Ikuta Futoshi, Matsuzaki Masashi, Kajitani Kotaro
School of Health Sciences, Tokyo International University, Kawagoe, Saitama, Japan.
Sonic Japan Holdings Co., Ltd, Hachioji, Tokyo, Japan.
Medicine (Baltimore). 2025 Jan 17;104(3):e41286. doi: 10.1097/MD.0000000000041286.
Chronic knee pain is a common health issue that requires effective and noninvasive treatment. We devised a novel noninvasive approach using ultrasound-guided electrical nerve reactivation (ENR) in which ultrasound is used to identify the genicular nerve (GN). Then, transcutaneous low-frequency stimulation is applied for 10 seconds. The aim of this study was to clarify the pain-relieving effects of ENR on the GN innervating the knee joint.
Patients had visited our hospital with the complaint of knee joint pain.
This study included 21 osteoarthritic knees from 16 patients with a mean age of 78.3 ± 8.5 years.
Baseline measurements included the range of motion of the knee joint, Visual Analogue Scale (VAS) scores for pain, and maximum knee flexion angle during squatting. A therapist conducted an interview to locate the painful area of the knee and then performed ultrasound-guided ENR by targeting the GN.
The preintervention VAS score was 49.3 (95% confidence interval: 41.0, 57.5). Postintervention VAS scores showed significant reductions: 27.0 (19.0, 35.1) immediately after the intervention (P < .0001), 27.7 (22.6, 32.8) at 1-day postintervention (P = .002), and 29.0 (22.9, 35.1) at 1-week postintervention (P = .001). The knee flexion angle during squatting significantly improved from 108.1° (101.6, 114.5) preintervention to 121.9° (115.1, 128.7) postintervention (P < .001). There was a significant increase in flexion angle preintervention and postintervention (P = .02); however, no significant change was observed in the extension angle. In addition, no adverse events were reported.
This study is the first to demonstrate the effects of ultrasound-guided low-frequency stimulation of the GN for knee osteoarthritis. Although the exact mechanism of pain relief is unclear, we hypothesize that alterations in neurotransmission, with or without endorphin release, may play a role. Moreover, ENR may improve nerve entrapment by causing contraction of surrounding muscles.This study demonstrated that ultrasound-guided ENR targets the GN and effectively reduces pain without complications. This treatment addresses the limitations of invasive methods, such as hydrorelease and radiofrequency ablation. Furthermore, ultrasound-guided ENR has diverse applications in diagnostics, physical therapy, and pre-exercise pain management and will greatly benefit patients and healthcare professionals.
慢性膝关节疼痛是一个常见的健康问题，需要有效且无创的治疗方法。我们设计了一种新颖的无创方法，即超声引导下的电神经再激活（ENR），其中超声用于识别膝神经（GN）。然后，进行经皮低频刺激10秒。本研究的目的是阐明ENR对支配膝关节的GN的止痛效果。
患者因膝关节疼痛前来我院就诊。
本研究纳入了16例患者的21个骨关节炎膝关节，平均年龄为78.3±8.5岁。
基线测量包括膝关节活动范围、疼痛视觉模拟评分（VAS）以及下蹲时的最大膝关节屈曲角度。治疗师进行访谈以确定膝关节的疼痛区域，然后通过靶向GN进行超声引导下的ENR。
干预前VAS评分为49.3（95%置信区间：41.0，57.5）。干预后VAS评分显著降低：干预后立即为27.0（19.0，35.1）（P<.0001），干预后1天为27.7（22.6，32.8）（P=.002），干预后1周为29.0（22.9，35.1）（P=.001）。下蹲时的膝关节屈曲角度从干预前的108.1°（101.6，114.5）显著改善至干预后的121.9°（115.1，128.7）（P<.001）。干预前后屈曲角度有显著增加（P=.02）；然而，伸展角度未观察到显著变化。此外，未报告不良事件。
本研究首次证明了超声引导下对GN进行低频刺激治疗膝骨关节炎的效果。尽管确切的止痛机制尚不清楚，但我们推测神经传递的改变，无论是否伴有内啡肽释放，可能起作用。此外，ENR可能通过引起周围肌肉收缩来改善神经卡压。本研究表明，超声引导下的ENR靶向GN，能有效减轻疼痛且无并发症。这种治疗方法解决了诸如水分离和射频消融等侵入性方法的局限性。此外，超声引导下的ENR在诊断、物理治疗和运动前疼痛管理中有多种应用，将极大地造福患者和医护人员。
