Functional rehabilitation strategies for enhancing neuromuscular control after ACL reconstruction: A systematic review.
Functional rehabilitation strategies may show promise in improving neuromuscular outcomes after ACL reconstruction, but results should be interpreted with caution due to variability in evidence quality.
Where it sits
this study against the rest of the slu-pp-332 (exercise mimetic) corpusSummary and findings
This systematic review synthesized RCT evidence on functional rehabilitation interventions targeting neuromuscular control after ACL reconstruction (ACLR). Nine RCTs involving 263 participants were included, focusing on various rehabilitation strategies and their effects on EMG-derived outcomes. Key findings included a 50% reduction in quadriceps-hamstring co-contraction and a 54±58% increase in RMS EMG amplitude following specific interventions.
Abstract
<h4>Background</h4>Arthrogenic muscle inhibition (AMI) and altered neuromuscular control commonly arise after anterior cruciate ligament (ACL) injury and may persist both preoperatively and after anterior cruciate ligament reconstruction (ACLR), potentially impairing functional recovery.<h4>Objective</h4>To synthesise randomised controlled trial (RCT) evidence on functional rehabilitation interventions targeting neuromuscular control after ACLR, using electromyography (EMG)-derived outcomes.<h4>Methods</h4>PubMed, Cochrane Library, Embase, CINAHL, Web of Science, and SPORTDiscus were searched from January 1, 2015, to December 4, 2025; duplicates were removed ( n=63 ). RCTs involving individuals undergoing ACLR (pre-operative) and/or following ACLR (post-operative) were included if they reported EMG-derived neuromuscular outcomes following functional rehabilitation. Due to heterogeneity in interventions, EMG normalisation, and outcome definitions, a structured narrative synthesis was performed.<h4>Results</h4>Nine RCTs (total n=263 ) were included. One trial examined preoperative blood flow restriction training (BFRT) preconditioning (5 sessions over 8 days before surgery), whereas the remaining interventions were delivered postoperatively. Jump training reduced quadriceps-hamstring co-contraction by 50% ( p<0.001 ). Preoperative BFRT preserved quadriceps endurance at 4 weeks post-ACLR compared with sham (sham reduction: 97±85 s) and increased root mean square (RMS) EMG amplitude by 54±58% at week 4. Aquatic proprioceptive training improved muscle activation similarity and magnitude ( p<0.01 ). Sand-based training and cross-education interventions increased EMG activity during gait phases ( p<0.05 ). Vibration therapy and postoperative BFRT produced mixed or non-significant effects. Evidence for several intervention types was limited to single trials and should be interpreted cautiously.<h4>Conclusion</h4>Functional rehabilitation strategies show limited but promising potential to improve neuromuscular outcomes following ACLR. Phase-specific approaches may be appropriate: early-phase interventions (e.g., BFRT preconditioning, vibration therapy, and cross-education) may help mitigate AMI and preserve neuromuscular capacity, whereas later-phase strategies (e.g., plyometrics and aquatic proprioceptive training) may support movement quality and motor control. Future RCTs should prioritise standardised EMG methodology and clinically meaningful endpoints (e.g., return-to-sport and reinjury).
Background
This paper addresses the issue of arthrogenic muscle inhibition (AMI) and altered neuromuscular control following ACL injury and reconstruction, which can hinder functional recovery. Previous research has identified the importance of neuromuscular control in rehabilitation, but there remains a lack of consensus on effective rehabilitation strategies. This study is significant as it aims to synthesize RCT evidence regarding functional rehabilitation interventions that specifically target neuromuscular outcomes post-ACLR.
Methods
The study involved a systematic review of RCTs identified through searches in multiple databases including PubMed and Cochrane Library, covering the period from January 1, 2015, to December 4, 2025. A total of 63 duplicates were removed, and RCTs were included if they involved individuals undergoing ACLR and reported EMG-derived neuromuscular outcomes. The review included nine RCTs with a total sample size of 263 participants, focusing on various rehabilitation interventions delivered pre- and post-operatively.
Results
The primary endpoint observed was that jump training reduced quadriceps-hamstring co-contraction by 50% (p<0.001). Other findings included that preoperative BFRT preserved quadriceps endurance at 4 weeks post-ACLR compared to sham (sham reduction: 97±85 s) and increased RMS EMG amplitude by 54±58% at week 4. Aquatic proprioceptive training showed improvements in muscle activation similarity and magnitude (p<0.01). Sand-based training and cross-education interventions increased EMG activity during gait phases (p<0.05).
Interpretation
The findings suggest that certain rehabilitation strategies may have a statistically significant impact on neuromuscular control after ACLR, but the clinical significance of these effects remains uncertain. The effect sizes reported, while statistically significant, may not translate into meaningful improvements in functional recovery for all patients. Limitations such as small sample sizes for some interventions and the variability in methodologies across studies could confound the conclusions drawn from this review.
Key findings
- Jump training reduced quadriceps-hamstring co-contraction by 50% (p<0.001).
- Preoperative BFRT preserved quadriceps endurance at 4 weeks post-ACLR compared with sham (sham reduction: 97±85 s).
- Preoperative BFRT increased root mean square (RMS) EMG amplitude by 54±58% at week 4.
- Aquatic proprioceptive training improved muscle activation similarity and magnitude (p<0.01).
- Sand-based training and cross-education interventions increased EMG activity during gait phases (p<0.05).
Limitations
- Evidence for several intervention types was limited to single trials.
- Heterogeneity in interventions and outcome definitions complicates interpretation.
- Small sample sizes in some studies may affect reliability.
- Short follow-up periods limit assessment of long-term effects.