Neuromuscular Electric Stimulation Improves Early Isometric Knee Strength After Anterior Cruciate Ligament Reconstruction and Repair: A Meta‐analysis of Randomised Controlled Trials
Arthroscopy The Journal of Arthroscopic and Related Surgery · 14 Oct 2026
† Impact is the editorial-priority score. All scores are out of 100. Clinical is a stored clinical-importance score from the earlier method; it has not been recalculated.
Why it matters
Quadriceps weakness is a major barrier to recovery and return to sport after ACL reconstruction, and NMES is a cheap, low-risk adjunct that clinicians are often unsure whether to prescribe.
The evidence
This meta-analysis pooled 21 randomised trials (687 adults) comparing standard physical therapy with versus without added neuromuscular electrical stimulation (NMES) of the thigh muscles after ACL surgery. NMES improved isometric quadriceps strength in the first 12 weeks: the mean difference was 0.23 N·m/kg (95% CI 0.16 to 0.29) in 5 studies, and there was a moderate-to-large standardised gain in limb-symmetry strength. No significant benefit appeared after 12 weeks, and isokinetic strength and IKDC scores did not differ.
Isometric knee extension strength (absolute, over body weight), ≤12 weeks postoperatively: Mean difference 0.23 (95% CI 0.16 to 0.29; other). The interval favours the first group; the size of the benefit needs clinical interpretation.
Why this rigour score?
Meta-analysis of RCTsDesign starting point: 60.8
Raised the score
- Pools randomised trials+5.1
- Compared against current standard of care+3.4
Lowered the score
- No assessment of publication bias across 13 studies−6.8
Score capped at 42. Two or more critical methodological failures for a review.
Methods at a glance
Recorded assessment- Comprehensive literature searchMet
- Risk of bias assessedMet
- Bias considered in synthesisNot met
- Publication bias assessedNot met
- Study exclusions justifiedNot met
- Prospective registrationNot reported
Not reported does not mean not done. Checks have different weights; this is not a count of boxes ticked.
See the full score breakdown
- Study design starting point
- 60.8
- Compared against current standard of care
- +3.4
- Pools randomised trials
- +5.1
- Comprehensive literature search
- +3.4
- Risk of bias assessed in the included studies
- +3.4
- No assessment of publication bias across 13 studies
- −6.8
- Journal prior (not an observed method)
- +0.6
- Methodological cap
- −27.9
- Final rigour score rounded
- 42 / 100
Study design sets the starting point and a ceiling of 96. Recorded methods then adjust the score. Points are shown to one decimal place; the final score uses unrounded values.
Checklist from the stored appraisal. “Not met” describes the recorded criterion; it does not always produce a deduction. This overview supports reading the full study.
For journal club
1.Given that the strength benefit of NMES was seen only in the first 12 weeks, which ACL reconstruction patients (for example, those with marked early quadriceps inhibition) would you prioritise for an early NMES prescription?
2.How would you counsel a patient asking whether home NMES will speed their return to sport, when early isometric strength gains did not translate into clear improvements in IKDC scores or later strength?
Original publication title
Neuromuscular Electric Stimulation Improves Early Isometric Knee Strength After Anterior Cruciate Ligament Reconstruction and Repair: A Meta‐analysis of Randomized Controlled Trials