Details of the primary studies for functionality and joint ROM

StudyTreatmentBiofeedback modeEMG deviceOutcome parameterOutcome valuesES
EMG FB GroupControl Group
[16]

8 weeks (daily)

  • Isometric contraction VL (2 × 5–20 s, 5 s rest)

  • Isometric contraction VM (2 × 5–20 s, 5 s rest)

  • Isometric contraction BF (2 × 5–20 s, 5 s rest)

  • Isometric contraction SM (2 × 5–20 s, 5 s rest)

Visual

  • EMG activity VL

  • EMG activity VM

  • EMG activity BF

  • EMG activity SM

Myomed 134KOOS ADLPre:
29.92 ± 11.72
Post:
66.83 ± 7.40		Pre:
27.74 ± 9.62
Post:
64.05 ± 8.48		0.35
KOOS sport and recreation functionPre:
6.37 ± 5.26
Post:
88.41 ± 8.57		Pre:
7.03 ± 6.51
Post:
83.24 ± 9.29		0.58*
KOOS quality of lifePre:
27.45 ± 7.38
Post:
90.54 ± 10.39		Pre:
29.63 ± 5.72
Post:
88.76 ± 9.54		0.18
[21]

8 weeks (2 times per week)

  • Gym ball exercises (10 s hold, 5 s rest, 10 reps)

Not specified

  • EMG activity RA

Myomed 932MODQPre:
32.00 ± 5.02
Post:
2.66 ± 3.04		Pre:
32.04 ± 4.73
Post:
6.80 ± 3.44		1.28*
[17]

8 weeks (12 × 15 min sessions)

  • Isometric contraction QF (15 s contraction, 10 s rest, 15 min in total)

Visual & acoustic

  • EMG activity VM

MyoTrac InfinitiWOMAC stiffnessPre:
1.8 ± 1.7
Post:
1.2 ± 1.2		Pre:
2.3 ± 1.6
Post:
1.7 ± 1. 1		0.43
WOMAC functionPre:
19.8 ± 13.0
Post:
14.6 ± 10.7		Pre:
22.4 ± 11.6
Post:
17.8 ± 9.4		0.32
Lequesne walkingPre:
1.7 ± 1.5
Post:
1.2 ± 1.2		Pre:
1.6 ± 1. 1
Post:
1.3 ± 0.8		0.10
Lequesne ADLPre:
3.7 ± 1.8
Post:
3.1 ± 1.6		Pre:
3.6 ± 1.3
Post:
3.0 ± 1. 1		0.07
[18]

3 weeks (3 times every day)

  • Quadriceps isometric (10 reps)

  • Mini squatting (10 reps)

  • Four-way straight leg raising (10 reps)

  • Knee terminal extension (10 reps)

Visual & acoustic

  • EMG activity VM

  • EMG activity VL

Myomed 932WOMAC stiffnessPre:
4.31 ± 1.7
Post:
3.42 ± 1.57		Pre:
4.15 ± 1.81
Post:
3.0 ± 8.07		0.07
WOMAC functionPre:
49. 1 ± 12.44
Post:
33.42 ± 11.74		Pre:
47.6 ± 0.07
Post:
32.45 ± 9.08		0.09
NHPS physical mobilityPre:
45.03 ± 21.46
Post:
28.10 ± 17.08		Pre:
37.59 ± 21.15
Post:
25.33 ± 18.41		0.16
[19]

4 weeks (2 times per week)

  • Stretching and strengthening (2 × 8 reps)

  • Shoulder rotators, adductors, abductors, extensors with particular attention to supraspinatus

Visual

  • EMG activity SP

  • Muscle balance

  • Muscle relaxation

mDurance systemROM abductionPre:
100.8 ± 3.8
Post:
114.5 ± 5.8		Pre:
100.7 ± 3.4
Post:
109.8 ± 2.6		1.03*
ROM external rotationPre:
59.6 ± 6.9
Post:
74.0 ± 3.2		Pre:
59. 1 ± 7.9
Post:
66.9 ± 7.2		1.29*
[20]

6 weeks (3 times per week)

  • Shoulder flexion strengthening in a video game (5 s contraction, 5 s rest, 10 reps)

Visual & acoustic

  • EMG activity AD

NeuroTrac MyoPlus4 ProROM flexionPre:
121. 11 ± 17.45
Post:
137.50 ± 18.16		Pre:
118.88 ± 23.92
Post:
135.55 ± 19.47		0.10*
ROM abductionPre:
121.82 ± 21.96
Post:
133.64 ± 18.17		Pre:
109.57 ± 25.35
Post:
127.89 ± 18.24		0.32
ROM external rotationPre:
45.83 ± 9.74
Post:
58.89 ± 6.76		Pre:
45.00 ± 10.58
Post:
59.17 ± 6.69		0.04
ROM internal rotationPre:
30.83 ± 5.05
Post:
35.83 ± 6.02		Pre:
28.44 ± 6.42
Post:
37.50 ± 4.92		0.30

* Significant effects between EMG FB Group and Control Group post intervention. ES: effect size; VL: vastus lateralis muscle; VM: vastus medialis muscle; BF: biceps femoris muscle; SM: semimembranosus muscle; RA: rectus abdominis muscle; KOOS: Knee Injury and Osteoarthritis Outcome Score; MODQ: Modified Oswestry Disability Questionnaire; WOMAC: Western Ontario and McMaster Universities osteoarthritis index; ADL: activities of daily living; NHPS: Nottingham Health Profile Score; AD: anterior deltoid muscle; SP: supraspinatus muscle; ROM: range of motion