Focal Vibration Alters Human Digital Sensory Nerve Action Potentials: A Pilot Study.

Introduction: We studied the impact of vibratory stimulation on the electrophysiological features of digital sensory nerve action potential (SNAP). Methods: The antidromic digit 3 SNAP was recorded in 19 healthy adults before, during, and after applying a vibration to either 3rd or 5th metacarpal phalangeal joint (MCPJ) at 60 Hz and amplitude of 2 mm. 100% supramaximal stimulus intensity was performed in 5 subjects (randomly selected from the 19 subjects) where the SNAP sizes were recorded. Results: The amplitude of digit 3 SNAP declined to 58.9 ± 8.6% when a vibration was applied to MCPJ digit 3. These impacts did not change by increasing the electrical stimulus intensity. The SNAP regained its baseline value immediately after the cessation of vibration stimulation. The magnitude of size reduction of digit 3 SNAP was less when vibration was moved to from MCPJ of digit 3 to MCPJ of digit 5. Discussion. The marked drop of the SNAP size during vibratory stimulation reflects the decreased responsiveness of Aß afferents to electrical stimulation, which deserve further investigation in the study of focal vibration in neurorehabilitation.

Exosome-Transported circRNA_0000253 Competitively Adsorbs MicroRNA-141-5p and Increases IDD.

The pathogenesis of intervertebral disc degeneration (IDD) is complex, and a better understanding of IDD pathogenesis may provide a better method for the treatment of IDD. Exosomes are 40-100 nm nanosized vesicles that are released from many cell types into the extracellular space. We speculated that exosome-transported circular RNAs (circRNAs) could regulate IDD. Exosomes from different degenerative grades were isolated and added to nucleus pulposus cells (NPCs), and indicators of proliferation and apoptosis were detected. Based on the previous circRNA microarray results, the top 10 circRNAs were selected. PCR was performed to determine the circRNA with the maximum upregulation. Competing endogenous RNA (ceRNA) analysis was carried out, and the sponged microRNA (miRNA) was identified. Further functional verification of the selected circRNA was carried out in vivo and in vitro. NPCs of different degenerative grades secreted exosomes, which could regulate IDD. circRNA_0000253 was selected as having the maximum upregulation in degenerative NPC exosomes. ceRNA analysis showed that circRNA_0000253 could adsorb miRNA-141-5p to downregulate SIRT1. circRNA_0000253 was confirmed to increase IDD by adsorbing miRNA-141-5p and downregulating SIRT1 in vivo and in vitro. Exosomal circRNA_0000253 owns the maximum upregulation in degenerative NPC exosomes and could promote IDD by adsorbing miRNA-141-5p and downregulating SIRT1.

The value of radiographic indexes in the diagnosis of discogenic low back pain: a retrospective analysis of imaging results.

To explore value of different radiographic indexes in the diagnosis of discogenic low back pain (LBP). A total number of 120 cases (60 patients diagnosed with discogenic LBP and 60 healthy people) were retrospectively analysed to identify factors in the diagnosis of discogenic LBP by using univariate and multivariate analyses. A receiver operating characteristic (ROC) curve was drew to show the predictive accuracy of the finally enrolled factors. Among all the included patients, 60 were strictly admitted in the discogenic LBP group while the other 60 were enrolled in the control group. Five results shows significant differences between discogenic LBP and control groups, including Cobb angle, lumbar stability, height of the disc, Modic change and High intense zone (HIZ) based on the results of univariate analysis; lumbar stability, Modic change and HIZ show high value in the diagnosis of lumbar discogenic pain based on the multivariate logistic analysis. The ROC curve shows that good diagnostic accuracy was obtained from the enrolled diagnostic factors including lumbar stability (Angular motion, more than 14.35°), Modic change and HIZ.

Risk Factors for Surgical Results of Hirayama Disease: A Retrospective Analysis of a Large Cohort.

OBJECTIVE: To explore risk factors affecting surgical results of Hirayama disease. METHODS: A retrospective analysis of 210 patients was performed to identify risk factors affecting surgical results of Hirayama disease by using univariate and multivariate analyses. A receiver operating characteristic curve and area under the curve were applied to evaluate the significant results of the multivariate analysis and the optimal reference value. RESULTS: The mean follow-up period was 27.3 months (range, 14-45 months), and 194 patients with clinical and radiographic data completed the final follow-up. Multivariate analysis identified age of patients (cutoff value 22.5 years), duration of the disease (cutoff value 33 months), physiologic reflex, and pathologic reflex as independent risk factors for surgical results of Hirayama disease. The receiver operating characteristic curve analysis and area under the curve showed that good reference value was obtained for the risk factors. CONCLUSIONS: Age of patient, duration of the disease, physiologic reflex, and pathologic reflex are the main risk factors affecting surgical results of Hirayama disease. Receiver operating characteristic analysis shows that good reference value was obtained for the risk factors.

Electrophysiological differences between Hirayama disease, amyotrophic lateral sclerosis and cervical spondylotic amyotrophy.

BACKGROUND: Hirayama disease (HD), amyotrophic lateral sclerosis (ALS) or cervical spondylotic amyotrophy (CSA) may result in atrophy of intrinsic hand and forearm muscles. The incidence of HD is low, and it is rarely encountered in the clinical setting. Consequently, HD is often misdiagnosed as ALS or CSA. It is important to differentiate these diseases because HD is caused by a benign focal lesion that is limited to the upper limbs. METHODS: The thenar and hypothenar compound muscle action potential (CMAP) amplitude of the upper limbs of 100 HD, 97 ALS and 32 CSA cases were reviewed; 35 healthy individuals were included as controls. Seventy-eight percent, 38% and 69% of patients with HD, ALS or CSA had unilateral involvement; the remaining patients were affected bilaterally. Thenar and hypothenar CMAP amplitude evoked by ulnar stimulation was compared with CMAP evoked by median stimulation. RESULTS: The ulnar/median CMAP ratio was found to be lower in HD (0.55 ± 0.41, P<0.0001), higher in ALS (2.28 ± 1.15, P<0.0001) and no different in CSA (1.21 ± 0.53, P>0.05) compared with the normal range from previous studies (0.89-1.60) and with the healthy controls (1.15 ± 0.23). Conduction velocities of the sensory and motor nerves, the amplitude of the sensory nerve action potential, and the CMAP amplitude of the unaffected limb were all normal. CONCLUSIONS: The hand muscles were differentially affected between patients with HD, ALS and CSA. The ulnar/median CMAP ratio could be used to distinguish these three diseases.

Potential advantages of the H-reflex of the biceps femoris-long head in documenting S1 radiculopathy.

PURPOSE: A novel H-reflex method using the biceps femoris-long head (BF-LH) was investigated to collect the normative data for this reflex arc and assess its clinical utility for S1 radiculopathy evaluation. Comparability with conventional tibial and Sol H-reflex findings was also determined. METHODS: BF-LH H-reflexes were recorded using surface electrodes to S1-root stimulation in 43 unilateral S1 radiculopathy patients (radiculopathy group) and 34 normal subjects (control group) from March 2009 to December 2011. H-M interval and peak-to-peak amplitudes were measured. The BF-LH H-reflex and the H-reflex from the soleus muscle (Sol H-reflex) to both tibial nerve stimulation (tibial H-reflex) and S1-root stimulation were used and compared for application in S1 radiculopathy evaluation. RESULTS: BF-LH H-reflexes were reliably recorded for all control group subjects. Abnormal BF-LH H-reflexes were recorded for 40 (93.0%) radiculopathy group patients in the involved extremity, and abnormal involved side tibial H-reflexes and Sol H-reflexes were recorded in 31 (72.1%) and 41 (95.3%) radiculopathy group patients, respectively. The BF-LH H-reflex exhibited significantly higher sensitivity for evaluation of S1 radiculopathy, accurate in 40 (93.0%) radiculopathy group patients, than that provided by the conventional tibial H-reflex of only 31 (72.1%) (P < 0.05). CONCLUSIONS: The BF-LH H-reflex is a highly sensitive and reliable clinical tool for evaluation of the S1 spinal reflex pathway in radiculopathy that is distinct from the Sol H-reflex and conventional tibial H-reflex arcs.

Proximally evoked soleus H-reflex to S1 nerve root stimulation in sensory neuronopathies (ganglionopathies).

INTRODUCTION: Sensory neuronopathy (SNN) mimics distal sensory axonopathy. The conventional H-reflex elicited by tibial nerve stimulation (tibial H-reflex) is usually abnormal in both conditions. We evaluated the proximally evoked soleus H-reflex in response to S1 nerve root stimulation (S1 foramen H-reflex) in SNN. METHODS: Eleven patients with SNN and 6 with distal sensory axonopathy were studied. Tibial and S1 foramen H-reflexes were performed bilaterally in each patient. RESULTS: Tibial and S1 foramen H-reflexes were absent bilaterally in all patients with SNN. In the patients with distal sensory axonopathy, tibial H-reflexes were absent in 4 and demonstrated prolonged latencies in 2, but S1 foramen H-reflexes were normal. CONCLUSIONS: Characteristic absence of the H-reflex after both proximal and distal stimulation reflects primary loss of dorsal root ganglion (DRG) neurons and the distinct non-length-dependent impairment of sensory nerve fibers in SNN.