Parkinson's Disease: clinical features

CARDINAL FEATURES 

1:RIGIDITY -rigidity is nothing but increased resistance to movements by both , the agonist and antagonist muscle groups.It is one of the 4 cardinal features of PD. Patient complains of stiffness or heaviness of limbs.Rigidity is asymmetrical in the beginning , affecting only the proximal muscles.It may begin from shoulders and neck , gradually spreading to face and the extremities.It may be of either types-
cogwheel (jerky resistance on movement due to alternate contraction and relaxation of muscles)
or leadpipe (sustained resistance).
Rigidity increases as the patient tries to actively move or is under emotional stress.
Complications of rigidity are decreased range of motion, contractures  and postural deformity.It increases fatigue levels by increasing the resting energy-expenditure.Objective findings are reduced bed mobility and loss of reciprocal arm swing while walking.

 2:BRADYKINESIA-it means slow and difficult voluntary movements. The speed and amplitude of movements is reduced.All of this leads to increased dependence and poor quality of life of the patient.

 3:TREMORS-involuntary oscillations of body parts occuring at a frequency of 2-4Hz is called tremor.Presence of resting- tremor is an initial and a typical symptom of PD.This kind of tremor appears only at rest and disappears as the patient does an active movement.Tremor tends to be less severe if the patient is relaxed,and aggreviates on emotional stress and fatigue.Objectively it appears as a pill-rolling movement of fingers, supination-pronation of forearm,etc

4:POSTURAL INSTABILITY-affected posture and balance is observed in the later stages of PD.This happens due to rigidity , loss of ROM and weakness.Subjectively , the patient notices loss of balance when his/her attention is divided when he/she is performing a self initiated movement like walking.A flexed , stooped posture with bent hips and knees is commonly seen.Frequent falls are common due to loss of balance as the patient cannot quickly adapt to changing sensory conditions.Fear of falls, freezing and fatigue are yet other symptoms . Freezing refers to the rigidity that the patient experiences , which in turn leads to complete inability to move that particular part.for instance, legs 'freeze' while walking.


 OTHER CLINICAL FEATURES;

- GAIT: a typical short-shuffling or festinating gait is observed.This is because of the stooped posture and leads to a shorter stride length.It appears as if the patient is trying to avoid falling and is chasing his own centre of mass.Gait can be either anteropulsive(forward festinating) or retropulsive(backwadrs). Changing direction and turning is difficult so patient takes multiple small steps.Some patients stop only when there's an obstacle. Freezing episodes are way too common while walking.

- MOTOR PLANNING AND LEARNING:a typical 'start-hesitation' is seen.Carrying out complex movements is difficult.Micrographia or abnormally small and illegible handwriting is seen.Mask-like face is seen due to hypomimia or diminished expressiveness of face.Learning procedures is difficult but patient learns if the procedure is divided into steps which are commanded.

-SENSATIONS:sensory loss isn't seen but pain and parasthesias are common.Pain may also fluctuate according to the l-dopa administration.The pain increases in intensity while the patient is off the drug.In case of depression, the pain seems to increase too.Proprioceptive regulation may be affected making it difficult for the patient to judge the movements.Akathisia or an urge to move is commonly seen with restlessness.

 -SPEECH AND SWALLOWING: patient begins to sound monotonous and mutism may be seen in advanced cases.Dysphagia or difficulty in swallowing is common .

 -ANS:excessive sweating or seborrhea and excessive salivation or sialorrhea is seen.GI dysfunction,bladder dysfunction and sexual dysfunction is noted.

- CARDIOPULMONARY FUNCTION:orthostatic hypotension is common due to L-dopa. Respiratory impairments and airway obstruction are frequent.Kyphosis leads to reduced chest expansion and cardio pulmonary deconditioning.

- COGNITION AND BEHAVIOUR: depression , dysphoric mood and even dementia can be observed.Patients have troubles shifting attention.Slowness of thought and information processing is common.