Details of studies in neuromuscular electrical stimulation to assist with muscle strength and function (lower limb) section
| Reference | Study design | Age range (years) | n | Muscles stimulated | Results | Session duration, frequency and mode |
|---|---|---|---|---|---|---|
| Daichmann et al5 | Case study | 13 | 1 | Right QR | Increase in right QR strength, decrease in right HS spasticity, improvements in mobility elements of PEDI results | Approximately 30 min every other day for 6 weeks. Exercise only |
| Al-Abdulwahab et al6 | Pre/post test design. Data compared with healthy (n=20) and control CP (n=10) groups | 7.4±2 | 21 | GM bilaterally | ↑↑Temporal spatial parameters (apart from step width) and ↓↓hip adductor tone of the treated group | 15 min three times per day for 7 days. Stimulation applied mainly during walking but not timed to the gait cycle |
| Postans and Granat7 | ABAB | 8.9–17.5 | 8 | DF, PF, QR (determined through gait analysis) | For NMES to AF only group (n=5), clinically significant changes in stance phase kinematics for three children | Used functionally during testing on 2 days |
| Orlin et al8 | AB | 7.9–11.8 | 8 | Percutaneous stimulation of TA and GA of involved limb | ↑*Peak DF in swing (more affected extremity) and DF at initial contact (less affected extremity) for TA+GA condition. Trends of improvement in DF kinematics seen for TA and GA only conditions | Used functionally for 1 week for each NMES set up (TA only, TA and GA, and GA only) for approximately 2 × 45 min daily. Four-channel and two-channel stimulation used for diplegic and hemiplegic children, respectively |
| Pierce et al12 | Comparison of surface and percutaneous stimulation | 11 | 1 | DF with balanced eversion and inversion | Increases in DF at initial contact, peak in swing and mean in swing, greater with percutaneous stimulation. Ankle absorption work improved (decreased) with both types of stimulation. Ankle generation work increased only with percutaneous stimulation. Greater isometric force produced with percutaneous than surface stimulation | Assessed functionally during walking (one test day) |
| Khalili and Hajihassanie18 | Randomised (within child), one child dropped out | 11.6–14 | 11 | QR | Marginal improvement in HS spasticity and passive knee extension | 30 min three times per week for 4 weeks. Exercise only |
| Katz et al19 | Case controlled | 2.8–4.1 | 5 | Right QR | (Seated tests) ↑average motion velocity and a decrease in motion jerk and in knee torque after training; ↓QR–HS co-contraction following training, but not during stimulated assisted motion | 30 min daily for 3 months. Exercise only. Stimulation also used orthotically during tests |
| Stackhouse et al20 | Group comparisons. NMES (n=6); volitional control (n=5); one child in NMES group excluded from analysis | 8–12 | 11 | Percutaneous stimulation of QS and TS | ↑TS maximum voluntary isometric contraction normalised to body weight for NMES group compared with volitional group, ns for QS. ↑Walking speed for NMES group, ns walking speed for volitional group following intervention | 15 min for each muscle group, three times per week for 12 weeks. Exercise only |
| Kerr et al21 | Randomised (NMES n=18; placebo n=22; and TES n=20) | 5–16 | 60 | QR (vastus medialis) bilaterally | For NMES: ns in strength or function compared with placebo; ↓impact of disability at end of treatment (not at 6-week follow-up) | NMES: 1 h daily 5 days per week for 16 weeks. Exercise only |
| Van der Linden et al22 | Randomised (NMES n=7; control n=7); one child (NMES group, QS) dropped out | 5–13 | 14 | DF with balanced eversion and inversion and QR | ↑Peak DF angle and foot–floor angle for both groups when comparing walking with and without FES. ↓Walking speed for both groups when comparing walking with and without FES; ns between NMES and control groups in deviation of gait pattern from normal, foot–floor angle, DF in swing angle, or passive DF when comparing before and after intervention results | NMES: 1 h daily to either DF (n=5) or QS (n=2) 6 days per week for 2 weeks. Exercise only. Followed by FES of DF and QR during gait for 8 weeks. Stimulation also used orthotically during tests for both NMES and control groups |
| Durham et al23 | ABA, two children dropped out | 6–15 | 12 | DF | Heel–toe contact pattern and symmetry both improved following intervention with FES (no statistical analysis) | FES of DF during gait for 12 weeks |
| Johnston et al24 | Group comparisons. NMES with limited surgery (n=9); traditional surgery (n=8) | 6–12 | 17 | BF, GM, Gmax, PAM, VL, VM, Sol, TA (not all used in all children) | ns differences in passive range, temporal spatial parameters or gross motor function between groups before or 1 year after intervention. FES group underwent 4.5 fewer ablative procedures per child | 4-week (minimum) exercise for no more than 1 h per day, followed by functional use |
| Hazlewood et al26 | Randomised (NMES n=10; control n=10) | 5–12 | 20 | TA of involved limb | ↑Passive DF in NMES group. ↑Active DF in NMES group compared with control group post intervention but not pre intervention. ↑TA muscle power in NMES group | 1 h daily for 35 consecutive days. Exercise only |
| Comeaux et al27 | ABCA (n=7), ACBA (n=7) | 9.1±3.8 | 14 | GA and TA | ↑*DF during gait for both ‘targeted’ FES interventions | ‘Targeted’ FES of GA during 15-min therapy session three times a week for 4 weeks followed/preceded by a similar programme with GA and TA |
| Van der Linden et al29 | Randomised (NMES n=11; control n=11) | 8.5±2.8 | 22 | GMax | For NMES: ns in hip extensor strength, gait analysis, passive limits of hip rotation, section E of gross motor function measure when comparing NMES group with control group | NMES: 1 h a day 6 days per week for 8 weeks. Exercise only |
| Carmick31 | Case series | 1.6–10 | 3 | TA, TS, GA, Sol, Gmax, HS (not all used in all patients) | Improvements in physiological cost index measured in two children together with observations of improved gait function and symmetry | Approximately weekly sessions of unspecified duration of ‘targeted’ FES for between 6 weeks and 8 months |
| Carmick32 | Case series | 1.7–4.7 | 4 | TA, TS, Gmax, HS (not all used in all patients) | Improvements in heel strike, foot alignment, function, balance, active and passive DF range of movement and walking speed. (Not all observed in all children) | Unspecified frequency and duration of ‘targeted’ FES sessions as required |
| Bertoti et al33 | Case series percutaneous stimulation | 6 | 2 | Gmax, GM, VM, VL, GA, TA | Measured improvements in lower extremity ranges of motion, spatial gait characteristics, improved gross motor function | Two 15-min sessions of FES 5 days per week for between 7 and 10 months. Children asked to ‘work with’ FES |
Skin surface electrodes used unless stated otherwise.
↑↑, ↑, ↑* indicates statistically significant (p<0.001, p<0.05 and p<0.0055, respectively) increase; ↓↓ and ↓ indicates statistically significant (p<0.001 and p<0.05, respectively) decrease; ns indicates no statistically significant difference (p>0.05); ± indicates plus or minus one SD.
AB, baseline-intervention; ABC, baseline-intervention1-Intervention2; ABAB, baseline1-intervention-baseline2-intervention; ABA, baseline-intervention-follow-up; ABCA, baseline-intervention1-intervention2-follow-up; AF, ankle flexors; BF, biceps femoris; CP, cerebral palsy; DF, dorsiflexion; FES, functional electrical stimulation; GA, gastrocnemius; GM, gluteus medius; Gmax, gluteus maximus; HA, hip adductors; HS, hamstrings; NMES, neuromuscular electrical stimulation; PAM, posterior adductor magnus; PEDI, pediatric evaluation of disability inventory; PF, plantarflexion; QR, quadriceps; Sol, soleus; TA, tibialis anterior; TES, threshold electrical stimulation; TS, triceps surae; VL, vastus lateralis; VM, vastus medialis.