The Effect of Local Anesthetic Volume Within the Adductor Canal on Quadriceps Function Evaluated by Electromyography: A Randomized, Observer-Masked, Placebo-Controlled Study in Volunteers.
试验速览
- 阶段
- 4 期
- 状态
- 已完成
- 发起方
- 入组人数
- 20
- 试验地点
- 1
- 主要终点
- Difference between ACB-groups, one hour post-block, in amplitude of the rectified vEMG signal from the vastus medialis, expressed as percentage of the pre-block value.
研究概览
简要总结
Our aim is to investigate which components of the quadriceps femoris muscle are affected following an ACB with different volumes (10, 20 and 30 ml) of 1% lignocaine evaluated by electromyography. Both a placebo treatment (20ml saline) and the femoral nerve block (20ml lignocaine 1%) as an active comparative will be used for model control. Further, we want to investigate the effect of volume on motor block. This will be evaluated by measuring the Maximum Voluntary Isometric Contraction (MVIC) of the quadriceps femoris muscle.
详细描述
The ACB has a well-proven analgesic effect after TKA, but we do not know which nerves that are affected by the block. Aside being a motor nerve, the nerve to the vastus medialis of the quadriceps femoris muscle, contains the second largest sensory contribution from the femoral nerve. It is probable that some of the analgesic effect of the ACB arises from blocking this nerve.
Even though the ACB is mainly a sensory nerve block, a study in healthy volunteers showed a small decline by 8% in quadriceps muscle strength(10). It is speculated that the decline in muscle strength was caused by the spread of local anesthetic to the nerve supplying the vastus medialis of the quadriceps femoris muscle. Three out of eleven of the volunteers experienced an even larger decline of 25 % in quadriceps muscle strength. It has been argued that this decline likely was caused by a proximal spread of the local anesthetic to the femoral triangle thereby resulting in an affection of the femoral nerve. In this study, a volume of 30 ml of local anesthetic was used.
We do not know the optimal volume for the ACB and we find it relevant to investigate to what extent and which parts of the quadriceps muscle gets affected when different volumes of a local anesthetic are injected into the adductor canal. Selective affection of the different components of the femoral quadriceps muscle can be assessed by non-invasive EMG recordings. Further, the quadriceps femoris muscle strength will be evaluated by measuring the MVIC following the different volumes. The EMG recordings will be voluntary (vEMG) measured during MVIC and stimulated (sEMG). sEMG is measured during transcutaneous electrical stimulation of the femoral nerve.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Treatment
- 盲法
- Double (Participant, Outcomes Assessor)
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- Male
- 接受健康志愿者
- 是
入选标准
- •Age > 18 years old
- •Subjects who gave their written informed consent to participating in the study after having fully understood the contents of the protocol and re-strictions.
- •BMI 18-30
- •Physical exercise 1-3 hours/week
排除标准
- •Subjects who cannot cooperate with the study.
- •Subjects who cannot understand or speak Danish.
- •Subjects with allergy to the medicines used in the study.
- •Subjects suffering from alcohol and/or drug abuse - based on the investi-gator's opinion.
- •Pathology or previous surgery or trauma to the lower limb.
- •Intense exercise 24 h before the tests
- •Intake of any analgesics 24 h prior to baseline measurements.
研究组 & 干预措施
ACB 10
ACB in right leg with 10ml of lidocaine 10mg/ml. Subject and assessor blinded, randomized. given on day 1, 2 or 3
干预措施: Lidocaine (Drug)
ACB 20
ACB in right leg with 20ml of lidocaine 10mg/ml. Subject and assessor blinded, randomized. given on day 1, 2 or 3
干预措施: Lidocaine (Drug)
ACB 30
ACB in right leg with 30ml of lidocaine 10mg/ml. Subject and assessor blinded, randomized. given on day 1, 2 or 3
干预措施: Lidocaine (Drug)
FNB
FNB in left leg with 20ml of lidocaine 10mg/ml on day 1. Unblinded arm, used for model control
干预措施: Lidocaine (Drug)
Placebo
ACB in left leg with 30ml of isotonic saline on day 2. Unblinded arm used for model control
干预措施: Saline (Drug)
结局指标
主要结局
Difference between ACB-groups, one hour post-block, in amplitude of the rectified vEMG signal from the vastus medialis, expressed as percentage of the pre-block value.
时间窗: one hour post-block
vEMG=voluntary electromyography
次要结局
- • Difference between ACB-groups, one hour post-block, in amplitude of the rectified sEMG signal from the vastus medialis, expressed as percentage of the pre-block value.(one hour post-block)
- • Difference between ACB-groups, one hour post-block, in amplitude of the rectified sEMG signal from the vastus lateralis, expressed as percentage of the pre-block value.(one hour post-block)
- • Association between volume and MVIC. MVIC expressed as a percentage of the pre-block value.(one hour post-block)
- Difference in proportions between ACB-groups having an affection of both the saphenous nerve and the vastus medialis (but no other components of the quadriceps femoris muscle), one hour post block evaluated by EMG(one hour post-block)
- • Difference between ACB-groups, one hour post-block, in amplitude of the rectified vEMG signal from the vastus lateralis, expressed as percentage of the pre-block value.(one hour post block)
- • Difference between groups, one hour post-block, in MVIC expressed as percentage of the pre-block value(one hour post-block)
研究者
Ulrik Grevstad
Associate professor
University Hospital, Gentofte, Copenhagen