1) Goetz CG, Tilley BC, Shaftman SR, et al. Movement Disorder Society UPDRS Revision Task Force: Movement Disorder Society-sponsored revision of the Unified Parkinson’s Disease Rating Scale (MDS-UPDRS): scale presentation and clinimetric testing results. Mov Disord, 2008, 23: 2129–2170. [Medline] [CrossRef]
2) Gunzler SA, Riley D, Walter E, et al.: Comparison of the toe tapping component of the MDS-UPDrs motor scale with leg agility and finger tapping. Mov Disord, 2010, 25, Suppl 2: 348–389.
3) Nieuwboer A, Dom R, De Weerdt W, et al.: Electromyographic profiles of gait prior to onset of freezing episodes in patients with Parkinson’s disease. Brain, 2004, 127: 1650–1660. [Medline] [CrossRef]
4) Dietz V, Quintern J, Berger W, IETZ V: Electrophysiological studies of gait in spasticity and rigidity. Evidence that altered mechanical properties of muscle contribute to hypertonia. Brain, 1981, 104: 431–449. [Medline] [CrossRef]
5) Burleigh A, Horak F, Nutt J, et al.: Levodopa reduces muscle tone and lower extremity tremor in Parkinson’s disease. Can J Neurol Sci, 1995, 22: 280–285. [Medline] [CrossRef]
6) Dietz V, Berger W, Horstmann GA: Posture in Parkinson’s disease: impairment of reflexes and programming: Ann Neurol, 1988, 24, 5: 660–669. [Medline] [CrossRef]
7) Glendinning DS, Enoka RM: Motor unit behavior in Parkinson’s disease: Phys Ther, 1994, 74, 1: 61–70. [Medline] [CrossRef]
8) Pedersen SW, Oberg B: Stretch-shortening contraction in Parkinson patients: evidence of normal muscle contraction execution with low efficiency. Scand J Rehabil Med, 1997, 29: 251–255. [Medline]
9) Elble RJ, Moody C, Leffler K, et al.: The initiation of normal walking. Mov Disord, 1994, 9: 139–146. [Medline] [CrossRef]
10) den Otter AR, Geurts AC, Mulder T, et al.: Speed related changes in muscle activity from normal to very slow walking speeds. Gait Posture, 2004, 19: 270–278. [Medline] [CrossRef]
11) Albani G, Sandrini G, Künig G, et al.: Differences in the EMG pattern of leg muscle activation during locomotion in Parkinson’s disease. Funct Neurol, 2003, 18: 165–170. [Medline]
12) Dietz V, Zijlstra W, Prokop T, et al.: Leg muscle activation during gait in Parkinson’s disease: adaptation and interlimb coordination. Electroencephalogr Clin Neurophysiol, 1995, 97: 408–415. [Medline] [CrossRef]
13) Cioni M, Richards CL, Malouin F, et al.: Characteristics of the electromyographic patterns of lower limb muscles during gait in patients with Parkinson’s disease when OFF and ON L-Dopa treatment. Ital J Neurol Sci, 1997, 18: 195–208. [Medline] [CrossRef]
14) Hallett M, Khoshbin S: A physiological mechanism of bradykinesia. Brain, 1980, 103: 301–314. [Medline] [CrossRef]