Systemic ATP infusion improves spontaneous pain and tactile allodynia,but not tactile hypesthesia,in patients with postherpetic neuralgia

Purpose Activation of purinoceptors may improve neuropathic pain. Accordingly, the effects of systemic ATP infusion were assessed in patients with postherpetic neuralgia (PHN).Methods Eight patients with PHN lasting over 3 months were enrolled. Initially, patients received the vehicle (20% dextrose) or ATP (at a dose of 1mg·kg^–1 in 20% dextrose) infused intravenously for 60min on two separate occasions in a single-blinded manner. The levels of spontaneous continuous pain, paroxysmal pain, and tactile allodynia were assessed by a visual analogue scale (VAS), and tactile hypesthesia was assessed by Semmes-Weinstein monofilament before and after infusion. Subsequently, the eight patients received an ATP infusion (1mg·kg^–1 in 20% dextrose) once a week for 5–12 weeks in an open-label manner, and changes in the above parameters were assessed.Results In the initial study, VAS for spontaneous continuous pain and tactile allodynia decreased significantly with ATP infusion but not with placebo infusion. After repeated ATP infusions for 5–12 weeks, the median VAS for spontaneous continuous pain, paroxysmal pain, and tactile allodynia decreased significantly from 32.1 to 13.0, from 46.9 to 17.5, and from 49.5 to 15.6 respectively. However tactile hypesthesia did not improve significantly.Conclusion This study demonstrated that repetitive intravenous ATP infusion could improve spontaneous continuous pain and paroxysmal pain, as well as improving tactile allodynia, but did not influence tactile hypesthesia.     

Psychogenic disorders in neurology: frequency and clinical spectrum

Among 4470 consecutive neurological inpatients presenting "with typical neurological symptoms" 405 (9%) were found to have psychogenic rather than neurological dysfunction of the nervous system as the primary cause of admission. This probably represents a conservative figure, since secondary and minor pseudoneurological symptoms were not included. Retrospective analysis of these cases showed that pain was the most common psychogenic symptom, followed by motor symptoms (in particular stance and gait disturbances), dizziness, psychogenic seizures, sensory symptoms, and visual dysfunction. Unilateral motor and sensory symptoms were equally distributed to the left and right side of the body. Psychiatric abnormalities in these patients were heterogenous. Depressive syndromes were most common (38%), whereas hysterical features were less frequent than expected (9%). On discharge, improvement was significantly better for patients with recent onset of symptoms (2 weeks or less) than for those with longstanding disturbances. Short-term outcome was best for motor symptoms and worst for pain. Improvement was independent of psychiatric findings, coexistence of a neurological disease, age, and sex.     

An Anatomical Study to the Branching Pattern of the Posterior Interosseous Nerve on the Dorsal Side of the Hand

Partial denervation of the wrist can benefit patients with chronic wrist pain. A complication of partial denervation is loss of proprioception and hypesthesia on the dorsal side of the hand. Our aim is to evaluate whether the sensory branches of the posterior interosseous nerve could contribute to the loss of proprioception and sensation. The branching pattern of the posterior interosseous nerve was studied in 20 cadaveric hands. The terminal branches of the posterior interosseous nerve reached the metacarpophalangeal joints in three specimens (15%), the midshaft of the metacarpals in three specimens (15%), carpometacarpal joints in 11 specimens (55%), and the scapholunate joint in three specimens (15%). The finding that terminal branches of the posterior interosseous nerve can reach the metacarpals and the metacarpophalangeal joints indicates that the posterior nerve may contribute to the proprioception and sensation of the dorsal side of the hand. Clin. Anat., 33:678–682, 2020. © 2019 Wiley Periodicals, Inc.     

Erectile dysfunction after a long-distance cycling event: associations with bicycle characteristics

PURPOSE: We conducted a prospective cohort study to examine the relationship between bicycle characteristics and the occurrence of erectile dysfunction. MATERIALS AND METHODS: Subjects consisted of 463 cyclists completing a cycling event of at least 320 km who were free of erectile dysfunction before their event. RESULTS: The cumulative incidence of erectile dysfunction after the ride was 4.2% (95% confidence interval [CI] 2.4%-6.8%) and 1.8% (95% CI 0.7%-3.8%) 1 week and 1 month after the event, respectively. Bicycle characteristics associated with an increased risk of erectile dysfunction included a mountain bicycle compared with a road bicycle (risk ratio [RR] 4.1, 95% CI 1.6-12.5), and the relative height of the handlebars parallel with or higher than the saddle compared with the relative handlebar height lower than the saddle (RR 3.0, 95% CI 1.1-9.3). Perineal numbness during the ride was experienced by 31% of the cyclists and was associated with erectile dysfunction (RR 4.4, 95% CI 1.6-12.7). Saddle cutouts were associated with an increased risk of erectile dysfunction among those who experienced numbness (RR 6.0, 95% CI 1.3-27.1), but the association was reversed among those who did not report numbness (RR 0.3, 95% CI 0.0-2.5). CONCLUSIONS: If the associations described are causal, then cyclists on a long-distance ride may be able to decrease the risk of erectile dysfunction by riding a road bicycle instead of a mountain bicycle, keeping handlebar height lower than saddle height and using a saddle without a cutout if perineal numbness is experienced.     

静息态fMRI观察电刺激诱发肢体持续麻木感

目的 采用静息态fMRI（rs-fMRI）比率低频振幅（fALFF）法检测电刺激诱发肢体持续麻木感时脑功能变化，探讨持续性麻木相关脑机制。方法 对21名健康成人分别在有无电刺激条件下行rs-fMRI，嘱其对同一脉冲电刺激所致麻木感进行强度评分。以fALFF算法分析有无电刺激下rs-fMRI数据，获得存在显著差异脑区；对电刺激下脑fALFF与个体麻木感强度评分进行相关性分析。结果 电刺激下fALFF显著增强脑区包括额叶内侧皮质、前扣带回、两侧颞中回、两侧颞下回和右侧颞极（P均<0.05，FDR校正）；显著减弱脑区包括楔前叶/后扣带回、右侧小脑（P均<0.05，FDR校正）。电刺激下fALFF与个体麻木感评分显著正相关脑区则包括楔前叶/后扣带回和左侧颞中回（P均<0.05，FDR校正）显著负相关脑区为右侧额极和左侧颞下回（P均<0.05，FDR校正）。结论 电刺诱发肢体持续麻木感涉及感觉运动、情绪、认知及默认网络相关脑区；楔前叶/后扣带回、颞叶及额叶部分脑区与个体麻木程度显著相关。     

基于分数低频振幅观察长时程电刺激诱发健康人肢体麻木后脑功能变化

目的 利用静息态功能MRI(rs-fMRI)分数低频振幅（fALFF）观察长时程电刺激（LTES）诱发健康人肢体麻木感后不同脑区功能变化。方法 前瞻性对27名健康人以LTES诱发单侧肢体麻木感,每日1次、每次30 min,持续1周;分别于开始刺激前日及末次刺激次日采集脑rs-fMRI,并于予5 min短时程电刺激后要求受试者采用视觉模拟评分法（VAS）对麻木感进行评分。比较LTES前、后各脑区fALFF,针对存在显著差异脑区分析其fALFF值变化及其差值与VAS评分差值的相关性。结果LTES后双侧顶上小叶、右侧颞中回、左侧海马旁回及右侧缘上回fALFF值降低,而双侧伏隔核、右侧中央后回、左侧小脑及右侧壳核fALFF值升高（P均<0.05）。LTES前、后左侧顶上小叶fALFF差值与VAS评分差值呈负相关（r=-0.422,P=0.029）。结论 LTES所诱发的肢体麻木感涉及感觉运动皮层及情绪等相关脑区,尤以左侧顶上小叶最为重要。