Persons with C5 or C6 tetraplegia achieve selected functional gains using a neuroprosthesis.

OBJECTIVE

To test the efficacy and safety of the NESS Handmaster neuroprosthesis with subjects with C5 or C6 tetraplegia.

DESIGN

Interventional, nonrandomized case series.

SETTING

Subjects' residence and university research laboratory.

PARTICIPANTS

Men, 3 to 17 years after C5 (n=5) and C6 (n=2) spinal cord injury (SCI).

INTERVENTION

Subjects practiced with the neuroprosthesis daily to regain grasp, hold, and release ability and to restore selected functions of 1 of the 2 paralyzed hands. Subjects were observed 2 to 3 times weekly for 3 weeks.

MAIN OUTCOME MEASURES

Three activities of daily living (ADL) tasks: (1) pick up a telephone, (2) eat food with a fork, and (3) perform 1 individually selected ADL task and 2 grasp, hold, and release tasks (lift a videocassette, lift a 150-g weight). Secondary outcomes were grip strength, electrically induced finger motion, and Fugl-Meyer spherical grasp. Nonparametric data were analyzed with the Wilcoxon signed-rank test, and parametric data (grip strength and finger motion) were analyzed by analysis of variance. All tests were considered significant at P equal to.01.

RESULTS

At study completion, all 7 subjects were 100% successful at using the Handmaster in the studied ADL and grasp, hold, and release tasks. Significant improvements occurred in grip strength (from.57+/-.98N at baseline to 16.5+/-4.4N), finger linear motion (from 0.0cm at baseline to 8.4+/-3.2cm), and Fugl-Meyer scores. No safety issues were encountered. Six of 7 subjects rated their overall performance as "excellent."

CONCLUSIONS

The Handmaster is a safe, noninvasive neuroprosthesis that improves hand function of selected subjects with C5 or C6 SCI.