Letafatkar Amir, Mantashloo Zahed, Moradi Mohsen
Faculty of Physical Education and Sport Sciences, Kharazmi University, Tehran, Iran.
Gait Posture. 2018 Sep;65:256-261. doi: 10.1016/j.gaitpost.2018.08.001. Epub 2018 Aug 3.
Knee muscles activity changes from Genu Varum deformity(GVD), may cause this individual more exposed to lower extremity injuries especially in high-risk activities like landing.
The aim of this study was to compare the activity of the lower limb stabilizer muscles during jump-landing and time to stabilization(TTS) in subjects with and without GVD.
A total of 44 men (group 1, with GVD n = 22 and group 2, without GVD n = 22); with mean age = 17.6 ± 3.12 years, height = 178.2 ± 5.39 cm, mass = 80.39 ± 8.3 kg) participated in this study. Subjects were asked to do a jump-landing task and Quadratus Lumborum(QL), Gluteus Maximus(GMax), Gluteus Medius(GMed), Biceps Femoris (BF), Semitendinosus, and Medial Gastrocnemius(MG) muscles activity was recorded. Also, changes in the amount of ground reaction force(GRF) were used to an indicator for TTS.
Our results showed that subjects with GVD had increased QL activity before(P = 0.008) and after(P = 0.017) landing. But, these subjects had a decreased activity of GMed compared to the healthy ones before(P = 0.033) and after(P = 0.005) landing. but there was no statistically significant difference before landing in gluteus maximus(P = 0.252), biceps femoris(P = 0.613), semitendinosus(P = 0.313), and medial gastrocnemius(P = 0.140) muscles and after landing in gluteus maximus (P = 0.246), biceps femoris(P = 0.512), semitendinosus(P = 0.214), and medial gastrocnemius(P = 0.209) muscles between the two groups. Also, the TTS was higher in subjects with GV than healthy ones in the Resultant Vector TTS (P = 0.015) and medial-lateral(P = 0.013) directions.
The altered activity of the QL and GMed, in subjects with GVD may indicate instability of the spinal column, pelvis and hip during jump-landing task. Although the GVD is referred to the frontal plane deformity, the results showed that this complication might affect stability in other motion planes.
膝内翻畸形（GVD）会导致膝关节肌肉活动发生变化，这可能使个体在下肢受伤方面面临更高风险，尤其是在诸如落地等高风险活动中。
本研究旨在比较有和没有GVD的受试者在跳跃落地过程中下肢稳定肌的活动情况以及达到稳定的时间（TTS）。
共有44名男性参与本研究（第1组，有GVD，n = 22；第2组，无GVD，n = 22）；平均年龄为17.6 ± 3.12岁，身高为178.2 ± 5.39厘米，体重为80.39 ± 8.3千克。受试者被要求进行跳跃落地任务，并记录腰方肌（QL）、臀大肌（GMax）、臀中肌（GMed）、股二头肌（BF）、半腱肌和腓肠肌内侧头（MG）的肌肉活动。此外，地面反作用力（GRF）的变化量被用作TTS的一个指标。
我们的结果显示，有GVD的受试者在落地前（P = 0.008）和落地后（P = 0.017）QL活动增加。但是，与健康受试者相比，这些受试者在落地前（P = 0.033）和落地后（P = 0.005）GMed的活动减少。但两组在臀大肌（P = 0.252）、股二头肌（P = 0.613）、半腱肌（P = 0.313）和腓肠肌内侧头（P = 0.140）落地前以及臀大肌（P = 0.246）、股二头肌（P = 0.512）、半腱肌（P = 0.214）和腓肠肌内侧头（P = 0.209）落地后的活动上没有统计学上的显著差异。此外，在合力矢量TTS（P = 0.015）和内外侧（P = 0.013）方向上，有GVD的受试者的TTS高于健康受试者。
有GVD的受试者中QL和GMed活动的改变可能表明在跳跃落地任务期间脊柱、骨盆和髋关节的不稳定。尽管GVD被认为是额面畸形，但结果表明这种并发症可能会影响其他运动平面的稳定性。
