Transcranial magnetic stimulation (TMS) is used to investigate corticomotor neurophysiology associated with functional recovery in individuals with spinal cord injury (SCI). There is insufficient evidence about test–retest measurement properties of TMS in SCI. Therefore, we investigated test–retest agreement and reliability of TMS metrics representing corticomotor excitability, output, gain, map (representation), and inhibition in individuals with cervical SCI. We collected TMS metrics from biceps and triceps muscles because of the relevance of this proximal muscle pair to the cervical SCI population. Twelve individuals with chronic C3–C6 SCI participated in two TMS sessions separated by ≥ 2 weeks. Measurement agreement was evaluated using t tests, Bland–Altman limits of agreement and relative standard error of measurement (SEM%), while reliability was investigated using intra-class correlation coefficient (ICC) and concordance correlation coefficient (CCC). We calculated the smallest detectable change for all TMS metrics. All TMS metrics except antero-posterior map coordinates and corticomotor inhibition were in agreement upon repeated measurement though limits of agreement were generally large. Measures of corticomotor excitability, output and medio-lateral map coordinates had superior agreement (SEM% < 10). Metrics representing corticomotor excitability, output, and inhibition had good-to-excellent reliability (ICC/CCC > 0.75). The smallest detectable change for TMS metrics was generally high for a single individual, but this value reduced substantially with increase in sample size. We recommend use of corticomotor excitability and recruitment curve area owing to their superior measurement properties. A modest group size (20 or above) yields more stable measurements, which may favor use of TMS metrics in group level modulation after SCI.

经颅磁刺激 (TMS) 用于研究与脊髓损伤 (SCI) 个体功能恢复相关的皮质运动神经生理学。关于 SCI 中 TMS 的测试-再测试测量特性的证据不足。因此，我们研究了代表颈椎 SCI 患者皮质运动兴奋性、输出、增益、映射（表示）和抑制的 TMS 指标的重测一致性和可靠性。我们从二头肌和三头肌中收集了 TMS 指标，因为这对近端肌肉与颈椎 SCI 人群的相关性。12 名慢性 C3-C6 SCI 患者参加了两个间隔≥2 周的 TMS 会议。使用t评估测量一致性测试、Bland-Altman 一致性限和测量的相对标准误差 (SEM%)，而可靠性则使用类内相关系数 (ICC) 和一致性相关系数 (CCC) 进行研究。我们计算了所有 TMS 指标的最小可检测变化。除了前后映射坐标和皮质运动抑制外，所有 TMS 指标都在重复测量后一致，尽管一致的限制通常很大。皮质运动兴奋性、输出和中间-外侧地图坐标的测量具有优异的一致性（SEM% < 10）。代表皮质运动兴奋性、输出和抑制的指标具有良好到优秀的可靠性（ICC/CCC > 0.75）。对于单个个体，TMS 指标的最小可检测变化通常很高，但这个值随着样本量的增加而大幅降低。我们建议使用皮质运动兴奋性和募集曲线面积，因为它们具有优越的测量特性。适度的组大小（20 或以上）产生更稳定的测量，这可能有利于在 SCI 后在组级调制中使用 TMS 指标。