Parkinson’s is a disease that is characterised by four major features:
- rest tremor of a limb (shaking with the limb at rest)
- slowness of movement (bradykinesia)
- rigidity (stiffness, increased resistance to passive movement) of the limbs or trunk
- poor balance (postural instability).
When at least two of these symptoms are present, and especially if they are more evident on one side than the other, a diagnosis of Parkinson’s is made, unless there are atypical features that suggest an alternative diagnosis. People may first realise something is wrong when they develop a tremor in a limb; movements are slowed and activities take longer to perform, or they experience stiffness and have balance problems. Initially, symptoms are a variable combination of tremor, bradykinesia, rigidity and postural instability. Symptoms typically begin on one side of the body and spread over time to the other side.
Changes occur in facial expression so that there is a certain facial fixity (blank expression showing little emotion) or a staring appearance (due to reduced frequency of blinking). Complaints of a frozen shoulder or foot drag on the affected side are not uncommon. As symptoms appear gradually, older people may attribute these changes to ageing. The tremor is often thought to be “shakiness”, bradykinesia is regarded as normal “slowing down”, and stiffness is attributed to arthritis. The stooped posture, common to Parkinson’s, may be attributed to age or osteoporosis. Both younger and older people may experience initial symptoms for a year or more before seeking medical evaluation.
Initially the symptoms are mild, usually on one side of the body. Rest tremor is a major characteristic of Parkinson’s, and the most common presenting symptom, but some people never develop it.
Tremor may be the least disabling symptom, but is often the most embarrassing to the people affected. They may keep their affected hand in their pocket, behind their back or hold something to control the tremor, which may be more psychologically distressing than any physical limitation that it imposes. Over time, initial symptoms become worse. A mild tremor becomes more bothersome and more noticeable. Difficulties may develop with cutting food or handling utensils with the affected limb.
Slowness of movement
Slowness of movement (bradykinesia) becomes a significant problem and the most disabling symptom. Slowness may interfere with daily routines; getting dressed, shaving or showering may take much of the day. Mobility is impaired and difficulty develops in getting into or out of a chair or a car, or turning over in bed. Walking is slower and there is a stooped posture, with the head and shoulders hanging forward. The voice becomes soft and monotonous. A disturbance of balance may lead to falls. Handwriting becomes small (micrographia) and illegible. Automatic movements, such as arm swing when walking, are reduced.
Rigidity in Parkinson’s is a stiffness of the muscles. To test for rigidity, the examining doctor moves the relaxed body part slowly and gently and tests for any resistance to movement.
The ability to maintain posture and balance may be affected in people with Parkinson’s. This can lead to poor balance (postural instability) and unsteadiness when walking, turning or standing, or when performing actions such as rising from a chair or bending over. Any of these unsteady movements may lead to a fall, which is a major cause of injury in people with Parkinson’s.
There are many practical devices, such as handrails, walking sticks and walking frames, that can help with stability and can prevent falls. A physiotherapist will be able to identify the right walking device for each person.
Symptoms may originally be restricted to one limb, but will typically spread over time to the other limb on the same side. They eventually progress to the other side of the body. Generally this progression is gradual, but the rate of progression varies. As symptoms progress, it is important for people to talk with their physicians so that optimal treatment can be established. The goal of treatment is not to abolish symptoms, but rather to help the person manage them, function independently and make the appropriate adjustments to a chronic illness. The illness will not go away, but management of its symptoms can be successful in reducing disability.
People are aware of the progressive nature of the illness and this may become a source of much anxiety. It is not uncommon for them to over-monitor themselves and their symptoms, compare themselves to other people with Parkinson’s whom they may meet (length of diagnosis, level of symptoms, etc.) and avoid situations such as support groups, where they may see others who are worse off than they are. Concern about the progression of the disease and the ability to continue working is frequently voiced.