The ultimate goal of anterior cruciate ligament reconstructions (ACLR) is to fulfil the return-to-play (RTP) criteria. Quadriceps muscle strength is one of the key determinants for a patient’s successful return-to-play after ACLR. Quadriceps muscle atrophy can persist beyond the completion of the rehabilitation program in almost half the patients and the reason behind this is still unknown. There are emerging evidences showing that pulsed electromagnetic field (PEMF) can modulate mitochondrial activities for muscle gain. PEMF exposure on top of regular exercise training may promote muscle regeneration and tissue healing. This is a double-blinded, randomized controlled trial to investigate the effects of PEMF treatment during the postoperative period on quadriceps muscle strength in ACL injured patient. Adult patients (aged 18–30) with a unilateral ACL injury, total quadriceps muscle volume is equal or more than 7% deficit on involved leg compared with uninvolved leg, sporting injury with a Tegner score of 7+, and both knees without a history of injury/prior surgery will be recruited. To estimate the improvement of patients, isokinetic muscle assessment, ultrasound imaging and MRI for quadriceps muscle thickness, self-reported outcomes with questionnaires, KT-1000 for knee laxity and biomechanical analysis, and Xtreme CT for bone mineral density will be performed. To investigate the mechanism of PEMF therapy on increasing quadriceps strength, samples of blood serum will be drawn before and after intervention. This is the first trial evaluating the effects of PEMF on quadriceps muscle recovery after ACLR. The proposed study addresses a huge research gap by evaluating practical use of PEMF as part of rehabilitation. The proposed study will provide much needed scientific support in the use of this noninvasive treatment modality to facilitate recovery of quadriceps strength after PEMF. ClinicalTrials.gov NCT05184023. Registered on 5 January 2022

中文翻译：

---

脉冲电磁场​​干预对前交叉韧带重建术后股四头肌无力患者的影响：一项双盲、随机对照试验

前交叉韧带重建 (ACLR) 的最终目标是满足回归 (RTP) 标准。股四头肌力量是患者在 ACLR 后成功重返赛场的关键决定因素之一。几乎一半的患者在完成康复计划后，股四头肌萎缩会持续存在，其背后的原因仍然未知。有新的证据表明脉冲电磁场​​ (PEMF) 可以调节线粒体活动以获得肌​​肉增益。在常规运动训练之上暴露于脉冲电磁场​​可以促进肌肉再生和组织愈合。这是一项双盲、随机对照试验，旨在调查术后期间 PEMF 治疗对 ACL 损伤患者股四头肌肌力的影响。成年患者（18-30 岁）单侧 ACL 损伤，与健侧相比，受累腿的股四头肌总肌肉量等于或超过 7%，Tegner 评分为 7+ 的运动损伤，双膝无病史将招募受伤/手术前的人。为了评估患者的改善情况，将进行等速肌肉评估、超声成像和四头肌厚度的 MRI、问卷调查的自我报告结果、用于膝关节松弛和生物力学分析的 KT-1000，以及用于骨矿物质密度的 Xtreme CT。为了研究脉冲电磁场​​治疗增加股四头肌力量的机制，将在干预前后抽取血清样本。这是第一个评估 PEMF 对 ACLR 后股四头肌恢复影响的试验。拟议的研究通过评估作为康复一部分的 PEMF 的实际使用来解决巨大的研究空白。拟议的研究将为使用这种无创治疗方式提供急需的科学支持，以促进 PEMF 后股四头肌力量的恢复。ClinicalTrials.gov NCT05184023。2022 年 1 月 5 日注册