It was reported that nerve fibers were present in the inner part of lumbar intervertebral discs from patients with discogenic pain. Because there are no nerve fibers in the inner part of annulus fibrosus in normal condition, this finding suggests nerve ingrowth into the disc may be a cause of discogenic pain. Disc degeneration is often asymptomatic, thus, to understand the differences between symptomatic and asymptomatic disc, it is necessary to understand the pathogenesis of discogenic pain. We recently revealed that over 90% of the nociceptive dorsal root ganglion (DRG) neurons innervating the disc are sensitive to nerve growth factor (NGF), which is related to inflammatory pain. This indicates that discogenic pain is closely related to inflammation and NGF may play a key role. The increase of inflammatory mediators in symptomatic discs has been reported; we therefore studied the effects of disc inflammation and found that it induces sensitization of disc-innervating neurons and nerve ingrowth into the disc. More recently, it was shown that annular rupture induces nerve ingrowth, an increase of inflammatory mediators in the disc, and upregulation of calcitonin gene-related peptide, a pain-related molecule in DRGs. These findings led us to believe that annular rupture triggers inflammation and nerve ingrowth, inflammatory mediators then further promote nerve ingrowth into the disc and sensitization of disc-innervating neurons, and discogenic pain finally becomes chronic. NGF, found in symptomatic discs, may act as a key factor in generating chronic discogenic pain by sensitizing disc-innervating neurons and stimulating nerve ingrowth into the disc.
Calcitonin Gene-Related Peptide ; Diagnosis-Related Groups ; Ganglia, Spinal ; Humans ; Inflammation ; Intervertebral Disc ; Intervertebral Disc Degeneration ; Nerve Fibers ; Nerve Growth Factor ; Neurons ; Rupture ; Up-Regulation

Objective: In 2000, the Ministry of Health and Welfare issued an advisory that recommended intake of 0.4mg of folic acid in dietary supplements to reduce the risk of development of neural tube defects.  Since subsequent reports of questionnaire surveys by various investigators showed a low in the intake rate, we surveyed and evaluated the folic acid intake rate among the pregnant women consulting the Japan Drug Information Institute in Pregnancy.
Methods: We evaluated differences in folic acid intake rate according to the consulting women’s background factors. i.e., age, pregnancy planning, pregnancy history, and taking of anticonvulsant drugs in the 1053 women capable of participating in the survey among the 1061 pregnant women who requested a consultation with the Japan Drug Information Institute in Pregnancy between April 2006 and August 2008.
Results: According to the result of our survey, the intake rate of folic acid was 29% of the 1053 pregnant women.  The only 3 women of the 42 pregnant women taking anticonvulsant drugs took folic acid before they got pregnant.
Conclusion: Even now, 8 years after the Ministry of Health and Welfare advisory, the folic acid intake rate is low.  Drawing upon successful measures promoting intake in the U.S. and Canada,we play a vital role in delivering this critical health information to pregnant women.

Objective: Atopic dermatitis (AD) is one of the known risk factors for Staphylococcus aureus infection. The authors report the case of a patient with cervical spondylosis and AD who developed delayed surgical site infection after posterior cervical instrumented surgery.Patient: A 39-year-old male presented to our hospital with paralysis of the left upper extremity without any cause or prior injury. He had a history of severe AD. We performed C3–C7 posterior decompression and instrumented fusion based on the diagnosis of cervical spondylotic amyotrophy. One year after surgery, his deltoid and bicep muscle strength were fully recovered. Nevertheless, his neck pain worsened 2 years after surgery following worsening of AD. One month after that, he developed severe myelopathy and was admitted to our hospital. Radiographic findings showed that all the screws had loosened and the retropharyngeal space had expanded. Magnetic resonance imaging and computed tomography showed severe abscess formation and destruction of the C7/T1 vertebrae.Result: We diagnosed him with delayed surgical site infection. Methicillin-resistant Staphylococcus aureus was identified on abscess culture. The patient responded adequately to treatment with antibiotic therapy and two debridements and the infection subsided.Conclusion: We should consider the possibility of delayed surgical site infection when conducting instrumented spinal surgery in patients with severe AD.