all research articles on LMN UMN lesions from Pubmed

1. Li XF, Dai LY
Acute central cord syndrome: injury mechanisms and stress features. [Journal Article, Research Support,
Non-U.S. Gov't]
Spine (Phila Pa 1976) 2010 Sep 1; 35(19):E955-64.
Numerical techniques were used to study the mechanisms of acute central cord syndrome.To analyze the
features of stress distribution in the cervical cord under different injury conditions using finite element model
of the cervical cord and to improve the understanding of the possible pathogenesis of acute central cord
syndrome.Acute central cord spinal injury was initially attributed to hemorrhagic damage to the central
portion of the spinal cord, but recent histopathologic studies showed that it was predominantly a white
matter injury. The precise anatomic location of neuronal injury and the etiology of the clinical manifestation
were poorly understood.Cervical cord injury was simulated using a finite element model of the cervical
enlargement described previously, with the model loaded under 3 traumatic postures: neutral, flexion, and
extension. Five traumatic conditions were simulated and analyzed: hyperextension with the pinch force
directed to the anterior (A) or posterior (B); flexion injuries (C), vertical compression with the pinch force
directed to the anterior (D) or posterior (E). After simulation, several representative cross-sections of each
traumatic pattern were selected. In each cross-section, the average von Mises stress of 9 regions, such as
anterior funiculus, lateral part of the lateral funiculus, medial part of the lateral funiculus, lateral part of the
posterior funiculus, medial part of the posterior funiculus, anterior horn, the bottom of anterior horn, the
cervix cornu posterioris, the caput cornu posterioris, and the apex cornu posterioris was recorded.High
localized stress occurred at the portion under compression injury and the level above it. High localized stress
tended to occur at the lateral part of the anterior horn motor neurons innervating the hand muscles in
traumatic conditions A and D. Under conditions A, D, and E, the average localized stress at the anterior and
posterior horn of the gray matter was higher than that at the white matter in all selected cross-sections, and
the stress was higher at the anterior funiculus, the medial part of the lateral funiculus, and the lateral part
of the posterior funiculus in the white matter. Under conditions B and C, the differences of the localized
stress between the gray and the white matter were not as significant as under conditions A, D, and E, and
the stress was lower at the medial part of the lateral funiculus than that at the lateral part of the posterior
funiculus. Under all traumatic conditions, the average stress at the lateral part was higher than that at the
medial part of the posterior funiculus.Three common traumatic patterns: hyperextension, flexion, and
vertical compression, could be the possibly underlying injury mechanisms of the central cervical cord
syndrome according to the results of the current finite element analysis. The stress features under different
injury conditions were not in complete accord. High stress mainly occurred at the posterior horn, the
anterior horn, and the adjacent white matter. The centermost lesion was not common in mild central cord
injuries. The upper extremity weakness should be ascribed to the damage at the corticospinal tract and the
motor neurons in the anterior horn. Hyperpathia probably resulted from injuries to the posterior horn, the
anterior funiculus, and the fasciculus cuneatus. Just as there are varieties of the localized stress features in
central cord injuries, variations in clinical presentations were common.
van der Graaff MM, de Jong JM, Baas F, de Visser M
Upper motor neuron and extra-motor neuron involvement in amyotrophic lateral sclerosis: a clinical and
brain imaging review. [Journal Article, Research Support, Non-U.S. Gov't, Review]
Neuromuscul Disord 2009 Jan; 19(1):53-8.
There is an ongoing discussion whether ALS is primarily a disease of upper motor neurons or lower motor
neurons. We undertook a review to assess how new insights have contributed to solve this controversy. For
this purpose we selected relevant publications from 1995 onwards focussing on (1) primary targets and
disease progression in ALS and variants of ALS, (2) brain imaging markers for upper motor neuron lesion,
and (3) evidence for ALS being a multisystem disorder. Clinically, upper motor and lower motor neuron
symptoms can occur in any order over time. Brain imaging markers show upper motor neuron involvement
in early disease. Overlap syndromes of ALS and dementia, and involvement of autonomic and sensory
nerves occur frequently. PET/SPECT scans, functional MRI and voxel based morphometry studies clearly
show abnormalities in extra-motor areas of the brain. Pathologically, the 43 kDa TAR DNA-binding protein
(TDP-43) provides a clue to these overlapping disorders. In conclusion, evidence accumulates that ALS is a
multisystem disorder rather than a pure lower and/or upper motor neuron disorder.

2. Campanini I, Merlo A, Farina D
Motor unit discharge pattern and conduction velocity in patients with upper motor neuron syndrome.
[Journal Article, Research Support, Non-U.S. Gov't]
J Electromyogr Kinesiol 2009 Feb; 19(1):22-9.
Motor unit properties were analyzed in patients with upper motor neuron syndrome (UMNS). Multi-channel
surface electromyographic (EMG) signals were recorded for 300s from the biceps brachii muscle of seven
male subacute patients (time from lesion, mean+/-SE, 4.9+/-1.0 months). In three patients, both arms
were investigated, leading to 10 recorded muscles. Patients were analyzed in rest-like condition with motor
units activated due to pathological muscle overactivity. For a total of 12 motor units, the complete discharge
pattern was extracted from EMG decomposition. Interpulse interval variability was 7.8+/-0.9%. At minimum
discharge rate (6.4+/-0.4 pulses per second, pps), conduction velocity was smaller than at maximum
discharge rate (12.0+/-0.9pps) in all motor units (3.60+/-0.21m/s vs. 3.84+/-0.20m/s). Conduction
velocity changed by 1.35+/-0.48% (different from zero, P<0.01) for each increase of 1pps in discharge rate.
It was concluded that conduction velocity of low-threshold motor units in subacute patients with UMNS had
similar values as reported in healthy subjects and was positively correlated to instantaneous discharge rate
(velocity recovery function of muscle fibers).
Brown JA
Recovery of motor function after stroke. [Journal Article, Review]
Prog Brain Res 2006.:223-8.
Improvement of motor activity may occur after stroke. It may be because of recovery of marginally
functional neurons. It may also occur by relearning, a process that strengthens existing pathways and may
lead to new functional or structural changes- neuroplasticity. Clinical investigation into the treatment of
chronic pain after thalamic infarction has shown improvement in motor function when pain relief is achieved
with motor cortex stimulation. More recently, laboratory studies in rats and primates demonstrate significant
improvement in forelimb reaching tasks in rats and primates after induced ischemic cortical infarction when
rehabilitation is paired with stimulation of the injured cortex and cortical margin at low frequency (50 Hz).
Structural changes have also been observed. Dendritic density in layer V of the cortex near the lesion
increases after cortical stimulation, consistent with a restorative cortical plasticity. Also, stimulation
combined with rehabilitation increases the area of the injured cortex from which movements can be evoked
in response to stimulation of the injured cortex in rats. Unilateral cortical stimulation reduces secondary
cortical hyperexcitability in the impaired hemisphere after stroke. These findings form the basis for the first
clinical study motor cortex stimulation after chronic stroke in humans. A prospective, randomized
multicenter study of subthreshold motor cortical electrical stimulation during rehabilitation in patients has
been completed. The eight patients entered into this study had weakness from a stroke that occurred at
least four months before enrollment. Results demonstrate that the treatment is safe. In addition, there was
significant improvement in upper extremity function. These improvements persisted through the 12-week
follow-up assessment period after completion of stimulation and rehabilitation. Recently, non-invasive
transcranial magnetic stimulation of the motor cortex demonstrates improvements in hand function that
persist after stimulation for at least 25 minutes. Such work represents a paradigm shift in the approach
towards rehabilitation of the stroke-injured brain away from pharmacologic flooding of neuronal receptors,
instead towards targeted physiologic stimulation.
Brunelli G
Research on the possibility of overcoming traumatic paraplegia and its first clinical results. [Journal Article,
Review]
Curr Pharm Des 2005; 11(11):1421-8.
The interruption of the continuity of the spinal cord is still an incurable lesion. In contrast with the peripheral
nerves, the axons regenerating from the mother cells of the brain do not progress inside the cord. The
reasons of this "non-permissiveness" are still unclear. This article describes the attempts of the author to
overcome this non-permissiveness by means of a research that began in 1980 on rats, and continued since
1993 on monkeys. Results of the research on experimental animals were good and convincing so that this
operation has been performed on fully informed human being volunteers affected by total severance of the
cord between T8 and T11. Results of the first clinical cases are presented regarding operations performed

3. either by rerouting the ulnar nerve to the lower limbs, or connecting the rostral stump of the severed cord
with peripheral nerves of the hip to obtain rudimentary, but efficient, walking. Recovery occurred well in
advance of the expected time, and continued to improve up to allow the first patient operated on by
connecting CNS with PNS to walk with sticks after having walked for some months with a walker. This
connection functioned even if the axons activating the single muscles were from mother cells dispersed in
different regions of the brain cortex. These cells fire together giving selective contraction of diverse muscles.
Furthermore, function occurred although the upper motor neuron uses the neurotransmitter glutamate,
whereas motor end plates use receptors for acetylcholine. These data are under further investigation to
determine whether the upper motor neuron changes the transmitter, or if the motor end changes its
receptors (as seems to be by the first results).
Woods NN, Brooks LR, Norman GR
The value of basic science in clinical diagnosis: creating coherence among signs and symptoms. [Journal
Article, Research Support, Non-U.S. Gov't]
Med Educ 2005 Jan; 39(1):107-12.
We investigated whether learning basic science mechanisms may have mnemonic value in helping students
remember signs and symptoms, in comparison with learning the relation between symptoms and diagnoses
directly.To compare 2 approaches to learning diagnosis: learning how features of various conditions relate to
underlying pathophysiological mechanisms and learning the conditional probabilities of features and
diseases.Undergraduate students (n = 36) were taught 4 disorders (upper motor neuron lesion, lower motor
neuron lesion, neuromuscular junction disease and muscular disease), either using basic science
explanations or (symptom x disease) probabilities. They were tested with diagnostic cases immediately after
learning and 1 week later.On the immediate test, there was no difference in the results. One week later, the
accuracy of the mechanism group remained at 0.52, but the performance of the probability group had
dropped to 0.43.Knowledge of basic science may have value in clinical diagnosis by helping students recall
or reconstruct the relationships between features and diagnoses.
Calancie B, Alexeeva N, Broton JG, Molano MR
Interlimb reflex activity after spinal cord injury in man: strengthening response patterns are consistent with
ongoing synaptic plasticity. [Comparative Study, Journal Article, Research Support, Non-U.S. Gov't,
Research Support, U.S. Gov't, P.H.S.]
Clin Neurophysiol 2005 Jan; 116(1):75-86.
Previous reports from our laboratory have described short-latency contractions in muscles of the distal
upper limb following stimulation of lower limb nerves or skin in persons with injury to the cervical spinal
cord. It takes 6 or more months for interlimb reflexes (ILR) to appear following acute spinal cord injury
(SCI), suggesting they might be due to new synaptic interconnections between lower limb sensory afferents
and motoneurons in the cervical enlargement. In this study, we asked if once formed, the strength of these
synaptic connections increased over time, a finding that would be consistent with the above hypothesis.We
studied persons with sub-acute and/or chronic cervical SCI. ILR were elicited by brief trains of electrical
pulses applied to the skin overlying the tibial nerve at the back of the knee. Responses were quantified
based on their presence or absence in different upper limb muscles. We also generated peri-stimulus time
histograms for single motor unit response latency, probability, and peak duration. Comparisons of these
parameters were made in subjects at sub-acute versus chronic stages post-injury.In persons with sub-acute
SCI, the probability of seeing ILR in a given muscle of the forearm or hand was low at first, but increased
substantially over the next 1-2 years. Motor unit responses at this sub-acute stage had a prolonged and
variable latency, with a lower absolute response probability, compared to findings from subjects with chronic
(i.e. stable) SCI.Our findings demonstrate that interlimb reflex activity, once established after SCI, shows
signs of strengthening synaptic contacts between afferent and efferent components, consistent with ongoing
synaptic plasticity.Neurons within the adult human spinal cord caudal to a lesion site are not static, but
appear to be capable of developing novel-yet highly efficacious-synaptic contacts following trauma-induced
partial denervation. In this case, such contacts between ascending afferents and cervical motoneurons do
not appear to provide any functional benefit to the subject. In fact their presence may limit the regenerative
effort of supraspinal pathways which originally innervated these motoneurons, should effort in animal
models to promote regeneration across the lesion epicenter be successfully translated to humans with
chronic SCI.
Doherty JG, Burns AS, O'Ferrall DM, Ditunno JF
Prevalence of upper motor neuron vs lower motor neuron lesions in complete lower thoracic and lumbar

4. spinal cord injuries. [Comparative Study, Journal Article, Research Support, U.S. Gov't, Non-P.H.S.]
J Spinal Cord Med 2002; 25(4):289-92.
To determine the incidence and etiology of lower motor neuron (LMN) vs upper motor neuron (UMN) lesions
in patients with complete thoracic and lumbar spinal cord injuries (SCI).Retrospective chart review.A
regional Model Spinal Cord Injury System center.A consecutive sample of medical records of patients with
lower thoracic and upper lumbar (T7-L3) complete SCI admitted from 1979 through 1996 was systematically
reviewed. Of the 306 patients evaluated, 156 subjects met inclusion criteria. The incidence and etiology of
LMN vs UMN lesions were determined for the following neurologic levels: T7-T9, T10-T12, L1-L3. Lesions
were classified as LMN, UMN, or mixed on the basis of the presence or absence of (1) the bulbocavernosus
reflex, (2) lower limb deep tendon reflexes below the neurologic level of injury, and (3) the Babinski
sign.The incidences of LMN, UMN, and mixed lesions in the T7-T9, T10-T12, and L1-L3 groups were as
follows: T7-T9 group (7.3% LMN, 85.5% UMN, 7.3% mixed), T10-T12 group (57% LMN, 17.7% UMN,
25.3% mixed),L1-L3 group (95.5% LMN, 0.0% UMN, 4.5% mixed). Etiology of injury did not significantly
influence the likelihood of a LMN lesion.One cannot determine the type of lesion (UMN vs LMN) on the basis
of the neurological level of injury. A detailed clinical examination, including sacral reflexes, is required. This
has important prognostic and therapeutic implications for bowel, bladder, and sexual function, as well as
mobility. Distinguishing UMN lesions from LMN lesions is also essential for evaluating new interventions in
clinical trials for UMN pathology.
Svantesson U, Takahashi H, Carlsson U, Danielsson A, Sunnerhagen KS
Muscle and tendon stiffness in patients with upper motor neuron lesion following a stroke. [Journal Article,
Research Support, Non-U.S. Gov't]
Eur J Appl Physiol 2000 Jul; 82(4):275-9.
The objective of this study was to investigate muscle and tendon stiffness in the triceps surae muscles in
patients who had previously had a stroke. The participants were 12 men showing slight to moderate degrees
of muscle tonus in the affected leg. All patients showed minimal or no overt clinical motor symptoms, and all
walked without mechanical aid. Muscle strengths in isometric and isokinetic activities were measured, as
was passive resistance during plantarflexion in each leg. Walking speed was also measured. Evaluations of
physical performance and muscle tone were made. Muscle and tendon stiffness was calculated from
measurements whilst passively stretching during electrical stimulation, separately for each leg. Muscle
strength was significantly higher in the non-affected than in the affected leg. Muscle stiffness was
significantly higher in the affected leg than in the non-affected leg. Tendon stiffness was significantly higher
in the non-affected than in the affected leg. The higher muscle stiffness in the affected leg might enhance
the possibility for storing elastic energy during preactivation. Lower tendon stiffness in the affected leg
might reduce the development of fatigue in movements at low velocities.
Mulcahey MJ, Smith BT, Betz RR
Evaluation of the lower motor neuron integrity of upper extremity muscles in high level spinal cord injury.
[Clinical Trial, Journal Article, Research Support, Non-U.S. Gov't]
Spinal Cord 1999 Aug; 37(8):585-91.
To evaluate the lower motor neuron (LMN) integrity of upper extremity muscles of persons with high
tetraplegia (C1-C4) in order to determine muscles available for stimulation.Fourteen subjects (23 arms)
were evaluated for LMN integrity. Muscles that elicited a functional response (grade 3 or better) to surface
electrical stimulation were considered to have intact LMN and good candidates for FES. Strength-duration
(S-D) curves were generated on muscles that showed weak (less than grade 3) or no response to surface
stimulation. Muscles were considered denervated if S-D curves were discontinuous or depicted steep,
increasing amplitude for pulse durations greater than 1 m.Muscles for grasp and release had intact LMN in
19 of 23 (83%) arms. The wrist extensors and flexors and pronator were excitable in 17 (74%), 20 (87%)
and 19 (83%) arms, respectively. The supinator demonstrated LMN lesion in 80% of the arms. Over 90% of
the biceps muscles were unresponsive to electrical stimulation and 85% and 87% of the deltoid and
supraspinatus muscles, respectively, were not electrically excitable. The latissimus dorsi and triceps muscles
were typically innervated (78% and 91%, respectively) and slightly more than half (52%) of the pectoralis
major muscles were excitable.These data suggest that application of FES in high tetraplegia for hand and
arm function would require augmentation because of the inability to stimulate the elbow flexors, deltoid and

5. rotator cuff muscles. These data also show that several paralyzed proximal muscles with intact LMN that
have been historically transferred to address shoulder paralysis in other patient populations are available for
transfer and stimulation in the population with high level spinal
Svantesson U, Osterberg U, Grimby G, Sunnerhagen KS
The standing heel-rise test in patients with upper motor neuron lesion due to stroke. [Journal Article,
Research Support, Non-U.S. Gov't]
Scand J Rehabil Med 1998 Jun; 30(2):73-80.
The objective was to investigate the fatigue process in the triceps surae during the heel-rise test (eccentric
and concentric phases) in comparison with a walking test and muscle strength. Eight men with prior stroke
and 8 age-matched healthy men participated. The electromyographic activity in form of root mean square
and mean power frequency of the gastrocnemius and soleus muscles were measured and work estimated.
Walking speed and maximal peak torque were measured and differed significantly between the patient and
reference groups. There were no significant differences between the groups nor legs concerning the number
of heel-rises or work performed. In the eccentric phase, mean power frequency decreased significantly more
in the gastrocnemius than in the soleus muscle in the reference group, while mean power frequency in the
soleus muscle tended to decrease more, though non-significantly, in the affected leg. The conclusion is that
the capacity to perform the heel-rise test in patients with prior stroke is better than plantarflexor peak
torque and walking speed.
Svantesson U, Osterberg U, Grimby G, Sunnerhagen KS
The standing heel-rise test in patients with upper motor neuron lesion due to stroke. [Journal Article,
Research Support, Non-U.S. Gov't]
Scand J Rehabil Med 1998 Jun; 30(2):73-80.
The objective was to investigate the fatigue process in the triceps surae during the heel-rise test (eccentric
and concentric phases) in comparison with a walking test and muscle strength. Eight men with prior stroke
and 8 age-matched healthy men participated. The electromyographic activity in form of root mean square
and mean power frequency of the gastrocnemius and soleus muscles were measured and work estimated.
Walking speed and maximal peak torque were measured and differed significantly between the patient and
reference groups. There were no significant differences between the groups nor legs concerning the number
of heel-rises or work performed. In the eccentric phase, mean power frequency decreased significantly more
in the gastrocnemius than in the soleus muscle in the reference group, while mean power frequency in the
soleus muscle tended to decrease more, though non-significantly, in the affected leg. The conclusion is that
the capacity to perform the heel-rise test in patients with prior stroke is better than plantarflexor peak
torque and walking speed.
Herdmann J, Dvorák J, Bock WJ
Motor evoked potentials in patients with spinal disorders: upper and lower motor neurone affection. [Journal
Article, Research Support, Non-U.S. Gov't]
Electromyogr Clin Neurophysiol 1992 Jul-Aug; 32(7-8):323-30.
Motor evoked potentials (MEP) following magnetoelectric stimulation allow for detection and quantification of
a lesion of the central and peripheral motor pathways. MEP latency is a very sensitive parameter,
irrespective whether the lesion affects the upper motor neurone, e.g. in cervical myelopathy, or the lower
motor neurone e.g. in cervical or lumbar radiculopathy. However, an increase of MEP latency alone does not
allow for a distinction of either upper motor neurone or lower motor neurone affection. We have therefore
scrutinized MEP latency and MEP waveform (amplitude, duration, and number of phases) in normal subjects,
as well as in patients with cervical myelopathy (upper motor neurone affection: UMNA) and in patients with
radiculopathies (lower motor neurone affection, LMNA). The increase of central motor latency compared to
normal values was significantly higher in UMNA than in LMNA. MEP following transcranial magnetoelectric
stimulation were split up and their duration in relation to M-wave duration was significantly increased in
patients with UMNA, yet normal in patients with LMNA. MEP amplitude in relation to M-wave amplitude was
significantly decreased in patients with UMNA, yet normal in patients with LMNA. We conclude that cervical
myelopathy and cervical or lumbar radiculopathies lead to changes of MEP waveform, which are specific for
either upper or LMNA. The analysis of amplitude, duration, and number of phases of MEP following

6. transcranial stimulation increases the diagnostic value of MEP in disorders of the spine affecting the central
or proximal peripheral motor pathways.
Palmer JB, Holloway AM, Tanaka E
Detecting lower motor neuron dysfunction of the pharynx and larynx with electromyography. [Journal
Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.]
Arch Phys Med Rehabil 1991 Mar; 72(3):214-8.
This study assessed the utility of clinical electromyography (EMG) for detecting lower motor neuron (LMN) or
upper motor neuron (UMN) dysfunction affecting the intrinsic muscles of the larynx and pharynx. Twenty-
nine subjects were examined; their clinical diagnoses included perioperative nerve injury, cerebral infarction,
and lateral medullary infarction. Resting activity, motor unit action potential (MUAP) morphology, and MUAP
recruitment were evaluated in every case. Medical records (excluding EMG data) were analyzed for clinical
evidence of LMN or UMN dysfunction in the intrinsic muscles of the larynx and pharynx. The diagnosis of
LMN dysfunction rested on clinical data consistent with cranial nerve injury, poliomyelitis, Wallenberg
syndrome, or unilateral bulbar palsy. Criteria for UMN dysfunction included previous cerebral (not
brainstem) infarction or mass lesion or the presence of hemiparesis. Electromyographic abnormalities were
significantly associated with LMN dysfunction (p less than .05), but they were not significantly associated
with UMN dysfunction. Of the parameters tested, MUAP recruitment was the most sensitive (82%) and
specific (92%).
Hömberg V, Stephan KM, Netz J
Transcranial stimulation of motor cortex in upper motor neurone syndrome: its relation to the motor deficit.
[Journal Article, Research Support, Non-U.S. Gov't]
Electroencephalogr Clin Neurophysiol 1991 Oct; 81(5):377-88.
The purpose of this investigation was to clarify the functional significance of the fastest cortico-
motoneuronal connections in chronic upper motor neurone syndromes. Using magneto-electrical stimulation
of motor cortex the intactness of cortico-motoneuronal connections was assessed in 51 patients presenting
with variable degrees of impairment. There was a gross correlation between clinical impairment of the
patient and the degree of pathology of cortico-motoneuronal efferents. Covariation of clinical data with
transcranial stimulation was better than covariation with the size of lesion on CT scans. In some patients,
however, definite clinical impairment, especially affecting distal fractionated movements, was associated
with completely normal responses. There was no evidence of response abnormality in distal muscles
ipsilateral to the hemispheric lesion. The data indicate that motor deficit can exist in the presence of normal
cortico-motoneuronal conduction times, showing that intactness of these connections is not a sufficient
condition for preservation of voluntary motor activities. This underlines the importance of other pathways for
the pathogenesis of upper motor neurone syndromes.
Swash M
Why are upper motor neuron signs difficult to elicit in amyotrophic lateral sclerosis? [Journal Article, Review]
J Neurol Neurosurg Psychiatry 2012 Jun; 83(6):659-62.
It is often difficult to identify signs of upper motor neuron lesion in the limbs of patients with amyotrophic
lateral sclerosis, in whom there is neurogenic muscle wasting of varying severity. The reasons for this are
complex and not related simply to the degree of lower motor neuron muscle wasting but, rather, depend on
the pathophysiological abnormalities that develop in response to damage to descending motor pathways and
to motor neurons and interneurons in the ventral horns of the spinal cord. The different mechanisms
underlying the clinical phenomenology of the functional motor defect in amyotrophic lateral sclerosis, that
lead to difficulty in detecting classical upper motor neuron signs, are discussed.
Noto Y, Kanai K, Misawa S, Shibuya K, Isose S, Nasu S, Sekiguchi Y, Fujimaki Y, Nakagawa M, Kuwabara S
Distal motor axonal dysfunction in amyotrophic lateral sclerosis. [Journal Article, Research Support, Non-
U.S. Gov't]
J Neurol Sci 2011 Mar 15; 302(1-2):58-62.

7. Nerve conduction slowing in amyotrophic lateral sclerosis (ALS) is usually caused by loss of fast motor
axons. We studied the frequency, extent, and distribution of prominently prolonged distal motor latencies in
ALS. We reviewed results of median, ulnar, and tibial nerve conduction studies in 91 patients with ALS, 24
with lower motor neuron disorders, and 36 with axonal neuropathy. Coincidental carpal tunnel syndrome
was found for 4 (4.4%) of the ALS patients who were excluded from analyses. Markedly prolonged distal
latencies (>125% of the upper limit of normal) were found only in the median nerve of ALS patients (9%),
and in none of the disease controls. Excitability studies suggested membrane depolarization in some ALS
patients. Our results show that approximately 10% of ALS patients shows prominently prolonged median
distal latency, which cannot be explained by axonal loss and carpal tunnel lesion. The distal nerve
conduction slowing may partly be caused by membrane depolarization possibly due to motor neuronal
degeneration in ALS. We suggest that recognition of the pattern of distal motor axonal dysfunction
predominant in the median nerve is clinically important, and could provide additional insights into the
pathophysiology of ALS.
Wagner G, Klinge H, Sachse MM
Ramsay Hunt syndrome. [Journal Article, Review]
J Dtsch Dermatol Ges 2012 Apr; 10(4):238-44.
Ramsay Hunt syndrome is defined as herpes zoster oticus associated with an acute peripheral facial nerve
paresis and quite often with other cranial nerve lesions. The combination of motor, sensory and autonomic
involvement leads to a variety of neurological damage patterns, i. e. facial muscle paresis, hearing and
balance disorders, sensory problems and disturbances of taste as well as lacrimal and nasal secretion.
Additional variability of the clinical picture of Ramsay Hunt syndrome is produced by varying patterns of skin
involvement explained by individual anastomoses between cranial and cervical nerves. Knowledge of these
findings and an early diagnosis of Ramsay Hunt syndrome are important as prognosis of cranial nerve
damage depends on the time at which acyclovir-corticosteroid therapy is started.
Ratnayake EC, Caldera M, Perera P, Gamage R
Isolated trigeminal nerve palsy with motor involvement as a presenting manifestation of multiple sclerosis in
an equatorial region - a case report. [Journal Article]
Int Arch Med 2012; 5(1):17.
ABSTRACT:Isolated cranial nerve palsies are considered to be an uncommon presenting feature of multiple
sclerosis. Involvement of the trigeminal nerve, particularly its motor component as part of a clinically
isolated syndrome of multiple sclerosis has rarely been reported in equatorial regions and no cases have
been described in Sri Lanka thus far.We report a case of isolated right sided trigeminal nerve palsy (Motor
and Sensory) in a 34 year old previously well lady from urban Sri Lanka who was found to have
characteristic lesions on Magnetic Resonance Imaging highly suggestive of multiple sclerosis.Multiple
sclerosis should be considered in the differential diagnosis of patients who present with isolated cranial
nerve palsies. Clinicians should have a high index of suspicion when evaluating such patients especially in
low prevalence regions close to the equator. Early recognition and treatment of such a "Clinically Isolated
Syndrome" may prevent early relapse.