Cross-education improves quadriceps strength recovery after ACL reconstruction: a randomized controlled trial

Abstract

Purpose The aim of this study was to investigate the efects of concentric and eccentric cross-education (CE) on quadriceps strength and knee function recoveries after anterior cruciate ligament (ACL) reconstruction. Methods Forty-eight patients (age: 29.5 ± 6.8 years, body mass index: 26.1 ± 3.2 kg/m 2 ) who had undergone ACL reconstruction with hamstring tendon autograft were included in the study. The patients were randomly divided into three groups when they reached four weeks post surgery: (1) concentric CE (n = 16); (2) eccentric CE (n = 16); and (3) control (n = 16). All groups followed the same post-surgical rehabilitation program for their reconstructed limb. Additionally, the two experimental groups followed eight weeks of isokinetic training for the uninjured knee at 60°/s for 3 days per week. Quadriceps maximum voluntary isometric strength (MVIC) was measured during the 4th week (pre-training), 12th week (post training), and 24th week post surgery. The single-leg hop distance and International Knee Documentary Committee (IKDC) scores were also evaluated during the 24th week post surgery. Analysis of variance was used for statistical analysis. Results Group-by-time interaction was signiicant for quadriceps MVICs for reconstructed and healthy limbs (p = 0.02). Quadriceps strength of both knees was greater in concentric and eccentric CE groups compared to control group during the 12th-and 24th weeks post surgery (p < 0.05). Strength gain was 28% and 31% in concentric and eccentric CE groups, respectively, when compared with the control group. Concentric and eccentric CE had similar efects on quadriceps strength recovery (n.s.). IKDC score, and single-leg hop distances were not signiicantly diferent among groups (n.s.). Conclusions Concentric and eccentric quadricep strengthening of healthy limbs in early phases of ACL rehabilitation improved post-surgical quadriceps strength recovery of the reconstructed limb. CE should be integrated into ACL reconstruction rehabilitation, especially in the early rehabilitative phases to restore quadriceps strength. Level of evidence Randomized controlled trial, Level I.

Contralateral Effects of Unilateral Strength and Skill Training: Modified Delphi Consensus to Establish Key Aspects of Cross-Education

“…In round 1, > 90% of respondents agreed on the potential clinical utility of the transfer, both for strength and motor skills. Cross-education was deemed suitable to orthopedic conditions and sports injuries, which is consistent with promising data from orthopedic cohorts [41,42], even though other studies have reported no significant value in adding crosseducation to conventional rehabilitative programs [43,44]. Unexpectedly, no consensus was reached in either round (59-67%) regarding the potential use of cross-education for treating neurological patients, despite favorable findings in stroke survivors and people with multiple sclerosis [24][25][26][45][46][47][48][49].…”

Cross-education and detraining effects of eccentric vs. concentric resistance training of the elbow flexors

“…A meta-analysis study concluded that the cross-education effect was observed irrespective of age, gender, and disease status, and the magnitude of increase in muscle strength of the non-trained muscle is 70–77 % of that of the trained muscle on average [ 15 ]. The cross-education effect may be useful for dealing with unilateral disorders due to fracture [ 23 ], ligament injury [ 17 ], and hemiplegia [ 11 ]. However, this may not be always the case, since Zult et al [ 33 , 34 ] reported that quadriceps resistance training of the non-operated leg of patients with anterior cruciate ligament (ACL) reconstruction did not accelerate recovery.…”

Low-Load Unilateral and Bilateral Resistance Training to Restore Lower Limb Function in the Early Rehabilitation After Total Knee Arthroplasty: A Randomized Active-Controlled Clinical Trial

“…A recent study by Onigbinde et al analyzed the effect of a unilateral strength training of the unaffected leg in knee osteoarthrosis patients (3 times/week for 6 weeks; 3 sets of 12 isometric maximal voluntary contractions) and found an increase in quadriceps muscle strength of around 20% in both legs indicating a cross education effect ( 20 ). Similarly, Harput et al have found that concentric and eccentric cross education interventions (3 times/week for 8 weeks, 3 sets of 12 isokinetic maximal voluntary contractions) improved isometric maximal voluntary contraction strength compared to standard care after ACL reconstruction ( 47 ).…”