Posterior cruciate ligament resection under minimum medial collateral ligament release changes tibial internal rotation, joint center gap, and varus ligament balance on joint distraction force at flexion in total knee arthroplasty.

BACKGROUND: The purpose of this study was to assess the effect of posterior cruciate ligament resection under minimum medial collateral ligament release on the joint center gap, varus ligament balance, and the rotational change of the femur and tibia. METHODS: This study included 75 knees with varus osteoarthritis that underwent total knee arthroplasty. After minimum medial collateral ligament releases and bone resection of the distal femur and proximal tibia, the joint center gap and varus ligament balance were measured before and after posterior cruciate ligament resection using a digital tensor with a joint distraction force of 89, 133, 178 N. The rotational changes under a distraction force of 200 N were captured using a navigation system. FINDINGS: The joint center gap and varus ligament balance at 90° and 120° of flexion significantly increased after posterior cruciate ligament resection with distraction forces of 89 N (90°: 0.4 mm / 0.9° and 120°: 0.5 mm / 0.8°), 133 N (90°: 0.9 mm / 1.3° and 120°: 0.9 mm / 1.1°), 178 N (90°: 1.5 mm / 1.9° and 120°: 1.5 mm / 1.5°). Tibial internal rotation significantly increased after posterior cruciate ligament resection at 90° (1.9°) and 120° (2.2°). INTERPRETATION: Joint distraction forces after posterior cruciate ligament resection increased the tibial internal rotation, joint center gap, and varus ligament balance at flexion. These findings indicate that posterior cruciate ligament resection should increase the lateral gap more than the medial gap due to tibial internal rotation at flexion. (245 words).

Prognostic factors for spontaneous spinal epidural hematoma: a multicenter case-control study.

BACKGROUND: To determine the optimal treatment for spontaneous spinal epidural hematoma (SSEH). The aim of this study was to identify factors associated with SSEH. METHODS: In 62 patients with SSEH, several patient-related parameters were analyzed as candidate factors associated with Frankel grade before treatment or at the last follow-up. These parameters were compared between patients with and without surgery. In addition, multivariate ordinal logistic regression analysis was used to identify factors significantly associated with Frankel's grade before treatment or at the last follow-up. RESULTS: There were significant differences in age, location of the hematoma, and Frankel grade before treatment and at the last follow-up between surgical and nonsurgical cases in all patients, but there were no significant differences in any of these parameters when comparing patients with pre-treatment Frankel grade C. The location of the hematoma was significantly associated with the severity of paralysis before treatment. In surgical cases, the time from onset to surgery and the location of the hematoma was significantly associated with the prognosis. When the time from onset to surgery was evaluated using the criteria of 12, 24, and 48 h, 24 and 48 h had a significant impact on the prognosis. In the analysis of nonsurgical cases, only the vertical size of the hematoma was significantly associated with prognosis. CONCLUSION: The time from onset to surgery and the location of the hematoma were prognostic factors in surgical cases, while the vertical size of the hematoma was a prognostic factor in nonsurgical cases.

Population Pharmacokinetic Analysis and Dosing Optimization Based on Unbound Daptomycin Concentration and Cystatin C in Nonobese Elderly Patients with Hypoalbuminemia and Chronic Kidney Disease.

PURPOSE: This study evaluated the population pharmacokinetics of daptomycin in nonobese elderly patients with hypoalbuminemia and chronic kidney disease (CKD) using the glomerular filtration rate estimated from cystatin C (eGFRcys) and estimated its optimal dose. METHODS: We performed population pharmacokinetic analysis of the unbound concentrations of daptomycin. The probability of target attainment of 90% for achieving an area under the concentration-time curve of unbound daptomycin at steady state/ minimum inhibitory concentration ratio of ≥66.6 was stochastically simulated. RESULTS: In the population pharmacokinetic analysis of 25 patients aged ≥65 years, the two-compartment model using eGFRcys and age as covariates of clearance in central compartment of unbound daptomycin were optimal. The unbound fraction rate (fu) was 0.05-0.14. According to the Monte Carlo simulation, the optimal doses for patients with eGFRcys of 20-60 mL/min and aged 65-95 years were calculated as 200-500 mg q24h. CONCLUSION: These results suggest that establishing the dose using total concentrations may result in under- or overestimation caused by alterations in fu. The optimal dose for nonobese elderly patients with hypoalbuminemia and CKD depends on eGFRcys and age, and a standard dose may be insufficient for some patients.

Assessment of Long-Term Anterior and Posterior Topographic Changes in the Cornea After Ptosis Surgery Using Fourier Harmonic Analysis.

PURPOSE: We aimed to assess the corneal refractive changes induced by ptosis surgery in patients with acquired ptosis using Fourier harmonic analysis. METHODS: This retrospective observational study enrolled consecutive patients who underwent levator aponeurotic surgery for acquired ptosis at the Department of Ophthalmology in the University of Tokyo Hospital from May 2016 to January 2018. Best corrected visual acuity, central corneal thickness, average keratometric corneal power (AvgK), corneal astigmatism, and topographic data using Fourier analysis were analyzed preoperatively and 6 months postoperatively. RESULTS: Thirty-two eyes of 32 patients (age, 72.6 ± 8.5 years) were included in this study. There were no significant differences in best corrected visual acuity and central corneal thickness. However, there were significant decreases in anterior AvgK, anterior corneal astigmatism, and posterior corneal astigmatism 6 months postoperatively (all, P < 0.001). Fourier harmonic analysis showed that the anterior spherical component significantly decreased 6 months postoperatively (P < 0.001). There were no significant differences in other components of the anterior and posterior cornea. There was a significant negative correlation between preoperative posterior AvgK and changes in posterior AvgK (r = -0.891, P < 0.001) and between preoperative posterior corneal astigmatism and changes in posterior corneal astigmatism at 6 months (r = -0.858, P < 0.001). CONCLUSIONS: Anterior and posterior corneal keratometry and posterior corneal astigmatism significantly changed 6 months after ptosis surgery for acquired ptosis.

Choroidal structure as a biomarker for visual acuity in intravitreal aflibercept therapy for polypoidal choroidal vasculopathy.

PURPOSE: To investigate the relationship between choroidal structure and visual acuity after intravitreal aflibercept therapy for polypoidal choroidal vasculopathy (PCV). METHODS: We conducted a retrospective, single-centre and observational study including 18 eyes of 18 patients with PCV (73.8 ± 10.2 years of age) who were treated with three monthly intravitreal aflibercept injections followed by additional treatments in a treat-and-extend protocol. The cross-sectional images of the macula were obtained with enhanced depth imaging optical coherence tomography at baseline, at 3 months, and at 12 months. The choroidal layer was divided into luminal or stromal segments by applying binarization processing to calculate these areas. The relationships between age, spherical equivalent, best-corrected visual acuity (BCVA), baseline value, or changes in the luminal or the stromal areas, and the BCVA change at 12 months were analysed using multiple regression analyses and model selection procedures. RESULTS: Both stromal and luminal areas were decreased at 3 and 12 months compared to baseline areas (5% and 9% at 3 months, 6% and 12% at 12 months, p < 0.0001, p < 0.0001, p < 0.0001 and p < 0.0001, respectively). Greater improvement of visual acuity (VA) at 12 months was significantly associated with younger age, greater spherical equivalent, worse baseline BCVA, greater baseline luminal area, and smaller baseline stromal area. CONCLUSIONS: Choroidal structure might be useful as a new biomarker for potential Visual outcomes after intravitreal aflibercept therapy for PCV.

Effects of alcohol abstinence on glucose metabolism in Japanese men with elevated fasting glucose: A pilot study.

It has been demonstrated that moderate alcohol consumption provides protection against the development of type 2 diabetes. However, several other reports suggested that moderate alcohol intake may increase the risk of type 2 diabetes in non-obese Japanese. The aim of present study was to investigate the effect of 1-week alcohol abstinence on hepatic insulin sensitivity and fasting plasma glucose (FPG) in non-obese Japanese men. We recruited 8 non-obese Japanese men with mildly elevated FPG and drinking habits alcohol (mean frequency; 5.6 ± 2.5 times/week, mean alcohol consumption; 32.1 ± 20.0 g/day). Before and after the 1-week alcohol abstinence, we used the 2-step hyperinsulinemic-euglycemic clamp to measure endogenous glucose production (EGP) and insulin sensitivity (IS) in muscle and liver. One-week alcohol abstinence significantly reduced both FPG by 7% (from 105.5 ± 11.7 to 98.2 ± 7.8 mg/dl, P < 0.01) and fasting EGP by 6% (from 84.1 ± 4.2 to 77.6 ± 1.6 mg/m2 per min, P < 0.01), respectively. Two-step clamp study showed that alcohol abstinence significantly improved hepatic-IS, but not muscle-IS. In conclusion, one week alcohol abstinence improved hepatic IS and FPG in non-obese Japanese men with mildly elevated FPG and drinking habits alcohol.

Relation Between Insulin Sensitivity and Metabolic Abnormalities in Japanese Men With BMI of 23-25 kg/m2.

CONTEXT: Although metabolic abnormalities are often developed in Asians with body mass index (BMI) of 23-25 kg/m2, the characteristics of the nonobese Asians with metabolic abnormality have not been fully understood. OBJECTIVE: The aim of this study was to investigate the clinical significance of insulin sensitivity in Japanese men with BMI of 23-25 kg/m2. DESIGN AND PARTICIPANTS: In this study, we defined hypertension, hyperglycemia, and dyslipidemia as cardiometabolic risk factors (CMRFs). We recruited subjects who met the following selection criteria: men with BMI of 21-23 kg/m2 and no CMRF (n = 24); men with BMI of 23-25 kg/m2 and no CMRF (n = 28), or one CMRF (n = 28), or at least two CMRFs (n = 14); and overweight men with metabolic syndrome (n = 20). Insulin sensitivity (IS) and ectopic fat content in muscle and liver were measured by two-step hyperinsulinemic-euglycemic clamp and 1H-magnetic resonance spectroscopy, respectively. RESULTS: Among subjects with BMI of 23-25 kg/m2, impaired IS in muscle, but not in liver, was found in those with even one CMRF, whereas impaired IS in both muscle and liver was observed in overweight men with metabolic syndrome. Liver fat accumulation and elevated liver enzymes were associated with impaired IS in both muscle and liver in those subjects. CONCLUSIONS: Among Japanese men with BMI of 23-25 kg/m2, muscle insulin resistance was present in those with even one CMRF. In this population, liver fat accumulation and/or elevated liver enzymes could be a good marker for impaired IS in both muscle and liver.

Effects of sitagliptin on ectopic fat contents and glucose metabolism in type 2 diabetic patients with fatty liver: A pilot study.

AIMS/INTRODUCTION: Recent data have shown that ectopic fat accumulation in the liver worsens hepatic glucose metabolism, suggesting that fatty liver in patients with type 2 diabetes is a therapeutic target. Glucagon-like peptide (GLP)-1 improves fatty liver, but the effect of dipeptidyl peptidase-4 inhibitor on fatty liver is still unclear. The present pilot study determined the effects of 12-week treatment with sitagliptin, a dipeptidyl peptidase-4 inhibitor, on liver fat content in type 2 diabetes with fatty liver. We also evaluated intramyocellular lipid (IMCL) and glucose kinetics during oral glucose tolerance test (OGTT) before and after the treatment. MATERIALS AND METHODS: The study participants were seven type 2 diabetes patients with fatty liver who were studied at baseline and 12 weeks after sitagliptin treatment. Intrahepatic lipid (IHL) and IMCL were assessed by (1)H magnetic resonance spectroscopy. Glucose kinetics was assessed during double-tracer OGTT (U-[(13)C]-glucose orally and 6,6-[(2)H2]-glucose intravenously). RESULTS: Sitagliptin significantly reduced glycated hemoglobin (from 7.1 ± 0.2 to 6.5 ± 0.3%, P < 0.005), but had no effects on IHL and IMCL. The glucose level diminished, whereas GLP-1 concentration increased during OGTT at the end of treatment. These changes were not accompanied by significant changes in insulin or glucagon levels. However, long-term sitagliptin treatment partially decreased the rate of appearance of oral glucose during OGTT, but did not affect endogenous glucose production or the rate of disappearance. CONCLUSIONS: It was found that 12-week sitagliptin treatment improved glycated hemoglobin and glucose excursion during OGTT in type 2 diabetes with fatty liver, independent of changes in lipid accumulation in the liver. This trial was registered with the Japan Clinical Trials Registry (UMIN-CTR000005666).

Clinical results of microsurgical bilateral decompression via unilateral approach for lumbar canal stenosis with multiple-level involvement.

OBJECT: Microsurgical decompression of the lumbar spine is a beneficial approach for selected patients of lumbar spinal stenosis (LSS). The purpose of this prospective study was to describe the clinical results of surgical treatment for microsurgical bilateral decompression via unilateral approach on patients with LSS with multiple-level involvement. MATERIALS AND METHODS: Seventy-three consecutive patients who had microsurgical bilateral decompression via unilateral approach of more than two spinal levels were included in this study. Seventy-seven patients who had surgery at a single level over the same time periods were compared as a single-level LSS group. RESULTS: The preoperative Japanese Orthopaedic Association scores averaged 11.7 points, and the postoperative scores averaged 21.2 points with an average recovery rate (RR) of 56% in the multiple-level LSS group. There was no significant difference in the RR between the groups. There were no major complications related to the surgery in the both groups. CONCLUSION: Microsurgical bilateral decompression via unilateral approach was a useful and safe operative procedure for LSS patients. Sufficient clinical results that were comparable to single-level LSS patients were obtained even in the patients with multiple-level LSS, if the patient were correctly selected and the microsurgical decompression surgery were carefully performed.

Gut dysbiosis and detection of "live gut bacteria" in blood of Japanese patients with type 2 diabetes.

OBJECTIVE: Mounting evidence indicates that the gut microbiota are an important modifier of obesity and diabetes. However, so far there is no information on gut microbiota and "live gut bacteria" in the systemic circulation of Japanese patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: Using a sensitive reverse transcription-quantitative PCR (RT-qPCR) method, we determined the composition of fecal gut microbiota in 50 Japanese patients with type 2 diabetes and 50 control subjects, and its association with various clinical parameters, including inflammatory markers. We also analyzed the presence of gut bacteria in blood samples. RESULTS: The counts of the Clostridium coccoides group, Atopobium cluster, and Prevotella (obligate anaerobes) were significantly lower (P < 0.05), while the counts of total Lactobacillus (facultative anaerobes) were significantly higher (P < 0.05) in fecal samples of diabetic patients than in those of control subjects. Especially, the counts of Lactobacillus reuteri and Lactobacillus plantarum subgroups were significantly higher (P < 0.05). Gut bacteria were detected in blood at a significantly higher rate in diabetic patients than in control subjects (28% vs. 4%, P < 0.01), and most of these bacteria were Gram-positive. CONCLUSIONS: This is the first report of gut dysbiosis in Japanese patients with type 2 diabetes as assessed by RT-qPCR. The high rate of gut bacteria in the circulation suggests translocation of bacteria from the gut to the bloodstream.

Carotid intima-media thickness progression predicts cardiovascular events in Japanese patients with type 2 diabetes.

AIMS: The aim of this retrospective study was to investigate the relationship between progression of carotid intima-media thickness (cIMT) and cardiovascular events in Japanese patients with type 2 diabetes mellitus (T2DM) and free of history of cardiovascular events. METHODS: Patients with T2DM (n=342) without history of cardiovascular events whose cIMT was assessed more than twice by ultrasonography were recruited and followed up for cardiovascular events. RESULTS: During a mean follow-up of 7.6 years, 56 (16.4%) cardiovascular events (27 coronary events and 29 cerebrovascular events) were recorded. Multivariate analysis with the Cox proportional hazard model identified cIMT progression as a significant determinant of cardiovascular events, with a hazard ratio (HR) of 2.24 (95% confidence interval; CI, 1.25-4.03, P<0.01), in addition to baseline cIMT. The Kaplan-Meier curves also showed significantly higher event rate in patients with high cIMT progression compared with those with low cIMT progression (log-rank χ(2)=6.65; P<0.01). Furthermore, the combination of high baseline cIMT and high cIMT progression was a significant predictor of cardiovascular events. CONCLUSION: Our findings suggest that cIMT progression, in addition to baseline cIMT, is a predictor of cardiovascular events in patients with T2DM without history of cardiovascular events, and that the combination of cIMT progression and baseline cIMT has a strong predictive power for such events.

Comparison of effects of cilnidipine and azelnidipine on blood pressure, heart rate and albuminuria in type 2 diabetics with hypertension: A pilot study.

Previous studies reported that both cilnidipine and azelnidipine have a renoprotective effect compared with amlodipine. The aim of this study was to compare the effects of cilnidipine and azelnidipine on blood pressure, heart rate and albuminuria. An open-label prospective crossover trial was carried out. We recruited 19 type 2 diabetics treated with amlodipine (5 mg/day) at least for 12 weeks. At study entry, amlodipine was changed to cilnidipine (10 mg/day) or azelnidipine (16 mg/day) and each administered for 16 weeks. Then, the drugs were switched and the treatment was continued for another 16 weeks. Despite no differences in 24-h blood pressure and heart rate between cilnidipine and azelnidipine, treatment with cilnidipine resulted in a greater reduction in urinary albumin:creatinine ratio than azelnidipine. Our results suggested that cilnidipine is more efficient in reducing albuminuria than azelnidipine independent of its blood pressure lowering effect in type 2 diabetic patients with hypertension. This trial was registered with UMIN (no. 000007201).

Morningness-eveningness questionnaire score correlates with glycated hemoglobin in middle-aged male workers with type 2 diabetes mellitus.

AIMS/INTRODUCTION: 'Morningness' and 'eveningness' represent the sleep-wake patterns of the circadian rhythm might also affect glycemic control in patients with type 2 diabetes. The aim of this study was to examine the relationship between the morningness-eveningness trait and metabolic parameters. MATERIALS AND METHODS: The study participants comprised 101 Japanese male workers with type 2 diabetes treated in an outpatient clinic. Blood samples were obtained, and a morningness-eveningness questionnaire (MEQ), where a high score represents morningness; and the Pittsburg Sleep Quality Index (PSQI), where the higher the score the worse the sleep quality, were carried out. RESULTS: MEQ correlated positively with age, and high-density lipoprotein cholesterol (HDL-C), and negatively with glycated hemoglobin (HbA1c) and PSQI. Multivariate regression analysis showed that MEQ was significantly associated with HbA1c and HDL-C. In addition, we classified the study patients into three groups: 'morning type', 'neither type' and 'evening type' according to the sum of the MEQ score, and analyzed the difference between morning type (n = 32) and evening type (n = 11). We found that HbA1c, low-density lipoprotein cholesterol and PSQI of the morning type group were significantly lower than those of the evening type group. CONCLUSIONS: The present study suggests that 'eveningness' type male Japanese workers with type 2 diabetes suffer inadequate glycemic control.

Combination of the Framingham risk score and carotid intima-media thickness improves the prediction of cardiovascular events in patients with type 2 diabetes.

OBJECTIVE: The aim of this study was to investigate whether carotid intima-media thickness (IMT) and brachial-ankle pulse wave velocity (baPWV) add value to the Framingham risk score (FRS) in predicting the development of cardiovascular diseases (CVDs) in type 2 diabetic patients with a negative history of CVD. RESEARCH DESIGN AND METHODS: Type 2 diabetic patients (n = 783) were retrospectively recruited and followed for CVD. RESULTS: During a 5.4-year follow-up period, 85 incidences of CVD were recorded (10.9%). After adjustment for conventional arterial risk factors, multivariate analysis with the Cox proportional hazards model identified IMT, but not baPWV, as a significant determinant of CVD. In addition, the combination of FRS with IMT, but not with baPWV, improved the prediction of CVD. CONCLUSIONS: Carotid IMT is a significant predictor of CVD in asymptomatic type 2 diabetic patients, and the combination of FRS and IMT improves the prediction of CVD in these patients.

MicroRNA-223 expression in neutrophils in the early phase of secondary damage after spinal cord injury.

MicroRNA (miR)s are short non-coding RNAs that suppress the translation of target genes, and play an important role in gene regulation. Despite this prominence, there are few reports that refer to the expression of miRs after spinal cord injury (SCI). Previously, we reported on miR-223 expression after SCI in mice. The purpose of this study is to reveal the distribution of miR-223 and identify the cells that express miR-223 in the injured spinal cord. Quantitative polymerase chain reaction analysis revealed high expression of miR-223 at 12h after SCI. Double staining of in situ hybridization and immunohistochemistry showed that the signals of miR-223 merged with Gr-1 positive neutrophils. Our data indicate that miR-223 might regulate neutrophils in the early phase after SCI.

Assessment of central motor conduction time in the diagnosis of compressive thoracic myelopathy.

STUDY DESIGN: Prospective clinical study. OBJECTIVE: The objective of this study was to investigate central motor conduction time (CMCT) values in patients with compressive thoracic myelopathy (CTM) and analyze its power to diagnose this condition. SUMMARY OF BACKGROUND DATA: CTM is rare and its diagnosis is often difficult, when other spinal disorders such as cervical or lumbar degenerative spondylosis supervene. Measurement of CMCT following transcranial magnetic stimulation is a useful means to evaluate the electrophysiological functions of the corticospinal tract; however, there are few reports describing CMCT values among patients with CTM. METHODS: Motor-evoked potentials following transcranial magnetic stimulation, and compound muscle action potentials and F-waves following electrical stimulation in the ulnar and tibial nerves were measured from the abductor digiti minimi (ADM) and abductor hallucis (AH) muscles in 20 patients with CTM, 92 patients with compressive cervical myelopathy (CCM), and 18 control subjects. The CMCT detected from the ADM (CMCT-ADM), the AH (CMCT-AH), and the CMCT-ADM/AH ratio (CMCT-ADM/CMCT-AH) were calculated. RESULTS: The CMCT-AHs in patients with CTM were significantly longer than in control subjects, although there were no significant differences in the CMCT-ADMs. In contrast, both the CMCT-ADMs and CMCT-AHs in the CCM group were significantly longer than those of the control group. The CMCT-ADM/AH ratios in the CTM group were significantly lower than those of the other groups. Among the CTM and CCM groups, when the cutoff point of the CMCT-ADM/AH ratio was set at equal to or lower than 0.52, i.e., the mean CMCT-ADM/AH ratio in the control group, the odds ratio for CTM was 68.4 (95% confidence interval: 8.62-543; P < 0.001). CONCLUSION: Our data showed a significant pattern of CMCT parameters and low CMCT-ADM/AH ratios in patients with CTM. The measurement of CMCT is valuable as a noninvasive technique for screening patients with CTM or CCM before magnetic resonance imaging.

CD133+ cells from human umbilical cord blood reduce cortical damage and promote axonal growth in neonatal rat organ co-cultures exposed to hypoxia.

To evaluate the effect of CD133(+) cells (endothelial progenitor cells) on the hypoxia-induced suppression of axonal growth of cortical neurons and the destruction of blood vessels (endothelial cells), we used anterograde axonal tracing and immunofluorescence in organ co-cultures of the cortex and the spinal cord from 3-day-old neonatal rats. CD133(+) cells prepared from human umbilical cord blood were added to the organ co-cultures after hypoxic insult, and axonal growth, vascular damage and apoptosis were evaluated. Anterograde axonal tracing with 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate was used to analyze axonal projections from the cortex to the spinal cord. Immunolabeling co-cultured tissues of the cortex and the spinal cord were used to investigate the effect of CD133(+) cells on the survival of blood vessels and apoptosis in the brain cortex. Hypoxia remarkably suppressed axonal growth in organ co-cultures of the cortex and the spinal cord, and this suppression was significantly restored by the addition of CD133(+) cells. CD133(+) cells also reduced the hypoxia-induced destruction of the cortical blood vessels and apoptosis. CD133(+) cells had protective effects on hypoxia-induced injury of neurons and blood vessels of the brain cortex in vitro. These results suggest that CD133(+) cell transplantation may be a possible therapeutic intervention for perinatal hypoxia-induced brain injury.

The effects of combining chondroitinase ABC and NEP1-40 on the corticospinal axon growth in organotypic co-cultures.

The area surrounding the injured spinal cord is a non-permissive milieu for axonal growth due to the inhibitory factors, especially chondroitin sulfate proteoglycan (CSPG) and Nogo. Recent studies have reported that chondroitinase ABC (ChABC) or Nogo-66(1-40) antagonist peptide (NEP1-40) promote axonal growth after spinal cord injury. But no study has addressed the effects on spinal cord injury of combining ChABC and NEP1-40. Previously, we described an organotypic co-culture system using the brain cortex and spinal cord from neonatal rats. In this study, we examined whether the combination of ChABC and NEP1-40 creates an action that promotes corticospinal axon growth in organotypic co-cultures. Organotypic co-cultures of brain and spinal cord were prepared from rats, and ChABC or NEP1-40 was delivered to them. To examine the effects of this combination these two drugs were applied together. We counted the number of labeled axons with DiI and assessed the immunoreactivity of CSPG and Nogo. Axonal growth was enhanced by infusing ChABC or NEP1-40 compared with that in the control group, whereas synergistic effects of combined administration of ChABC and NEP1-40 on axonal growth were not observed. There is a possibility that ChABC and NEP1-40 affect the same intracellular pathways and have no synergistic influence on axonal growth.

Quantitative assessment of myelopathy patients using motor evoked potentials produced by transcranial magnetic stimulation.

Motor evoked potentials (MEPs) study using transcranial magnetic stimulation (TMS) may give a functional assessment of corticospinal conduction. But there are no large studies on MEPs using TMS in myelopathy patients. The purpose of this study is to confirm the usefulness of MEPs for the assessment of the myelopathy and to investigate the use of MEPs using TMS as a screening tool for myelopathy. We measured the MEPs of 831 patients with symptoms and signs suggestive of myelopathy using TMS. The MEPs from the abductor digiti minimi (ADM) and abductor hallucis (AH) muscles were evoked by transcranial magnetic brain stimulation. Central motor conduction time (CMCT) is calculated by subtracting the peripheral conduction time from the MEP latency. Later, 349 patients had surgery for myelopathy (operative group) and 482 patients were treated conservatively (nonoperative group). CMCTs in the operative group and nonoperative group were assessed. MEPs were prolonged in 711 patients (86%) and CMCTs were prolonged in 493 patients (59%) compared with the control patients. CMCTs from the ADM and AH in the operative group were significantly more prolonged than that in the nonoperative group. All patients in the operative group showed prolongation of MEPs or CMCTs or multiphase of the MEP wave. MEP abnormalities are useful for an electrophysiological evaluation of myelopathy patients. Moreover, MEPs may be effective parameters in spinal pathology for deciding the operative treatment.

Clinical results of cervical myelopathy in patients older than 80 years of age: evaluation of spinal function with motor evoked potentials.

OBJECT: In this prospective analysis the authors describe the clinical results of surgical treatment in patients > 80 years of age in whom spinal function was evaluated with motor evoked potential (MEPs) monitoring. METHODS: The authors included 57 patients > 80 years of age who were suspected of having cervical myelopathy. The mean age of the patients was 83.0 years (range 80-90 years). The central motor conduction time (CMCT) was calculated from the latencies of the MEPs following transcranial magnetic stimulation and from M and F waves following peripheral nerve stimulation. RESULTS: Preoperative electrophysiological evaluation demonstrated significant elongation of CMCT or abnormalities in MEP waveforms in 37 patients (65%), and 35 patients of these underwent laminoplasty. In 30 patients cervical spondylotic myelopathy was diagnosed and 5 patients ossification of the posterior longitudinal ligament was diagnosed. The preoperative mean Japanese Orthopaedic Association Scale score was 8.6 (range 3-12.5) and the mean postoperative score was 12.6 (range 6-14.5) with an average recovery rate of 45% (range -21 to 100%). There were no major complications in any of the patients during the operative period and there were no cases of death resulting from operative intervention. CONCLUSIONS: Sufficient clinical results are expected even in patients with myelopathy who are older than 80 years of age, provided the patients are correctly selected by electrophysiological evaluation with MEPs and CMCT.