Minafra Paolo, Alviti Federica, Giovagnorio Raffaella, Cantisani Vito, Mazzoni Gianni
Società Polisportiva Ars et Labor Football Club, Ferrara, Italy.
Department of Anatomy, Histology, Forensic Medicine, and Orthopedics, Board of Physical Medicine and Rehabilitation.
J Ultrasound Med. 2020 Nov;39(11):2195-2200. doi: 10.1002/jum.15330. Epub 2020 May 11.
The myotendinous junction (MTJ) represents a specialized anatomic region through which the contractile strength is transmitted from the muscle to the tendon. The integrity of this region is essential to permit force transmission and to optimize energy expenditure during walking, running, and globally for human movement. We evaluated the MTJ with shear wave elastography to assess its elasticity variation during a functional test.
Forty professional soccer players were enrolled in the study. Shear wave elastography was performed at the level of the medial gastrocnemius MTJ both in a resting position and during a standing calf rise position to assess functional contraction.
All 40 participants were male, aged between 18 and 38 years (mean age, 25 years). The results of the elastographic study showed mean stiffness values ± SD of 4.19 ± 0.86 m/s for the right medial gastrocnemius and 4.20 ± 0.87 m/s for the left medial gastrocnemius with the muscle relaxed. During contraction, the stiffness values were 8.33 ± 0.5 m/s for the right medial gastrocnemius and 8.30 ± 0.48 m/s for the left medial gastrocnemius.
Our study showed an increase of stiffness at the level of the MTJ during muscle contraction. This result is in line with the physiologic stiffening of the MTJ to resist the high level of force applied during muscle contraction. Shear wave elastography could be a useful method to assess the characteristics of the MTJ under both physiologic and pathologic conditions.
肌腱结合部（MTJ）是一个特殊的解剖区域，收缩力通过该区域从肌肉传递至肌腱。该区域的完整性对于在行走、跑步及整体人类运动过程中实现力的传递和优化能量消耗至关重要。我们采用剪切波弹性成像技术评估MTJ在功能测试期间的弹性变化。
40名职业足球运动员参与本研究。在休息位及站立位小腿抬高时，对腓肠肌内侧头MTJ水平进行剪切波弹性成像检查，以评估功能收缩情况。
40名参与者均为男性，年龄在18至38岁之间（平均年龄25岁）。弹性成像研究结果显示，肌肉放松时，右侧腓肠肌内侧头的平均硬度值±标准差为4.19±0.86m/s，左侧为4.20±0.87m/s。收缩时，右侧腓肠肌内侧头的硬度值为8.33±0.5m/s，左侧为8.30±0.48m/s。
我们的研究表明，肌肉收缩时MTJ水平的硬度增加。这一结果与MTJ生理上的变硬以抵抗肌肉收缩时所施加的高水平力相符。剪切波弹性成像可能是一种评估生理和病理条件下MTJ特征的有用方法。
