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Established in April 2006 Monthly Total No.3 Volume1 Number 3 25th June 2006
Publisher：JiangLLGJB Publish Time：Tuesday, December 09, 2008
Source：Neural Regen Res 2006;1(3):253－２５5
Effect of low-frequency pulse percutaneous electric stimulation on peripheral nerve injuries at
different sites
Jinwu Wang1, Liye Chen2, Qi Li1, Weifeng Ni1, Min Zhang3, Shangchun Guo1, Bingfang Zeng1
1Department of Orthopaedics,Sixth People's Hospital of Shanghai Jiaotong University, Shanghai
200233, China
2Shanghai Teresa Healthcare Sci Tech Co., Ltd., Shanghai 200233, China
3Department of Electroneuromyography, Sixth People's Hospital of Shanghai Jiaotong University,
Shanghai 200233, China
Jinwu Wang, Doctor, Associate professor, Department of Orthopaedics, Sixth People's Hospital of
Shanghai Jiaotong University, Shanghai 200233, China
Supported by: grants from Scientific Research Fund of the Ministry of Health, No. 20040801; Shanghai
Rising-Star Program of Technological Committee, No. 05QMX1438
Wang JW, Chen LY, Li Q, Ni WF, Zhang M, Guo SC, Zeng BF.Effect of low-frequency pulse
percutaneous electric stimulation on peripheral nerve injuries at different sites.Neural Regen Res
2006;1(3):253－２５5
www.sjzsyj.com/Journal/0603/06-03-253.html
Received:2006-05-02;Accepted:2006-06-08
(06-S-07-1018/LXQ)
Corresponding author:Jinwu Wang, Department of Orthopaedics,Sixth People's Hospital of
Shanghai Jiaotong University, Shanghai 200233, China E-mail: jinwu_wang@sohu.com
Abstract
BACKGROUND: The postoperative recovery of nerve function in patients with peripheral nerve injury
is always an important problem to solve after treatment. The electric stimulation induced
electromagnetic field can nourish nerve, postpone muscular atrophy, and help the postoperative
neuromuscular function.
OBJECTIVE: To observe the effects of low-frequency pulse percutaneous electric stimulation on the
functional recovery of postoperative patients with peripheral nerve injury, and quantitatively evaluate the
results of electromyogram (EMG) examination before and after treatment.
DESIGN: A retrospective case analysis.
SETTING: The Sixth People's Hospital affiliated to Shanghai Jiaotong University.
PARTICIPANTS: Nineteen postoperative inpatients with peripheral nerve injury were selected from
the Department of Orthopaedics, the Sixth People's Hospital affiliated to Shanghai Jiaotong University
from June 2005 to January 2006, including 13 males and 6 females aged 24-62 years with an average of
36 years old. There were 3 cases of brachial plexus nerve injury, 3 of median nerve injury, 7 of radial
nerve injury, 3 of ulnar nerve injury and 3 of common peroneal nerve injury, and all the patients received
probing nerve fiber restoration. Their main preoperative manifestations were dennervation, pain in limbs,
motor and sensory disturbances. All the 19 patients were informed with the therapeutic program and
items for evaluation.
METHODS: ① Low-frequency pulse percutaneous electric stimulation apparatus: The patients were
given electric stimulation with the TERESA cantata instrument (TERESA-0, Shanghai Teresa Health
Technology, Co.,Ltd.). The patients were stimulated with symmetric square waves of 1-111 Hz, and the
intensity was 1.2-5.0 mA, and it was gradually adjusted according to the recovered conditions of neural
regeneration following the principle that the intensity was strong enough and the patients felt no obvious
upset. They were treated for 4-24 weeks, 10-30 minutes for each time, 1-3 times a day, and 6 weeks as a
course. ② EMG examination was applied to evaluate the recoveries of recruitment, motor conduction
velocity (MCV) and sensory conduction velocity (SCV) before and after treatment. The patients were
examined with the EMG apparatus (DISA2000C, Danmark) before and after the treatment of
percutaneous electric stimulation. ③ Standards for evaluating the effects included cured (complete
recovery of motor functions, muscle strength of grade 5, no abnormality in EMG examination),
obviously effective [general recovery of motor function, muscle strength of grade 4, no or a few
denervation potentials, motor conduction velocity (MCV) and sensory conduction velocity (SCV)],
improved (partial recovery of motor function, muscle strength of grade 3, denervation potentials and
reinneration potentials, slowed MCV and SCV, invalid (no obvious changes of motor function).
MAIN OUTCOME MEASURES: ① Ameliorated degree of the nerve function of the postoperative
patients with peripheral nerve injury treated with percutaneous electric stimulation; ② Changes of EMG
examination before and after treatment.
RESULTS: All the 19 postoperative patients with peripheral nerve injury were involved in the analysis
of results. ① Comparison of nerve function before and after treatment in 19 patients with peripheral
nerve injury of different sites: For the patients with radial nerve injury (n=7), the nerve functions all
completely recovered after 8-week treatment, and the cured and obvious rate was 100% (7/7); For the
patients with brachial plexus nerve injury (n=3), 1 case had no obvious improvement, and the cured and
obvious rate was 67% (2/3); For the patients with common peroneal nerve injury (n=3), the extension of
foot dorsum generally recovered in 1 case of nerve contusion after 4-week treatment, and the cured and
obvious rate was 67% (2/3); For the patients with median nerve injury (n=3), muscle strength was
obviously recovered, and the cured and obvious rate was 100% (3/3); For the patients with ulnar nerve
injury (n=3), 1 case only had recovery of partial senses, and the cured and obvious rate was 67% (2/3).
Totally 9 cases were cured, 7 were obviously effective, 1 was improved, and only 2 were invalid. After 4
courses, the cured rate of damaged nerve function after four courses was 47% (9/19), and effective rate
was 89% (17/19). ② Comparison of EMG examination before and after treatment: Before and after
percutaneous electric stimulation, he effective rates of recruitment, MCV and SCV were 89% (17/19),
58% (11/19), 47% (9/19) respectively, and there were extremely obvious differences (P < 0.01).
CONCLUSION: ① Low-frequency pulse percutaneous electric stimulation can improve the nerve
function of postoperative patients with peripheral nerve injury of different sites, especially that the
injuries of radial nerve and median nerve recover more obviously. ②Percutaneous electric stimulation
can ameliorate the indexes of EMG examination, especially the recruitment, in postoperative patients
with peripheral nerve injury.
INTRODUCTION
At present, the complete recovery of nerve function after peripheral nerve injury is still a clinical
difficulty[1]. The recovery of nerve usually takes a long time after the operation for peripheral nerve
injury, and the final therapeutic effects are affected by the lack of effective rehabilitative measures or
restriction of condition postoperatively[2]. This study observed the effects of low-frequency pulse
percutaneous electric stimulation on postoperative neural regeneration and the functional recovery in
peripheral nerve injury.
SUBJECTS AND METHODS
Subjects
Nineteen postoperative inpatients with peripheral nerve injury were selected from the Department of
Orthopaedics, the Sixth People's Hospital affiliated to Shanghai Jiaotong University from June 2005 to
January 2006, including 13 males and 6 females aged 24-62 years with an average of 36 years old, and
they were all informed with the therapeutic program and items for evaluatation. There were 3 cases of
brachial plexus nerve injury, 3 of median nerve injury, 7 of radial nerve injury, 3 of ulnar nerve injury
and 3 of common peroneal nerve injury, and all the patients received probing nerve fiber restoration.
Their main preoperative manifestations were dennervation, pain in limbs, motor and sensory
disturbances.
Methods
Treatment of low-frequency pulse percutaneous electric stimulation
The patients were given electric stimulation with the TERESA cantata instrument (TERESA-0, Shanghai
Teresa Health Technology, Co.,Ltd.). The skin electrodes were stuck to the motor point and the distal
damaged nerve or the projection on the body surface of the damaged nerve, so that the electrodes could
get close to the nerve as much as possible. The patients were stimulated with symmetric square waves of
1-111 Hz, and the intensity was 1.2-5.0 mA, and it was gradually adjusted according to the recovered
conditions of neural regeneration following the principle that the intensity was strong enough and the
patients felt no obvious upset. They were treated for 4-24 weeks, 10-30 minutes for each time, 1-3 times
a day, and 6 weeks as a course.
Electromyogram (EMG) examination
The patients were examined with the EMG apparatus (DISA2000C, Danmark) before and after the
treatment of percutaneous electric stimulation. The recoveries of recruitment, motor conduction velocity
(MCV) and sensory conduction velocity (SCV) were compared before and after treatment.
Standards for evaluating the effects
Cured: The functions of upper limbs and hands completely recovered, muscle strength was grade 5,
numbness and pain disappeared, EMG had no abnormality, MCV and SCV recovered to normal.
Obviously effective: Motor function generally recovered, muscle strength was grade 4, no obvious
numbness and abnormal algesia, EMG showed no or a few denervation potentials, reinneration potential
could be observed, the motor units appeared mixed phase, MCV and SCV were generally normal.
Improved: Motor function partially recovered, muscle strength was grade 3, numbness and algesia were
alleviated, EMG showed denervation potentials and reinneration potentials, the motor units were reduced
and appeared monophase and mixed phase, MCV and SCV were slowed down. Invalid: Motor function
had no obvious changes before and after treatment.
Statistical analysis
The data were processed with SPSS 10.0 software by the second author, and the enumeration data were
analyzed with the chi-square test.
RESULTS
Quantitative analysis of the participants
All the 19 postoperative patients with peripheral nerve injury were involved in the analysis of results.
Comparison of the therapeutic effects of percutaneous electric stimulation in the 19 patients with
peripheral nerve injury (Table 1)
All the 19 postoperative patients with peripheral nerve injury had manifestations of nerve recovery to
different extent after treatment of 1 or 2 courses. ① For the patients with radial nerve injury (n=7), the
muscle strength of 5 cases recovered from grade 0 to grade 5 after 8-week treatment averagely, and the
cured and obvious rate was 100% (7/7). ② For the patients with brachial plexus nerve injury (n=3), 1
case had no obvious improvement, and the nerve function of the other 2 cases recovered generally, and
the cured and obvious rate was 67% (2/3). ③ For the patients with common peroneal nerve injury (n=3),
the sensory functions were all obviously improved after treatment of 1 course, including the extension of
foot dorsum generally recovered in 1 case of nerve contusion after 4-week treatment, and the cured and
obvious rate was 67% (2/3). ④ For the patients with median nerve injury (n=3), muscle strength was
obviously recovered, and the cured and obvious rate was 100% (3/3). ⑤ For the patients with ulnar
nerve injury (n=3), 1 case only had recovery of partial senses, and the muscle strength was generally
recovered in the other 2 cases, and the cured and obvious rate was 67% (2/3). The muscular atrophy was
obviously improved in all the patients after electric stimulation.
For the 19 postoperative patients with peripheral nerve injury after percutaneous nerve injury, 9 cases
were cured, 7 were obviously effective, 1 was improved, and only 2 were invalid. After 4 courses, the
cured rate was 47% (9/19), and effective rate was 89% (17/19).
Comparison of EMG examination before and after percutaneous electric stimulation in the 19
postoperative patients with peripheral nerve injury (Table 2)
The indexes of EMG examination before and after percutaneous electric stimulation were extremely
different (P < 0.01). The effective rates of recruitment, MCV and SCV were 89% (17/19), 58% (11/19),
47% (9/19) respectively.
DISCUSSION
The effect of electric stimulation on neural regeneration has attracted the attentions and been
recognized by many scholars[3,4]. Plenty of studies have confirmed that nerve growth obviously trends
to negative electrode, the electric stimulation induced electromagnetic field can nourish nerve, promote
the orientation of local Ca2+ to nerve growth, and can accelerate the velocity of neural axon to pass
through the site of neuromata-like injury, promote the proliferation of neurilemma theca cells, the
reformation of myelin sheath, and the passive movement of muscle, and increase the establishment of
the effective relationship between axon of movement and effector of muscle[5,6]. We have observed
clinically that the sensory disorder and muscle strength are ameliorated in a shorter period after
treatment of electric stimulation, which suggested that electric stimulation can increase the
neuromuscular excitability, and promote the functional recovery of nerve cells. Electric stimulation
cannot replace operation, but it can ameliorate the degree of the postoperative recovery of neuromuscular
function, it is also indicated that electric stimulation can improve the postoperative functional recovery
and prognostic efficacy. Besides, electric stimulation is indeed an active method to promote the
rehabilitation of never function postoperatively, it can exercise muscle passively, prevent muscular
atrophy, and lead to muscular contraction immediately after nerve recovery, so it is an effective
therapeutic method[7].
The nerve sensibility is weak at early period after operation for nerve injury[8]. In our previous study,
mode one or mode five with stronger stimulation was applied mainly to stimulate neural regeneration.
After early treatment, the sensitivity of the axonal regenerated nerve became stronger, so mode three or
mode four with weaker stimulative intensity was more suitable, and the stimulation to nerve should be
relieved, muscle was mainly stimulated to help to treat disuse muscular atrophy and establish the
recontrolling of nerve to muscle. The main parameters during the whole process included pulse
amplitude of 0-70 V, pulse width of 0.2-4.0 ms and frequency of 0-110 Hz. At late neural regeneration,
the sensitivity of nerve to stimulation was reduced after myelinization, and the stimulative intensity
could be properly enhanced at this moment, and the frequency could be adjusted to 20 Hz, which was
close to the physiological frequency for nerve.
The function of peripheral nerve is to transmit central information to the motor end plate and sensory
corpuscle of extremities, and then give the acquired information the extremities feel back to the central
system[9]. Therefore, the function of peripheral nerve is closely correlated with the activities of cerebral
cortex and spinal cord, and the transmission of the self physiological electroexcitative pulse is not
negligible at the same time of comprehensive therapy. The active exercise should be combined with the
active compensation of limb function, the consciousness training for the paralytic limbs should be
emphasized, and the peripheral nerve injury should be treated in the cooperation of active electric
activities of central electroexcitation of the patients. Neurotrophic drugs should be taken at the same time
to get the satisfactory effect of functional recovery.
The efficacy can be affected by the site and type of the nerve injury, beginning time and methods of
repair, and the age of the patients, etc[10]. Besides forearm flexor muscle group and leg flexor muscle
group respectively, ulnar nerve and tibial nerve also dominates the intrinsic muscles of hands or feet
respectively. Intrinsic muscles have small size and fewer muscle fiber, which is easy to become atrophy
and degeneration after long-term denervation. After elevation nerve injury repair, the intrinsic muscles
of hands or feet need longer time to recover and affect the evaluation of effect after repair[11]. Besides,
the motor and sensory nerve fibers in distal nerve tract are mixed together, and the mis-growth of motor
and sensory nerve exists, whereas the motor and sensory tracts are distinctly distinguished at distal nerve
tract, especially close to the nervous ramification, and nerve tracts of different functions have better
apposition, so has more satisfactory efficacy.
REFERENCES
1. Zanakis MF. Differential effects of various electrical parameters on peripheral and central nerve
regeneration. Acupunct Electrother Res 1990;15(3-4):185-91
2. Shen JN, Zhu JK. Electrophysiological Evaluation of peripheral nerve injury and its repair.
Zhonghua Xianwei Waike Zazhi 1993;16（3）：225-7
3. Jiang B, Yang PJ. The problem of rehabilitation after peripheral nerve injuries on extremities.
Xiandai Kangfu 2000;4(12):1763-5
4. Bai YL, Hu YS, Lin WP, et al. Quantitative evaluation of transcutaneous electric stimulation for
promoting peripheral nerve regeneration and functional recovery. Zhongguo Linchuang Kangfu
2005;9(21):49-51
5. Lankford KL, Letourneau PC. Evidence that calcium may control neurite outgrowth by regulating
the stability of actin filaments. J Cell Biol 1989;109(3):1229-43
6. Yang Q, Zhang ZY, Yu ZY. Electrical stimulation therapeutics of injury in peripheral nerve. Xiandai
Kangfu 2000;4(11):1613-5
7. Liu YH, Hou XM, Li HX. Clinical application of accelerating peripheral nerve regeneration by
pulsative electrical stimulation. Gu yu Guanjie Sunshang Zazhi 2000;15(5):342-3
8. Zhu JK, Lu CX, Wang SC, et al. Surgery of the Peripheral Nerve. Haikou: Sanhuan Publishing
House 1991:34
9. Yang PJ, Wang MF, Chen KM. Rehabilitation therapy after peripheral nerve injuries in the upper
extremities. Zhonghua Shouwaike Zazhi 1997;13(4):210-2
10. Li QF, Fan CY, Gu YD. A clinical study on percutaneous electric stimulation in the promotion of
peripheral nerve regeneration. Zhonghua Xianwei Waike Zazhi 1995;18(4):253-6
11. Liu NP, Sun HF, Zhou LM, et al. A clinical study on percutaneous nerve-muscle electric
stimulation in the promotion of peripheral neuranagenesis. Zhonghua Wuli Yixue yu Kangfu Zazhi
2003;25(11):691-3
(Edited by Ao Q/Yin YL/Wang L)