article is made in one of the cases in viously. Unfortunately, which truncal tremor would develop after 30 seconds of proaches for this disorder are lacking. standing. Although inconclusive, the possibility of a temIt is uncertain whether the approximately 52 cases reporal relationship between our patient’s head trauma and ported reflect a true prevalence of this disorder or whether her tremor cannot be excluded. the total number of cases remains unrecognized or underreThompson’ has postulated that orthostatic tremor is gen- ported. Our patient presented with a unique history in that erated by spontaneous oscillation in the central structures head trauma occurred 2 weeks prior to the development of responsible for organizing motor programs in standing. her symptoms. The tremor frequency of 4Hz reported 5 Other authors* have hypothesized that impaired regulation years earlier increased to the present 14 to 15Hz and corof muscle spindle feedback or interaction between periphrelated with her progressive complaints. Recognizing this eral and central structure@ may be the cause. For the most disorder by its peculiar history and characteristic electropart, the vast majority of reported cases of orthostatic diagnostic abnormalities may expedite definitive pharmacotremor have had negative diagnostic evaluations including logic treatment. EEG.3 In the reported cases females outnumber males by a 34: 18 ratio and there tends to be a middle-age-to-senior References onset 1-7,9-‘2,‘4-17 Its course is slowly progressive and a family 1. Heilman KM. Orthostatic tremor. Arch Neurol 1984;41:880-1. history of essential tremor was present in less than 50% of 2. Walker FO, McCormick GM, Hunt VP. isometric features of orthostatic tremor: an electromyographic analysis. Muscle Nerve reported cases.“’ ‘x1*This case presentation is typical al1990; 13:9 18-22. though it does have some peculiarities in that the MRI re3. Veilleux M, Sharbrough FW, Kelly JJ, Westmoreland BF, Daube JR. vealed diffuse ischemic demyelinization and small infarcts Shaky-Legs syndrome. J Clin Neurophys 1987;4:304-5. in the right pons and cerebellum. In addition, SPECT scan 4. Uncini A, Onofrj M, Basciani M, Cutarella R, Gambi D. Orthostatic demonstrated decreased perfusion in the right putamen tremor: report of two cases and an electrophysiologicat study. Acta and frontal regions. Neurol Stand 1989;79: 119-22. 5. Thompson PD. Roghwell JC, Day BL, et al. The physiology of orthoThe electromyographic characteristics have been delinstatic tremor. Arch Neurol 1986;43:584-7. eated as follows*: ( 1) Tremor appears after a latent period of 6. Gabellini AS, Martinelli P, Gulli MR, Ambrosetto G, Ciucci G, Luusually seconds but sometimes minutes. (2) After incepgaresi E. Orthostatic tremor: essential and symptomatic cases. Acta tion, the tremor increases or has a crescendo pattern. (3) Neurol Stand 1990;8 1: 113-7. Although the arms are involved to a lesser degree in 60% of 7 Fitzgerald PM, Jankovic J. Orthostatic tremor: an association with patients, the tremor primarily affects the legs. (4) The essential tremor. Mov Disord 199 1;6:60-4. 8. Hallett M. Classification and treatment of tremor. JAMA tremor frequency typically is 14 to 16Hz but other frequen1991;266:1115-1117. cies have been identified (7 to 32Hz). (5) The EMG bursts 9. Oda K, Fukushima N, Kakigi R, Shibasake H. A case. of orthostatic associated within the tremor are discreet, large amplitude, tremor in parkinsonism 1989;29:924-6. and easily recorded. (6) The tremor does not reset with elec10. Cristea RL, Goren H. Orthostatic tremor. Arch Neurol 199 1;48: 1119. trical stimulation (a feature of essential tremor). This was 11. Wee AS, Subramony SH, Currier RD. “Orthostatic tremor” in familnot examined in our patient. (7) The tremor invariably imial-essential tremor. Neurology 1986;36: 124 1-5. 12. Koller WC, Glatt S, Biary N, Rubino FA. Essential tremor variants: proves with action such as walking. (8) The tremor appears effect of treatment. Clin Neuropharmacol 1987;10:342-50. with isometric activation of muscle. 13. Bipory N. Cleeves L, Findley L, Koller W. Post-traumatic tremor. We observed synchronous contractions between antagoNeurology 1989;39:103-106. nists in the upper extremities and asynchronous contrac14. van der Zwan A, A Verwey JC, Van Gijn J. Relief of orthostatic tions in the lower extremities during isometric contraction tremor by primidone. Neurology 1988;38: 1332. while weight bearing. The paraspinal muscles demon15. Cabrera-Valdivia F, Jimenez-Jimenez F. Orthostatic tremor: successful treatment with phenobarbital. Clin Neuropharmacol 199 1;14:438strated a similar tremor frequency with standing. They were 41. absent when the patient was sitting or prone (fig). The 16. Papa SM, Gershanik OS. Orthostatic tremor: an essential tremor varitremor could be elicited on a tilt table in the lower extremiant? Movement Disord 1988;3:97-108. ties at 45” with the lower extremities weight bearing and 17. Cleeves L, Cowan J, Findley LJ. Orthostatic tremor: diagnostic entity disappeared when in the horizontal position. or variant of essential tremor? J Neurol Neurosurg Psychiatry The most successful treatment has used clonazepam, 1 to 1989:52:131-l. 18. Gates P, Thyagarajan D. Orthostatic tremor: a cause of postural insta4mg/d.‘-’ Unfortunately, the sedative side effects may bility in the elderly. Med J Aust 1990: I52:373. outweigh its benefit. Primidone, 500mg to 625mg/d,4.‘2*‘4 phenobarbital, 100 to 150mg/d,6*15,16valproic acid, and clorazepate3 have also provided symptomatic relief. CombiSuppliers arbamazepine; Geigy Pharmaceuticals, Wimblehurst Road, Hornation regimens of clonazepam and primidone’ as well as ham. West Sussex RH 12 4AB, England. clonazepam and valproic acid3 have also been successfully uinine sulphate; Merrill Dow Pharmaceuticals Incorporated, subsidused. In some instances the initial successful responses to q of The Dow Chemical Company, Cincinnati, OH 45242-9553. clonazepam or primidone were less effective over time and lonazepam; Roche Laboratories, division ofHoffman-La Roche Incorrequired either supplementation or substitution. L2~14~17.18 #orated. Nutley, NJ 10965. Arch Phyo Med Rehabil Vol74, August 1993
ORTHOSTATIC d. atenolol: Stuart Pharmaceuticals Limited. Stuart House, 50 Alderley Road, Wilmslow, Cheshire SD9 IRE, England. e. triamterene; Lederle Laboratories. division of American Cynamid Company, Pearl River, NY 10965. f. levothyroxine sodium; Flint Laboratories of Canada. division of Travenal Canada, Incorporated. 6695 Airport Road, Mississauga, Ontario L4V I TL, Canada. g. carbidopa; Merck Sharp and Dohm (Australia). Pty Limited, PO Box 79. Granville NSW 2 142. Australia.
TREMOR,
889
Sanitate
h. baclofen; Geigy Pharmaceuticals, division of Ciba-Geigy Corporation. Ardsley, NY 10502. i. alprazolam; The Upjon Company. 7000 Portage Road. Kalamazoo. MI 49001. j. valpormide; Abbott Laboratories, Pharmaceutical North Chicago. IL 60064.
Products Division.
j. valpormide; Abbott Laboratories, Pharmaceutical North Chicago, IL 60064.
Products Division,
Arch Phys Med Rehabil Vol74, August 1993