Lumbar Tactile Acuity in Experimentally Induced Acute Low Back Pain
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 57
- 试验地点
- 1
- 主要终点
- Lumbar tactile acuity measured by two-point discrimination test (TPD).
研究概览
简要总结
The purpose of this study is to determine whether experimentally induced acute low back pain might lead to alteration in lumbar tactile acuity measured in region affected by pain compared to pain-free side and pain-free controls.
详细描述
Healthy male participants will be recruited at the Academy of Physical Education in Katowice. Each participant will be assessed only once. All participants will be asked to provide written informed consent for participation prior to the experimental procedure and will be naïve to the experimental hypothesis. The plan for this research project has been previously approved by the local bioethical committee.
Between-subject (real-injection, sham-injection and control group) and within-subject (assessment 1 versus assessment 2 and 3) design will be used for the purpose of this experiment. After the screening procedure and preparation phase, participants will be randomly assigned to one of three groups: control, saline injection or sham-injection. Groups will differ only in terms of the specific manipulation: the experimental group will receive intra-muscular saline injection, the sham-injection group will be stimulated by pinprick sensation produced by a PinPrick device. No manipulation will take place in the control group allowing to control for the learning effect. In fact, participants will be informed that the study includes only two branches so they can be assigned either to the group with pain evoked as a result of an injection or to the control group without any noxious stimuli. Not revealing the sham-injection condition will allow for comparison between nociceptive (injection) and non-nociceptive (sham-injection) condition.
Because no previous studies have investigated tactile acuity changes in acute low back pain, the sample size calculation was based on the data from our own systematic review and meta-analysis (Adamczyk et al., under review) and previous cross-sectional data among healthy controls (Adamczyk et al., 2016). Based on reported mean difference of 9.49mm between chronic low back pain patients and healthy controls and standard deviation of 9.90mm, a total sample size of 57 participants (19 per group) is required to detect a significant effect. Power calculation was performed for specific planned-comparison tests that were described in detailed under 'statistical analysis' section below. Calculation was performed in G*Power (G*Power 3.1.9.2 statistical software) with the alpha level set at =0.05 and 80% power.
Baseline differences in descriptive statistics will be analysed by one-way analysis of variance (ANOVA) with 'group' as the between-subject factor. Further statistical comparisons will be performed using a repeated-measures ANOVA design, with 'group' (real-injection, sham-injection, and control group) as between-subject factor and repeated measures (assessment 1, 2 and 3) as a within-subject factor. In order to test hypothesis on tactile acuity alteration during pain induction, F-tests will be followed by planned comparisons on data from assessment 1 versus assessment 2 in experimental group. To determine whether the magnitude of tactile acuity alteration has differed between the groups, planned comparisons will be performed on the difference in tactile acuity (assessment 1 vs. assessment 2) between real-injection and sham-injection group and between real-injection and control group. Bonferroni correction will be used for multiple planned comparisons. Forward, stepwise multiple regression will be performed to determine the degree to which tactile acuity change is predicted by either pain intensity or the size of its distribution. All the analyses will be conducted using the STATISTICA data analysis software, version 12 (StatSoft Inc., Tulsa, OK, USA). The level of significance will be set at p < 0.05.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Basic Science
- 盲法
- Double (Participant, Outcomes Assessor)
入排标准
- 年龄范围
- 18 Years 至 35 Years（Adult）
- 性别
- Male
- 接受健康志愿者
- 是
入选标准
- •Only participants with similar mechanical detection threshold (MDT) on both sides of the spine will be included.
排除标准
- •sex: female
- •age < 18 or > 35 years
- •laterality: left-handed
- •current pain experience
- •episodes of back pain lasting more than 24 hours within the previous one-month period
- •history of chronic pain, i.e. pain lasting more than one-month
- •comorbidities affecting the nervous system
- •cardio-vascular diseases
- •psychiatric illnesses
- •any disease requiring systematic drug consumption.
- •diagnosed hypersensitive reaction to saline solution
研究组 & 干预措施
Saline Injection
In the saline injection group, low back pain will be induced via 1.0 ml hypertonic (5% NaCl).
干预措施: Saline injection (Other)
Sham Injection
In the sham injection group, a real needle will be shown to the participants to imitate and produce the anticipation of a pain experience.
干预措施: Sham injection (Other)
Control Group
The control group will not receive any kind of pain or pinprick sensation.
结局指标
主要结局
Lumbar tactile acuity measured by two-point discrimination test (TPD).
时间窗: Measured an average 3 minutes after manipulation (e.g. saline injection).
Mechanical callipers will be delicately applied to the pre-marked axis until the very first blanching of the skin. Testing will be commenced with 0 mm between the two calliper's tips, and then the distance between them will be gradually increased until participants will able to verbally report that two points had been touched instead of one. Subsequently, the descending sequence will be applied until the perception of the two points disappeared.
次要结局
- Pain intensity measured behaviourally on a Numerical Rating Scale (NRS).(Pain intensity will be measured just after saline/sham injection and every 30 seconds after this time point up until 12 minutes.)
- Distribution of pain measured by estimating the diameter of the circle representing area affected by pain. Greater circle (diameter) will refer to the greater distribution of pain (larger body surface affected).(Pain distribution will be measured just after saline/sham injection and every 30 seconds after this time point up until 12 minutes.)
- Fear of pain measured on a Numerical Rating Scale (NRS).(Fear of pain measured only at baseline)
- Lumbar tactile acuity measured by point-to-point test (PTP).(PTP measured at baseline (1), an average 3 minutes after manipulation (2) (e.g. saline injection) and 12 minutes after manipulation (3))
- Lumbar tactile acuity measured by two-point estimation test (TPE)(PTP measured at baseline (1), an average 3 minutes after manipulation (2) (e.g. saline injection) and 12 minutes after manipulation (3))
研究者
Wacław Adamczyk
PhD candidate
The Jerzy Kukuczka Academy of Physical Education in Katowice