Dataset for clinical assessment of flexion-relaxation phenomenon

As reported in Table 1 (Supplementary Data) there are 25 case studies (12 female and 13 male) identified with an ID number belonging to two groups: 13 controls (subjects without low back pain) and 12 patients (subjects with low back pain). Data are acquired using a wireless body sensor network, as depicted in Fig.1 (Supplementary Data), and the flexion-extension test that is usually composed by 4 cycles (an appropriate number to evaluate the phenomenon). In each cycle the starting point is the "standing" position (called phase 1), then "flexion" movement (called phase 2), "full flexion" position (called phase 3) and "extension" movement (called phase 4) as can be seen in video example Vid.1 and Vid.2 (Supplementary Data). “IDx – Anamnesis.pdf” (Raw Data/IDx) identify physical condition, perceived pain and subject disability level acquired during the visit by specialized medical staff. Table 2 (Supplementary Data) summarize the perceived pain from all subjects during the time (a mean value typically perceived and values before/during/after the test) and it is useful to better understand the global physical condition during the analysis. "IDx - sEMG" file (Raw Data/IDx) contains raw sEMG data (sample frequency=2kHz): • Time series (s) -> sEMG reference time signal • sEMG1 (uV) -> sEMG left longissimus signal • sEMG2 (uV) -> sEMG right longissimus signal • sEMG3 (uV) -> sEMG left multifidus signal • sEMG4 (uV) -> sEMG right multifidus signal "IDx - Inertial" file (Raw Data/IDx) contains the inertial data (sample frequency=128Hz): • Time series (s) -> Inertial reference time signal • Gyroscope x (°/s) -> Angular velocity on the x axis • Gyroscope y (°/s) -> Angular velocity on the y axis • Gyroscope z (°/s) -> Angular velocity on the z axis • Acc x (g) -> Acceleration on the x axis • Acc y (g) -> Acceleration on the y axis • Acc z (g) -> Acceleration on the z axis • Magn x (G) -> Magnitude on the x • Magn y (G) -> Magnitude on the y • Magn z (G) -> Magnitude on the z

根据表1（补充数据），本数据集共包含25个案例研究（其中女性12例，男性13例），所有案例均分配有唯一识别编号，分为两组：13例对照组（无腰痛症状的受试者）与12例患者组（存在腰痛症状的受试者）。数据通过无线体域网（wireless body sensor network）采集，采集方案如图1（补充数据）所示，配套的屈伸测试通常包含4个循环周期（该周期数可有效评估目标生理现象）。每个测试循环均以“站立位”为起始点（记为阶段1），随后依次完成“屈曲动作”（阶段2）、“完全屈曲位”（阶段3）与“伸展动作”（阶段4），相关演示可参考补充数据中的视频示例Vid.1与Vid.2。"IDx – Anamnesis.pdf"（Raw Data/IDx）记录了由专业医护人员在问诊期间采集的受试者身体状况、主观疼痛感知与残疾程度。表2（补充数据）汇总了所有受试者在测试期间的疼痛感知情况（包含典型平均疼痛值，以及测试前、测试中与测试后的疼痛数值），该表有助于在分析阶段更好地理解受试者的整体身体状态。"IDx - sEMG"文件（Raw Data/IDx）包含原始表面肌电（surface electromyography, sEMG）数据，采样频率为2kHz，具体字段如下：
• 时间序列（s）：sEMG参考时间信号
• sEMG1 (uV)：左侧最长肌表面肌电信号
• sEMG2 (uV)：右侧最长肌表面肌电信号
• sEMG3 (uV)：左侧多裂肌表面肌电信号
• sEMG4 (uV)：右侧多裂肌表面肌电信号
"IDx - Inertial"文件（Raw Data/IDx）包含惯性传感数据，采样频率为128Hz，具体字段如下：
• 时间序列（s）：惯性参考时间信号
• 陀螺仪x轴角速度（°/s）：x轴方向角速度
• 陀螺仪y轴角速度（°/s）：y轴方向角速度
• 陀螺仪z轴角速度（°/s）：z轴方向角速度
• x轴加速度（g）：x轴方向加速度
• y轴加速度（g）：y轴方向加速度
• z轴加速度（g）：z轴方向加速度
• x轴磁场强度（G）：x轴方向磁场分量
• y轴磁场强度（G）：y轴方向磁场分量
• z轴磁场强度（G）：z轴方向磁场分量