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a 65-year - old woman had a 5-year history of lower back pain following posterolateral interbody fusion surgery .
she was treated with fluoroscopically guided epidural injections and medications including non - steroidal anti - inflammatory drugs and muscle relaxants for 6 months .
the patient complained of sleep disturbances and was depressed from experiencing severe pain and activity restriction .
the tms machine was set at a frequency of 1 hz and 100% of the resting motor threshold for 20 min .
a figure - of - eight - shaped coil magnetic stimulator was placed on the skull overlying the left prefrontal cortex .
we assessed treatment outcomes using the pain numerical rating scale ( nrs ) , the beck depression inventory ( bdi ) , the insomnia severity index ( isi ) and the pain disability index ( pdi ) .
2 ) . nrs ( 0 = no pain , 100 = worst pain imaginable ) decreased from 80 to 30 , and depression , assessed by the bdi self - report scale ( 0 to 63 ) , decreased from 50 ( extreme depression ) to 11 ( mild mood disturbance ) .
insomnia , assessed by isi ( 0 to 28 ) , improved from 23 ( severe insomnia ) to 10 ( sub - threshold insomnia ) .
disability was assessed by pdi ( 0 to 70 ) , and also improved from 63 to 32 .
the patient was very satisfied with the treatment results , and symptom improvement was maintained for at least 3 months following treatment .
any side effects such as headache and hearing problem were not found . a 61-year - old female patient had a 1-year history of lower back and bilateral leg pain .
she had a laminectomy 1 year previously , and the pain was aggravated following the operation .
she was treated with medications including non - steroidal anti - inflammatory drugs and muscle relaxants for 3 months .
the patient received a total of 15 sessions , five times per week for 3 weeks .
pain improved by 50% compared to baseline levels as assessed by nrs decreasing from 80 to 40 .
insomnia improved from moderate levels to sub - threshold levels as assessed by isi ( 0 to 28 ) , improving from 21 to 13 .
depression as assessed by bdi decreased from 26 ( moderate ) to 13 ( mild mood disturbance ) .
the patient was very satisfied with the results , and the effects were maintained for at least 3 months following conclusion of the treatment .
a 65-year - old woman had a 5-year history of lower back pain following posterolateral interbody fusion surgery .
she was treated with fluoroscopically guided epidural injections and medications including non - steroidal anti - inflammatory drugs and muscle relaxants for 6 months .
the patient complained of sleep disturbances and was depressed from experiencing severe pain and activity restriction .
the tms machine was set at a frequency of 1 hz and 100% of the resting motor threshold for 20 min .
a figure - of - eight - shaped coil magnetic stimulator was placed on the skull overlying the left prefrontal cortex .
we assessed treatment outcomes using the pain numerical rating scale ( nrs ) , the beck depression inventory ( bdi ) , the insomnia severity index ( isi ) and the pain disability index ( pdi ) .
2 ) . nrs ( 0 = no pain , 100 = worst pain imaginable ) decreased from 80 to 30 , and depression , assessed by the bdi self - report scale ( 0 to 63 ) , decreased from 50 ( extreme depression ) to 11 ( mild mood disturbance ) .
insomnia , assessed by isi ( 0 to 28 ) , improved from 23 ( severe insomnia ) to 10 ( sub - threshold insomnia ) .
disability was assessed by pdi ( 0 to 70 ) , and also improved from 63 to 32 .
the patient was very satisfied with the treatment results , and symptom improvement was maintained for at least 3 months following treatment .
a 61-year - old female patient had a 1-year history of lower back and bilateral leg pain .
she had a laminectomy 1 year previously , and the pain was aggravated following the operation .
she was treated with medications including non - steroidal anti - inflammatory drugs and muscle relaxants for 3 months .
the patient received a total of 15 sessions , five times per week for 3 weeks .
2 ) . pain improved by 50% compared to baseline levels as assessed by nrs decreasing from 80 to 40 .
insomnia improved from moderate levels to sub - threshold levels as assessed by isi ( 0 to 28 ) , improving from 21 to 13 .
depression as assessed by bdi decreased from 26 ( moderate ) to 13 ( mild mood disturbance ) .
the patient was very satisfied with the results , and the effects were maintained for at least 3 months following conclusion of the treatment .
various neurostimulation methods have been applied in the treatment of chronic pain including the following : peripheral nerve stimulation ( pns ) , spinal cord stimulation ( scs ) , deep brain stimulation ( dbs ) , motor cortex stimulation ( mcs ) , and repetitive transcranial magnetic stimulation ( rtms ) .
the mechanism of cortical stimulation for pain relief is based on the modification of neuronal excitability . in chronic pain states ,
several studies have reported the prevalence of major depression in chronic lower back pain over a 6-month period ( 21 - 45% ) .
depression is the result of the imbalance and dysfunction of neurotransmitters such as serotonin , norepinephrine , and dopamine .
several studies have shown that pain and depression are conducted through the same descending pathways in the central nervous system forming a biological link between these two conditions .
severe pain , restriction of daily activities , and pain refractory to treatment are related to depression .
patients with both pain and depression should be treated for these conditions simultaneously for optimal treatment outcomes .
a tms machine delivers a magnetic field to the brain using a magnetic stimulator to stimulate neurons to release neurotransmitters into the synaptic cleft .
there is a study that tms treatment of the left prefrontal cortex for at least 3 weeks has an antidepressant effect .
.   showed remission in 30 - 40% of cases which was maintained for 3 months following treatment in 58% of the patients .
the bdi is a useful questionnaire utilizing a self - rated scale for observing the level of depression .
a reduction in bdi scores was achieved in both patients following the conclusion of the treatment .
sleep impairment occurred in 55% of chronic lower back pain patients , and over 50% of insomniacs had moderate to severe levels of insomnia .
this questionnaire is a valid and reliable tool that contains seven statements relating to insomnia severity , producing a range from 0 to 28 .
a tms study evaluating insomnia showed a significant improvement in sleep problems , with a lower recurrence rate compared to treatment with medication and psychotherapy .
tms has been used for the treatment of various chronic neuropathic pain disorders , including phantom limb pain , fibromyalgia , complex regional pain syndrome , and central pain following stroke or spinal cord injury .
tms acts on pain - modulating systems in the diencephalon and descending pain pathways from the brainstem to the spinal cord .
endogenous opioid systems may also be affected by tms - induced analgesia depending on the stimulation site .
tms has produced analgesia with chronic pain , but the improvement depends on various factors , including the stimulation frequency , stimulation site , and treatment duration .
current published clinical trials on the efficacy of rtms in treating depression are almost certainly suboptimal ( e.g. duration of two weeks ) .
the data support positive outcomes for rtms , but not large clinical effects . however , a few studies suggest that a longer course of rtms is necessary for optimal therapeutic outcomes .
found that over 3 weeks , the active rtms treatment was superior to the sham tms . in our study
, subjects with depression , insomnia and chronic back pain were treated each weekday for 3 to 4 weeks .
generally higher frequencies ( > 5 hz ) are excitatory , and lower frequencies ( < 1 hz ) are inhibitory .
some studies suggest tms at 10 hz had better results than 5 hz , and 1 hz did not produce a significant effect .
however , our patients received tms at a 1-hz frequency , and experienced significant pain relief .
tms effects vary amongst individuals , and further study is required to determine the optimal treatment protocols .
we used the pain disability index ( pdi ) because it provides a simple questionnaire to assess the impact of pain in terms of activity restriction .
the questionnaire addresses seven items on a scale of 0 - 70 : family and home responsibilities , recreation , social activity , occupation , sexual behavior , self - care , and life - support activity .
the most common adverse effect was a mild and instant headache , which occurred in 23% of patients .
tms is a safe treatment modality when manufacturer guidelines are followed , and patients are monitored during the treatment .
prospective randomized controlled studies are needed to confirm the efficacy of tms treatment of insomnia , depression , and pain from chronic low back pain syndrome .
future studies should focus on tms instrument settings , including the stimulation site , frequency , and duration .
in conclusion , these cases show the successful results from tms therapy for the treatment of depression , sleep disorders , and pain .
we suggest that rtms could be a safe and effective treatment option for patients with chronic low back pain resulting in depression and insomnia .
further studies are required to verify the positive outcomes of tms treatment for chronic low back pain .
transcranial magnetic stimulation ( tms ) is a noninvasive and safe technique for motor cortex stimulation . 
 tms is used to treat neurological and psychiatric disorders , including mood and movement disorders . 
 tms can also treat several types of chronic neuropathic pain . 
 the pain relief mechanism of cortical stimulation is caused by modifications in neuronal excitability . 
 depression is a common co - morbidity with chronic pain . 
 pain and depression should be treated concurrently to achieve a positive outcome . 
 insomnia also frequently occurs with chronic lower back pain . 
 several studies have proposed hypotheses for tms pain management . 
 herein , we report two cases with positive results for the treatment of depression and insomnia with chronic low back pain by tms .