Differences in muscle strength in parkinsonian patients affected on the right and left side.

BACKGROUND: Muscular weakness is a frequent cause of instability that contributes to falls in Parkinson's disease (PD). Isokinetic dynamometry is a method of muscle assessment useful to measure the muscular strength giving a quantification of the weakness, but only few studies about isokinetic assessment were performed in PD. The aims of the study were to evaluate the muscle strength in PD and to investigate the differences in patients affected on the right and left side. METHODS: Knee flexor and extensor muscles strength was assessed using an isokinetic dynamometer in 25 patients in stage 3 H&Y and in 15 healthy controls. Subjects were tested in both legs at three fixed angular velocities: 90°/s, 120°/s, 180°/s. RESULTS: Considering the whole population of Parkinsonians, no difference in strength was observed with respect to controls. Considering the side, patients affected on the right side showed a clear tendency to be weaker than patients affected on the left side and controls. CONCLUSIONS: PD patients affected on the right side, but not those affected on the left side, had a reduction in muscle strength as compared to controls. We postulate a central origin deficit in muscle strength in PD. It is known that dopamine transporter binding is more severely reduced in the left posterior putamen and our results suggest that the control of the muscle strength in PD is linked to the right-left hemispheric asymmetry of the functional organization of basal ganglia and with their connections to cortical motor and pre-motor areas.

Effectiveness of intensive inpatient rehabilitation treatment on disease progression in parkinsonian patients: a randomized controlled trial with 1-year follow-up.

BACKGROUND: Rehabilitation treatments have acute beneficial effects in Parkinson's disease (PD) patients, but whether the effects persist over time is unclear. OBJECTIVE: To assess whether an intensive rehabilitation treatment (IRT) is effective in improving motor performance compared with a control group in a 12-month follow-up, to investigate whether a second cycle administered after 1 year has the same efficacy as the first treatment, and to determine whether IRT reduces the need for increasing levodopa dosage. METHODS: A total of 50 PD patients were randomly assigned to 2 groups; 25 participants had 4 weeks of inpatient physical therapy that included treadmill and stabilometric platform training. At discharge, these patients were invited to continue doing the learned exercises. After 12 months, the same treatment was repeated. The control group of 25 patients received only pharmacological treatment and was invited to practice generic physical exercise at home. The rating scales used for the clinical evaluation were the Unified Parkinson's Disease Rating Scale Sections II and III (UPDRS II and III) and total (UPDRS tot). RESULTS: The authors found that the beneficial effects of IRT persisted over time. A second rehabilitation cycle administered after 1 year was as effective as the first treatment. At the end of the study, daily medication dosage was reduced in treated patients, whereas it was significantly increased in control patients. CONCLUSION: These findings suggest that the natural worsening of symptoms associated with PD can be effectively counteracted by a properly designed IRT.