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The medial plantar and medial peroneal cutaneous nerve conduction studies for diabetic polyneuropathy

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Objective of this study was to determine which nerve conduction is more sensitive electrophysiologically in the diagnosis of polyneuropathy in diabetics by evaluating the sensory conduction in medial plantar nerve and medial peroneal (dorsal) cutaneous nerves. Additionally to investigate the relation between Neuropathy Symptom Score (NSS) and Neuropathy Disability Score (NDS) values used in the diagnosis of these conduction studies. Forty patients with diagnosis diabetic neuropathy were included into this study. In diabetic polyneuropathic patient group, both medial plantar and medial dorsal cutaneous nerve sensory action potential were not bilaterally obtained in 19 patients (47.5%). Sensitivity and specificity of medial dorsal cutaneous nerve and medial plantar nerve sensory conduction abnormalities in diagnosis of diabetic polyneuropathy were higher compared to sural nerve conduction abnormalities. This study showed that both medial plantar and medial dorsal cutaneous nerve conduction study performed bilaterally was a highly sensitive and specific method in diagnosis of diabetic neuropathy.
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ORIGINAL ARTICLE
The medial plantar and medial peroneal cutaneous nerve
conduction studies for diabetic polyneuropathy
Yasar Altun Ahmet Demirkol Yener Tumay
Kazım Ekmekci Ibrahim Unsal
Ahmet Candan Koyluoglu Yasar Ozkul
Received: 14 January 2011 / Accepted: 14 June 2011
ÓSpringer-Verlag 2011
Abstract Objective of this study was to determine which
nerve conduction is more sensitive electrophysiologically
in the diagnosis of polyneuropathy in diabetics by evalu-
ating the sensory conduction in medial plantar nerve and
medial peroneal (dorsal) cutaneous nerves. Additionally to
investigate the relation between Neuropathy Symptom
Score (NSS) and Neuropathy Disability Score (NDS) val-
ues used in the diagnosis of these conduction studies. Forty
patients with diagnosis diabetic neuropathy were included
into this study. In diabetic polyneuropathic patient group,
both medial plantar and medial dorsal cutaneous nerve
sensory action potential were not bilaterally obtained in 19
patients (47.5%). Sensitivity and specificity of medial
dorsal cutaneous nerve and medial plantar nerve sensory
conduction abnormalities in diagnosis of diabetic poly-
neuropathy were higher compared to sural nerve conduc-
tion abnormalities. This study showed that both medial
plantar and medial dorsal cutaneous nerve conduction
study performed bilaterally was a highly sensitive and
specific method in diagnosis of diabetic neuropathy.
Keywords Diabetic polyneuropathy
Medial plantar nerve Medial dorsal cutaneous nerve
Neuropathy symptom score Neuropathy disability score
Introduction
Diabetic polyneuropathy is a common complication of DM
[1]. While the rate of polyneuropathy of the diabetic
patients in the first year from diagnosis of type 2 diabetes
was found to be 7%, clinical determination of polyneu-
ropathy increased to 50% as a consequence of 25 years
follow-up. Diabetic polyneuropathy was found to be more
than 60% by using electromyography (EMG) and the other
supplementary tests in addition to clinical examination [2].
The most distal sensory fibers of the feet are often affected
first in diabetic polyneuropathy. However, they are not
evaluated in routine sural, tibial, and superficial peroneal
nerve conduction studies (NCS). But NCS can be normal in
early phase of diabetes despite neuropathic complaint [3].
The medial plantar sensory nerve, which is a more distal
nerve than the sural nerve, is known to be more sensitive to
the detection of sensory neuropathy [4]. The medial dorsal
cutaneous nerve, the distal and medial branch of the
superficial peroneal, conveys sensory fibers to the medial
two-thirds of the dorsum of the foot. Conduction study of
these sensory nerves manifests in early phase of diabetic
polyneuropathy. But, sensitivity and specificity of medial
dorsal cutaneous nerve and medial plantar sensory nerve
conduction in diagnosis of diabetic polyneuropathy has not
been studied previously [5].
Therefore, we evaluated various nerves, including the
medial dorsal cutaneous nerve, and medial planter nerve in
patients with clinically diabetic polyneuropathy and in order
to assess their relative diagnostic usefulness in electro
diagnostic practice. We also aimed to identify the relation-
ship between Neuropathy Symptom Score (NSS) and Neu-
ropathy Disability Score (NDS) which are helpful tools for
the diagnosis of diabetic polyneuropathy with both the
medial plantar and medial dorsal cutaneous nerve study.
Y. Altun (&)Y. Tumay K. Ekmekci I. Unsal
A. C. Koyluoglu Y. Ozkul
Department of Neurology, Faculty of Medicine,
University of Harran, 63300 Sanliurfa, Turkey
e-mail: yasaraltun02@gmail.com
A. Demirkol
Department of Physical Medicine and Rehabilitation,
Faculty of Medicine, University of Harran, Sanliurfa, Turkey
123
Neurol Sci
DOI 10.1007/s10072-011-0669-2
Author's personal copy
Materials and method
Forty patients with diagnosis of type 2 DM and clinically
diabetic neuropathy who presented to electrophysiology
laboratory of neurology clinic for EMG between June 2008
and May 2009 were included into this study. Patients with
renal failure and other diseases which might cause
peripheral neuropathy and carpal tunnel syndrome, drug
use that would cause peripheral neuropathy and those
exposed to toxic substance were not included in the study.
Also, those above 65 years and under 30 years were
excluded in this study. Control group included healthy 30
volunteers without DM and neuropathic complaint. Our
study was approved by the local ethics committee.
Variables like gender, age, duration of disease, therapy
being received by the patient and fasting blood glucose
were used in clinical evaluation of the patient group.
Neuropathic symptoms of the patients were evaluated by
NSS [6]. Evaluation of neurological examination was
performed by NDS. NDS, muscle weakness are considered
to be best test available for evaluation of reflex and sensory
abnormalities [7]. Nihon Kohden EMG-EP V-08 device
was used in electrophysiological examination. Skin tem-
perature of the cases was maintained at 31–33°C. Ag/AgCl
disc superficial electrodes were used for records in con-
duction studies. Then conventional sensory and motor
conduction studies were performed in lower and upper
extremities. In NCS, motor latency was measured by taking
into consideration of starting point of negative deflection
and amplitude which was measured by taking into con-
sideration of peak points of negative and positive deflec-
tions. In motor nerve investigation, filter frequency was
arranged as 10 Hz–5 kHz, sweeping rate as 5 ms/div,
stimulus time 0.2 ms and stimulus frequency as 1/s. In
sensory nerve investigation, filter frequency was arranged
as 20 Hz–2 kHz, sweeping rate as 1 ms/div, stimulus time
0.2 ms and stimulus frequency as 1/s.
Motor NCS
1. In upper and lower extremities; comprehensive elec-
troneurography (ENG) and EMG were performed to
exclude trap neuropathies and radiculopathies. The
ones that could affect the results were not included in
the study.
2. Peroneal motor NCS: Compound muscle action
potential (CMAP) recordings from extensor digitorum
brevis muscle were performed by stimulating head of
wrist and fibula. Distal latency, conduction velocity,
CMAP amplitude was assessed in motor conduction
investigations. In addition to this, median and ulnar
nerve conductions were also assessed in upper
extremities; only in one extremity, median nerve was
included but ulnar nerve was not included in the study.
Sensory NCS
1. In upper extremities, median nerve sensory response
distal latencies and sensory nerve action potential
(SNAP)s were measured with recordings from wrist by
stimulus from palm.
2. In lower extremities;
(a) Both medial plantar nerves were stimulated by a pad
electrode at distal part of recorder electrode and
medial part of sole, between metatarsal bones toward
recorder electrode and recording was performed or-
todromically at medial malleolus over flexor retinac-
ulum. Nerve conduction velocity (NCV), distal
latency and amplitudes were measured (Fig. 1).
(b) Both medial dorsal cutaneous nerves were stimulated
by a pad electrode at distal part of recorder electrode
and medial part of sole between 1 and 2 metatarsal
bones toward recorder electrode. Recording was
performed orthodromically on 1/3 medial part of the
line joining medial and lateral malleoli (Fig. 2).
Additionally, distal latency and SNAP of this nerve
was measured. Reference value for medial plantar
NCV is 41.6 m/s, calculated on the basis of results
obtained in controls (mean ±2 SD). Reference value
for medial dorsal cutaneous NCV is 36.8 m/s, calcu-
lated on the basis of results obtained in controls
(mean ±2 SD).
Statistical analysis
During the evaluation of the data obtained from the study,
SPSS (Statistical Package for Social Sciences) Windows
11.5 and its programs were used for the statistical analysis.
The values with p\0.05 were considered to be statisti-
cally significant. Correlation analysis between non-para-
metric variables was performed by using Spearman’s rho
correlation test. During the evaluation of the study data,
regarding the comparisons of descriptive statistical meth-
ods (mean, standard deviation) and between data at con-
duction measurements, Mann–Whitney Utest, Pearson and
Spearman correlation tests were used. To determine the
sensitivity and specificity of medial plantar, medial dorsal
cutaneous, sural and peroneal conduction velocities in
diabetic patients, sensitivity [true positive/(true positi-
ve ?false negative)] and specificity [true negative/(true
negative ?false positive)] formulas were used.
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Results
Forty patients with DM (17 males, 23 females) and with
mean age of 53.52 ±6.44 years (min 34-maks 63 years)
and 30 healthy individuals with mean age of 49.53 ±
7.05 years (min 36-maks 64 years) were included in the
study There was no statistical significant difference between
groups regarding age and gender (p[0.05).
Duration of the disease of the patients with DM diagnosis
was 11.05 ±7.50 years. In 19 of the 40 patients with clinical
definite diabetic neuropathy, polyneuropathy diagnosis was
electrophysiologically supported with absence of both
medial plantar sensory and medial dorsal cutaneous sensory
response bilaterally (47.5%). Sural sensory nerve conduction
was normal in 10 (52.6%) of the 19 patients with abnormal
medial plantar sensory and medial dorsal cutaneous sensory
response. In diabetic patient group, sural SNAP was not
obtained in seven patients. Sural NCV was decreased in two
patients. Average sural nerve amplitude obtained from 33
patients was found 6.31 ±4.17 lV and average conduction
velocity was found 46.19 ±6.58 m/s. In diabetic patient
group, both medial plantar and medial dorsal cutaneous
SNAP was not obtained bilaterally in 19 patients. Also,
conduction velocities of these nerves were not calculated.
Apart from that, average medial plantar nerve amplitude and
conduction velocity obtained from 21 patients was found to
be 4.7 ±1.6 and 51.7 ±5.4, respectively, whereas average
medial dorsal cutaneous nerve amplitude and conduction
velocity was found to be 4.95 ±1.98 and 46.1 ±7.5 m/s,
respectively. In peroneal motor NCS, distal latency was
determined to be 4.58 ±1.12 ms, amplitude to be 4.47 ±
2.33 mV and conduction velocity to be 42.19 ±5.47 m/sn.
Comparison of patient and control group nerve conduction
was shown in Table 1.
Sensitivity and specificity of NCV of the diabetic
patients were shown in Table 2. Normal values of our
laboratory were obtained from the parameters recorded
prospectively from 30 healthy controls by using the same
technique. Abnormal values were calculated according to
±2 standard deviation from average values of these
parameters recorded from the controls (Table 2).
When the correlation between duration of disease and
NSS and NDS values was evaluated; a positive relation
was seen for both of two scores (respectively, p=0.027
and 0.026). A negative correlation was found between
duration of disease and medial dorsal cutaneous NCV
(p\0.05, r=-0.42), medial plantar NCV (p\0.05,
r=-0.40) and median SNAP amplitude (p=0.023,
r=-0.36). Average NSS of the patients was 3.80 ±1.04
and average NDS was 6.25 ±4.30. NSS and NDS values
were pathological in all of the patients. A correlation was
determined between medial plantar conduction velocity
Fig. 1 Medial plantar nerve
conduction technique and
medial plantar nerve SNAP
recording from a control subject
(Sstimulating electrode,
Rrecording electrode, Gground
electrode)
Fig. 2 Medial dorsal cutaneous
nerve conduction technique and
a ve medial dorsal cutaneous
nerve SNAP recording from a
control subject (Sstimulating
electrode, Rrecording electrode,
Gground electrode)
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(p=0.0001, r=-0.60), medial dorsal cutaneous action
potential amplitude (p=0.001, r=-0.49), peroneal
motor NCV (p=0.001, r=-0.49) peroneal motor nerve
distal latency (p=0.027, r=-0.35) and amplitude
(p=0.0001, r=-0.55), and median sensory NCV
(p=0.027, r=-0.35) with NDS. A negative correlation
was found between NSS and medial dorsal cutaneous NCV
(p=0.039, r=-0.33). A negative correlation was found
between NSS values of patients with and without medial
plantar response (p=0.0001, r=-0.64). Similarly, a
negative correlation was found between NDS values of
patients with and without dorsal cutaneous sensory con-
duction (p=0.0001, r=-0.64). In 47.5% of the diabetic
patients, electrophysiological response could not be
obtained from both of medial plantar and medial dorsal
cutaneous nerve.
Discussion
The main of this study was to investigate the clinical utility
of both medial plantar and medial dorsal cutaneous NCS in
the diagnosis of diabetic polyneuropathy. We have studied
a population of diabetics with clinical signs and symptoms
of polyneuropathy and compared them with healthy con-
trols. We found that both medial plantar and medial dorsal
cutaneous SNAPs could reliably be recorded in healthy
subjects under the 64 years of age. But, in patients with
clinically definite diabetic polyneuropathy these NCS were
significantly abnormal compared to the sural NCS.
Accurate diagnosis of polyneuropathy developing in
diabetic patients is possible with combined use of clinical
and electrophysiological tests. NCS are used as a sensitive,
objective, reliable and noninvasive method [7,8]. The sural
nerve has served as a traditional electrophysiological
marker of diabetic polyneuropathy, but up to two-third of
those tested with mild neuropathic symptoms may be
normal, emphasizing the need for more sensitive diagnostic
tests [3,9]. Hence, medial plantar and medial dorsal
cutaneous nerve NCS abnormality has been suggested in
the diagnosis of diabetic polyneuropathy [3,10]. Although
medial plantar and medial dorsal cutaneous nerves were
compared with NCS of the nerves located more proximally,
in diabetic polyneuropathy diagnosis, a study including
NCS investigating medial plantar and medial dorsal cuta-
neous nerves together was not performed before. Since
diabetic polyneuropathy begins from the most distal
nerves, conduction studies of medial plantar and dorsal
peroneal cutaneous sensory nerves can be helpful in diag-
nosis of diabetic polyneuropathy in the early period [3,10].
In this study, sensitivity and specificity of medial plantar
and medial dorsal cutaneous NCS in electrophysiological
diagnosis of the patients with clinical definite diabetic
polyneuropathy (abnormal NSS and NDS) was investi-
gated. A negative correlation was determined between
duration of disease and medial plantar and medial dorsal
cutaneous sensory NCV. In 47.5% of the diabetic patients
with neuropathy, a response could not be obtained from
both medial plantar and medial dorsal cutaneous nerves.
Table 1 Comparison of nerve conduction data belonging to patient
and control groups
Nerve Controls (n=30) Patient (n=40) pvalue
Medial plantar
Amplitude (lV) 10.70 ±5.46 4.7 ±1.6 0.000**
NCV (m/sn) 54.0 ±6.2 51.7 ±5.4 [0.05
No response (n) 0 19 0.000**
Medial dorsal cutaneous
Amplitude (lV) 4.60 ±1.93 4.95 ±1.98 [0.05
NCV (m/sn) 47.92 ±5.56 46.1 ±7.5 [0.05
No response (n) 0 19 0.000**
Peroneal motor
Latency (msn) 3.95 ±0.63 4.58 ±1.12 0.013*
Amplitude (mV) 7.81 ±3.15 4.47 ±2.33 0.000**
NCV (m/sn) 50.39 ±3.38 42.19 ±5.47 0.000**
Sural sensory
Amplitude (lV) 11.95 ±3.71 6.31 ±4.17 0.000**
NCV (m/sn) 52.06 ±5.66 46.19 ±6.58 0.000**
No response (n) 0 7 0.017
NCV nerve conduction velocity
*p\0.05, ** p\0.001 (Mann–Whitney U)
Table 2 Sensitivity and
specificity of nerve conduction
velocities in patients with
diabetic neuropathy (DN)
Abnormality
criteria
The number of
abnormality
in patients
with DN
Specificity
(%)
Sensitivity
(%)
Medial plantar conduction velocity (m/s) \41.6 19 47.5 96.6
Medial dorsal cutaneous conduction velocity
(m/s)
\36.8 19 47.5 100
Sural nerve conduction velocity (m/s) \40.6 15 37.5 93.3
Peroneal motor conduction velocity (m/s) \43.6 18 45 100
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Conduction velocities of responsible medial plantar and
medial dorsal cutaneous nerves in patients with diabetic
neuropathy were similar to the control group. However,
SNAP of responsible medial plantar nerve was found to be
markedly lower than control group. Previous studies rela-
ted with diabetic polyneuropathy, these NCS were shown
in Table 3[3,4,911]. In a study performed by An et al.
[4] medial plantar NCV and amplitude values in diabetic
patients were found to be significantly lower than control
group.In the study performed by Kushnir et al. [3] when
the amplitudes of medial dorsal cutaneous nerve were
compared with the control group, they were found to be
statistically significantly lower. In the study performed on
30 diabetic patients by Ulac et al. [10], bilateral response
could not be obtained from medial plantar nerve in 30% of
the patients. Besides that similar to our study, amplitude
values of medial plantar nerve in diabetic patients were
found to be significantly lower compared to the control
group. In our study, the rate of not obtaining response was
higher. The reason for not obtaining response from medial
plantar and medial dorsal cutaneous nerves in our study can
be because diabetic polyneuropathy affects the most distal
parts of the nerves in its earliest stages. Furthermore,
amplitude of SNAPs of lower extremities in individuals
over the age of 60 years decreases too much or cannot be
obtained. Discrimination of these findings from the chan-
ges due to the age in elderly patients with DM cannot be
always easy [2]. In our study, there was no patient over the
age 63 years. Obtaining medial plantar and medial dorsal
cutaneous nerve responses easily in healthy controls with
similar ages to diabetic patient group are evidence that this
condition is not technical. In addition to this, a marked
correlation was found NSS and NDS values of the patients
between responsible medial plantar and medial dorsal
cutaneous nerve. Although increasing age is a risk factor
for diabetic neuropathy, this rule is valid also for nerve
conduction changes in normal groups. In our study,
response was obtained from both medial plantar and medial
dorsal cutaneous nerves in all of control group younger
than 64 years of age and in 52.5% of diabetic patients.
In the study performed on 54 patients with chronic
sensorimotor polyneuropathy with normal sural conduction
by Kushnir et al., abnormal electrodiagnostic findings were
obtained from medial dorsal superficial nerve in more than
half of the patients. Similar to our study, they suggested
that medial dorsal superficial nerve conduction would
increase the diagnostic sensitivity and it should take place
among routine measurements even in the patients with mild
sensorimotor polyneuropathy [3]. In our study, polyneu-
ropathy was supported by NCS in 47.5% of clinical definite
diabetic neuropathy with patients. This rate is consistent
with literature [2]. In our study, sural NCS was normal in
approximately half of the patients with diabetic polyneu-
ropathy not obtaining medial dorsal cutaneous and medial
plantar response. This condition may reveal that not
obtaining medial plantar and medial dorsal cutaneous
response in the patients with clinical diabetic polyneurop-
athy is more valuable than sural nerve conduction in
electrophysiological diagnosis. Probably the most impor-
tant one among interesting findings of our study was
Table 3 Medial plantar and medial dorsal cutaneous nerve studies in diabetic neuropathy
Method Clinical features Finding
An et al. [4] Ortodromic medial
plantar NCS
Diabetic polyneuropathy
(n=82)
Abnormality of 46.7% in patients with symptomatic diabetic
neuropathy
Mean SNAP amplitude and NCV were significantly lower in
patients than in control
Kushnir et al. [3] Ortodromic medial
dorsal cutaneous NCS
Mild chronic sensorimotor
polyneuropathy (n=52)
Mean SNAP amplitude was significantly lower in patients than
in control
Ulac et al. [10] Ortodromic medial
plantar NCS
Diabetic DSN (n=30) Medial plantar SNAP amplitude was abnormal in 60% of the
patients bilaterally
30% patient’s medial plantar nerve bilateral response could not
be obtained
Løseth et al. [11] Ortodromic medial
plantar NCS
Diabetic DSN (n=50) Medial plantar nerve SNAP amplitudes were abnormal more
often than in the sural nerve. The medial plantar NCS were
abnormal in 59% of the cases
Sylantiev et al. [9] Ortodromic medial
plantar NCS
Distal symmetrical
polyneuropathy (n=85)
Sural and superficial peroneal nerve testing sensitivities were
about 55%, whereas medial plantar nerve testing sensitivity
was more than 90%
In this study Ortodromic medial
plantar and medial
dorsal cutaneous and
antidromic sural NCS
Diabetic DSN (n=40) We have shown that medial plantar conduction velocity
sensitivity (96.6%) specificity (47.5%) and medial dorsal
cutaneous conduction velocity sensitivity (100%) specificity
(47.5%)
NCS nerve conduction study, SNAP sensory nerve action potential, NCV nerve conduction velocity, DSN distal sensory neuropathy
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determination of sensitivity and specificity of medial
plantar and medial dorsal cutaneous nerve abnormality to
be higher than slowing in sural NCV in diabetic polyneu-
ropathy diagnosis. The highest sensitivity and specificity in
our patients with polyneuropathy was determined in medial
dorsal cutaneous nerve, medial plantar nerve, peroneal
motor conduction and sural nerve sensory conduction
abnormality. The amplitude and onset of electrophysio-
logical responses obtained from medial plantar nerve are
more evident than the electrophysiological responses
obtained from medial dorsal cutaneous nerve. This feature
helps the less experienced researchers to perform more
appropriate measurements. Besides that, since medial
plantar nerve begins to lose its functions in early period,
investigation of medial plantar nerve is a more sensitive
test [11]. In our opinion, the most important reason of early
damage is location of this nerve more distally compared to
medial dorsal cutaneous nerve. Furthermore, medial plan-
tar nerve which is located distally loses its functions much
faster by being exposed to microtrauma and pressure in
addition to impaired neuron metabolism due to diabetes.
More evident amplitude abnormality of medial plantar
nerve compared to medial dorsal cutaneous nerve ampli-
tude is an accurate sign of axonal involvement-related
disease, but it may arise from other factors without any
correlation with diabetes. These possible factors can be
enumerated as technical reasons, trapping under medial
tibial ligament (tarsal tunnel syndrome) and medial plantar
nerve lesion due to mechanic factors (like arthrosis and
fracture) [11]. There was no history of foot trauma and
malformation in any of the patients included in the study.
Regular wear and tear with walking and running and the
effect of tight shoes might provide low signal amplitudes,
but this effect was same in patient and control group [11].
Abnormality of unilateral medial plantar nerve and medial
dorsal cutaneous nerve is not sufficient to show the pres-
ence of distal sensory neuropathy [9,11]. Although it is a
rare condition, unilateral response cannot be obtained from
both of the nerves due to trapping of these nerves or more
frequently technical reasons. There was no response
bilaterally from both of medial plantar and medial dorsal
cutaneous nerves in 47.5% of the patients considered to
have diabetic neuropathy in our study. Although a response
could not be obtained bilaterally from both of medial
plantar and medial dorsal cutaneous nerves, sural NCV was
normal in approximately half of these patients with diabetic
polyneuropathy. Studying of bilaterally medial plantar and
medial dorsal cutaneous nerve conductions in routine tests
in addition to sural nerve conduction will increase the
detection rate of polyneuropathy in early period. Also,
medial plantar and medial dorsal cutaneous sensory NCS
may be helpful in the diagnosis of clinical diabetic poly-
neuropathy in symptomatic diabetic patients. And so,
medial plantar and medial dorsal cutaneous sensory NCS
should be performed when evaluating diabetic patients,
especially with normal sural NCS.
This study shows that sensitivity and specificity of not
obtaining a response in bilateral medial plantar and medial
dorsal cutaneous NCS is more evident than sural NCS.
Moreover, medial plantar and medial dorsal cutaneous
nerve conduction abnormalities between NSS and NDS in
the patients with diabetic polyneuropathy were found to be
correlated. These findings support that performing both
medial plantar and medial dorsal cutaneous NCS in addi-
tion to routine EMG studies will increase the sensitivity in
diagnosis of diabetic polyneuropathy.
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... Yöntemi kolaylaştırmak amacıyla gastroknemius kasını serbestleştirmek için ayak bileğinin hafif plantar fleksiyona getirilmesi sağlandı (Wainapel metodu) (7). Medial plantar sinir duyu iletisi; ayak tabanı medialinden ortodromik uyarılarak, 8-10 cm proksimalde, medial malleol arkasında fleksor retinakulum üzerinden kayıtlanarak yapıldı (Ponford metodu) (8). Medial dorsal (peroneal) kutanöz sinir duyusal iletisi; 1.ve 2. metatarsal kemik arasından ortodromik uyarılarak, 10 cm kadar proksimalde, ayak bileğinde; lateral ve medial malleol arası mesafenin 1/3 medialinden kayıtlandı (9). ...
... Kontrol grubunda medial dorsal kutanöz sinir latans, hız ve amplitüdleri Altun ve arkadaşlarının sonuçlarına benzerdir (8). Yeang ve arkadaşlarının yaptığı çalışmada amplitüdler yüksek bulunmuştur; ancak her ikisinde de medial dorsal kutanöz sinir antidromik çalışılmıştır (22). ...
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The Contribution of Saphenous, Superficial Peroneal, Medial Plantar and Medial Dorsal Cutaneous Nerve Conduction Studies in Diagnosis of Diabetic Neuropathy Aim: The aim of this study was to investigate the relation of the examination of saphenous, superficial peroneal, medial plantar and medial dorsal cutaneous nerve conduction with Diabetic Neuropathy and whether this examination may play a role in the early diagnosis of polyneuropathy or not. Material and Method: The population included 52 patients with diabetes mellitus, attended the department of neurology, and internal medicine clinics at GATA Haydarpaşa Training Hospital and 30 volunteers with no systemic disease. In addition to the routine nerve conduction study; saphenous, superficial peroneal, medial plantar and medial dorsal cutaneous nerve conduction studies were performed to all groups. Results: When the obtained data were evaluated, polyneuropathy, disease duration, and NSS (Neuropathy Symptom Scoring) in diabetic patients were found to be correlated with our results. Conclusion: By the electrophysiological evaluation of the diabetic patients with a clinical suspect of polyneuropathy even with sural nerve conduction study results within normal values, saphenous, superficial peroneal medial plantar and medial dorsal cutaneous nerve conduction should be added to the routine examination.
... They demonstrated that DS nerve may have been affected before pathology emerges in sural nerve [10]. Kökoğlu [13]. We neurophysiologically detected asymptomatic PNP in diabetic patients by studying nerve conduction properties of the three most distally located nerves (MP, DS, MDC) in addition to the classical nerve conduction studies in patients with newly diagnosed diabetes and without neurological symptoms. ...
... Previously we showed that the sensitivity and specificity of medial dorsal cutaneous nerve and medial plantar nerve sensory conduction abnormalities were higher in the diagnosis of diabetic polyneuropathy compared to sural nerve conduction abnormalities 29 . Thus, we examined distal end nerves assuming that distal end nerves were involved and damaged earlier than the sural nerve. ...
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Background and purpose: The purpose of this prospective study was to investigate whether mid-term treatment with oral isotretinoin may impact peripheral nerve function. Methods: In this study, we included 28 patients with no apparent neurological or neurophysiological findings. The patients received treatment with oral isotretinoin for papulopustular or nodulocystic acne. The patients with normal findings in the first examination were given 1 mg/kg/day oral isotretinoin. Neurological examinations and electroneurographic studies were performed before and 6 months after the onset of isotretinoin treatment. Results: Clinical examinations and electroneurographic evaluations prior to treatment revealed no abnormalities in any of the patients. However, 20 patients (72%) displayed one or more abnormal values in the tested parameters after treatment. Although the mean amplitudes of compound muscle action potential of the ulnar and median nerves did not vary, significant decreases were observed in the mean sensory conduction velocities of median, ulnar, sural, medial plantar, medial dorsal cutaneous, and dorsal sural nerves 6 months after the onset of treatment. Conclusion: Systemic use of isotretinoin may cause electroneurographic changes. Probable electroneurographic alterations may be detected at a much earlier period via dorsal sural nerve tracing when electrophysiological methods used in routine clinical practice cannot detect these changes.
... Sensory nerve action potentials (SNAPs) of the MPN are more sensitive than standard nerve testing in diagnosing peripheral neuropathy [53][54][55]. ...
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Medial plantar nerve (MPN) entrapment can be a cause of medial foot pain and possible sensory loss over the anteromedial sole. This nerve may be entrapped within the tarsal tunnel as a part of tarsal tunnel syndrome, at the entrance to the medial plantar tunnel under the abductor hallucis muscle, or at the knot of Henry. Treatment of the perpetuating factors like hyperpronation and inappropriate footwear, along with medication and injections, can lead to improvement of symptoms.
... Therefore, early discovery and diagnosis are extremely important. Nerve conduction studies are the most common method for diagnosis of peripheral neuropathy Kincaid et al., 2007;Koçer et al., 2007;Severinsen and Andersen, 2007;Kiziltan and Benbir, 2008;Løseth et al., 2008Løseth et al., , 2010Uluc et al., 2008;Asad et al., 2009;Hemmi et al., 2009;Watanabe et al., 2009;Charles et al., 2010;Dyck et al., 2010;Lee et al., 2010;Suh et al., 2010;Watanabe et al., 2010;Altun et al., 2011;Dyck et al., 2011;Koytak et al., 2011;Shin et al., 2011;Heise et al., 2012;Mondal et al., 2012;Morimoto et al., 2012;Spadella et al., 2012;Arimura et al., 2013;Joa and Kim, 2013;Koo et al., 2013;Richardson et al., 2013;Chiles et al., 2014;McLellan et al., 2014). Heise et al. (2012) found that the combined in-dex, comprising five parameters of nerve conduction, had greater sensitivity and equivalent specificity compared with individual parameters in the detection of diabetic polyneuropathy. ...
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Early diagnosis of diabetic peripheral neuropathy is important for the successful treatment of diabetes mellitus. In the present study, we recruited 500 diabetic patients from the Fourth Affiliated Hospital of Kunming Medical University in China from June 2008 to September 2013: 221 cases showed symptoms of peripheral neuropathy (symptomatic group) and 279 cases had no symptoms of peripheral impairment (asymptomatic group). One hundred healthy control subjects were also recruited. Nerve conduction studies revealed that distal motor latency was longer, sensory nerve conduction velocity was slower, and sensory nerve action potential and amplitude of compound muscle action potential were significantly lower in the median, ulnar, posterior tibial and common peroneal nerve in the diabetic groups compared with control subjects. Moreover, the alterations were more obvious in patients with symptoms of peripheral neuropathy. Of the 500 diabetic patients, neural conduction abnormalities were detected in 358 cases (71.6%), among which impairment of the common peroneal nerve was most prominent. Sensory nerve abnormality was more obvious than motor nerve abnormality in the diabetic groups. The amplitude of sensory nerve action potential was the most sensitive measure of peripheral neuropathy. Our results reveal that varying degrees of nerve conduction changes are present in the early, asymptomatic stage of diabetic peripheral neuropathy.
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Background: Diabetic foot ulcer, one of the frequent in addition to severe complication of diabetes about 12-25% people has risk of developing diabetes. Diabetic foot ulceration can be identified as a very well-demarcated full thickness injury at distal part of the ankle. Aim: The aim of the current study was to explore whether medial plantar nerve conduction velocity and lateral plantar nerve conduction velocity can predict the diabetic foot among diabetic population. Materials and Methods: 50 subjects diagnosed with diabetic mellitus type-2 were recruited based on inclusion and exclusion criteria. Subjects were explained about the NCV. Medial plantar and lateral plantar nerve, both side CMAP (Compound motor action potential) and SNAP (Sensory nerve action potential) were documented. Results: Results showed that the subjects were having normal conduction in motor NCV in both male and female. There was decrease in root mean square value of sensory NCV of 39.69=M, 38.66=F, lateral plantar sensory nerve left side, showed decrease in the conduction velocity though it was not statistically significant change. Conclusion: Motor conduction and Sensory conduction velocity of Medial plantar and Lateral plantar nerve could not predict the diabetic foot among diabetic population. There is no significant changes in Medial plantar nerve motor and sensory conduction velocity but left side lateral plantar sensory nerve conduction showed some changes in SNAP though it was not statistically significant change. Keywords: Diabetic mellitus type-2, diabetic foot, NCV, lateral plantar nerve, medial plantar nerve, CMAP, SNAP.
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Purpose: The purpose of this prospective 3-year follow-up was to investigate the association of glucose, insulin, and cholesterol levels with peripheral nervous system function in overweight and obese subjects. Methods: Forty nondiabetic overweight and obese adults were enrolled, of whom 29 completed the follow-up. Peripheral nervous system function was measured and defined by conduction studies of the peroneal motor nerve and the radial, sural, and medial plantar sensory nerves. Serum insulin and glucose levels were determined with an oral glucose tolerance test, and cholesterol levels were measured. The measurements were performed at baseline and after 3 years. Results: The change in serum insulin level at 120 minutes after an oral glucose tolerance test was positively associated with changes in peroneal nerve conduction velocities and F-wave mean, sural nerve conduction and medial plantar nerve conduction velocities. Action potential amplitudes decreased consistently and significantly in all sensory nerves. Conclusions: The change in serum insulin level at 120 minutes appears to be positively associated with changes in nerve conduction velocities more than 3 years but not with nerve action potential amplitudes. Significant decreases in the action potential amplitudes of all sensory nerves suggest that such changes might be the earliest detectable sign of damage to the peripheral nervous system in overweight and obese people without type 2 diabetes.
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Objective The electrodiagnosis of polyneuropathy (PNP) may benefit from examination using near-nerve needle technique (NNT) and from inclusion of distal nerves. This study compared the diagnostic utility of distal nerve conduction studies (NCS) and NNT recording. Methods Bilateral NNT and surface recording of the sural nerve and surface recording of the dorsal sural and medial plantar nerves were prospectively done in 91 patients with clinically suspected PNP. Distal NCS were additionally done in 37 healthy controls. Diagnostic reference standard was the final clinical diagnosis retrieved from the patients medical records after 1-4 years. Results The clinical follow-up diagnosis confirmed PNP in 68 patients. Equally high sensitivities of the dorsal sural (72%), medial plantar (75%), and sural nerve with NNT recording (77%) were seen, while the sensitivity of conventional surface recording of the sural nerve was lower (60%). Sural NCS with both NNT and surface recording and dorsal sural NCS showed high specificities (85-95%) and positive predictive values (94-98%), while a lower specificity was seen for the medial plantar nerve (68%). Conclusion NCS of distal nerves, especially the dorsal sural nerve, have high diagnostic power equalling sural NNT recording. Significance The electrodiagnostic evaluation of patients with suspected PNP benefits from NCS of distal nerves.
Article
Different nerve fibers may have disparate conduction parameters even though they are in the same peripheral nerve. Hyperglycemia can have differential effects on nerve fibers, depending on diameter. In diabetes, conventional nerve conduction studies have allowed us to classify a peripheral nerve as normal or not. But, there may be differential involvement in disparate nerve fibers of the same peripheral nerve. This study evaluated the effects of hyperglycemia on nerve fibers of peroneal nerve by diameter. Thirty-five diabetic patients with normal nerve conduction studies and thirty-two healthy controls were included to the study. The peroneal nerve was stimulated from two points (upper and below the fibula head) and recorded from the tibialis anterior (TA) and extensor digitorum brevis (EDB) muscles. Then the ratios of conduction velocity parameters recorded in these sides were compared between the diabetic and control groups. The conduction velocity recorded from EDB seemed to be faster in both groups. But there were no significant differences among the ratios between the groups. Our study has demonstrated the conduction parameters of two nerve fibers with different diameters in the peroneal nerve. The ratios of conduction parameters were similar in both groups, suggesting that fibers in the peroneal nerve are similarly affected by hyperglycemia.
Article
Objectives: Prediabetes includes individuals with impaired glucose metabolism, and it has been associated with various complications of diabetes mellitus (DM), including peripheral neuropathy. We aimed to investigate the associations between pro-inflammatory (TNF-α) and anti-inflammatory (IL-10) cytokines and neuropathy of very distal sensory nerves in patients with prediabetes or type 2 DM. Materials and methods: We included 50 patients with prediabetes, 50 patients with type 2 DM, and 44 controls in the study. Plasma levels of HbA1c, TNF-α, and IL-10 were analyzed. Electrodiagnostic testing was performed on dorsal sural and medial plantar sensory nerves, which are the very distal sensory nerves of the feet. Results: Abnormalities in nerve conduction studies (NCS) of the dorsal sural and medial plantar sensory nerves were substantially higher in patients with prediabetes or type 2 DM. In addition, plasma levels of TNF-α were significantly higher in patients with type 2 DM than in controls, whereas IL-10 levels were significantly lower in patients with both prediabetes and diabetes. However, we found no correlation between the levels of HbA1c, TNF-α, IL-10, and abnormalities in NCS of the dorsal sural or medial plantar sensory nerves in either patient group. Conclusions: To our knowledge, this is the first study to assess the relationships between TNF-α, IL-10, and NCS of the most distal sensory nerves in patients with prediabetes or type 2 DM. The mechanisms involved in the pathogenesis of DM and diabetic peripheral neuropathy are complex. The pro-inflammatory stage and the high incidence of neuropathy in patients with prediabetes may suggest a possible causative effect; however, the potential role of inflammation in the pathogenesis of peripheral neuropathy needs further clarification.
Article
The superficial peroneal nerve subserves sensation on the entire surface of the dorsum of the foot, except in small areas. All previously reported techniques for evaluating nerve conduction along this nerve tested a proximal portion of the nerve. We report a new method for evaluating sensory nerve conduction of the four branches of the distal superficial peroneal nerve. Two branches to the second and third toes of the medial dorsal cutaneous nerve and two branches to the fourth and fifth toes of the intermediate dorsal cutaneous nerve were studied orthodromically and antidromically in 37 feet of 21 normal volunteers using surface stimulating and recording electrodes and with a distance of 10 cm between the stimulating and recording electrodes. Maximum nerve conduction velocities (NCV) ranged from 41.8 to 46.9 m/s, and mean response amplitude ranged from 6.5 to 7.6 μV with the orthodromic technique. Values for NCV were almost identical when elicited by antidromic and orthodromic techniques, but response amplitudes were higher with the antidromic technique. Mean amplitudes of the distal superficial peroneal nerve were about 50% of the proximal superficial peroneal, and the conduction velocity in the distal superficial peroneal was slower than that in the proximal superficial peroneal nerve, by 8–14 m/s. In seven cases, distal superficial peroneal neuropathy was confirmed with this technique: two with proper digital neuropathy, two with medial dorsal cutaneous neuropathy, and three with intermediate dorsal cutaneous neuropathy. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 689–694, 2001
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Diabetic peripheral neuropathies are a group of heterogeneous syndromes with considerable morbidity. At least 50% of diabetic patients develop one or several of these neuropathies within 25 years after the diagnosis. In recent years several pathogenetic mechanisms have been proposed, with the newest findings suggesting a link between several of these hypotheses. The hypoxic hypothesis has revived the role of vascular factors in the pathogenesis of diabetic peripheral neuropathies. Although the exact role of hyperglycemia in the development of peripheral neuropathy is not known, the balance of evidence indicates that attainment and maintenance of normal blood glucose remains the cornerstone of treatment of diabetes and diabetic neuropathies. There is no convincing evidence that any of the treatments devised to correct the metabolic derangements in nerve are of sufficient value or safety to be recommended for routine use.
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Enhanced production of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) in diabetes leads to degradation of extracellular matrix in blood vessels and leads to complications of diabetes. In the present study, we have targeted MMP-2 and MMP-9 overactivation in diabetic neuropathy using a known MMP-2 and MMP-9 inhibitor, minocycline, with a non-selective COX inhibitor, aspirin. Streptozotocin-induced diabetic neuropathy was carried out in male Wistar rats and monitored by measuring the sensory nerve conduction velocity (SNCV), motor nerve conduction velocity (MNCV), tail flick latency and hot plate latency. Three weeks of treatment with a combination of minocycline and aspirin showed significant improvement in SNCV, MNCV, hot plate latency and tail flick latency when compared with diabetic control. The results of the present study suggest that MMP-2 and MMP-9 inhibition in the presence of COX inhibitor prevents the development of experimental diabetic neuropathy in rats and can be a potential approach for the treatment.
Article
Many studies have used sural nerve action potential (NAP) as an electrophysiological marker for distal symmetrical polyneuropathy (DSP). We examined the role of medial plantar nerve testing for identifying DSP by comparing amplitudes from sural, superficial peroneal, and medial plantar nerves in 85 participants with symptoms and clinical signs of DSP and 204 participants without DSP. Receiver-operating characteristic curves were used to determine the sensitivity of all three sensory conduction studies for the diagnosis of DSP. All three nerves could be used to discriminate between subjects with and without DSP with an area under the curve of more than 85% of cases. Sural and superficial peroneal nerve testing sensitivities were about 55%, whereas medial plantar nerve testing sensitivity was more than 90%. These findings suggest that testing the medial plantar nerve may increase the diagnostic yield of nerve conduction studies for DSP.
Article
We report a case of Guillain-Barré syndrome (GBS) accompanied by optic neuritis and a central white matter lesion subsequent to Epstein-Barr virus (EBV) infection. A 49-year-old man presented with visual disturbance and hemiparesis one week after developing cold-like symptoms. T2- and diffusion-weighted brain MRI showed a high-signal intensity lesion in the left internal capsule. The patient's visual acuity improved during steroid pulse therapy, but his hemiparesis progressed to quadriparesis. Nerve conduction studies showed demyelination predominant in the distal nerve terminals, consistent with GBS. Serological testing suggested EBV reinfection. Our findings indicate that EBV-related central and peripheral demyelination can occur simultaneously and can be successfully treated with a combination of corticosteroids and immunoglobulin.
Article
Diabetic Neuropathy Symptom (DNS) scoring and medial plantar NCS are useful methods for diagnosis of diabetic polyneuropathy (DPN). We evaluated the correlation between DNS score and medial plantar NCS in diabetic patients with a normal routine NCS. Nineteen healthy subjects were included as a control group. Fifty patients with diabetes mellitus who were referred for the evaluation of DPN were recruited (35 asymptomatic and 15 symptomatic). Control subjects and diabetic patients over the age of 70 were excluded from this study. Medial plantar nerve action potential (NAP) was recordable in all 19 control subjects and was not obtainable in 7 out of 15 symptomatic patients and in 5 out of 35 asymptomatic patients. The amplitudes of sural (Spearman r=-0.293, p=0.003) and medial plantar NAP (Spearman r=-0.215, p=0.03) correlated with DNS score. An abnormality finding in the medial plantar sensory nerve conduction study is a more sensitive indicator than sural nerve conduction study in the diagnosis of DPN and the medial plantar sensory nerve should be included in the evaluation of DPN in patients showing normal routine NCS.
Article
The reported prevalence of diabetic polyneuropathy varies from 5 to 80%. This unsatisfactory state may relate to evaluation of different patient groups, different minimal criteria for the diagnosis of neuropathy, and different degrees of surveillance. To made matters worse, patients with polyneuropathy tend to be equated ignoring differences in severity. To remedy this situation, four recommendations are made: (1) population-based patients should be studied, (2) nerve conduction should be used to set minimal criteria for neuropathy because the test is objective, sensitive, and repeatable, (3) validated tests of symptoms and deficits should also be used because clinical manifestations of neuropathy cannot be accurately inferred from electrophysiologic measurements, and (4) approaches to staging severity of neuropathy should be developed and used in expressing abnormality. To this end minimal criteria for the diagnosis of diabetic polyneuropathy have been proposed, and validated tests to assess neuropathic symptoms and sensory deficits have been developed. In this report we also propose a staging approach utilizing nerve conduction and neurologic history and examination and validated tests of neuropathic symptoms and deficits.
Article
In this study we examined the diagnostic sensitivity of minimal F-wave latency, F-wave persistence, motor nerve conduction velocity (MCV), and amplitude of the compound motor action potential (CMAP) of the median, ulnar, tibial, and peroneal nerves, and of sensory conduction velocity (SCV) and sensory nerve action potential (SNAP) amplitude of the sural nerve in 82 diabetic patients. For the median, ulnar, and tibial nerves the Z scores of the minimal F-wave latency were significantly larger than those of the MCV, and for all four motor nerves the Z scores of the minimal F-wave latency were significantly larger than those of the amplitude of the CMAP. The Z scores of the peroneal minimal F-wave latency exceeded those of peroneal MCV, sural SCV, and sural SNAP. F-wave persistence did not differ significantly from the reference values. In conclusion, minimal F-wave latency is the most sensitive measure for detection of nerve pathology and should be considered in electrophysiological studies of diabetic patients.
Article
We studied medial dorsal superficial peroneal (MDSP) nerves in 52 patients with clinical evidence of mild chronic sensorimotor polyneuropathy and normal sural nerve responses, in order to assess the diagnostic sensitivity and usefulness of MDSP nerve testing in electrodiagnostic practice. To determine the effect of age on MDSP nerve parameters, 98 normal subjects were also examined. Electrodiagnostic evaluation involved studies of motor nerve conduction in tibial, peroneal, and median nerves; sensory nerve conduction in sural, MDSP, median, and radial nerves; tibial and peroneal nerve F waves; H reflexes from the soleus muscles; and needle electromyography of gastrocnemius and abductor hallucis muscles. Among the patients, 49% had low-amplitude sensory responses in MDSP nerves and 57% had either slowing of sensory conduction velocity or no sensory responses on proximal stimulation. MDSP nerve amplitude, tibial nerve motor velocity, and H reflexes were the most sensitive for detection of mild chronic symmetrical axonal sensorimotor polyneuropathy. MDSP nerve testing should be included in the routine electrodiagnostic evaluation of patients with suspected polyneuropathy and normal sural nerve responses.
Article
To collect a reference material of the medial plantar nerve action potential, to test intra/interobserver reliability in healthy controls and to apply the test to a group of patients with diabetes mellitus. 98 healthy controls and 50 patients with diabetes mellitus were included. The medial plantar nerve was stimulated orthodromically and recorded with a surface electrode. In the patient group, NCS of motor and sensory nerves and quantitative sensory testing were also performed. Responses of the medial plantar nerve were obtained from all controls except from one aged 72. Amplitude decreased with age (r=-0.68, p<0.0001). Intra/interobserver reliability was acceptable. 52% of the patients had abnormal overall NCS classification. Forty-eight percent had delayed tibial F-response latency. The medial plantar NCS were abnormal in 59% of the cases (47% abnormal NAP amplitude and 39% reduced CV), 59% of those with abnormal NCS had symptoms of sensory polyneuropathy. Only 24% had abnormal sural amplitude. Cold perception threshold was abnormal in more patients (30%) than warmth perception threshold (14%). Responses were easily obtained in controls under 70 years. In diabetics the amplitudes of the medial plantar nerve were abnormal more often than in the sural nerve. The medial plantar nerve response is reliable in patients under 70 years, and intra/interobserver reliability is acceptable.