On the Use of Wrist Flexion and Extension for the Evaluation of Motor Signs in Parkinson’s Disease

Parkinson’s Disease (PD) is a chronic, progressive and degenerative disease that causes the death of the dopaminergic neurons. Clinically, PD is characterized by tremor, stiffness, slowness in movement and changes in posture, balance, and gait. The hand is one of the regions in the body most affected by bradykinesia due to the evolution of the disease. The Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) is the most widely used clinical scale to follow up the clinical condition of patients. The aim of this work is to review the literature on hand movements included in the MDS-UPDRS Part III (Motor Examination) and also to analyze flexion and extension movements not included in the MDS-UPDRS. The main hypothesis of the study was that flexion and extension movements, not included in the MDS-UPDRS, are important for the clinical evaluation of patients with PD. To verify this hypothesis 23 studies have been identified and analyzed. These studies considered the evaluation of PD motor signs of based on tasks such as finger tapping, hand opening and closing, hand supination and pronation, and hand flexion and extension. The results show that hand flexion and extension are important activities for the assessment of motor signs in people with PD, even though they are not included in the MDS-UPDRS.