A longitudinal study of pain, personality, and brain plasticity following peripheral nerve injury

Abstract

We do not know precisely why pain develops and becomes chronic after peripheral nerve injury (PNI), but it is likely due to biological and psychological factors. Here, we tested the hypotheses that (1) high Pain Catastrophizing Scale (PCS) scores at the time of injury and repair are associated with pain and cold sensitivity after 1-year recovery and (2) insula gray matter changes reflect the course of injury and improvements over time. Ten patients with complete median and/or ulnar nerve transections and surgical repair were tested ∼3 weeks after surgical nerve repair (time 1) and ∼1 year later for 6 of the 10 patients (time 2). Patients and 10 age-/sex-matched healthy controls completed questionnaires that assessed pain (patients) and personality and underwent quantitative sensory testing and 3T MRI to assess cortical thickness. In patients, pain intensity and neuropathic pain correlated with pain catastrophizing. Time 1 pain catastrophizing trended toward predicting cold pain thresholds at time 2, and at time 1 cortical thickness of the right insula was reduced. At time 2, chronic pain was related to the time 1 pain-PCS relationship and cold sensitivity, pain catastrophizing correlated with cold pain threshold, and insula thickness reversed to control levels. This study highlights the interplay between personality, sensory function, and pain in patients following PNI and repair. The PCS-pain association suggests that a focus on affective or negative components of pain could render patients vulnerable to chronic pain. Cold sensitivity and structural insula changes may reflect altered thermosensory or sensorimotor awareness representations.

Inferring distinct mechanisms in the absence of subjective differences: Placebo and centrally acting analgesic underlie unique brain adaptations

“…An important question still lingering in the field is whether brain abnormalities specific to a pain condition renormalize after a treatment, and whether this renormalization is linked to significant analgesia. Several studies have shown reversibility in structural or functional properties for various treatment approaches and pain conditions (Cummiford et al, 2016;Goswami, Anastakis, Katz, & Davis, 2016;Gwilym et al, 2010;Seminowicz et al, 2011Seminowicz et al, , 2013. However, none of them has investigated unbiased whole brain structural and resting state functional reorganization in relation with original difference with controls.…”

Abnormal Local Brain Activity Beyond the Pain Matrix in Postherpetic Neuralgia Patients: A Resting-State Functional MRI Study

“…Although much of the brain imaging studies of PHN were conducted using fMRI, we should notice that mounting evidence indicated that NP resulted in or was accompanied by plastic change or structural abnormality in human (65)(66)(67)(68)(69) and murine (70,71) brains. Much of the plastic and structural alterations took place in pain-processing regions.…”

Treatment of Peroneal Nerve Injury with Sural Nerve Transplantation; Case Report and Evaluation of Surgical Technique

“…Aynı zamanda periferik sinir hasarı sonrası hastalarda kronik ağrı, kişilik değişikliği ve uyum sorunu gibi gündelik yaşama yansıyan sendromlar gelişmektedir. Bu durum hem hastada hem de çevresinde duygu bozukluğuna neden olmak da psikolojik sorunları da beraberinde getirmektedir (4) . Olgumuzda ve ailesinde de antidepresan ilaç kullanım öyküsü mevcuttu.…”

“…Postoperatif medikal tedavide öncelikle gabapentin, pregabalin, alfa-lipoik asit nöropatik ağrıyı engelleyip ve sinir rejenerasyonunu artırdığı için önerilmektedir (3,4,6) . İmmün supresif ilaçların ise bu tedavi modalitesinde yeri tartışmalıdır (2,5) .…”