Table 3 Participants’ characteristics of included studies

Busch et al. (2019) [13]

N = 20; N = 10 ACLR (age: 26 ± 10 yrs; height: 175 ± 6 cm; mass: 75 ± 14 kg) and N = 10 healthy matched controls (age: 31 ± 7 yrs; height: 175 ± 7 cm; mass: 68 ± 10 kg)

N = 10 ACLR (13.2 ± 2 months since repair), quadriceps tendon graft by same surgeon, some with additional injuries which needed surgery

TAS min. 4

N = 10 ACLR participants; age 26 ± 10 yrs, height: 175 ± 7 cm, weight: 75 ± 14 kg, 3 females and 7 males, TAS 7 ± 2

n.a.

N = 10 healthy participants without prior injury of the knee, age 31 ± 7 yrs, height 175 ± 8 cm, weight 68 ± 10 kg, 3 females and 7 males, TAS 6 ± 1; matched according to age, height, weight, gender, (sports) activity level and leg dominance

No

Alkjaer et al. (2003) [33]

N = 29; N = 19, all male, complete chronic (post-injury time 6 months or more) ACLD and N = 10 healthy males as controls for EMG

Complete chronic ACLD, min. 6 months of rehab program after injury, ACL injury clinically diagnosed by experienced orthopedic surgeons with Lachman, Anterior Drawer and Pivot-Shift Tests; TLS scores applied to separate ACLD-participants in copers and non-copers

Min. 2 h/wk of physical activity

N = 9; male copers; (mass: 76.7 (14.3) kg, height: 1.81 (0.06) m, age: 28.3 (6.1) yrs); mean TLS scores: 87.1 (5.8) and 6.1 (0.6) respectively; mean time after injury: 39.1 (42.3) (range 6.0–120.0) months

N = 10; male non-copers; mass: 80.4 kg (SD 6.7); height: 1.79 m (SD 0.05), age: 31.7 yrs (SD 5.9); mean TLS scores: 74.0 (SD 7.1) and 3.8 (SD 0.6), respectively; mean time after injury: 55.0 months (SD 42.7) (range 6.0–144.0)

N = 10; male healthy; mass: 77.5 kg (SD 7.9), height: 1.82 m (SD 0.05), age: 31.0 yrs (SD 2.8)

No

Alkjaer et al. (2002) [34]

N = 23 all male; N = 17 males with complete ACLD, N = 6 healthy controls

Complete ACLD, min. 6 months of rehab program after injury; TLS scores applied to separate ACLD-participants in copers and non-copers

Min. 2 h/wk

N = 8; male copers; weight: 76.6 kg (SD 14.8); height: 1.81 m (SD 0.06), age: 26.0 yrs (SD 4.0); mean TLS scores: 85.5 (SD 5.3) and 6.25 (SD 0.5), respectively, mean time after injury: 34.0 months (SD 39.2) (range 6.0–120.0)

N = 9; male non-copers; weight: 80.6 kg (SD 7.1); height: 1.79 m (SD 0.06), age: 31.2 yrs (SD 6.0); mean TLS scores: 74.0 (SD 7.1) and 3.8 (SD 0.6), respectively; mean time after injury: 51.8 months (SD 44.0) (range 6.0–144.0)

N = 6; male healthy; weight: 73.8 kg (SD 7.9), height: 1.81 m (SD 0.05), age: 31.0 yrs (SD 1)

No

Arnason et al. (2014) [35]

N = 36; N = 18, female and male soccer players with ACLR (post-injury time 1–6 yrs) and N = 18 healthy female and male soccer players from the same team (men’s and women’s top league in Iceland), matched for gender, height, body mass and “involved” side designation, as controls

ACLR: successful return to full participation in soccer; no muscle strain injury in knee flexors in past 3 months, no orthopedic condition excluding from soccer

Full participation in soccer (Icelandic top leagues)

N = 18 ACLR participants in total; N = 8 males, N = 10 females; all participants mean mass: 69.2 (11.8) kg, height: 1.73 (0.09) m, age: 23.7 (3.6) yrs; mean BMI: 23.0 (2.4) kg/m²; left/right dominance 2/16; involved/uninvolved is the dominant leg 8/10; time since injury 1–6 yrs

n.a.

N = 18 healthy participants; N = 8 males, N = 10 females; all participants mean mass: 68.6 (11.2) kg, height: 1.73 (0.08) m, age: 20.5 (3.7) yrs; mean BMI: 22.7 (2.0) kg/m2

No

Bryant et al. (2009) [36]

N = 59; N = 10 males with ACLD (18–35 yrs); N = 27 matched males with ACLR (14 with patella tendon graft, 13 with combined ST and gracilis graft); N = 22 matched controls

Cincinnati Knee Rating System (0–100 points); ACLD: full ROM, neg. Lachman, neg. Pivot-Shift; confirmed isolated ACL rupture (arthroscopic) min. 1 yr before testing; same orthopedic surgeon for all ACLR

n.m., but hopping required

N = 10 male with ACLD (18–35 yrs)

N = 27 matched males with ACLR (14 with patella tendon graft, 13 with combined ST and gracilis graft)

N = 22 matched (age, activity level, anthropometrics), healthy controls no history of trauma or disease in either knee and no evidence of abnormality on clinical examination

No

Burland et al. (2020) [37]

N = 36; N = 16 females ACLR, N = 10 males ACLR, N = 8 healthy controls (N = 4 females, N = 4 males)

Unilateral ACLR, 21 subjects with BPTB graft, 5 with hamstrings graft; enrolled in physician-directed rehabilitation program, able to do single limb forward hop

n.m. as criteria for in-/exclusion; minimum TAS of 5 preinjury/after surgery

N = 26 with ACLR, age: 20.2 ± 2.7 yrs, mean time since injury: 2.2 ± 2.7 yrs, TAS preinjury: median 8.0 (range 5.0–10.0), after surgery 7.0 (range 5.0–9.0) points, cleared for unrestricted RTS

n.a.

N = 8 healthy controls, age: 23.3 ± 1.8 yrs, TAS: median 9.0 (range 5.0–10.0) points

No, except age

Cordeiro et al. (2015) [38]

N = 17 males; N = 8 with ACLR and N = 9 healthy controls

ACLR: min. 6 months post-surgery on dominant leg, bone-tendon-bone arthroscopy, no problems at end of physiotherapy phase

Soccer, professional level

N = 8 professional male soccer players (age:  24.6 ± 3.5 yrs, height: 1.83 ± 0.06 m, mass: 77.3 ± 7 kg) with ACLR min. 6 months since surgery

n.a.

N = 9 healthy controls; professional male soccer players (age: 24.0 ± 3.5 yrs, height: 1.76 ± 0.05 m, mass: 72.9 ± 3.5 kg), no knee or leg injuries or previous ACL surgeries

No

Dashti Rostami et al. (2019) [39]

N = 36; N = 12 ACLD, N = 12 ACLR; N = 12 healthy controls; all male athletes

For patients: primary unilateral ACL injury

Athletes, regular sports participation, ACLD = copers

N = 12 males, 18 to 36 months post-ACLR

N = 12 males, 18 to 36 months after ACL rupture (= ACLD, copers); grade 2 or 3 rupture including the following definition of copers: athletes with ACLD for at least 18 months, no symptoms of knee instability during regular sports participation

N = 12 healthy males, matched controls; no knee injury, no knee pain

No

Jordan et al. (2016) [40]

N = 22; N = 11 ACLR, N = 11 control; elite skiing athletes from Canada’s national alpine skiing and skier cross team

ACLR: primary ACL injury, at least 12 months post-surgery, actively competing athletes at the Federation International de Ski World Cup level with full medical clearance to compete

Elite ski racers, TAS 10, competing at international level

N = 11 actively competing ACLR skiers (females, n = 5: age: 23.6 ± 1.8 yrs, mass: 61.0 ± 5.3 kg; males, n = 6: age: 26.5 ± 5.8 yrs, mass: 84.4 ± 9.0 kg; 7 subjects with ST autograft, 1 with BPTB autograft, 3 with cadaver allograft

n.a.

N = 11 matched controls with no history of ACL injury (females, n = 5: age: 21.8 ± 3.2 yrs, mass: 63.7 ± 4.6 kg; males, n = 6: age: 23.3 ± 3.3 yr, mass: 84.7 ± 5.1 kg; active competitors at the international level defined as participation in the Federation International de Ski World Cup circuit

n.m.

Lessi et al. (2017) [41]

N = 40; N = 20 with ACLR, N = 20 healthy controls

ACLR: non-contact ACL injury, unilateral reconstruction of the ACL with no prior history of a contralateral ACL injury, no recent history of an ankle, hip, spine, or contralateral knee injury in the past 12 months; rehabilitation completed, cleared to RTS by both their physician and physical therapist

Recreational sports, meaning aerobic or athletic activity at least 3x/wk

N = 20 with ACLR, 13 males, 7 females, at least 12 months post-surgery, 13 with hamstring ipsilateral autografts, 7 with BPTB ipsilateral autograft

n.a.

N = 20 healthy controls, 13 males, 7 females, no history of any dysfunction or previous joint trauma, no prior history of ACL injury or injury of lower extremity in last 12 months; were matched by age, sex, weight, and current sporting activity type

No

Oliver et al. (2018) [42]

N = 25 ACLD, mean age: 22 ± 4.61 yrs, mean mass: 71.18 ± 10.57 kg, mean height: 177.55 ± 9.69 cm; N = 18 males (72%); N = 2 lost to follow-up due to personal issues, all remaining 23 patients concluded the study (pre-surgery, 4 and 6 months post-surgery for questionnaires, at 6 months for jumps)

Complete ACL tear was based on clinical symptoms, on positive Lachman and pivot shift tests, and was confirmed by magnetic resonance imaging; reconstruction 2–3 months after the injury by same surgeon using BTB-technique

More than 200 h of sports activity per year, including jumping, pivoting and twisting actions

Injured knee

Non-injured knee

n.a.

n.a.

Ortiz et al. (2014) [43]

N = 31 females; N = 15 ACLR, N = 16 healthy females

ACLR: same orthopedic surgeon, same rehabilitation protocol, N = 13 were injured while participating in competitive volleyball at the collegiate or professional level; at least 12 months post-surgery, full RTS allowed (without restrictions) to pre-injury level

Sports-specific physical activities as described by the Activity Rating Scale, scores from 12 to 16, consistent with activities such as running, cutting, decelerating, and pivoting more than 2x/wk = high level of participation

N = 15 ACLR with SG graft, age range: 21–35 yrs (height: 167.71 ± 9.0 cm, body mass: 67.68 ± 11.66 kg), time since surgery was between 12 months and 5 yrs, full RTS allowed (pre-injury level); N = 1 drop-out due to inability to perform tasks

n.a.

N = 16 healthy females, participating in volleyball, basketball, and soccer at the collegiate or intramural sports level, age range: 21–35 yrs, height: 160.50 ± 5.17 cm, body mass: 59.35 ± 10.37 kg

No for age and activity, height and weight

Patras et al. (2009) [44]

N = 9 males with ACLR

ACLR: unilateral ACL tear confirmed by MRI and arthroscopy, BPTB graft within 6 months after injury, same rehabilitation protocol, RTS permitted 6 months post-surgery

Athletes, amateur soccer players, at least TAS 7

N = 9 males with ACLR, mean age: 27.7 ± 3.5 yrs, mean weight: 79.5 ± 7.3 kg, mean height: 178 ± 5.9 cm, mean time since surgery: 19.2 ± 5.7 months, median Lysholm score: 95 (range 94–96), TAS: 8 (range 7–9), resumed their sports activities

n.a.

n.a., non-injured side respectively

n.a.

Patras et al. (2010) [45]

N = 28 males; N = 14 ACLR, N = 14 healthy controls

ACLR: unilateral ACL tear confirmed by MRI and arthroscopy, BPTB graft, performed within 6 months after injury, same surgeon, same rehabilitation, RTS permitted after 6 months post-surgery

Amateur soccer players

N = 14 males with ACLR, mean age: 24.8 ± 5.3 yrs; mean height: 177 ± 5.3 cm, mean weight 77.3 ± 7.5 kg, time since surgery: mean 18.5 ± 4.3 months, pre-injury level of sports participation, median Lysholm score 95 (range 94–100) and TAS 8 (range 7–9)

n.a.

N = 14 healthy males, mean age: 21.7 ± 4.4 yrs; mean height: 180 ± 9.0 cm, mean weight 72.2 ± 8.3 kg, never suffered of any kind of orthopedic or neurological condition; left leg = control leg

n.m.

Pincheira et al. (2018) [46]

N = 50 male soccer players; N = 25 with unilateral ACLR, N = 25 uninjured controls

ACLR: unilateral ACLR with ST-gracilis graft, same surgical team, at least 6 months post surgery; non-contact mechanism during soccer match on the dominant limb

Amateur soccer players, playing at least 2x/wk

N = 25 males with ACLR, age: 28.36 ± 7.87 yrs; weight: 77.56 ± 6.35 kg, height: 169 ± 7 cm, time after surgery: 9 ± 3 months, time between ACL injury and surgery: 3.4 ± 1 months; at time of measurements cleared for full RTS

n.a.

N = 25 healthy males, age: 24.16 ± 2.67 yrs; weight 78.16 ± 5.46 kg, height 172 ± 5 cm; without injury or surgery on lower limb

No

Rudolph et al. (2001) [47]

One component of a larger study; N = 31; N = 10 healthy controls, N = 11 ACLD copers, N = 10 ACLD non-copers

ACLD: full range of motion in both knees, no visible or palpable knee effusion, no symptoms of locking, an uninvolved, healthy knee

Athletes, regular activity in level I sports (involving jumping, pivoting, and hard cutting) and level II sports (involving lateral motions) before injury

N = 11 ACLD copers (2 females, 9 males), age range: 22–43 yrs, mean 30.7 yrs, high-level athletes with ACLD for at least 1 year (confirmed by MRI), any knee instability during regular participation in level I and II sports, no more than one episode of giving way, even during sports, since injury

N = 10 non-copers ACLD (4 females, 6 males), age range: 16–43 yrs, mean 28.1 yrs; more than one episode of giving way since injury, instability during ADL, not returned to sports

N = 10 uninjured individuals, matched by age and activity level to the coper subjects (2 females, 8 men), age range: 23–41 yrs, mean 32.2 yrs)

No (age and joint laxity)

Rudolph et al. (2000) [48]

One component of a larger study; N = 31; N = 10 healthy controls, N = 11 ACLD copers, N = 10 ACLD non-copers

ACLD: full range of motion in both knees, no visible or palpable knee effusion, no symptoms of locking, an uninvolved, healthy knee

athletes, regular activity in level I sports (involving jumping, pivoting, and hard cutting) and level II sports (involving lateral motions) before injury

N = 11 ACLD copers (2 females, 9 males), age range: 22–43 yrs, mean 30.7 yrs, high-level athletes with ACLD for at least 1 year (confirmed by MRI, any knee instability during regular participation in level I and II sports, no more than one episode of giving way, even during sports, since injury

N = 10 non-copers ACLD (4 females, 6 males), age range: 16–43 yrs, mean 28.1; more than one episode of giving way since injury, instability during ADL, not returned to sports

N = 10 uninjured individuals, matched by age and activity level to the coper subjects (2 females, 8 men), age range: 23–41 yrs, mean 32.2 yrs)

n.m.

Rudolph and Snyder-Mackler (2004) [49]

One component of a larger study; N = 31; N = 10 healthy controls, N = 11 ACLD copers, N = 10 ACLD non-copers

ACLD: full range of motion in both knees, no visible or palpable knee effusion, no symptoms of locking, an uninvolved, healthy knee

Athletes, regular activity in level I sports (involving jumping, pivoting, and hard cutting) and level II sports (involving lateral motions) before injury

N = 11 ACLD copers (2 females, 9 males), age range: 22–43 yrs, mean 30.7 yrs, high-level athletes with ACLD for at least 1 year (confirmed by MRI, any knee instability during regular participation in level I and II sports, no more than one episode of giving way, even during sports, since injury

N = 10 non-copers ACLD (4 females, 6 males), age range: 16–43 yrs, mean 28.1 yrs; more than one episode of giving way since injury, instability during ADL, not returned to sports

N = 10 uninjured individuals, matched by sex, age and activity level to the coper subjects (2 females, 8 men), age range: 23–41 yrs, mean 32.2 yrs)

No (age and leg length)

Swanik et al. (2004) [50]

N = 29; N = 12 female ACLD, N = 17 female controls

Complete unilateral ACL tear, at least 1 year after injury, mechanical instability (positive Lachman and Pivot-Shift tests), rehabilitation program completed, no ACL surgery

Minimum TAS of 3

N = 12 females with ACLD, age: 25.2 ± 7.3 yrs, mean time since injury 33.6 ± 5.2 months, TAS 5.4 ± 1.83 points

n.a.

N = 17 healthy females, age: 22.7 ± 4.0 yrs, TAS 5.41 ± 1.5 points

n.m.

Briem et al. (2016) [51]

N = 36; N = 18, female players with ACLR (post-injury time 1–6 yrs) and N = 18 healthy female players from the same team (from Icelandic women’s top league in handball, football, basketball), matched for gender, height, body mass and “involved” side designation, as controls

No information about diagnosis or treatment; exclusion criteria: current musculoskeletal injury, lower limb muscle strain within 3 previous months, not being able to do single-limb hops

ACLR: successful return to competition with their teams; healthy: full participation in soccer (Icelandic top leagues)

N = 18 females, ACLR, recruited via advertisement from teams competing in the top leagues in three team sports handball (n = 5), basketball (n = 4), and football (n = 9)]. In 12 instances, the surgical limb was the individual’s dominant one. Characteristics: mean mass: 67.2 (7.8) kg, height: 1.714 (0.05) m, age: 22.7 (3.5) yrs; mean BMI 22.8 (2.4) kg/m2; involved/uninvolved is the dominant leg 12/18; time since injury 1–6 yrs

n.a.

N = 18 healthy females recruited from the same teams, matched for age, height, weight. Characteristics mean mass: 66.3 (7.1) kg, height: 1.708 (0.05) m, age: 21.5 (2.7) yrs; mean BMI 22.7 (2.2) kg/m2

No

Lessi et al. (2018) [52]

N = 14 ACLR (7 males, 7 females) from study of Lessi et al. (2017) [41]

Non-contact ACL injury; unilateral ACLR with autologous ipsilateral graft at least 12 months before recruitment; undergone a rehabilitation program; returned to sports participation; no contralateral ACL injury

Recreational sports

N = 7 males ACLR, age: 23.90 ± 2.80 yrs, height: 1.80 ± 0.1 m, mass: 83.3 ± 7.8 kg, 3 with BPTB graft, 4 with flexor tendons grafts

N = 7 females ACLR, age: 24.7 ± 5.3 yrs, height: 1.63 ± 0.1 m, mass: 65.9 ± 9.0 kg, 2 with BPTB graft, 5 with flexor tendons grafts

n.a.

No, except men were taller than women (P < 0.001) and performed a higher number of sets of the protocol before becoming fatigued their reconstructed limb (P = 0.006)

Lustosa et al. (2011) [53]

N = 25 ACLR; N = 15 with Cincinnati Knee Rating System (CKRS) > 90 points (full RTS), N = 10 with CKRS < 85 points (limited RTS)

At least 2 yrs post-surgery, same rehabilitation program which allowed full RTS activities 7 months post-surgery

Full RTS allowed, not further specified

N = 10 ACLR with CKRS 77.30 ± 6.14 points, age: 33.4 ± 7.53 yrs, time between injury and surgery 52.20 ± 31.33 months, 3 with associated meniscal injuries, 7 without

N = 15 ACLR with CKRS 96.87 ± 2.75 points, age: 34.5 ± 8.85 yrs, time between injury and surgery 67.3 ± 28.5 months, 3 with associated meniscal injuries, 12 without

n.a.

No

Nyland et al. (2010) [54]

N = 70 ACLR; N = 35 males; N = 35 females, 5.3 ± 3 yrs post-surgery

Minimum of 2 yrs since unilateral primary ACL reconstruction with allografts performed by same surgeon, standard rehabilitation program with sufficient adherence

Met or exceeded standard accepted RTS activity goals of a minimum 85% bilateral equivalence with single-leg hop–for–distance testing and 60°/s isokinetic peak knee extensor and flexor torque testing

N = 35 males with ACLR, age n.m., height: 180.3 ± 6.9 cm, weight: 88.9 ± 13.3 kg, time after surgery 5.6 ± 3.2 yrs

N = 35 females with ACLR, age n.m., height: 166.6 ± 7.1 cm, weight: 68.2 ± 18.9 kg, time after surgery 5.1 ± 2.6 yrs

n.a.

n.m.

Nyland et al. (2013) [55]

N = 70 ACLR; 35 male and 35 females, 5.3 ± 3 yrs after surgery; secondary analysis of Nyland et al., 2010 [54]

Minimum of 2 yrs since unilateral primary ACL reconstruction with allografts performed by same surgeon, standard rehabilitation program with sufficient adherence

Met or exceeded standard accepted RTS activity goals of a minimum 85% bilateral equivalence with single-leg hop–for–distance testing and 60°/s isokinetic peak knee extensor and flexor torque testing

N = 24 ACLR well-trained/frequently sporting, 50% males, age at surgery 29.8 ± 11.4 yrs, height: 172.5 ± 8.6 cm, weight: 77.1 ± 18.2 kg, time post-surgery 5.7 ± 2.8 yrs, IKDC 87.3 ± 11.5

N = 26 ACLR only sporting sometimes, 50% males, age at surgery 33.1 ± 13.5 yrs, height: 171.7 ± 9.7 cm, weight: 79.4 ± 23.2 kg, time post-surgery 5.4 ± 3.1 yrs, IKDC 87.3 ± 11.5

No healthy control group, but N = 20 ACLR highly competitive subjects, 50% males, age at surgery 26.5 ± 9.4 yrs, height: 176.5 ± 9.4 cm, weight: 76.8 ± 13.9 kg, time post-surgery 4.6 ± 3.0 yrs, IKDC 91.0 ± 9.4

No

Nyland et al. (2014) [56]

N = 65 ACLR; 32 male and 33 females, 5.2 ± 2.9 yrs after surgery; subject group assignments were made based on how they responded to the following question: “Compared to prior to your knee injury how capable are you now in performing sports activities”, very capable (group 1 see field for healthy controls), capable (group 2), or not capable (group 3)

Minimum of 2 yrs since unilateral primary ACL reconstruction with allografts performed by same surgeon, standard rehabilitation program with sufficient adherence

Met or exceeded standard accepted RTS activity goals of a minimum 85% bilateral equivalence with single-leg hop–for–distance testing and 60°/s isokinetic peak knee extensor and flexor torque testing

N = 23 “capable = group 2”, 52.2% males, age at surgery 29.3 [95% CI: 24.1, 34.4] yrs, height: 172.8 [168.4, 177.3] cm, weight: 76.8 [68.3, 85.2] kg, time post-surgery 5.4 [4.2, 6.6] yrs, IKDC 87.2 [82.1, 92.4]

N = 22 “not capable = group 3”, 45.5% males, age at surgery 33.6 [95% CI: 26.4, 39.1) yrs, height: 172.1 [167.1, 177.1] cm, weight: 79.7 [68.0, 91.3] kg, time post-surgery 5.2 [3.8, 6.5] yrs, IKDC 78.6 [71.7, 85.5]

No healthy control group, but N = 20 “very capable = group 1”, 50% males, age at surgery 26.5 [95% CI: 21.9, 31.8] yrs, height: 176.5 [170.4, 180.1] cm, weight: 76.8 [67.4, 80.3] kg, time post-surgery 4.6 [2.8, 6.2] yrs, IKDC 91.0 [84.1, 94.6]

No

Boerboom et al. (2001) [57]

N = 20; N = 10 ACLD (5 copers, 5 non-copers), N = 10 controls

ACLD: ACL rupture confirmed by physical examination and arthroscopy, conservative treatment

Before injury: all ACLD participants at level I (of the IKDC score), after injury: level I (all copers), level II and III (non-copers)

N = 5 copers (all males) with ACLD, median age: 32 yrs, range 21–46 yrs, median time between primary injury and gait analysis 39 months (13–67), acting at same level of sports and daily activities (level I) as before the injury

N = 5 non-copers (3 males, 2 females) with ACLD, with functional instability, median age: 27 yrs, range 23–35 yrs, median time between injury and gait analysis 22 months (16–87), acting at lower level (4 at level III, 1 at level II)

N = 10 healthy males, without a history of knee injury, median age was 22 yrs (range 18–24 yrs)

No in patient groups (age, time between injury and gait analysis); in comparison with healthy controls: n.m

Bulgheroni et al. (1997) [58]

N = 30 all males; N = 15 with ACLR, N = 10 with ACLD, N = 5 healthy controls

ACLR: BPTB graft

Normal activity

N = 15 males with ACLR, age 25 ± 3 yrs, time after reconstruction: 17 ± 5 months, normal activity

N = 10 males with ACLD, age 27 ± 6 yrs, mean time after injury: 20.4 months after injury (range 8–48 months), knee instability

N = 5 males, healthy controls, age 28 ± 3 yrs, no history of musculoskeletal pathology

n.m.

Gokeler et al. (2010) [59]

N = 20; N = 9 ACLR patients, N = 11 healthy controls

ACLR: 6 months after surgery, isolated ACL lesion, no major meniscal or cartilage lesion, normal limb alignment, no relevant previous surgery at any other joint of the limbs, same rehab program at same institution, unrestricted RTS allowed after 9 months post-surgery

Level I-II athletes

N = 9 ACLR patients (6 males, 3 females), mean age: 28.4 ± 9.7 yrs, 27 ± 1.5 wk postoperatively (BPTB technique, same surgeon)

n.a.

N = 11 healthy subjects (8 males, 3 females), level I-II athletes,

n.m.

Hansen et al. (2017) [60]

N = 37; N = 18 male patients, N = 19 healthy participants

ACLR: discharged from rehabilitation facility

Ready to return to on-fields sports specific activity

N = 18 male ACLR at the end of their rehabilitation and allowed to running, 7 ± 2 months post-surgery; N = 8 with a BPTB graft, age: 27 ± 7.69 yrs, weight: 80.40 ± 9.44 kg, height: 178.49 ± 7.29 cm; N = 10 with a hamstring graft, age: 26 ± 3.84 yrs, weight: 74.16 ± 7.19 kg, height: 176.89 ± 5.6 cm

n.a.

N = 19 injury-free male controls, age: 35.4 ± 7.8 yrs, weight: 77.6 ± 8.4 kg, height: 179.1 ± 5.6 cm

n.m.

Klyne et al. (2012) [61]

N = 26; N = 15 ACLD, N = 11 healthy controls

ACLD: chronic, unilateral ACL rupture demonstrated with a positive pivot shift and confirmed by orthopedic surgeon, plus a history of subjective stability and a right skill preference in the lower limb, without previous ACL surgery

Active in at least one sport

N = 15 ACLD, 10 males and 5 females, age: 28 ± 7 yrs, average time since injury 34 months (± 17 months), sustained injury while playing sport

n.a.

N = 11 healthy controls, 9 males, 2 females (age: 29 ± 8 yrs), active in at least one sport, no other musculoskeletal problems, right skill preferred in their lower limb, matched for age and activity level

n.m.

Knoll et al. (2004) [62]

N = 76; N = 25 ACLR (pre- and postsurgery), N = 51 healthy controls

No previous injury, no meniscal damage, BPTB graft, rehabilitation program

Non-professional athletes pursuing some sports 2-3x/wk

N = 25 with ACLD (before surgery, later ACLR), 18 males, 7 females; first subgroup: 9 male with acute ACLD (mean age: 29.86 ± 6.52 yrs, mean height: 1.77 ± 0.8 m, mean mass: 81.40 kg ± 9.06 kg); second subgroup: 9 males with chronic ACLD (mean age: 39.70 ± 2.1 yrs, mean height: 1.70 ± 0.21 m, mean mass: 88.1 ± 20.2 kg) and 7 females with chronic ACLD (mean age: 30.31 ± 9.48 yrs, mean height: 1.64 ± 0.32 m, mean mass: 62.0 ± 8.4 kg). The chronic ACLD group was examined an average of 28.2 months after injury (ranging from 24 to 52 months), but before surgery

Same population of ACLD, but after surgery ACLR, measured at wk 6, and 4, 8, and 12 months post-surgery

N = 51 healthy controls, 31 males, 20 females, mean age: 31.70 ± 4.1 yrs, mean height: 1.71 ± 0.12 m, mean mass 72.1 ± 25.2 kg, no pathology that would affect gait, unfamiliar with treadmill walking

n.m.

Kuster et al. (1995) [63]

N = 33; N = 21 with ACLD, N = 12 healthy controls

ACLD: arthroscopically confirmed complete ACL ruptures at least 1 year previously

ACLD: TAS range 6–10 (mean 8.2) before injury and range 3–9 (mean 5.3) after injury; controls: TAS range 4–8 (mean 6.1)

N = 19 with 21 ACLD, mean age: 28.2 yrs (range 19–42 yrs), mean height: 174.1 cm (156–187.6 cm), mean weight: 77.9 kg (50–112 kg), mean time since injury 45 months (range of 12–108 months), mean Lysholm score 82 (range 55–100)

n.a.

N = 12 healthy controls, similar in height and weight, mean height: 171.2 cm; weight 70.8 kg, no lower limb injury

Unclear (similar for height and weight)

Madhavan and Shields (2011) [64]

N = 24 females; N = 12 with ACLR, N = 12 healthy controls

Complete reconstruction of the ACL with BPTB or HS autograft, ability to climb stairs without difficulty, full joint ROM, SR-36, KOOS, IKDC

Regular physical activity, TAS

N = 12 females ACLR, age: 22.4 ± 2.4 yrs, mean time from surgery 3.7 ± 1.8 yrs, weight: 144.1 ± 19 kg, height: 164.5 ± 5.28 cm, TAS (current) 7.1 ± 2.4

n.a.

N = 12 healthy females, no previous history of knee pathology, age: 24.1 ± 3.2 yrs, weight: 136.5 ± 20.3 kg, height: 163.8 ± 7.3 cm, TAS (current) 6.9 ± 2.1; matched to age

No

Ortiz et al. (2008) [65]

N = 28 females; N = 13 ACLR, N = 15 non-injured controls

Not controlled for graft/surgery or rehabilitation protocol (only similarities); at least 1-year post surgery, no multiple surgeries on the same knee

Recreational fitness activities such as jogging, running, and weightlifting, none of the participants formed part of any intercollegiate, varsity, or competitive sport team

N = 14 physically active young women with ACLR (age: 25.4 ± 3.1 yrs; height: 167.5 ± 5.9 cm; body mass: 63.2 ± 6.7 kg; mean time after surgery 7.2 ± 4.2 yrs (1–16 yrs after reconstruction); N = 9 with BPTB graft, N = 3 with gracilis-ST-graft, N = 2 with Achilles tendon graft; N = 1 excluded due to inability to perform tasks

n.a.

N = 15 healthy, noninjured young women from physiotherapy school (age: 24.6 ± 2.6 yrs; height: 164.7 ± 6.5 cm; body mass: 58.4 ± 8.9 kg

n.m.

Ortiz et al. (2011) [66]

N = 28 females; N = 13 ACLR, N = 15 non-injured controls (same group as for Ortiz et al., 2008 [65])

Not controlled for graft/surgery or rehabilitation protocol (only similarities); at least 1-year post surgery, no multiple surgeries on the same knee

Recreational fitness activities such as jogging, running, and weightlifting, none of the participants formed part of any intercollegiate, varsity, or competitive sport team

N = 14 physically active young women with ACLR (age: 25.4 ± 3.1 yrs; height: 167.5 ± 5.9 cm; body mass: 63.2 ± 6.7 kg; mean time after surgery 7.2 ± 4.2 yrs (1 − 16 yrs after reconstruction); N = 9 with BPTB graft, N = 3 with gracilis-ST-graft, N = 2 with Achilles tendon graft; N = 1 excluded due to inability to perform tasks

n.a.

N = 15 healthy, non-injured young women from physiotherapy school (age: 24.6 ± 2.6 yrs; height: 164.7 ± 6.5 cm; body mass: 58.4 ± 8.9 kg

n.m.

Patras et al. (2012) [67]

N = 28 males; N = 14 ACLR and N = 14 healthy controls

ACLR: performed sub-acutely within 6 months after the injury from the same surgeon (range 1 to 4 months), unilateral ACL tear confirmed by MRI and arthroscopy; full RTS allowed 6 months post-surgery

Competitive soccer players

N = 14 ACLR with BPTB autograft, age: 24.8 ± 5.3 yrs, weight: 77.3 ± 7.5 kg, height: 177 ± 5.3 cm, mean time since surgery 18.5 ± 4.3 months; TAS 8 (range 7–9), Lysholm score 95 (range 94–100)

n.a.

N = 14 healthy male controls, age: 21.7 ± 4.4 yrs, weight: 72.2 ± 8.3 kg, height: 180 ± 9.0 cm

n.m.

Swanik et al. (1999) [68]

N = 24 females, mean age: 29.4 ± 10.4 yrs; mean height: 168 + 10.7 cm; mean weight: 61.2 ± 6 kg; N = 6 ACLD, N = 12 ACLR, N = 6 controls

Complete unilateral ACL tear, ACLR: BPTB grafts, testing 6–30 months after surgery, rehabilitation program completed, attempt to previous level of activity

Recreational activity at least for healthy controls, TAS of experimental groups 6.8 ± 1.5 points, Lysholm Knee Scoring Scale of experimental groups 92.9 ± 5.4

N = 6 females with ACLD

N = 12 females with ACLR

N = 6 females, healthy controls, recreational activity, no previous history of knee pathology, dominant limb (leg to kick a ball with)

n.m.

Zebis et al. (2017) [69]

N = 1 female, age: 21 yrs

Non-contact ACL injury (video-recorded) in the right knee during match play, ST-gracilis graft, standardized rehabilitation

Elite soccer player

N = 1 female elite soccer player at high level with no previous history of ACL injury

n.a.

Screening of elite soccer players pre-season

n.a.