A novel functional electrical stimulation treatment for recovery of hand function in hemiplegia: 12-week pilot study

Abstract

Background: Loss of finger extension is common after stroke and can severely limit hand function. Contralaterally controlled functional electrical stimulation (CCFES) is a new treatment aimed at restoring volitional finger and thumb extension. A previous pilot study showed reductions in hand impairment after 6 weeks of CCFES, but the effect did not persist after end of treatment.

Objective: This study aimed to evaluate the feasibility of achieving greater and more persistent gains with CCFES by increasing the treatment period to 12 weeks.

Methods: CCFES uses neuromuscular electrical stimulation to open the paretic hand in direct proportion to the degree of volitional opening of the unimpaired contralateral hand, which is detected by an instrumented glove. Three subjects with chronic hemiplegia participated in a 12-week CCFES treatment, which consisted of daily CCFES-assisted active repetitive hand-opening exercises and twice weekly functional task practice with CCFES.

Results: Maximum voluntary finger extension increased by 101 degrees and 68 degrees for subjects 1 and 2, respectively, but subject 3 had no improvement in finger extension. Box and Block score increased by 6, 15, and 7 blocks, and upper extremity Fugl-Meyer score increased by 11, 15, and 7 points for subjects 1, 2, and 3, respectively. The finger extension gains declined at the 1-month and 3-month follow-up for subjects 1 and 2, but the gains in Box and Block and Fugl-Meyer scores persisted at follow-up.

Conclusions: Greater reductions in hand impairment were achieved by extending the treatment period. The effect and its longevity may be related to baseline impairment level.

Figures

Figure 1. Contralaterally Controlled Functional Electrical Stimulation. Volitional Opening of the Unaffected Hand Produces a Proportional Intensity of Stimulation to the Paretic Hand Extensors

Figure 2. Sum of Joint Angles of the Index Finger (Metacarpophalangeal + Proximal Interphalangeal + Distal Interphalangeal) During Maximum Voluntary Finger Extension

Note: Zero degrees corresponds to a fully extended finger; negative values are flexion. Values are the mean ± standard deviation of 3 repeated measurements.

Figure 3. Finger Movement Tracking Error

Note: Error was the accumulated distance the cursor was from the track over the 30-second period. Values are the mean ± standard deviation of 3 repeated measurements normalized by the maximum error for each subject.

Figure 4. Maximum Isometric Finger Extension Moment

Note: Values are the mean ± standard deviation of 3 repeated measurements.

Figure 5. Box and Block Score, the Number of Blocks Transferred in 60 seconds

Figure 6. Upper-Extremity Portion of the Fugl-Meyer Motor Assessment, With a Maximum Score of 66

Note: Values are the total score.