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Takahiro Shimazaki, Kei Yamada, Kimiaki Sato, Kotaro Jimbo, Hidetomo Nakamura, Masafumi Goto, Tsunemasa Matsubara, Kenji Mizokami, Shoji Iwahashi, Takeharu Sasaki, and Naoto Shiba

OBJECTIVE

The primary treatment for atlantoaxial rotatory fixation (AARF) remains controversial. The aim of this study was to investigate the primary treatment for AARF and create an algorithm for primary treatment.

METHODS

The authors analyzed the data of 125 pediatric patients at four medical institutions from April 1989 to December 2018. The patients were reported to have neck pain, torticollis, and restricted neck range of motion and were diagnosed according to the Fielding classification as type I or II. As a primary treatment, 88 patients received neck collar fixation, and 28 of these patients did not show symptom relief and required Glisson traction. Thirty-seven patients were primarily treated with Glisson traction. In total, 65 patients, including neck collar treatment failure patients, underwent Glisson traction in hospitals.

RESULTS

The success rate of treatment was significantly higher in the Glisson traction group (97.3%) than in the neck collar fixation group (68.2%) (p = 0.0001, Wilcoxon test). In the neck collar effective group, Fielding type I was more predominant (p = 0.0002, Wilcoxon test) and the duration from onset to the first visit was shorter (p = 0.02, Wilcoxon test) than that in the neck collar ineffective group. Using multivariate logistic regression analysis with the above items, the authors generalized from the estimated formula: logit [p(success group by neck collar fixation group)|duration from onset to the first visit (x1), Fielding type (x2)] = 0.4(intercept) − 0.15x1 + 1.06x2, where x1 is the number of days and x2 = 1 (for Fielding type I) or −1 (for Fielding type II). In cases for which the score is a positive value, the neck collar should be chosen. Conversely, in cases for which the score is a negative value, Glisson traction should be the first choice.

CONCLUSIONS

According to this formula, in patients with Fielding type I AARF, neck collar fixation should be allowed only if the duration from onset is ≤ 10 days. In patients with Fielding type II, because the score would be a negative value, Glisson traction should be performed as the primary treatment.

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Takuma Ohmichi, Masaki Kondo, Masahiro Itsukage, Hidetaka Koizumi, Shigenori Matsushima, Nagato Kuriyama, Kazunari Ishii, Etsuro Mori, Kei Yamada, Toshiki Mizuno, and Takahiko Tokuda

OBJECTIVE

The gold standard for the diagnosis of idiopathic normal pressure hydrocephalus (iNPH) is the CSF removal test. For elderly patients, however, a less invasive diagnostic method is required. On MRI, high-convexity tightness was reported to be an important finding for the diagnosis of iNPH. On SPECT, patients with iNPH often show hyperperfusion of the high-convexity area. The authors tested 2 hypotheses regarding the SPECT finding: 1) it is relative hyperperfusion reflecting the increased gray matter density of the convexity, and 2) it is useful for the diagnosis of iNPH. The authors termed the SPECT finding the convexity apparent hyperperfusion (CAPPAH) sign.

METHODS

Two clinical studies were conducted. In study 1, SPECT was performed for 20 patients suspected of having iNPH, and regional cerebral blood flow (rCBF) of the high-convexity area was examined using quantitative analysis. Clinical differences between patients with the CAPPAH sign (CAP) and those without it (NCAP) were also compared. In study 2, the CAPPAH sign was retrospectively assessed in 30 patients with iNPH and 19 healthy controls using SPECT images and 3D stereotactic surface projection.

RESULTS

In study 1, rCBF of the high-convexity area of the CAP group was calculated as 35.2–43.7 ml/min/100 g, which is not higher than normal values of rCBF determined by SPECT. The NCAP group showed lower cognitive function and weaker responses to the removal of CSF than the CAP group. In study 2, the CAPPAH sign was positive only in patients with iNPH (24/30) and not in controls (sensitivity 80%, specificity 100%). The coincidence rate between tight high convexity on MRI and the CAPPAH sign was very high (28/30).

CONCLUSIONS

Patients with iNPH showed hyperperfusion of the high-convexity area on SPECT; however, the presence of the CAPPAH sign did not indicate real hyperperfusion of rCBF in the high-convexity area. The authors speculated that patients with iNPH without the CAPPAH sign, despite showing tight high convexity on MRI, might have comorbidities such as Alzheimer’s disease.

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Kimiaki Yokosuka, Jin Soo Park, Kotaro Jimbo, Kei Yamada, Kimiaki Sato, Michiyo Tsuru, Masayoshi Takeuchi, Sho-Ichi Yamagishi, and Kensei Nagata

Object

The authors sought to clarify the role, if any, of advanced glycation end-products (AGEs) in disc degeneration.

Methods

Intervertebral discs were analyzed for the presence of AGEs and of their receptor (RAGE) by immunohistochemical analysis. Reverse transcriptase polymerase chain reaction (RT-PCR) was performed to detect any RAGE gene expression, and real-time PCR was used to quantify messenger RNA (mRNA) levels of aggrecan and collagen types I and II in nucleus pulposus cells treated with AGEs. Aggrecan protein concentration was determined by enzyme-linked immunosorbent assay.

Immunohistochemical analysis revealed that AGEs and RAGE were localized in the nucleus pulposus of the intervertebral disc. Advanced glycation end-products were found to significantly suppress the expression of aggrecan at both mRNA and protein levels in a dose- and time-dependent manner. The levels of collagen types I and II remained unchanged after treatments with AGEs.

Conclusions

These results suggest that the accumulation of AGEs and their interaction with their receptor in the nucleus pulposus might result in the downregulation of aggrecan production responsible for disc degeneration.

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Tatsuhiro Yoshida, Jin Soo Park, Kimiaki Yokosuka, Kotaro Jimbo, Kei Yamada, Kimiaki Sato, and Kensei Nagata

Object

Neurotropin is a nonprotein extract from the inflamed skin of rabbits inoculated with vaccinia virus. In the present study the authors sought to clarify the focal antiinflammatory effects of Neurotropin in intervertebral disc cells, and these effects were compared with those induced by the selective cyclooxygenase (COX)–2 inhibitor 6-methoxy-2-naphthylacetic acid (nabumetone).

Methods

Six human intervertebral disc specimens were harvested during spinal surgery for lumbar disc herniation. Cells were stimulated with 500 pg/ml of interleukin (IL)–1β in the presence of various concentrations of Neurotropin (0, 10−5, 10−4, and 10−3 Neurotropin Units/ml) or 50 μg/ml of nabumetone for 3 hours. The mRNA was extracted for polymerase chain reaction (PCR), and real-time PCR was used to quantify the mRNA levels of COX- 2, tumor necrosis factor (TNF)–α, and phospholipase A2. Cyclooxygenase-2, TNFα, and prostaglandin E2 (PGE2) protein concentrations were each determined by enzyme-linked immunosorbent assay.

Results

Neurotropin was found to significantly suppress the expression of COX-2 and TNFα at mRNA levels as well as the concentration of COX-2 at protein levels in a dose-dependent manner. Nabumetone was found to significantly increase COX-2 at mRNA levels but directly suppress the concentration of PGE2 in culture medium.

Conclusions

Results in this study suggest that Neurotropin has an analgesic effect through the suppression of COX-2 and TNFα in a focal area, and nabumetone shows this same effect through the suppression of PGE2 production. Thus, Neurotropin could decrease pain by blocking the central pain pathway or increasing focal antiinflammatory effects.

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Sho Kobayashi, Yukihiro Matsuyama, Kenichi Shinomiya, Shigenori Kawabata, Muneharu Ando, Tsukasa Kanchiku, Takanori Saito, Masahito Takahashi, Zenya Ito, Akio Muramoto, Yasushi Fujiwara, Kazunobu Kida, Kei Yamada, Kanichiro Wada, Naoya Yamamoto, Kazuhiko Satomi, and Toshikazu Tani

Object

Although multimodal intraoperative spinal cord monitoring provides greater accuracy, transcranial electrical stimulation motor evoked potential (TcMEP) monitoring became the gold standard for intraoperative spinal cord monitoring. However, there is no definite alarm point for TcMEPs because a multicenter study is lacking. Thus, based on their experience with 48 true-positive cases (that is, a decrease in potentials followed by a new neurological motor deficit postoperatively) encountered between 2007 and 2009, the authors set a 70% decrease in amplitude as the alarm point for TcMEPs.

Methods

A total of 959 cases of spinal deformity, spinal cord tumor, and ossification of the posterior longitudinal ligament (OPLL) treated between 2010 and 2012 are included in this prospective multicenter study (18 institutions). These institutions are part of the Japanese Society for Spine Surgery and Related Research monitoring working group and the study group on spinal ligament ossification. The authors prospectively analyzed TcMEP variability and pre- and postoperative motor deficits. A 70% decrease in amplitude was designated as the alarm point.

Results

There were only 2 false-negative cases, which occurred during surgery for intramedullary spinal cord tumors. This new alarm criterion provided high sensitivity (95%) and specificity (91%) for intraoperative spinal cord monitoring and favorable accuracy, except in cases of intramedullary spinal cord tumor.

Conclusions

This study is the first prospective multicenter study to investigate the alarm point of TcMEPs. The authors recommend the designation of an alarm point of a 70% decrease in amplitude for routine spinal cord monitoring, particularly during surgery for spinal deformity, OPLL, and extramedullary spinal cord tumor.