Funding support from the Motor Neuron Disease Research Institute of Australia (MNDRIA), Sylvia and Charles Viertel Charitable Foundation Clinical Investigator grant, Ramaciotti Foundation and National Health and Medical Research Council of Australia (Project grant number APP1024915)&#160;is gratefully acknowledged.&#160;

1. Patient Preparation
<ol>
	<li>Recruit patients prospectively and consecutively. Note: The following protocol is approved by the Sydney West Area Health Service Human Research Ethics Committees. Informed consent was provided by all patients. Patients were recruited prospectively and consecutively from the ALS/neuromuscular clinic at Westmead Hospital.</li>
	<li>Determine suitability of ALS patients for testing. Exclude patients who are not diagnosed with ALS or a neuromuscular disorder.</li>
	<li>Exclude patients with a coexistent focal neuropathy, median neuropathy at the wrist or ulnar neuropathy at elbow.</li>
	<li>Exclude patients with a generalized neuropathy, such as diabetic polyneuropathy.</li>
	<li>Extensively investigate and clinically follow-up patients to confirm the diagnosis of ALS or neuromuscular mimic disorders.</li>
	<li>Ensure that informed consent is provided by all patients, including ALS and neuromuscular mimic disorder patients, for all the neurophysiological procedures.</li>
</ol>
2. Clinical Assessment
<ol>
	<li>Determine the clinical staging of all ALS patients by using the Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) score18.</li>
	<li>Determine the rate of disease progression in all ALS patients according to the previously reported formula; 
	(48-ALSFRS-R)/duration of symptoms)19.</li>
	<li>Determine muscle strength in all patients using the Medical Research Council (MRC) rating scale20. Develop a total MRC score comprising upper limb (shoulder abduction; elbow flexion; elbow extension; wrist dorsiflexion; finger abduction; thumb abduction, total score 60) and lower limb (hip flexion; knee extension; ankle dorsiflexion, total score 30) muscle groups. The total MRC score should be 90 if muscle strength is normal.</li>
	<li>Determine the site of disease onset, defined as bulbar or limb, in all ALS patients.</li>
</ol>
3. Neurophysiological Assessment
<ol>
	<li>Undertake motor nerve conduction studies on the median and ulnar nerves with compound muscle action potential (CMAP) responses recorded from the abductor pollicis brevis (APB), first dorsal interosseous (FDI) and abductor digit minimi (ADM) muscles.</li>
	<li>Prepare the stimulating sites at the wrist, by cleaning the skin surface with an abrasive gel to reduce skin resistance, followed by application of an alcohol wipe. Set the stimulating current to 20% above the intensity required to produce a maximal CMAP response (supramaximal current).</li>
	<li>Ensure that the selected stimulation site exhibits the lowest threshold for stimulation such that volume conduction is avoided.</li>
	<li>Prepare recording site over each muscle by cleaning the skin surface with an abrasive gel to reduce skin resistance, followed by application of an alcohol wipe.</li>
	<li>Record the size of the compound motor action potential (CMAP) from the APB, ADM, and FDI muscles. Responses to be recorded by 10&#160;mm gold disc electrodes positioned in a belly tendon arrangement over each muscle. Specifically, position the active electrode over the midpoint of the respective muscle ensuring a negative take-off of the CMAP response, while reference electrode to be positioned over the base of thumb (APB and FDI CMAP recordings) and base of digit 5 (for ADM CMAP recordings).</li>
	<li>Set the distance between the stimulating cathode and active electrode for APB and ADM compound motor action potential responses to 5 cm and the distance to the FDI at 8 cm.</li>
	<li>Position the electrosurgical neutral earth plate on the dorsal aspect of the hand, between stimulating and G1 electrode, with conductive gel to reduce artifact. Prior to application of the neutral earth prepare the site by cleaning the skin surface with an abrasive gel to reduce skin resistance, followed by application of an alcohol wipe.</li>
	<li>Ensure the filter settings are between 3 Hz (low-frequency filter) and 10 KHz (high-frequency filter).</li>
	<li>Ensure that the sweep speed is set to 20 msec, or 2 msec/division.</li>
	<li>Ensure that the sensitivity for recording CMAP responses is set to 5 mV.</li>
	<li>Monitor temperature at the site of stimulation throughout the study and ensure that the limb temperature is maintained at 32 &#176;C.</li>
</ol>
4. Analysis and Interpretation
<ol>
	<li>Measure baseline-to-peak CMAP amplitudes (mV) over the APB, FDI and ADM muscles in ALS patients and the neuromuscular mimic disease controls.</li>
	<li>Calculate the split&#160;hand index (Figure&#160;1) by multiplying the CMAP amplitude recorded over the APB and FDI muscles, and dividing this product by the CMAP amplitude recorded over the ADM muscle, as follows: 
	SI = APB CMAP * FDI CMAP 
	_________________________ 
	&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;ADM CMAP</li>
	<li>Determine the diagnostic utility of the split hand index by comparing the SI values between ALS patients and neuromuscular mimic disorder pathological controls according to the standards for reporting of diagnostic accuracy (STARD) criteria.</li>
	<li>Determine optimal diagnostic cutoff values for the split&#160;hand index by using the receiver operating characteristic (ROC) curves. Derive ROC curve by plotting the sensitivity (y-axis) and 1-specificty (x-axis) for SI values derived from ALS and neuromuscular disorder patients.</li>
</ol>

<ol>
	<li>Weber, M., Eisen, A., Stewart, H., Hirota, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+split+hand+in+ALS+has+a+cortical+basis.">The split hand in ALS has a cortical basis.</a> J. Neurol. Sci. 180, 66-70 (2000).</li><li>Wilbourn, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+&#8220;split+hand+syndrome&#8220;.">The &#8220;split hand syndrome&#8220;.</a> Muscle Nerve. 23, 138 (2000).</li><li>Kuwabara, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dissociated+small+hand+muscle+atrophy+in+amyotrophic+lateral+sclerosis:+frequency,+extent,+and+specificity.">Dissociated small hand muscle atrophy in amyotrophic lateral sclerosis: frequency, extent, and specificity.</a> Muscle Nerve. 37, 426-430 (2008).</li><li>Kuwabara, S., Mizobuchi, K., Ogawara, K., Hattori, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dissociated+small+hand+muscle+involvement+in+amyotrophic+lateral+sclerosis+detected+by+motor+unit+number+estimates.">Dissociated small hand muscle involvement in amyotrophic lateral sclerosis detected by motor unit number estimates.</a> Muscle Nerve. 22, 870-873 (1999).</li><li>Menon, P., Kiernan, M. C., Vucic, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Appearance,+phenomenology+and+diagnostic+utility+of+the+split+hand+in+amyotrophic+lateral+sclerosis.">Appearance, phenomenology and diagnostic utility of the split hand in amyotrophic lateral sclerosis.</a> Neurodegener. Dis. Manag. 1, 457-462 (2011).</li><li>Brooks, B. R., Miller, R. G., Swash, M., Munsat, T. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=El+Escorial+revisited:+revised+criteria+for+the+diagnosis+of+amyotrophic+lateral+sclerosis.">El Escorial revisited: revised criteria for the diagnosis of amyotrophic lateral sclerosis.</a> Amyotroph Lateral Scler. 1, 293-299 (2000).</li><li>Swash, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Early+diagnosis+of+ALS/MND.">Early diagnosis of ALS/MND.</a> J. Neurol. Sci. 160 suppl 1, 833-836 (1998).</li><li>Chio, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=ISIS+Survey:+an+international+study+on+the+diagnostic+process+and+its+implications+in+amyotrophic+lateral+sclerosis.">ISIS Survey: an international study on the diagnostic process and its implications in amyotrophic lateral sclerosis.</a> J. Neurol. 246 Suppl 3, (1999).</li><li>Turner, M. R., Kiernan, M. C., Leigh, P. N., Talbot, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biomarkers+in+amyotrophic+lateral+sclerosis.">Biomarkers in amyotrophic lateral sclerosis.</a> Lancet Neurol. 8, 94-109 (2009).</li><li>Traynor, B. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clinical+features+of+amyotrophic+lateral+sclerosis+according+to+the+El+Escorial+and+Airlie+House+diagnostic+criteria:+A+population-based+study.">Clinical features of amyotrophic lateral sclerosis according to the El Escorial and Airlie House diagnostic criteria: A population-based study.</a> Arch. Neurol. 57, 1171-1176 (2000).</li><li>de Carvalho, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrodiagnostic+criteria+for+diagnosis+of+ALS.">Electrodiagnostic criteria for diagnosis of ALS.</a> Clin. Neurophysiol. 119, 497-503 (2008).</li><li>de Carvalho, M., Swash, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Awaji+diagnostic+algorithm+increases+sensitivity+of+El+Escorial+criteria+for+ALS+diagnosis.">Awaji diagnostic algorithm increases sensitivity of El Escorial criteria for ALS diagnosis.</a> Amyotroph Lateral Scler. 10, 53-57 (2009).</li><li>Boekestein, W. A., Kleine, B. U., Hageman, G., Schelhaas, H. J., Zwarts, M. 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Psychiatr. 81, 646-649 (2010).</li><li>Noto, Y. I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Awaji+ALS+criteria+increase+the+diagnostic+sensitivity+in+patients+with+bulbar+onset.">Awaji ALS criteria increase the diagnostic sensitivity in patients with bulbar onset.</a> Clin. Neurophysiol. 123, 382-385 (2012).</li><li>Schrooten, M., Smetcoren, C., Robberecht, W., Van Damme, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Benefit+of+the+Awaji+diagnostic+algorithm+for+amyotrophic+lateral+sclerosis:+A+prospective+study.">Benefit of the Awaji diagnostic algorithm for amyotrophic lateral sclerosis: A prospective study.</a> Ann. 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The authors have nothing to disclose.

The present study reports on the diagnostic utility of the split hand index in ALS, a novel neurophysiological diagnostic biomarker. The SI reliably distinguished ALS from neuromuscular disorders, with an optimal diagnostic cut-off value of 5.2. The reduction in the SI was most prominent in limb-onset ALS patients. Importantly, a substantial proportion of ALS patients that were classified in the diagnostic &#8220;possible&#8221; category as per the recently developed diagnostic criteria11, exhibited an abnorma...

The split&#160;hand, refers to preferential atrophy of the thenar complex group of intrinsic hand muscles [abductor pollicis brevis (APB) and first dorsal interosseous (FDI)], with relative preservation of hypothenar muscles, and is a specific and early clinical feature of amyotrophic lateral sclerosis (ALS)1-4. The finding that the split hand sign is specific for ALS, suggests a potential role for the split hand sign as a diagnostic biomarker in ALS3.
Quantification of the split&#160;hand sign, through the development of a novel neurophysiological biomarker, may further aid in ALS diagnosis. Specifically, the split&#160;hand index (SI), which quantifies the split&#160;hand phenomenon, is derived by multiplying the compound muscle action potential (CMAP) amplitude recorded over the thenar complex muscles (APB and FDI), and dividing this product by the CMAP amplitude recorded over the hypothenar muscles (namely the abductor digiti minimi, ADM)5.
The diagnosis of ALS relies largely on clinically based criteria encompassing a combination of upper and lower motor neuron signs6. These criteria, however, were deemed insensitive especially in establishing a diagnosis of ALS in the early stages of the disease process7-10. A recent modification of the diagnostic criteria were developed11, and although these criteria appear to increase the diagnostic sensitivity12-16, the increase sensitivity seems restricted to bulbar-onset ALS patients15.
In the absence of a pathognomonic test, the diagnosis of ALS may be significantly delayed8. Ultimately, the institution of neuroprotective therapies and recruitment into clinical trials may be delayed, perhaps beyond the critical therapeutic window period9,17. Consequently, the diagnostic utility of the SI was prospectively assessed in sporadic ALS patients.

<table border="0" cellpadding="0" cellspacing="0">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:125px;"></td>
			<td style="width:120px;"></td>
			<td style="width:136px;"></td>
			<td style="width:203px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Abrasive gel (Nu Prep)</td>
			<td>Weaver and Company</td>
			<td>N-TA\/P\H-3 ENG</td>
			<td>Skin preperation</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td colspan="2">(www.doweaver.com)</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Alcohol wipe</td>
			<td>Triad Disposables</td>
			<td>103101</td>
			<td>Skin preperation</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td colspan="2">(www.triad-group.net)</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Recording gel (Ten20 Conductive gel)</td>
			<td>Weaver and Company</td>
			<td>N-TA\/P\H-3 ENG</td>
			<td>Recording motor responses</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td colspan="2">(www.doweaver.com)</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Amyotrophic lateral sclerosis rating scale-revised questionnaire</td>
			<td>Publication&#160;</td>
			<td>Experimental builder</td>
			<td>Stage disease</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td colspan="2">(see Methods and References)</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Medical Research Council muscle strength scale</td>
			<td>Medical Research Council-UK</td>
			<td>Experimental builder</td>
			<td>Stage disease</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td colspan="2">(see Methods and References)</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td colspan="2" height="20" style="height:20px;">Table of equipment used</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Name of the equipment used</td>
			<td>Company</td>
			<td>Catalog number</td>
			<td>Comments</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Nerve conduction machine (Synergy/Nicolet EDX)</td>
			<td>CareFusion (www.carefusion.com/medical-products/neurology)</td>
			<td>SA110106M</td>
			<td>To measure split hand index</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Synergy software</td>
			<td>CareFusion</td>
			<td>765654679</td>
			<td>To measure split hand index</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td colspan="3">(www.carefusion.com/medical-products/neurology)</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Tem millimeter gold cup disc electrodes</td>
			<td>Grass Technologies</td>
			<td>F-E5GH-60</td>
			<td>To record motor responses</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td colspan="2">(www.grasstechnologies.com)</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Neural earth plate</td>
			<td>Westmead Hospital</td>
			<td>Experimental builder</td>
			<td>To record limb temperature</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;"></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Thermometer</td>
			<td>Westmead Hospital</td>
			<td>Experimental builder</td>
			<td>To record limb temperature</td>
		</tr>
	</tbody>
</table>

utility of dissociated intrinsic hand muscle atrophy in the diagnosis of amyotrophic lateral sclerosis

The split hand phenomenon refers to predominant wasting of thenar muscles and is an early and specific feature of amyotrophic lateral sclerosis (ALS). A novel split hand index (SI) was developed to quantify the split hand phenomenon, and its diagnostic utility was assessed in ALS patients. The split hand index was derived by dividing the product of the compound muscle action potential (CMAP) amplitude recorded over the abductor pollicis brevis and first dorsal interosseous muscles by the CMAP amplitude recorded over the abductor digiti minimi muscle. In order to assess the diagnostic utility of the split hand index, ALS patients were prospectively assessed and their results were compared to neuromuscular disorder patients. The split hand index was significantly reduced in ALS when compared to neuromuscular disorder patients (P&#60;0.0001). Limb-onset ALS patients exhibited the greatest reduction in the split&#160;hand index, and a value of 5.2 or less reliably differentiated ALS from other neuromuscular disorders. Consequently, the split&#160;hand index appears to be a novel diagnostic biomarker for ALS, perhaps facilitating an earlier diagnosis.

Clinical Phenotype
In total, 44 ALS patients were studied, of which 76% (N=33) were classified as definite or probable and 24% (N=11) as possible ALS according to the Awaji criteria11. The diagnosis of ALS was confirmed in the &#8220;possible&#8221; cohort after extensive investigations and clinical follow-up for up to 3 years and 53% died during this period. Bulbar-onset disease was evident in 41%, while limb-onset in 59% of ALS patients. At the time of assessment, mean dise...

Watch this Scientific Journal Video about Utility of Dissociated Intrinsic Hand Muscle Atrophy in the Diagnosis of Amyotrophic Lateral Sclerosis at JoVE.com

Utility of Dissociated Intrinsic Hand Muscle Atrophy in the Diagnosis of Amyotrophic Lateral Sclerosis

Dissociated atrophy of intrinsic hand muscles, termed the split hand, appears to be a specific feature of amyotrophic lateral sclerosis (ALS).&#160;Consequently, a novel neurodiagnostic test, termed the split hand&#160;index, was developed to quantify the clinical phenomenon of the split hand, which differentiated ALS from mimic disorders.

The split hand phenomenon refers to predominant wasting of thenar muscles and is an early and specific feature of amyotrophic lateral sclerosis (ALS). A ...

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Medicine

31.2K Views.  Westmead Hospital. Dissociated atrophy of intrinsic hand muscles, termed the split hand, appears to be a specific feature of amyotrophic lateral sclerosis (ALS). Consequently, a novel neurodiagnostic test, termed the split hand index, was developed to quantify the clinical phenomenon of the split hand, which differentiated ALS from mimic disorders.

Video: Utility of Dissociated Intrinsic Hand Muscle Atrophy in the Diagnosis of Amyotrophic Lateral Sclerosis

A Protocol for Comprehensive Assessment of Bulbar Dysfunction in Amyotrophic Lateral Sclerosis (ALS)

Improved methods for assessing bulbar impairment are necessary for expediting diagnosis of bulbar dysfunction in ALS, for predicting disease progression across speech subsystems, and for addressing the critical need for sensitive outcome measures for ongoing experimental treatment trials. To address this need, we are obtaining longitudinal profiles of bulbar impairment in 100 individuals based on a comprehensive instrumentation-based assessment that yield objective measures. Using instrumental approaches to quantify speech-related behaviors is very important in a field that has primarily relied on subjective, auditory-perceptual forms of speech assessment1. Our assessment protocol measures performance across all of the speech subsystems, which include respiratory, phonatory (laryngeal), resonatory (velopharyngeal), and articulatory. The articulatory subsystem is divided into the facial components (jaw and lip), and the tongue. Prior research has suggested that each speech subsystem responds differently to neurological diseases such as ALS. The current protocol is designed to test the performance of each speech subsystem as independently from other subsystems as possible. The speech subsystems are evaluated in the context of more global changes to speech performance. These speech system level variables include speaking rate and intelligibility of speech.
The protocol requires specialized instrumentation, and commercial and custom software. The respiratory, phonatory, and resonatory subsystems are evaluated using pressure-flow (aerodynamic) and acoustic methods. The articulatory subsystem is assessed using 3D motion tracking techniques. The objective measures that are used to quantify bulbar impairment have been well established in the speech literature and show sensitivity to changes in bulbar function with disease progression. The result of the assessment is a comprehensive, across-subsystem performance profile for each participant. The profile, when compared to the same measures obtained from healthy controls, is used for diagnostic purposes. Currently, we are testing the sensitivity and specificity of these measures for diagnosis of ALS and for predicting the rate of disease progression. In the long term, the more refined endophenotype of bulbar ALS derived from this work is expected to strengthen future efforts to identify the genetic loci of ALS and improve diagnostic and treatment specificity of the disease as a whole. The objective assessment that is demonstrated in this video may be used to assess a broad range of speech motor impairments, including those related to stroke, traumatic brain injury, multiple sclerosis, and Parkinson disease.

A Protocol for Comprehensive Assessment of Bulbar Dysfunction in Amyotrophic Lateral Sclerosis ALS

Objective assessments of the physiological mechanisms that support speech are needed to monitor disease onset and progression in persons with ALS and to quantify treatment effects in clinical trials. In this video, we present a comprehensive, instrumentation-based protocol for quantifying speech motor performance in clinical populations.

Improved methods for assessing bulbar impairment are necessary for expediting diagnosis of bulbar dysfunction in ALS, for predicting disease progression ...

Intraspinal Cell Transplantation for Targeting Cervical Ventral Horn in Amyotrophic Lateral Sclerosis and Traumatic Spinal Cord Injury

Respiratory compromise due to phrenic motor neuron loss is a debilitating consequence of a large proportion of human traumatic spinal cord injury (SCI) cases 1 and is the ultimate cause of death in patients with the motor neuron disorder, amyotrophic laterals sclerosis (ALS) 2.
ALS is a devastating neurological disorder that is characterized by relatively rapid degeneration of upper and lower motor neurons. Patients ultimately succumb to the disease on average 2-5 years following diagnosis because of respiratory paralysis due to loss of phrenic motor neuron innnervation of the diaphragm 3. The vast majority of cases are sporadic, while 10% are of the familial form. Approximately twenty percent of familial cases are linked to various point mutations in the Cu/Zn superoxide dismutase 1 (SOD1) gene on chromosome 21 4. Transgenic mice 4,5 and rats 6 carrying mutant human SOD1 genes (G93A, G37R, G86R, G85R) have been generated, and, despite the existence of other animal models of motor neuron loss, are currently the most highly used models of the disease.
Spinal cord injury (SCI) is a heterogeneous set of conditions resulting from physical trauma to the spinal cord, with functional outcome varying according to the type, location and severity of the injury 7. Nevertheless, approximately half of human SCI cases affect cervical regions, resulting in debilitating respiratory dysfunction due to phrenic motor neuron loss and injury to descending bulbospinal respiratory axons 1. A number of animal models of SCI have been developed, with the most commonly used and clinically-relevant being the contusion 8.
Transplantation of various classes of neural precursor cells (NPCs) is a promising therapeutic strategy for treatment of traumatic CNS injuries and neurodegeneration, including ALS and SCI, because of the ability to replace lost or dysfunctional CNS cell types, provide neuroprotection, and deliver gene factors of interest 9.
Animal models of both ALS and SCI can model many clinically-relevant aspects of these diseases, including phrenic motor neuron loss and consequent respiratory compromise 10,11. In order to evaluate the efficacy of NPC-based strategies on respiratory function in these animal models of ALS and SCI, cellular interventions must be specifically directed to regions containing therapeutically relevant targets such as phrenic motor neurons. We provide a detailed protocol for multi-segmental, intraspinal transplantation of NPCs into the cervical spinal cord ventral gray matter of neurodegenerative models such as SOD1G93A mice and rats, as well as spinal cord injured rats and mice 11.

Neural precursor transplantation is a promising strategy for protecting and/or replacing lost/dysfunctional cervical phrenic motor neurons in spinal cord injury (SCI) and the motor neuron disorder, amyotrophic laterals sclerosis (ALS). We provide a protocol for cell delivery to cervical spinal cord ventral horn in rodent models of ALS and SCI.

Respiratory compromise due to phrenic motor neuron loss is a debilitating consequence of a large proportion of human traumatic spinal cord injury (SCI) ...

Clinical Testing and Spinal Cord Removal in a Mouse Model for Amyotrophic Lateral Sclerosis (ALS)

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder resulting in progressive degeneration of motoneurons. Peak of onset is around 60 years for the sporadic disease and around 50 years for the familial disease. Due to its progressive course, 50% of the patients die within 30 months of symptom onset. In order to evaluate novel treatment options for this disease, genetic mouse models of ALS have been generated based on human familial mutations in the SOD gene, such as the SOD1 (G93A) mutation. Most important aspects that have to be evaluated in the model are overall survival, clinical course and motor function. Here, we demonstrate the clinical evaluation, show the conduction of two behavioural motor tests and provide quantitative scoring systems for all parameters. Because an in depth analysis of the ALS mouse model usually requires an immunohistochemical examination of the spinal cord, we demonstrate its preparation in detail applying the dorsal laminectomy method. Exemplary histological findings are demonstrated. The comprehensive application of the depicted examination methods in studies on the mouse model of ALS will enable the researcher to reliably test future therapeutic options which can provide a basis for later human clinical trials.

Clinical Testing and Spinal Cord Removal in a Mouse Model for Amyotrophic Lateral Sclerosis ALS

A mouse model for amyotrophic lateral sclerosis (ALS) is examined clinically and behaviorally. As a prerequisite for an accompanying immunohistological analysis the preparation of the spinal cord is depicted in detail.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder resulting in progressive degeneration of motoneurons. Peak of onset is around 60 ...

Real-time Digital Imaging of Leukocyte-endothelial Interaction in Ischemia-reperfusion Injury (IRI) of the Rat Cremaster Muscle

Ischemia-reperfusion injury (IRI) has been implicated in a large array of pathological conditions such as cerebral stroke, myocardial infarction, intestinal ischemia as well as following transplant and cardiovascular surgery.1 Reperfusion of previously ischemic tissue, while essential for the prevention of irreversible tissue injury, elicits excessive inflammation of the affected tissue. Adjacent to the production of reactive oxygen species, activation of the complement system and increased microvascular permeability, the activation of leukocytes is one of the principle actors in the pathological cascade of inflammatory tissue damage during reperfusion.2, 3 Leukocyte activation is a multistep process consisting of rolling, firm adhesion and transmigration and is mediated by a complex interaction between adhesion molecules in response to chemoattractants such as complement factors, chemokines, or platelet-activating factor.4
While leukocyte rolling in postcapillary venules is predominantly mediated by the interaction of selectins5 with their counter ligands, firm adhesion of leukocytes to the endothelium is selectin-controlled via binding to intercellular adhesion molecules (ICAM) and vascular cellular adhesion molecules (VCAM).6, 7 
Gold standard for the in vivo observation of leukocyte-endothelial interaction is the technique of intravital microscopy, first described in 1968.8
Though various models of IRI (ischemia-reperfusion injury) have been described for various organs, 9-12 only few are suitable for direct visualization of leukocyte recruitment in the microvascular bed on a high level of image quality.8 
We here promote the digital intravital epifluorescence microscopy of the postcapillary venule in the cremasteric microcirculation of the rat 13 as a convenient method to qualitatively and quantitatively analyze leukocyte recruitment for IRI-research in striated muscle tissue and provide a detailed manual for accomplishing the technique. We further illustrate common pitfalls and provide useful tips which should enable the reader to truly appreciate, and safely perform the method.
In a step by step protocol we depict how to get started with respiration controlled anesthesia under sufficient monitoring to keep the animal firmly anesthetized for longer periods of time. We then describe the cremasteric preparation as a thin flat sheet for outstanding optical resolution and provide a protocol for leukocyte imaging in IRI that has been well established in our laboratories.

Real-time Digital Imaging of Leukocyte-endothelial Interaction in Ischemia-reperfusion Injury IRI of the Rat Cremaster Muscle

Digital intravital epifluorescence microscopy of postcapillary venules in the cremasteric microcirculation is a convenient method to gain insights into leukocyte-endothelial interaction in vivo in ischemia-reperfusion injury (IRI) of striated muscle tissue. We here provide a detailed protocol to safely perform the technique and discuss its applications and limitations.

Ischemia-reperfusion injury (IRI) has been implicated in a large array of pathological conditions such as cerebral stroke, myocardial infarction, ...

Tibial Nerve Transection - A Standardized Model for Denervation-induced Skeletal Muscle Atrophy in Mice

The tibial nerve transection model is a well-tolerated, validated, and reproducible model of denervation-induced skeletal muscle atrophy in rodents. Although originally developed and used extensively in the rat due to its larger size, the tibial nerve in mice is big enough that it can be easily manipulated with either crush or transection, leaving the peroneal and sural nerve branches of the sciatic nerve intact and thereby preserving their target muscles. Thus, this model offers the advantages of inducing less morbidity and impediment of ambulation than the sciatic nerve transection model and also allows investigators to study the physiologic, cellular and molecular biologic mechanisms regulating the process of muscle atrophy in genetically engineered mice. The tibial nerve supplies the gastrocnemius, soleus and plantaris muscles, so its transection permits the study of denervated skeletal muscle composed of fast twitch type II fibers and/or slow twitch type I fibers. Here we demonstrate the tibial nerve transection model in the C57Black6 mouse. We assess the atrophy of the gastrocnemius muscle, as a representative muscle, at 1, 2, and 4 weeks post-denervation by measuring muscle weights and fiber type specific cross-sectional area on paraffin-embedded histologic sections immunostained for fast twitch myosin.

The tibial nerve transection model is a well-tolerated, validated, and reproducible model of skeletal muscle atrophy. The model surgical protocol is described and demonstrated in C57Black6 mice. &#160;

The tibial nerve transection model is a well-tolerated, validated, and reproducible model of denervation-induced skeletal muscle atrophy in rodents. ...

High-throughput Flow Cytometry Cell-based Assay to Detect Antibodies to N-Methyl-D-aspartate Receptor or Dopamine-2 Receptor in Human Serum

Over the recent years, antibodies against surface and conformational proteins involved in neurotransmission have been detected in autoimmune CNS diseases in children and adults. These antibodies have been used to guide diagnosis and treatment. Cell-based assays have improved the detection of antibodies in patient serum. They are based on the surface expression of brain antigens on eukaryotic cells, which are then incubated with diluted patient sera followed by fluorochrome-conjugated secondary antibodies. After washing, secondary antibody binding is then analyzed by flow cytometry. Our group has developed a high-throughput flow cytometry live cell-based assay to reliably detect antibodies against specific neurotransmitter receptors. This flow cytometry method is straight forward, quantitative, efficient, and the use of a high-throughput sampler system allows for large patient cohorts to be easily assayed in a short space of time. Additionally, this cell-based assay can be easily adapted to detect antibodies to many different antigenic targets, both from the central nervous system and periphery. Discovering additional novel antibody biomarkers will enable prompt and accurate diagnosis and improve treatment of immune-mediated disorders.

Over the recent years, live cell-based assays have been used successfully to detect antibodies against surface and conformational antigens. Here, we describe a method using high-throughput flow cytometry enabling the analysis of large cohorts of patients. Detection of novel antibodies will improve diagnosis and treatment of immune-mediated disorders.

Over the recent years, antibodies against surface and conformational proteins involved in neurotransmission have been detected in autoimmune CNS diseases ...

Ischemic Tissue Injury in the Dorsal Skinfold Chamber of the Mouse: A Skin Flap Model to Investigate Acute Persistent Ischemia

Despite profound expertise and advanced surgical techniques, ischemia-induced complications ranging from wound breakdown to extensive tissue necrosis are still occurring, particularly in reconstructive flap surgery. Multiple experimental flap models have been developed to analyze underlying causes and mechanisms and to investigate treatment strategies to prevent ischemic complications. The limiting factor of most models is the lacking possibility to directly and repetitively visualize microvascular architecture and hemodynamics. The goal of the protocol was to present a well-established mouse model affiliating these before mentioned lacking elements. Harder et al. have developed a model of a musculocutaneous flap with a random perfusion pattern that undergoes acute persistent ischemia and results in ~50% necrosis after 10 days if kept untreated. With the aid of intravital epi-fluorescence microscopy, this chamber model allows repetitive visualization of morphology and hemodynamics in different regions of interest over time. Associated processes such as apoptosis, inflammation, microvascular leakage and angiogenesis can be investigated and correlated to immunohistochemical and molecular protein assays. To date, the model has proven feasibility and reproducibility in several published experimental studies investigating the effect of pre-, peri- and postconditioning of ischemically challenged tissue.

The window of the murine dorsal skinfold chamber presented visualizes a zone of acute persistent ischemia of a musculocutaneous flap. Intravital epi-fluorescence microscopy permits for direct and repetitive assessment of the microvasculature and quantification of hemodynamics. Morphologic and hemodynamic results can further be correlated with histological and molecular analyses.

Despite profound expertise and advanced surgical techniques, ischemia-induced complications ranging from wound breakdown to extensive tissue necrosis are ...

Single-stage Dynamic Reanimation of the Smile in Irreversible Facial Paralysis by Free Functional Muscle Transfer

Unilateral facial paralysis is a common disease that is associated with significant functional, aesthetic and psychological issues. Though idiopathic facial paralysis (Bell&#8217;s palsy) is the most common diagnosis, patients can also present with a history of physical trauma, infectious disease, tumor, or iatrogenic facial paralysis. Early repair within one year of injury can be achieved by direct nerve repair, cross-face nerve grafting or regional nerve transfer. It is due to muscle atrophy that in long lasting facial paralysis complex reconstructive methods have to be applied. Instead of one single procedure, different surgical approaches have to be considered to alleviate the various components of the paralysis.
The reconstruction of a spontaneous dynamic smile with a symmetric resting tone is a crucial factor to overcome the functional deficits and the social handicap that are associated with facial paralysis. Although numerous surgical techniques have been described, a two-stage approach with an initial cross-facial nerve grafting followed by a free functional muscle transfer is most frequently applied. In selected patients however, a single-stage reconstruction using the motor nerve to the masseter as donor nerve is superior to a two-stage repair. The gracilis muscle is most commonly used for reconstruction, as it presents with a constant anatomy, a simple dissection and minimal donor site morbidity.
Here we demonstrate the pre-operative work-up, the post-operative management, and precisely describe the surgical procedure of single-stage microsurgical reconstruction of the smile by free functional gracilis muscle transfer in a step by step protocol. We further illustrate common pitfalls and provide useful tips which should enable the reader to truly comprehend the procedure. We further discuss indications and limitations of the technique and demonstrate representative results.

The use of the masseteric nerve as donor nerve represents a single-stage alternative to the criterion standard two-stage procedure of cross-facial nerve grafting and free muscle transfer in facial paralysis. We provide a detailed description to safely perform this technique with a gracilis muscle transfer and discuss indications and limitations.

Unilateral facial paralysis is a common disease that is associated with significant functional, aesthetic and psychological issues. Though idiopathic ...

A Method of Trigonometric Modelling of Seasonal Variation Demonstrated with Multiple Sclerosis Relapse Data

This report describes a novel Stata-based application of trigonometric regression modelling to 55 years of multiple sclerosis relapse data from 46 clinical centers across 20 countries located in both hemispheres. Central to the success of this method was the strategic use of plot analysis to guide and corroborate the statistical regression modelling. Initial plot analysis was necessary for establishing realistic hypotheses regarding the presence and structural form of seasonal and latitudinal influences on relapse probability and then testing the performance of the resultant models. Trigonometric regression was then necessary to quantify these relationships, adjust for important confounders and provide a measure of certainty as to how plausible these associations were. Synchronization of graphing techniques with regression modelling permitted a systematic refinement of models until best-fit convergence was achieved, enabling novel inferences to be made regarding the independent influence of both season and latitude in predicting relapse onset timing in MS. These methods have the potential for application across other complex disease and epidemiological phenomena suspected or known to vary systematically with season and/or geographic location.

Combining plot analysis with trigonometric regression is a robust method for exploring complex, cyclical phenomena such as relapse onset timing in multiple sclerosis (MS). This method enabled unbiased characterisation of seasonal trends in relapse onset permitting novel inferences around the influence of seasonal variation, ultraviolet radiation (UVR) and latitude.

This report describes a novel Stata-based application of trigonometric regression modelling to  55 years of multiple sclerosis relapse data from 46 ...

Design, Fabrication, and Administration of the Hand Active Sensation Test (HASTe)

The concept of personalizing neurologic rehabilitation, based on individual impairments, has experienced a recent surge. In parallel, the number of outcome measures of upper extremity motor performance has grown. However, clinicians and researchers lack practical, quantitative measures of the hand&#8217;s natural role as a receptor of the environment. The Hand Active Sensation Test (HASTe), developed by Williams and colleagues in 2006, is a valid and reliable measure of haptic performance. Though not available commercially, the HASTe can be fabricated from inexpensive materials, and it has been used successfully to identify impairments in haptic touch in individuals with stroke. (Williams, 2006). This paper presents the methods of design and fabrication of the HASTe testing kit, as well as a visual screen to be used during administration, and instructions for the tests administration and scoring.

Design, Fabrication, and Administration of the Hand Active Sensation Test HASTe

The Hand Active Sensation Test (HASTe) is a valid and reliable measure of haptic performance, which has been used successfully to identify impaired haptic touch in individuals with stroke. The purpose of this paper is to describe the design, fabrication and administration of the HASTe.

The concept of personalizing neurologic rehabilitation, based on individual impairments, has experienced a recent surge. In parallel, the number of ...