Tim-Yun Ong Michael, Fu Sai-Chuen, Mok Sze-Wing, Franco-Obregón Alfredo, Lok-Sze Yam Stacy, Shu-Hang Yung Patrick
Department of Orthopaedics & Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.
Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.
Asia Pac J Sports Med Arthrosc Rehabil Technol. 2022 Jul 6;29:35-42. doi: 10.1016/j.asmart.2022.05.001. eCollection 2022 Jul.
Persistent quadriceps muscle atrophy is observed in a subset of patients following anterior cruciate ligament reconstruction (ACLR) despite the completion of comprehensive rehabilitation. Critically, quadriceps muscle atrophy correlates with muscle weakness and quadriceps strength deficits. The aim of this study was to examine the effect of resistance exercise on myokine levels and muscle atrophy status in ACLR patients with persistent quadriceps muscle atrophy.
Sixteen participants between the ages of 18-39 with a Tegner score of >6 and who had undergone ACLR with hamstring graft were recruited for the study. Quadriceps muscle thicknesses were ascertained by ultrasonography and isokinetic strength assessments were made prior to commencing a single bout of resistance exercise training (RET). Blood samples were taken before and after RET and assayed for myokine expression. Self-reported activity level and knee function questionnaires were completed and recorded.
Clustering by quadriceps muscle size measurements created a non-atrophy group of 9 subjects and an atrophy group of 7 subjects. There were no significant between-group differences in anthropometric measurements, time post operation and knee function questionnaires, but the atrophic group comprised of patients with lower pre-injury sporting levels. The atrophy group exhibited significant lower side-to-side muscle thickness ratios and a decreasing trend in quadriceps strength deficits. Serum brain-derived neurotrophic factor (BDNF) was up-regulated in response to RET in non-atrophy group, but a negative fold change was detected in the atrophy group.
The dysregulation in myokines plays an important role in patients failing to regain muscle mass after ACLR leading to persistent quadriceps muscle atrophy, which may potentiate greater strength deficits and poor functional recovery.
尽管完成了全面的康复训练，但在前交叉韧带重建（ACLR）后的部分患者中仍观察到股四头肌持续萎缩。至关重要的是，股四头肌萎缩与肌肉无力和股四头肌力量不足相关。本研究的目的是探讨抗阻运动对ACLR后股四头肌持续萎缩患者的肌动蛋白水平和肌肉萎缩状态的影响。
招募了16名年龄在18 - 39岁之间、Tegner评分>6且接受了腘绳肌移植ACLR手术的参与者进行研究。在开始单次抗阻运动训练（RET）之前，通过超声检查确定股四头肌厚度，并进行等速力量评估。在RET前后采集血样，检测肌动蛋白表达。完成并记录自我报告的活动水平和膝关节功能问卷。
根据股四头肌大小测量进行聚类，形成了一个由9名受试者组成的非萎缩组和一个由7名受试者组成的萎缩组。在人体测量、术后时间和膝关节功能问卷方面，两组之间没有显著差异，但萎缩组由受伤前运动水平较低的患者组成。萎缩组的左右肌肉厚度比显著较低，股四头肌力量不足呈下降趋势。非萎缩组血清脑源性神经营养因子（BDNF）在RET后上调，但在萎缩组中检测到负倍数变化。
肌动蛋白失调在ACLR后未能恢复肌肉质量导致股四头肌持续萎缩的患者中起重要作用，这可能会加剧更大的力量不足和功能恢复不良。
