Low Back Pain - Disentangling Trait-Like and State-Like Alterations
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 105
- 试验地点
- 2
- 主要终点
- Mechanical Detection Threshold (MDT)
研究概览
简要总结
The primary goal of this study is to investigate whether different alterations observed in patients with non-specific episodic low back pain (compared to healthy volunteers), detected using several assessments: psychophysical and neurophysiological testing, imaging, and blood sampling, are dependent or independent of the presence and type of pain experienced at the time of investigation.
详细描述
The study consists of three visits (healthy volunteers will only have one pain-free visit), in which patients will be tested in a different "pain state" at each visit:
- Pain-free visit: will be carried out when the patients have no or little (Numerical Pain Rating Scale (NPRS) </= 2/10) clinical pain.
- Clinically relevant Low Back Pain visit: will be carried out with patients experiencing a low back pain episode with an intensity of 3/10 or more on the NPRS.
- Experimental pain / Clinically irrelevant pain visit: will be carried out with the application of a high concentration (8%) Qutenza® capsaicin patch at the arm.
Each of the visits will consist of psychophysical testing, neurophysiological assessement of sweat activity in response to pain, brain resting state magnetic resonance imaging and magnetic resonance spectroscopy. Additionally, and depending on the type of session, a lumbar spine magnetic resonance image (only pain-free session, as characterization) and a blood sample (only pain free and low back pain visit) will be performed.
研究设计
- 研究类型
- Observational
- 观察模型
- Case Control
- 时间视角
- Cross Sectional
入排标准
- 年龄范围
- 18 Years 至 70 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •German or English proficiency
- •Informed consent
- •Low back pain for more than 3 months
- •Low back pain clinically not attributable to "red flags" (e.g. infection, fractures, inflammation)
- •Fluctuating course of pain (with on and off pain periods).
排除标准
- •(applicable to both groups):
- •Inability to give informed consent / follow study instructions (e.g. due to language problems)
- •Major medical or psychiatric condition. E.g. severe heart disease, diabetes, autoimmune disorders, rheumatic disorders, major depressive disorder, etc.
- •Symptomatic radiculopathy, manifested through motor and/or sensory deficits / or signs of nerve root involvement on lumbar MRI.
- •Back operation
- •BMI > 30
- •Pregnancy
结局指标
主要结局
Mechanical Detection Threshold (MDT)
时间窗: 1 - 6 months
A reduced psychophysical QST battery will be performed in 3 body areas: most painful (MP), adjacent to MP, and a control area. MDT will be assessed with Von Frey filaments applied to the skin (mN). Subject reports when tactile input is detected.
Mechanical Pain Threshold (MPT)
时间窗: 1 - 6 months
A reduced psychophysical QST battery will be performed in 3 body areas: most painful (MP), adjacent to MP, and a control area. MPT will be assessed with pin-pricks (mN) applied to the skin. Subject reports when the stimulus feels sharp or blunt.
Conditioned Pain Modulation (CPM)
时间窗: 1 - 6 months
CPM measures the modulation of a noxious test stimulus by another noxious conditioning stimulus applied at a remote body region. In this study, test stimuli of different modalities (pressure, superficial mechanical, heat or electrical stimuli) will be applied at different body regions before and after or before, during and after a cold water bath or neutral water bath (hand immersion) as conditioning stimulus. Changes in test stimuli read-outs (during-before or after-before) will serve as CPM measure. Negative changes represent inhibitory, positive changes facilitatory CPM effects. For all test stimuli read-outs, CPM effects will be expressed as percentage changes. Test stimuli read-outs include: pain ratings on a scale of 0: no pain, to 100: most intense pain; perception thresholds and pain thresholds (in kg for pressure).
Mechanical Pain Sensitivity (MPS)
时间窗: 1 - 6 months
A reduced psychophysical QST battery will be performed in 3 body areas: most painful (MP), adjacent to MP, and a control area. MPS will be assessed with pin-pricks and Q-tip, cotton swab, and brush applied to the skin. Subjects rate stimuli on scale of 0-100. In our protocol only 3 blocks.
Wind-Up Ratio (WUR)
时间窗: 1 - 6 months
A reduced psychophysical QST battery will be performed in 3 body areas: most painful (MP), adjacent to MP, and a control area. WUR will be assessed with a pin-prick, which is applied 10 times in 10 seconds. Subjects rate the series on scale of 0-100. In our protocol, only 3 series.
Vibration Detection Threshold (VDT)
时间窗: 1 - 6 months
A reduced psychophysical QST battery will be performed in 3 body areas: most painful (MP), adjacent to MP, and a control area. VDT will be assessed with a tuning fork applied to a bony prominence. Subject reports when the vibration can't be felt anymore.
Pressure Pain Threshold (PPT):
时间窗: 1 - 6 months
A reduced psychophysical QST battery will be performed in 3 body areas: most painful (MP), adjacent to MP, and a control area. PPT will be assessed with an algometer (kg), applied to a muscle. Subject reports when pressure becomes painful.
Sympathetic Skin Responses (SSRs)
时间窗: 1 - 6 months
Neurophysiological assessement of sweat activity in response to pain will be recorded with cap electrodes located at the hand. Painful heat stimulation will be applied with a thermode of the Pathway Medoc System. A train of 15 heat stimuli, with an inter-stimulus interval of 13-17 seconds, will be applied. The thermode baseline temperature will be 42ºC and during the stimulation the temperature will quickly ramp up to 52 ºC. Subjects are asked to rate the perception of the stimulus using a pain scale of 0-100. This procedure will be done two times: one at the most painful area of the patients, and the corresponding body area in the matched healthy volunteer, and at the volar forearm as a control pain-free area. This readout is a proxy for sympathetic nervous system activity.
Brain resting state Magnetic Resonance Imaging (rsMRI)
时间窗: 1 - 6 months
Measure of the brain's spontaneous activity acquired during resting state using a 7T Siemens scanner.
Lumbar Magnetic Resonance Imaging
时间窗: 1 - 6 months
Structural resonance image of lumbar spine section acquired using a 3T Siemens scanner.
Brain Magnetic Resonance Spectroscopy (MRS)
时间窗: 1 - 6 months
Imaging method that allows the detection of concentration of certain metabolites in the brain. This data will be acquired using a 3T Phillips scanner.
Blood Sample
时间窗: 1 - 6 months
Blood sample of approximately 14 ml will be drawn, in a total of 3 tubes: PAXGene blood RNA tube, Serum tube, and K2 EDTA tube. This will allow analysis of inflammatory molecules (i.e. cytokines) and cell concentrations (i.e. immune cells).
次要结局
- Anxiety and Depression(1 - 6 months)
- Pain Catastrophizing(1 - 6 months)
- Pain Sensitivity(1 - 6 months)
- Pain Self Efficacy(1 - 6 months)
- Back Awareness(1 - 6 months)
- Central sensitization(1 - 6 months)
- Neuropathic Pain(1 - 6 months)
- Widespread Pain Index (WPI)(1 - 6 months)
- Disability(1 - 6 months)
- Pain Extent(1 - 6 months)
- Symptom Severity Scale (SSS)(1 - 6 months)
研究者
Schweinhardt Petra
Prof. Dr. Med. PhD
Balgrist University Hospital