Parkinsonism is characterized by the triad: bradykinesia, resting tremor, and rigidity. Posture instability is sometimes added as an additional core symptom. In young people this symptom is not often present, but in the elderly, it sometimes plays an important role.
Bradykinesia
Bradykinesia (delay of movements) and akinesia (absence of movements) are the most common and sometimes the only manifestation of parkinsonism. In parkinsonism, automated movements are reduced or absent. Many movements are automated, e.g., eye blinking, facial expression, swallowing saliva, volume and intonation of the voice, arm swing when walking etc. etc.
Bradykinesia is therefore expressed in general diminishment and delay in movements. In addition, there is a monotonous speech with less articulation and less volume, reduced facial expression with sometimes a slightly open mouth, rapid fatigue, and weakness in the muscles, bent posture, walking slowly with small steps and reduced arm swing. Sometimes salivation occurs because the saliva is insufficiently swallowed and there is dysarthria or dysphagia.
Rest tremor
A resting tremor is a slow tremor (3 to 6 Hz) with a large amplitude, the characteristic pill-rolling tremor. Often one or both hands are affected, but also the head, legs or the whole body can participate. Jaw tremor has a specific name: rabbit syndrome and may be confused with orofacial tardive dyskinesia.
The severity of the resting tremor often increases by walking or other activities and by emotional stress and is suppressed by intentional movements such as reaching for a glass. However, when the glass is held, a rest position is restored, and the tremor starts again.
Sometimes the parkinsonism is also accompanied by a postural tremor (also called action tremor) which is a faster tremor, often with a smaller amplitude than the resting tremor. Postural tremor arises when assuming a posture against gravity, such as with outstretched arms.
Rigidity
Rigidity is a sustained increased tone of the muscles. This makes the muscles feel stiff and tense continuously or intermittently. When passively moving the muscles, it feels like bending a lead pipe. Rigidity is often more clearly present in larger flexor muscle groups. Sometimes, while bending, the researcher feels rhythmic interruptions, the cogwheel phenomenon. This may not be a separate phenomenon, but a tremor suppressed by rigidity.
Rigidity gives complaints such as sensitivity of the muscles, stiffness, muscle or joint pain, or too little coordination in sports.
Posture instability
Postural instability can hinder walking, especially in the elderly. Postural instability can be tested with the pull test in which the examiner, standing behind the patient, unexpectedly jerks the shoulders back (after explanation, of course). Postural instability results in a reduced or absent postural reflex.
Publications
Pieters LE, Bakker PR, van Harten PN. Asymmetric Drug-Induced Parkinsonism and Psychopathology: A Prospective Naturalistic Study in Long-Stay Psychiatric Patients. Frontiers in psychiatry 2018; 9: 18.
van Harten, P. N. . Acute bewegingsstoornissen door medicijnen. Tijdschrift voor Psychiatrie. 2003; 45(5), 251-264.
Van Harten, P. N. Atypische antipsychotica en de kans op extrapiramidale bijwerkingen. Tijdschrift voor Psychiatrie. 2001; 43(11), 767-776.