Dr Paresh Doshi is Director of Neurosurgery at Jaslok Hospital and Research Centre, Mumbai
World Parkinson’s Day is celebrated on April 11 in the memory of Dr James Parkinson’s birthday. It was in 1817, in a landmark essay, Essay on the Shaking Palsy based on the observations of six patients, he described the cardinal signs of Parkinson’s disease, which included, posture, festination of gait and tremors. More than later 200 years the Parkinson’s disease remains a clinical diagnosis based on the physician’s observation of the symptoms of the patient.
Early signs and symptoms: The most common early symptom of Parkinson’s disease is tremors. The typical Parkinsonian tremors are called pill rolling tremor, it looks like as if the person is rolling pills. The most important characteristics of these tremors are that they are asymmetric, and usually start on one side and are suppressed during actions. For example, if the patient wants to drink a cup of tea the tremor will stop while drinking but as soon as he puts down the cup, and the hand starts to rest, the tremor will start. The other common presenting symptom is slowness. Many patients complain that their hand has become slow or the range of the hand movement has decreased. This leads them to seek opinion from Orthopaedic doctors where the diagnosis gets little delayed.
The third common symptom again associated with tremors and slowness is the change in handwriting. It is not surprising for many patients to be diagnosed with Parkinson’s disease following change in handwriting. The typical change in handwriting is that when they start to write, the letters are legible and of proper height but as the sentence progresses, they continue to decrease in the height, and they become illegible. In medical terminology we call this micrographia.
Some patients present with alteration in the gait. This is a more common feature in Parkinson Disease affecting patients above 60 years of age. There gait becomes slow and shuffling. Many times, this gets attributed to old age and hence there is a delay in the diagnosis.
Once again, the clue here is asymmetry, one leg becomes slower than the other. It looks like the patient has developed a mild paralysis and is dragging his feet. Another form of gait difficulty is freezing. Where the legs stick to the ground and it is difficult for patient to move forward. This is more pronounced when the patient walks through narrow corridors or in a crowded space. Occasionally if the gait disturbances is not detected early and diagnosed correctly it leads to falls and many patients present with falls, however, falls are not the first symptoms of Parkinson disease and if patient is suffering from falls than either he is an advanced Parkinson’s disease patient or is suffering from some other disorders.
The third symptom that James Parkinson’s described was stooped posture. Usually, this is also attributed to old age, if it occurs in elderly. The change in the posture comes little later. Some of the subtle symptoms of Parkinson disease that can get unnoticed are unexplained constipation, sleep disorders, lack of smell, mask like face and speech disturbances. Many of these appear much before even the tremor begins.
Parkinson’s is more commonly seen in elderly patients above 60 years of age. However, a small percentage of patients present below the age of 40 years. These patients are known as young onset Parkinson’s disease. A very small percentage of patients can get this disease below the age of 20 years and this is called Juvenile Parkinson’s disease.
The diagnosis essentially still remains clinical. When there is a doubt about the diagnosis, specialised investigations like MRI or SPECT scans are performed to exclude other pathologies.