2.2. Procedures
tremor, rigidity, Parkinson’s disease, orthosis, UL dexterity
The calculation of the sample size was based on the tremor and rigidity improvement as the main variables of the study. Given alpha risk of 0.05 and a beta risk of 0.20, in bilateral contrast, it is estimated that 40 participants (20 for each group) were required to detect a minimum difference of 0.50 in the rigidity and tremor scores of the most affected UL using the unified Parkinson’s disease rating scale, motor subscale part III (UPDRS) [Using the Epidat 4.2 program, participants were randomly assigned to the experimental group (EG) or the control group (CG). The EG treatment protocol consisted of implementing the DEFO in the most affected UL for two months (intervention period), whereas subjects in the CG led life as usual during the first two months (control period). One month prior to the implementation of the DEFO, measurements of the size and posture of the UL were conducted for the customization of the orthosis in the participants of both groups. At the first visit, the sociodemographic and clinical data of the participants were collected, and their fulfilment of the inclusion criteria was ensured. The participants were instructed to maintain their prescribed dopaminergic medication regimen. The effects of the DEFO were evaluated during the ON state (under the benefit of levodopa) and during the OFF state (1 h before the next levodopa intake).Motor assessments were conducted in the EG, at the end of the DEFO implementation period. Then, the DEFO was withdrawn and a second assessment was conducted two months later to evaluate if a carry-over effect was maintained during that time (Several assessment tools were administered to evaluate the functional activity, quality of life, and manual dexterity of the subjects.To obtain the primary outcomes, the unified Parkinson’s disease rating scale subscale II (UPDRS) was administered to assess functional activity consisting of 13 items. The score for each item is from 0 (normal) to 4 (worst), with a maximum score of 52 points, where higher scores indicate worse functional activity [For the assessment of UL dexterity, different motor aspects were evaluated. Subscale III of the UPDRS was administered, consisting of 17 items with a score range from 0 to 4 (from normal symptomatology to the most severe impairment), with a maximum score of 68 [Finally, the Purdue board test (PPT), the Minnesota manual dexterity test (MMDT) and the squares test (ST) were used to assess manual dexterity. The PPT consists of a two-column board that includes of 25 holes each, together with pins, washers, and rings located in four semicircles at the top of the board. The test is composed of four subtests that must be performed a total of three times, so that the total score is the average score obtained from the three attempts at each subtest. Thus, higher scores indicate better manual dexterity [