Early Superimposed NMES Training is Effective to Improve Strength and Function Following ACL Reconstruction with Hamstring Graft regardless of Tendon Regeneration

Abstract

The study aimed at investigating the effects of neuromuscular electrical stimulation superimposed on functional exercises (NMES+) early after anterior cruciate ligament reconstruction (ACLr) with hamstring graft, on muscle strength, knee function, and morphology of thigh muscles and harvested tendons. Thirty-four participants were randomly allocated to either NMES+ group, who received standard rehabilitation with additional NMES of knee flexor and extensor muscles, superimposed on functional movements, or to a control group, who received no additional training (NAT) to traditional rehabilitation. Participants were assessed 15 (T1), 30 (T2), 60 (T3), 90 (T4) and at a mean of 380 days (T5) after ACLr. Knee strength of flexors and extensors was measured at T3, T4 and T5. Lower limb loading asymmetry was measured during a sit-to-stand-to-sit movement at T1, T2, T3, T4 and T5, and a countermovement-jump at T4 and T5. An MRI was performed at T5 to assess morphology of thigh muscles and regeneration of the harvested tendons. NMES+ showed higher muscle strength for the hamstrings (T4, T5) and the quadriceps (T3, T4, T5), higher loading symmetry during stand-to-sit (T2, T3, T4, T5), sit-to-stand (T3, T4) and countermovement-jump (T5) than NAT. No differences were found between-groups for morphology of muscles and tendons, nor in regeneration of harvested tendons. NMES+ early after ACLr with hamstring graft improves muscle strength and knee function in the short- and long-term after surgery, regardless of tendon regeneration.

Superimposing neuromuscular electrical stimulation onto voluntary contractions to improve muscle strength and mass: A systematic review

“…NMES+ were administered either selectively for a specific muscle district/s (Amiridis et al, 2005; Bezerra et al, 2009, 2011; Celik et al, 2020; Feil et al, 2011; Herrero et al, 2010a, 2010b; Hwang et al, 2020; Labanca et al, 2018, 2022; Mathes et al, 2017; Paillard et al, 2005a; Pantović et al, 2015; Takano et al, 2010; Wirtz et al, 2016) or in a whole‐body configuration (Dörmann et al, 2019; D'Ottavio et al, 2019; Filipovic et al, 2019b; Ludwig et al, 2020; Micke et al, 2018; Pano‐Rodriguez et al, 2020; Teschler et al, 2021). Superimposed NMES targeted the following muscles: back extensors (Park et al, 2016); abdominals (Hwang et al, 2020); quadriceps femoris (Benavent‐Caballer et al, 2014; Bezerra et al, 2009, 2011; Celik et al, 2020; Feil et al, 2011; Herrero et al, 2010a, 2010b; Labanca et al, 2018, 2022; Mathes et al, 2017; Paillard et al, 2005a; Pantović et al, 2015; Takano et al, 2010), hamstrings (Bezerra et al, 2011; Labanca et al, 2022; Mathes et al, 2017; Wirtz et al, 2016), leg adductors (Wirtz et al, 2016); tibialis anterior (Amiridis et al, 2005; Wirtz et al, 2016), Triceps Surae (Mathes et al, 2017; Wirtz et al, 2016). The studies which applied whole‐body NMES+ adopted a similar electrodes configuration involving pectoral muscles, abdominal muscles, upper and lower back muscles, buttocks, anterior and posterior thigh muscles and lower leg muscles (Dörmann et al, 2019; D'Ottavio et al, 2019; Filipovic et al, 2019b...…”

“…Several studies reported increased muscle strength after a period of training that was based on NMES superimposed on the concentric and eccentric phase of functional dynamic exercises, which were performed in a closed kinetic chain fashion (Dörmann et al, 2019;Filipovic et al, 2019b;Labanca et al, 2018Labanca et al, , 2022Ludwig et al, 2020;Micke et al, 2018;Pantović et al, 2015). Specifically, Labanca et al showed that a rehabilitation treatment for ACL reconstructed patients, based on NMES+ superimposed on a sit-to-stand-to-sit exercise and delivered at the maximal tolerated current intensity, carried significant improvements in muscle strength of knee extensors and flexors and limb symmetry index compared to the same treatment but without electrical stimulation (Labanca et al, 2018).…”

“…Stimulation electrodes position varied across studies. In fifteen studies, electrodes were positioned on the belly of the targeted muscles (Amiridis et al, 2005;Benavent-Caballer et al, 2014;Bezerra et al, 2009;Dörmann et al, 2019;D'Ottavio et al, 2019;Filipovic et al, 2019b;Hwang et al, 2020;Ludwig et al, 2020;Mathes et al, 2017;Micke et al, 2018;Pano-Rodriguez et al, 2020;Park et al, 2016;Teschler et al, 2021;Wirtz et al, 2016) while in nine studies electrodes were placed on the motor points of the stimulated muscles (Celik et al, 2020;Herrero et al, 2010aHerrero et al, , 2010bLabanca et al, 2018Labanca et al, , 2022Paillard, 2012;Paillard et al, 2005a;Pantović et al, 2015;Takano et al, 2010) A rectangular biphasic NMES pulse waveform was used in fifteen studies (Amiridis et al, 2005;Bezerra et al, 2009Bezerra et al, , 2011Dörmann et al, 2019;Filipovic et al, 2019b;Labanca et al, 2022;Ludwig et al, 2020;Mathes et al, 2017;Micke et al, 2018;Paillard et al, 2005a;Pano-Rodriguez et al, 2020;Pantović et al, 2015;Takano et al, 2010;Teschler et al, 2021;…”

Vertical Jump Testing after Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-analysis

“…Bilateral CMJ. Seven meta-analyses of 16 studies (37,38,(41)(42)(43)45,46,(52)(53)(54)(55)57,58,61,64,72) metrics. Reconstructed limbs showed lower jump heights (SMD = −0.86, 95% CI = −0.97, −0.75), RSI (SMD = −0.85, 95% CI = −1.05, −0.65), and longer contact times (SMD = 0.26, 95% CI = 0.08 to 0.43) than uninjured contralateral limbs.…”

Does adding neuromuscular electrical stimulation to rehabilitation following total knee arthroplasty lead to a better quadriceps muscle strength recovery? A systematic review

“…In fact, with NMES, it is possible to overcome patients’ inability to voluntarily activate muscles by means of externally elicited muscle contractions, which can be increased by increasing the intensity of stimulation [6]. Therefore, to maximize the effects on the neuromuscular system, NMES can be superimposed to isometric contractions [7] or easy functional movements that can be performed also by orthopaedic patients early after surgery [8,9]. Finally, the development of battery-powered electrical stimulators allows NMES-based rehabilitation to be carried out anywhere: in rehabilitation centres as well as at patients’ homes.…”