. 2019 Dec 27;2019:3480512. doi: 10.1155/2019/3480512

Table 3.

Summary of included TMS studies (effect size is presented for between or within-group comparisons).

Study	Level of evidence	Group (n, sex, mean age)	Type of surgery; time from injury/surgery	Outcomes	Task	Results	Effect size, Cohen's d
Pietrosimone et al. [35]	Case-control 3b	ACLR (n = 28, 9M, 19F, age = 21.3 ± 3.8) Healthy (n = 29, 9M, 20F, age = 21.5 ± 2.7)	14 hamstrings, 12 patellar tendons, 2 allografts; 48.1 ± 36.2 months from surgery	AMT	Vastus medialis contraction at 5% MVIC	AMT was significantly higher in the ACLR limb (45.1 ± 15.2) compared to the uninvolved limb (38.4 ± 14.4)—P = 0.003 AMT was significantly higher in the ACLR limb (45.1 ± 15.2) compared to healthy controls (37.5 ± 12.7)—P = 0.04	ACLR vs. uninvolved limb, d = 0.46 ACLR vs. healthy, d = 0.54

Pietrosimone et al. [44]	Case series 4	ACLR (n = 15, 4 M, 11F, age = unknown)	Unknown; 54.4 ± 12.0 months from surgery	AMT	Vastus medialis contraction at 5% MVIC	The ACLR limb presented average AMT values of 33.2 ± 12.1%T	Unable to determine

Lepley et al. [54]	Case-control 3b	ACLR (n = 29, 9M, 20F, age = 21.2 ± 3.7) Healthy (n = 29, 9M, 20F, age = 21.5 ± 2.7)	Unknown; 48 ± 36 months from surgery	AMT	Vastus medialis and lateralis contraction at 5% MVIC	The ACLR group showed higher values of AMT (43.9 ± 16.3%2T) compared to healthy controls (37.5 ± 12.7%T), but the significance level of this difference is unknown	ACLR vs. healthy, d = 0.43

Lepley et al. [33]	Case-control, 3b	ACLR (n = 20, 9M, 11F, age = 20.9 ± 4.4) Healthy (n = 20, 9M, 11F, age = 21.7 ± 3.7)	Nine hamstrings, 11 patellar tendons Measurements taken at 3 points: (a) 37.1 ± 15.3 days after injury (b) 15.9 ± 2.4 days after surgery (c) 28.3 ± 2.9 weeks after surgery	AMT, MEP	Vastus medialis contraction at 5% MVIC	Both at presurgery and 2 weeks after surgery, there were no differences between groups in the AMT values At 6 months postsurgery, both the ACLR limb (46.1 ± 8.7%T) and the uninvolved limb (47.4 ± 6.5%T) showed significantly higher AMT compared to the healthy group (36.8 ± 8.6%T) No differences were found for MEP in any time point	For AMT: ACLR vs. uninvolved, d = 0.1-0.4 ACLR vs. healthy, d = 0.3-1.0

Ward et al. [53]	Case-series, 4	ACLD (n = 28, 7M, 21F, age = 22.4 ± 3.7)	Unknown; 52 ± 42 months from injury	AMT	Vastus medialis contraction at 5% MVIC	There were no significant differences between the ACLD limb (46.4 ± 9.9%T) and the uninvolved limb (43.9 ± 8.6%T)—P = 0.24	ACLD vs. uninvolved, d = 0.27

Kuenze et al. [48]	Case-control, 3b	ACLR (n = 22, 12M, 10F, age = 22.5 ± 5.0) Healthy (n = 24, 12M, 12F, age = 21.7 ± 3.6)	12 hamstrings, 10 patellar tendons; 37.3 ± 26.3 (hamstring) and 24.5 ± 15.6 (PT) months from surgery	AMT	Vastus medialis contraction at 5% MVIC	The ACLR limb showed a significantly higher AMT (61.8 ± 12.0%T) compared to the uninvolved limb (56.0 ± 14.5%T), but not when compared to the healthy group (63.1 ± 10.3%T)	ACLR vs. uninvolved, d = 0.45 ACLR vs. healthy, d = 0.17

Luc-Harkey et al. [55]	Case-series, 4	ACLR (n = 27, 7M, 20F, age = 21.8 ± 3.2)	18 patellar tendons (remaining unknown); 44.5 ± 36.6 months from surgery	AMT, ICF, SICI, MEP	Vastus medialis contraction at 5% MVIC	No significant differences in AMT were observed between the ACLR (48.2 ± 13.1%T) and the uninvolved limb (46.0 ± 12.6%T). No significant differences were observed for the remaining outcomes	For AMT: ACLR vs. uninvolved, d = 0.17

Norte et al. [51]	Case-control, 3b	ACLR (n = 72, 32M, 40F, age = 26.0 ± 9.3) Healthy (n = 30, 12 M, 18F, age = 22.7 ± 4.6)	34 hamstrings, 29 patellar tendons, 9 allografts; 46.5 ± 58.0 months from surgery	AMT	Vastus medialis contraction at 5% MVIC	AMT values between the ACLR limb (45.2 ± 8.6%T) and the uninvolved limb (44.3 ± 8.4%T) were not significant; however, significant differences were found in the healthy group (39.0 ± 4.1%T)	ACLR vs. uninvolved, d = 0.11 ACLR vs. healthy, d = 0.81

Norte et al. [50]	Case-control, 3b	ACLR_early (n = 34, 20M, 14F, age = 22.5 ± 6.3) ACLR_late (n = 30, 10M, 20F, age = 24.9 ± 5.9) ACLR_OA (n = 8, 2M, 6F, age = 45.4 ± 7.4) Healthy (n = 30, 12M, 18F, age = 22.7 ± 4.6)	29 hamstrings, 26 patellar tendons, 23 allografts; ACLR_early = 9.0 ± 4.3, ACLR_late = 70.5 ± 41.6, ACLR_OA = 115.9 ± 110.0 months from surgery	AMT	Vastus medialis contraction at 5% MVIC	No significant differences in AMT were found between the ACLR limb and the uninvolved limb, both at early (45.8 ± 7.9%T vs. 45.1 ± 7.4%T) and late (42.8 ± 9.1 vs. 42.3 ± 9.5) stages—P = 0.60 Both limbs of people with ACLR showed significant differences in AMT compared to the healthy controls (39.0 ± 3.4%T)—P < 0.05	All ACLR groups vs. uninvolved limb d = 0.05-0.09 All ACLR groups vs. healthy, d = 0.6-1.1

Zarzycki et al. [52]	Case-control, 3b	ACLR (n = 18, 8M, 10F, age = 21.8 ± 3.3) Healthy (n = 18, 8M, 10F, age = 22.2 ± 2.5)	Eight hamstrings, 5 patellar tendons, 3 allografts; 14.0 ± 3.0 days after surgery	ICF, MEP, SICI, and RMT	Participant seated in dynamometer and relaxed	No significant differences were found in RMT between the ACLR limb (61.4 ± 12.4%T) and the uninvolved limb (67.9 ± 15.4%T)—P = 0.39 The ACLR limb showed significantly higher RMT compared to healthy controls (55.6 ± 8.2%T)—P = 0.001 ACLR group showed higher MEP in both limbs compared to both healthy-matched limbs. ACLR group showed between-limb differences in SICI. No differences were observed in ICF	For RMT: ACLR vs. uninvolved, d = 0.46 ACLR vs. healthy, d = 0.54

Ward et al. [59]	Case-control, 3b	ACLR (n = 18, 12M, 6F, age = 29.6 ± 8.4) Healthy (n = 18, 12M, 6F, age = 29.2 ± 6.8)	Unspecified; 69.5 ± 42.5 days after surgery	AMT, CSP, ICF, LICI, MEP, and SICI	Rectus femoris contraction at 10% MVIC	Differences in AMT between the ACLR limb (51.8 ± 9.9%T), the uninvolved limb (50.1 ± 9.2%T), and healthy controls (53.3 ± 8.9%T) were not significant The ACLR limb showed longer CSP compared to the uninvolved limb and healthy controls. No differences were observed for MEP, LICI, and SICI	For AMT: ACLR vs. uninvolved, d = 0.17 ACLR vs. healthy, d = 0.16

Héroux and Tremblay [58]	Case-control, 3b	ACLD (n = 10, 4M, 6F, age = 27 ± 8) Healthy (n = 4, 4F, age = 23 ± 3)	22 (range 4-108) months from injury	RMT and MEP	Quadriceps contraction for MEP recordings (details unspecified)	RMT values from the ACLD limb were significantly lower (P = 0.02) compared to the uninvolved limb. No comparisons were made to the healthy group No differences were observed for MEP	Unable to determine

%T = percentage of 2.0 tesla; ACLD = anterior cruciate ligament deficiency; ACLR = anterior cruciate ligament reconstruction; AMT = active motor threshold; CSP = cortical silent period; ES = effect size; F = females; ICF = intracortical facilitation; LICI = long-interval intracortical inhibition; M = males; MEP = motor-evoked potential; MVIC = maximal voluntary isometric contraction; RMT = resting motor threshold; SICI = short-interval intracortical inhibition.