Development of grip strength during the first year after stroke.

OBJECTIVE: To assess recovery of grip strength during the first year post-stroke.

DESIGN: Exploratory study on a subsample of patients participating in the Norwegian Constraint-Induced Movement Therapy trial.

SUBJECTS: Eleven patients (mean age 59.1 years; 3 women) with mild to moderate stroke were recruited 7-29 days post-stroke.

METHODS: An electronic dynamometer (Biometrics Ltd, Gwent, UK, 2006) was used to assess maximum grip force in 5 hand positions, rate of force development and sustainability of grip force. Similar assessments were performed to assess pinch strength. The participants were assessed 5 times during a 1-year period.

RESULTS: Grip force in the affected hand increased in all handle positions during the 1-year follow-up, mostly during the first 6 months. At 2 and 4 weeks, rate of force development was less than half, and relative sustainability of grip force showed 20-30% greater deficit than for the non-affected hand. The affected hand approached the values of the non-affected hand after 6 months with little further progress until 1-year follow-up.

CONCLUSION: Grip strength in the affected hand improved considerably in the first year post-stroke. Patterns of improvement were similar across tests, i.e. rapid during the first weeks, slower until 6 months, and minimal 6-12 months post-stroke.