Jessica Pingel, Institute of Sports Medicine, University of Copenhagen, Bispebjerg Bakke 23, Building 8, 1st Floor, DK-2400 Copenhagen, Denmark.
Am J Sports Med. 2013 Oct;41(10):2400-8. doi: 10.1177/0363546513498988. Epub 2013 Aug 12.
Achilles tendinopathy (AT) is initiated asymptomatically and is therefore often discovered at a very late stage.
To elucidate whether the microvascular volume (MV) of the Achilles tendon is elevated in patients with AT compared with healthy controls during pre-exercise rest, after acute exercise, and 24 hours after exercise. Additionally, this study investigated the muscle activation pattern of the gastrocnemius muscle and the relative elasticity of the Achilles tendon during a 1-hour treadmill run in healthy patients and in patients with AT.
Controlled laboratory study.
Real-time harmonic contrast-enhanced ultrasound (CEU) measurements of the MV of the Achilles tendon were taken in 18 volunteers (9 patients with AT, 9 healthy controls). The CEU analyses were conducted before exercise, immediately after a 1-hour treadmill run, and 24 hours after exercise. Surface electromyography (EMG) signals of the gastrocnemius were recorded continuously during the 1-hour treadmill run.
In both the controls and the patients with AT, the MV of the Achilles tendon was increased after exercise as compared with before exercise (P < .005). Additionally, the MV signal was significantly larger in the patients with AT before, immediately after, and 24 hours after the running exercise compared with values in healthy controls (P < .0001). The muscle activation pattern differed in patients with AT compared with controls in that controls had increased EMG amplitudes at the end of the 1-hour treadmill run in the medial and lateral gastrocnemius (P < .0001). Moreover, patients with AT had approximately 15% less elastic Achilles tendons at the beginning of the 1-hour treadmill run, a condition that did not change because of exercise.
Acute exercise increases the MV of the Achilles tendon in healthy patients and patients with AT in a similar manner. However, patients with AT have a significantly larger MV at all time points compared with healthy patients, supporting the hypothesis that microvascular changes may be involved in the pathogenesis of tendinopathy.
This study underlines that tendon flexibility is altered in patients with AT and that CEU is a promising tool to establish the early diagnosis of this condition.
跟腱病（AT）是无症状起始的，因此通常在非常晚期才被发现。
阐明在运动前休息、急性运动后和运动后 24 小时，与健康对照组相比，患有 AT 的患者的跟腱微血管容积（MV）是否升高。此外，本研究还在健康患者和 AT 患者中，在 1 小时跑步机跑步期间，调查了比目鱼肌的肌肉激活模式和跟腱的相对弹性。
对照实验室研究。
使用实时谐波对比增强超声（CEU）测量 18 名志愿者（9 名 AT 患者，9 名健康对照组）的跟腱 MV。CEU 分析在运动前、1 小时跑步机跑步后即刻和运动后 24 小时进行。在 1 小时跑步机跑步期间连续记录比目鱼肌的表面肌电图（EMG）信号。
在对照组和 AT 患者中，跟腱 MV 在运动后均高于运动前（P <.005）。此外，与健康对照组相比，AT 患者在跑步运动前、后即刻和后 24 小时，MV 信号显著更大（P <.0001）。与对照组相比，AT 患者的肌肉激活模式存在差异，在 1 小时跑步机跑步结束时，对照组的内侧和外侧比目鱼肌的 EMG 幅度增加（P <.0001）。此外，AT 患者在 1 小时跑步机跑步开始时的跟腱弹性约低 15%，但由于运动而没有改变。
急性运动以相似的方式增加健康患者和 AT 患者的跟腱 MV。然而，与健康患者相比，AT 患者在所有时间点的 MV 均显著更大，支持微血管变化可能参与跟腱病发病机制的假说。
本研究强调了 AT 患者的跟腱柔韧性发生改变，并且 CEU 是确立这种疾病早期诊断的有前途的工具。
