Table 1. Study characteristics.
| Author, year | Participants | Sessions | FES-cycling application | Experimental group design | Control group design |
|---|---|---|---|---|---|
| Krause et al., 200835 | Study design: Randomized crossover trial Sample size: 5 Sex (M/F): 3/2 Mean age: 46.6 ASIA: A Level of injury, number/ Range: T /(T3–T7) Duration of injury Mean (Range): 6.2 years (3–9 years) |
Sessions (n): 10 Session duration: 60–100 min Frequency: – Time period: – |
Type: Microstim 8 (Krauth & Timmermann, Germany). Pulse: Biphasic rectangular pulses. Pulse width: 500 ms Frequency: 20 Hz Amplitude: 0 to 99mA Electrodes: 12 (Flextrodes, 5*9 rectangle) Target muscles: quadriceps, hamstrings and glutei muscles. RPM: – |
FES cycling The participants legs were moved by the FES applied to the leg while fastened to the ergometer. |
Passive cycling The participants legs were moved only by the engine of ergometer with same frequency and with the same period of time, FES was not applied. First 5 sessions participants underwent FES cycling (experimental phase) then 5 sessions of passive cycling (control phase). Other participants performed same treatment protocol but in reverse order (crossover design). |
| Kuhn et al., 201430 | Study design: Clinical cohort study Sample size: 30 Sex (M/F): 30/0 Mean age: 44 ASIA: A=10, B=3,C=15, D=2 Level of injury, number/ Range: C=13, T=11, L=6/(C4–L4) Duration of injury Mean (Range): 8.4 months (0–112 months) |
Sessions (n): 8 Session duration: 20 min Frequency: 2–3 times weekly Time period: 4 weeks |
Type: Computer-controlled leg cycle (RECK-Medizintechnik GmbH &Co. KG, Betzenweiler, Germany) Pulse: Biphasic rectangular pulses Pulse width: 250 ms Frequency: 30 Hz Amplitude: 10–130 mA Electrodes: 6 (Self-adhesive 5*9 cm) Target muscles: hamstring, quadriceps, and the gluteal muscles. RPM: 15–55 |
FES cycling: The range of the pedalling cadence was set between 15–55 rpm. When could not reached minimum cadence actively, the pedalling was achieved passively by motor power. When cadence exceed 55 rpm, the resistance was adjusted manually (3 W). On days without FES cycling, the participants received physiotherapy and occupational therapy for 45 min. The physiotherapy intervention focused on proprioceptive neuromuscular facilitation (PNF) techniques, whereas occupational therapy interventions were focused on activities of daily life. |
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| Mazzoleni et al., 201732 | Study design: Pilot Sample size: 7 Sex (M/F): 5/2 Mean age: 45.3 ASIA: A Level of injury, number/ Range: T/(T4–T12) Duration of injury Mean (Range): NA |
Sessions (n): 40 Session duration: – Frequency: 3 times weekly Time period: – |
Type: FES cycling system (Pegaso, Biotech Srl, Italy). Pulse: Square biphasic alternated pulses Pulse width: 500 ms Frequency of 50 Hz Amplitude: 35-75 mA (Quadriceps), 25-50 mA (Biceps femoris) Electrodes: – Target muscles: quadriceps and biceps femoris muscles. RPM: – |
The patients received 20 sessions of FES cycling, an integrated cycle-ergometer system based on an electronic control, followed by 20 training sessions based on an over-ground robotic exoskeleton (Ekso GT, Ekso Bionics,USA). | – |
| Mazzoleni et al., 201331 | Study design: Pilot Sample size: 5 Sex (M/F): 4/1 Mean age: 43 ASIA: A=1, B=2, C=2 Level of injury, number/ Range: C=2, T=3/(C7–T12) Duration of injury Mean (Range): NA |
Sessions (n): 20 Session duration: 15 min, 5 min were incrementally added, till to 30 min Frequency: 3 times weekly Time period: 7 weeks |
Type: FES cycling system (Pegaso, Biotech Srl, Italy). Pulse: Balanced biphasic pulse; timing: 50–500 μs Pulse width: – Frequency: – Amplitude: 140 mA Electrodes: 6 Target muscles: quadriceps, femoral biceps and gluteus muscles. RPM: – |
Each session was included the following four phases: (1)Warm-up (90 sec, maximum speed: 40 cycles/min); (2) Preparation (2 min, maximum stimulation: 30%); (3) Active phase (30 min, target speed: 30 cycles/min, resistance: 5 Nm); (4) De-fatigue (20 sec, speed kept by motor: 20 cycles/min). In addition to FES cycling, rehabilitation intervention using exercises to increase control movement of the head, arm and trunk. |
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| Ralston et al., 201336 | Study design: Randomized crossover trial Sample size: 14 Sex (M/F): 11/3 Mean age: 25 ASIA: A=13, B=1 Level of injury, number/ Range: C=8, T=6/(C4–T10) Duration of injury Mean (Range): 118 days (64–135 days) |
Sessions (n): 20 Session duration: 30-45 min Frequency: 4 times weekly Time period: 5 weeks |
Type: Microstim 8 (Krauth & Timmermann, Germany). Pulse: Biphasic rectangular pulses. Pulse width: 350 ms Frequency 33 Hz Amplitude: 140 mA Electrodes: – Target muscles: quadriceps, hamstrings, and gluteal muscles. RPM: – |
First group received FES cycling + usual rehabilitation. Usual rehabilitation included physiotherapy and occupational therapy for 2 weeks. Second group received usual rehabilitation only. Next 3 weeks the first group received usual rehabilitation only. Second group received FES cycling + usual rehabilitation. | – |
| Reichenfelser et al., 201334 | Study design: Pilot Sample size: 9 Sex (M/F): NA Mean age: NA ASIA: Incomplete (B,C, and/ or D) Level of injury, number/ Range: Paraplegia (T2–L5) Duration of injury Mean (Range): NA |
Sessions (n): 7–14 Session duration: 30 min Frequency: 3 times weekly Time period: 2 months |
Type: tricycle (AnthroTech, Eckental, Germany) Pulse: Rectangular biphasic pulses Pulse width: 600 ms Frequency of 50 Hz Amplitude 20 mA Electrodes: 10 Target muscles: quadriceps, hamstring, and gluteus muscles RPM: 10,20,30,40,50, and 60 |
Training session included: Spasticity test routine Warm-up (5 min) Isokinetic training (5 min) Power output test Constant torque training (5 min) Isokinetic training (5 min) Spasticity test routine |
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| Reichenfelser et al., 201233 | Study design: Pilot Sample size: 23 Sex (M/F): 20/3 Mean age: 40 ASIA: B=4, C=10, D=9 Level of injury, number/ Range: C=9, T=9, L=5/(C4–L1) Duration of injury Mean (Range): 9 months (1–29 months) |
Sessions (n): 18 Session duration: 30 min Frequency: 3 times weekly Time period: 2 months |
Type: tricycle (AnthroTech, Eckental, Germany) Pulse: Rectangular biphasic pulses Pulse width: 600 ms Frequency: 50 Hz Amplitude: 20 mA Electrodes: (Axelgaard CF5090, 2 * 9 cm, Fallbrook, California). Target muscles: quadriceps, hamstrings and gluteus muscles. RPM: 10,20,30,40,50, and 60 |
Training session included: Spasticity test routine (3 min) Warm up (5 min) Isokinetic training (5 min) Active power output test Constant torque training (5 min) Isokinetic training (5 min) Spasticity test routine (3 min) |
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| Sadowsky et al., 201319 | Study design: Retrospective cohort study Sample size: 45 Sex (M/F): 38/7 Mean age: 36 ASIA: A=31, B=9, C=5 Level of injury, number/ Range: Quadriplegia (C1–T1) = 28, Paraplegia (T2–L5) = 17 Duration of injury Mean (Range): 23 patients = 6 months-5 years, 22 patients = more than 5 years |
Sessions (n): 36 Session duration: 45–60 min Frequency: 3 times weekly Time period: 30 months |
Type: ERGYS2 (Therapeutic Alliances Inc., Fairborn, OH, USA) Pulse: – Pulse width: 500 ms Frequency: 100 Hz Amplitude: 140 mA Electrodes: – Target muscles: quadriceps, gluteal, and hamstring muscles. RPM: 50 |
Participants underwent FES cycling with bilateral reciprocal leg cycling, typically at 50 RPM | Standard care: received range of motion and stretching. |
| Szecsi and Schiller 200914 | Study design: Pilot Sample size:13 Sex (M/F):9/4 Mean age: 39.9 ASIA: A Level of injury, number/ Range: C7–T12 Duration of injury Mean (Range): 10.1 years (–) |
Sessions (n): 3 Session duration: 20 min Frequency: – Time period: 2 weeks |
Type: – Parameters: LFRP (rectangular, biphasic, charged balanced pulses with a frequency of 20 Hz, maximum pulse amplitude of 127 mA, and constant pulse width of 500 μs). And MFAC (4 KHz sinusoidal modulated with 50 Hz on-off rectangles and duty cycle of 1:1). Electrodes: 4 (auto-adhesive gel electrodes 4.5 × 9.5 cm,Hamburg, Germany) Target muscles: quadriceps, gluteal, and hamstring muscles. RPM: 35–55 |
Each participant underwent 3 different experimental sessions: (1) isometric torque generation using LFRP and MFAC stimulation; (2) ergometer using LFRP stimulation; (3) ergometer using MFAC stimulation. The order of the sessions 1, 2, and 3 was randomized; each session was performed on a different day |
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| Yaşar et al., 201523 | Study design: Pilot Sample size: 10 (1 non traumatic SCI) Sex (M/F): 6/4 Mean age: 37.5 ASIA: C=1, D=9 Level of injury, number/ Range: C=5, T=5/(C4–T12) Duration of injury Mean (Range): 27.4 months (24–33 months) |
Sessions (n): 48 Session duration: 60 min Frequency: 3 times weekly Time period: 16 weeks |
Type: (RT 300-SLSA; Restorative Therapies, Baltimore, MD, USA). Pulse: – Pulse width, 250 ms Frequency: 20 Hz Amplitude: 10–140 mA. Electrodes: 6 (3 * 4 cm2 adhesive surface electrodes) Target muscles: quadriceps, hamstrings and gluteal muscles. RPM: 40–50 |
Participants underwent FES cycling. The participants were warned not to make any voluntary muscle contraction during cycling and the lower extremities were passively moved. The range of pedalling cadence was 40–50 rpm | – |
Notes: C, cervical; T, thoracic; L, lumber; ASIA, American spinal cord association; SCI, spinal cord injury; NA, not available; M, male; F, female; LFRP, low frequency rectangular pulse; MFAC, middle-frequency alternating current; RPM, rotations per minute.