Research Article| Volume 367, P298-304, August 15, 2016

A study of dynamic F-waves in juvenile spinal muscular atrophy of the distal upper extremity (Hirayama disease)


      • Neck flexion caused increased repeater F-waves, suggesting HD may be more inclined to be a position-related dysfunction.
      • No differences of F-waves were observed in controls and ALS patients during neck flexion in comparison to patients with HD.
      • Significant abnormal F-waves were found in both HD and ALS patients on neck standard position.



      The study aimed to analyse changes in the upper limb F-waves during neck flexion in patients with Hirayama disease (HD).

      Material and methods

      This study included 41 healthy subjects, 38 HD patients and 24 patients with amyotrophic lateral sclerosis (ALS). Bilateral F-waves were consecutively recorded 20 times with the neck both in the standard position and after persistent neck flexion for 30 min. The persistence, minimal latencies, chronodispersion, F/M ratios and amplitudes of the F-waves and repeater F-waves were compared between the standard neck and neck flexion positions.


      During neck flexion, repeater F-waves were found in more HD patients, the percentage of both the ulnar and median repeater F-waves increased significantly, and higher F/M ratios were observed on the symptomatic side (P < 0.05). No differences in the F-waves were observed in the healthy subjects or the ALS patients during neck flexion (P > 0.05).


      HD might be more likely to present as a position-related dysfunction rather than a spinal cord-intrinsic disease. Thus, HD patients could be counselled to avoid neck flexion for long periods of time to prevent further damage, especially in the progressive stage of the disease.


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        • Hirayama K.
        • Toyokura Y.
        • Tsubaki T.
        Juvenile muscular atrophy of unilateral upper extremity: a new clinical entity [in Japanese].
        Psychiatr. Neurol. Jpn. 1959; 61: 2190-2197
        • Tan C.T.
        Juvenile muscular atrophy of distal upper extremities.
        J. Neurol. Neurosurg. Psychiatry. 1985; 48: 285
        • Ghosh P.S.
        • Moodley M.
        • Friedman N.R.
        • et al.
        Hirayama disease in children from North America.
        J. Child Neurol. 2011; 26: 1542-1547
        • Zhou B.
        • Chen L.
        • Fan D.
        • et al.
        Clinical features of Hirayama disease in mainland China.
        Amyotroph. Lateral Scler. 2010; 11: 133-139
        • Hassan K.M.
        • Sahni H.
        Nosology of juvenile muscular atrophy of distal upper extremity: from monomelic amyotrophy to Hirayama disease—Indian perspective.
        BioMed Res. Int. 2013; 2013
        • Hirayama K.
        Juvenile muscular atrophy of unilateral upper extremity (Hirayama disease)—half-century progress and establishment since its discovery.
        Brain Nerve = Shinkei kenkyu no shinpo. 2008; 60: 17-29
        • Jin X.
        • Jiang J.Y.
        • Lu F.Z.
        • et al.
        Electrophysiological differences between Hirayama disease, amyotrophic lateral sclerosis and cervical spondylotic amyotrophy.
        BMC Musculoskelet. Disord. 2014; 16: 349
        • Hirayama K.
        Non-progressive juvenile spinal muscular atrophy of the distal upper limb (Hirayama's disease).
        in: De Jong J.M.B.V. Handbook of Clinical Neurology. Elsevier, Amsterdam1991: 107-120
        • Hirayama K.
        Juvenile muscular atrophy of distal upper extremity (Hirayama disease).
        Intern. Med. (Tokyo, Japan). 2000; 39: 283-290
        • Hirayama K.
        • Tomonaga M.
        • Kitano K.
        • et al.
        Focal cervical poliopathy causing juvenile muscular atrophy of distal upper extremity: a pathological study.
        J. Neurol. Neurosurg. Psychiatry. 1987; 50: 285-290
        • Hirayama K.
        Juvenile muscular atrophy of distal upper extremity (Hirayama disease): focal cervical ischemic poliomyelopathy.
        Neuropathology. 2000; 20: 91-94
        • Hou C.
        • Han H.
        • Yang X.
        • et al.
        How does the neck flexion affect the cervical MRI features of Hirayama disease?.
        Neurol. Sci. 2012; 33: 1101-1105
        • Schroder R.
        • Keller E.
        • Flacke S.
        • et al.
        MRI findings in Hirayama's disease: flexion-induced cervical myelopathy or intrinsic motor neuron disease?.
        J. Neurol. 1999; 246: 1069-1074
        • Willeit J.
        • Kiechl S.
        • Kiechl-Kohlendorfer U.
        • et al.
        Juvenile asymmetric segmental spinal muscular atrophy (Hirayama's disease): three cases without evidence of “flexion myelopathy”.
        Acta Neurol. Scand. 2001; 104: 320-322
        • Konno S.
        • Goto S.
        • Murakami M.
        • et al.
        Juvenile amyotrophy of the distal upper extremity: pathologic findings of the dura mater and surgical management.
        Spine. 1997; 22: 486-492
        • Imai T.
        • Shizukawa H.
        • Nakanishi K.
        • et al.
        Hyperexcitability of cervical motor neurons during neck flexion in patients with Hirayama disease.
        Electromyogr. Clin. Neurophysiol. 1999; 40: 11-15
        • Polo A.
        • Currò Dossi M.
        • Fiaschi A.
        • et al.
        Peripheral and segmental spinal abnormalities of median and ulnar somatosensory evoked potentials in Hirayama's disease.
        J. Neurol. Neurosurg. Psychiatry. 2003; 74: 627-632
        • Restuccia D.
        • Rubino M.
        • Valeriani M.
        • et al.
        Cervical cord dysfunction during neck flexion in Hirayama's disease.
        Neurology. 2003; 60: 1980-1983
        • Misra U.K.
        • Kalita J.
        • Mishra V.N.
        • et al.
        Effect of neck flexion on F wave, somatosensory evoked potentials, and magnetic resonance imaging in Hirayama disease.
        J. Neurol. Neurosurg. Psychiatry. 2006; 77: 695-698
        • Ammendola A.
        • Gallo A.
        • Iannaccone T.
        • et al.
        Hirayama disease: three cases assessed by F-wave, somatosensory and motor evoked potentials and magnetic resonance imaging not supporting flexion myelopathy.
        Neurol. Sci. 2008; 29: 303-311
        • Lu F.
        • Wang H.
        • Jiang J.
        • et al.
        Efficacy of anterior cervical decompression and fusion procedures for monomelic amyotrophy treatment: a prospective randomized controlled trial: clinical article.
        J. Neurosurg. Spine. 2013; 19: 412-419
        • Kimura J.
        Peripheral Nerve Diseases.
        Elsevier Health Sciences, New York2006
        • Tang L.M.
        • Schwartz M.S.
        • Swash M.
        Postural effects on F wave parameters in lumbosacral root compression and canal stenosis.
        Brain. 1988; 111: 207-213
        • Zhu Y.
        • Starr A.
        • Haldeman S.
        • et al.
        Soleus H-reflex to S1 nerve root stimulation.
        Electroencephalogr. Clin. Neurophysiol. 1998; 109: 10-14
        • Huang Y.C.
        • Ro L.S.
        • Chang H.S.
        • et al.
        A clinical study of Hirayama disease in Taiwan.
        Muscle Nerve. 2008; 37: 576-582
        • Tashiro K.
        • Kikuchi S.
        • Itoyama Y.
        • et al.
        Nationwide survey of juvenile muscular atrophy of distal upper extremity (Hirayama disease) in Japan.
        Amyotroph. Lateral Scler. 2006; 7: 38-45
        • Zheng C.
        • Lyu F.
        • Ma X.
        • et al.
        Cervical flexion F-waves in the patients with Hirayama diseases[article in Chinese].
        Zhonghua Wai Ke Za Zhi. 2015; 53: 95-100
        • Brooks B.R.
        • Miller R.G.
        • Swash M.
        • Munsat T.L.
        El Escorial revisited: revised criteria for the diagnosis of amyotrophic lateral sclerosis.
        Amyotroph. Lateral Scler. Other Motor Neuron Disord. 2000; 1: 293-299
        • Guiloff R.J.
        • Modarres-Sadeghi H.
        Preferential generation of recurrent responses by groups of motor neurons in man. Conventional and single unit F wave studies.
        Brain. 1991; 114: 1771-1801
        • Kimura J.
        • Yanagisawa H.
        • Yamada T.
        • et al.
        Is the F wave elicited in a select group of motoneurons?.
        Muscle Nerve. 1984; 7: 392-399
        • Fisher M.A.
        AAEM Minimonograph #13: H reflexes and F waves: physiology and clinical indications.
        Muscle Nerve. 1992; 15: 1223-1233
        • Chroni E.
        • Tendero I.S.
        • Punga A.R.
        • et al.
        Usefulness of assessing repeater F-waves in routine studies.
        Muscle Nerve. 2012; 45: 477-485
        • Ibrahim I.K.
        • el-Abd M.A.
        Giant repeater F-wave in patients with anterior horn cell disorders. Role of motor unit size.
        Am. J. Phys. Med. Rehabil. 1997; 76: 281-287
        • Hachisuka A.
        • Komori T.
        • Abe T.
        • et al.
        Repeater F-waves are signs of motor unit pathology in polio survivors.
        Muscle Nerve. 2015; 51: 680-685
        • Roth G.
        • Soichot P.
        Cancellation of single F wave by double stimulation in case of chronic denervation.
        Electroencephalogr. Clin. Neurophysiol. 1995; 97: 155-158
        • Pastore-Olmedo C.
        • Gonzalez O.
        • Geijo-Barrientos E.
        A study of F-waves in patients with unilateral lumbosacral radiculopathy.
        Eur. J. Neurol. 2009; 16: 1233-1239
        • Dengler R.
        • Kossev A.
        • Wohlfahrt K.
        • et al.
        F waves and motor unit size.
        Muscle Nerve. 1992; 15: 1138-1142
        • Wang X.N.
        • Cui L.Y.
        • Liu M.S.
        • et al.
        A clinical neurophysiology study of Hirayama disease.
        Chin. Med. J. 2012; 125: 1115-1120
        • Fang J.
        • Cui L.Y.
        • Liu M.S.
        • et al.
        F wave study in amyotrophic lateral sclerosis: assessment of segmental Motoneuronal dysfunction.
        Chin. Med. J. 2015; 128: 1738-1742
        • Kimura J.
        Electrodiagnosis in Diseases of Nerve and Muscle: Principles and Practice.
        third ed. Oxford University Press, New York2001
        • Misra U.K.
        • Kalita J.
        Central motor conduction in Hirayama disease.
        Electroencephalogr. Clin. Neurophysiol. 1995; 97: 73-76