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

Triplet surveys were conducted in the city of Xi' an and two villages (one in the vicinity and the other at a distance) in Shaanxi Province in China in October-November (when agricultural activitis were low), 1997, to elucidate nutrient intakes with a focus on possible urban-rural differences. Total food duplicate samples were collected from non-smoking and non-habitually drinking adult healthy women (about 50 subjects per site and 149 in total). The nutrient intakes were estimated from the weight of food items in reference to national food composition tables. On average, the women took 1873 kcal energy, 54 g protein and 37 g lipid per day, with a lipid energy ratio of18.4%. Both excess and insufficient energy intake was observed as a result of food intake analysis and body mass index determination. With regard to minor nutrient intakes, insufficiency was serious in the case of calcium, vitamin A and vitamin B2, but not with iron. Whereas dependency on plant foods for sources of energy and protein was common to the three regions, Xi' an people consumed more animal foods than those in the villages. Intake of fish and shellfish was quite low throughout the three regions. Among the four types of cereals, wheat was consumed most substantially in the three regions and in three meals (except for the village where people essentially did not take lunch in reflection of low agricultural activities), whereas rice was consumed more in Xi' an than in the two villages. Maize consumption was higher in the two villages (especially for breakfast) than in the city.In contrast, foxtail millet (although in small amounts) was taken primarily in Xi'an and only at the time of breakfast.

STUDY DESIGN: Retrospective cohort study. PURPOSE: To investigate the effect of spinal correction on respiratory muscle strength in patients with Duchenne muscular dystrophy (DMD). OVERVIEW OF LITERATURE: Several studies have reported that scoliosis correction in patients with DMD does not improve pulmonary function. In these studies, pulmonary function was evaluated using the traditional spirometric values of percent vital capacity (%VC) and percent forced vital capacity (%FVC). However, traditional spirometry may not be suitable for patients with DMD because the results can be influenced by patient fatigue or level of understanding. Therefore, we evaluated respiratory function focusing on respiratory muscle strength using maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and sniff nasal inspiratory pressure (SNIP), in addition to %VC and %FVC. METHODS: We retrospectively reviewed 16 patients with DMD who underwent spinal correction surgery between 2006 and 2011 at Kitasato University Hospital. All patients were males, and the mean age was 13.5 years. Respiratory muscle strength was evaluated using MIP, MEP, and SNIP. Measurements were obtained preoperatively and at 1 and 6 months postoperatively, and %VC and %FVC were obtained preoperatively and within 6 months postoperatively. RESULTS: The mean preoperative and postoperative %VC values were 54.0% and 51.7%, whereas the mean %FVC values were 53.9% and 53.2%, respectively. The mean MIP, MEP, and SNIP values obtained preoperatively and at 1 and 6 months postoperatively were as follows: MIP, 40.5, 42.7 and 47.2 cm H₂O; MEP, 26.0, 28.0, and 29.0 cm H₂O; and SNIP, 33.4, 33.0, and 33.0 cm H₂O; respectively. The mean MIP and MEP values significantly improved postoperatively. There were no significant differences in SNIP, %VC, or %FVC preand postoperatively. CONCLUSIONS: By focusing on respiratory muscle strength, our results suggest that scoliosis correction in patients with DMD might have a favorable effect on respiratory function.
Cohort Studies ; Fatigue ; Humans ; Male ; Muscular Dystrophy, Duchenne* ; Respiratory Muscles* ; Retrospective Studies ; Scoliosis* ; Spirometry ; Vital Capacity

STUDY DESIGN: Retrospective case series. PURPOSE: To examine the most effective duration of teriparatide use for spinal fusion in women with postmenopausal osteoporosis. OVERVIEW OF LITERATURE: We reported that daily subcutaneous injection of teriparatide (parathyroid hormone) significantly improved bone union after instrumented lumbar posterolateral fusion (PLF) in women with postmenopausal osteoporosis when compared with oral administration of bisphosphonate. However, the most effective duration of teriparatide use for spinal fusion has not been explored. METHODS: Forty-five women with osteoporosis diagnosed with degenerative spondylolisthesis from one of the three treatment groups were evaluated based on: short-duration treatment (average, 5.5 months; n=15; daily subcutaneous injection of 20 microg teriparatide), long-duration treatment (average, 13.0 months; n=15; daily subcutaneous injection of 20 microg teriparatide), and bisphosphonate treatment (average, 13.0 months; n=15; weekly oral administration of 17.5 mg risedronate). All patients underwent PLF with a local bone graft. Fusion rate and duration of bone union were evaluated 1.5 years after surgery. RESULTS: Bone union rate and average duration for bone union were 92% and 7.5 months in the long-duration treatment group, 80% and 8.5 months in the short-duration treatment group, and 70% and 10.0 months in the bisphosphonate treatment group, respectively. Results of bone union rate and average duration for bone union in the teriparatide treatment groups were significantly superior to those in the bisphosphonate treatment group (p<0.05); whereas, significantly superior results were observed in long-duration treatment group when compared with short-duration treatment group (p<0.05). CONCLUSIONS: Daily injection of teriparatide for bone union was more effective than oral administration of bisphosphonate. Furthermore, a longer period of teriparatide treatment for bone union was more effective than a shorter period of same treatment.
Administration, Oral ; Female ; Humans ; Injections, Subcutaneous ; Osteoporosis ; Osteoporosis, Postmenopausal ; Retrospective Studies ; Spinal Fusion ; Spondylolisthesis ; Teriparatide* ; Transplants

PURPOSE: Bupivacaine is commonly used for the treatment of back pain and the diagnosis of its origin. Nonunion is sometimes observed after spinal fusion surgery; however, whether the nonunion causes pain is controversial. In the current study, we aimed to detect painful nonunion by injecting bupivacaine into the disc space of patients with nonunion after anterior lumbar interbody fusion (ALIF) surgery for discogenic low back pain. MATERIALS AND METHODS: From 52 patients with low back pain, we selected 42 who showed disc degeneration at only one level (L4-L5 or L5-S1) on magnetic resonance imaging and were diagnosed by pain provocation on discography and pain relief by discoblock (the injection of bupivacaine). They underwent ALIF surgery. If the patients showed low back pain and nonunion 2 years after surgery, we injected bupivacaine into the nonunion disc space. Patients showing pain relief after injection of bupivacaine underwent additional posterior fixation using pedicle screws. These patients were followed up 2 years after the revision surgery. RESULTS: Of the 42 patient subjects, 7 showed nonunion. Four of them did not show low back pain; whereas 3 showed moderate or severe low back pain. These 3 patients showed pain reduction after injection of bupivacaine into their nonunion disc space and underwent additional posterior fixation. They showed bony union and pain relief 2 years after the revision surgery. CONCLUSION: Injection of bupivacaine into the nonunion disc space after ALIF surgery for discogenic low back pain is useful for diagnosis of the origin of pain.
Back Pain ; Bupivacaine* ; Diagnosis ; Humans ; Intervertebral Disc ; Intervertebral Disc Degeneration ; Low Back Pain* ; Magnetic Resonance Imaging ; Methods ; Spinal Fusion ; Spine