Patients tend to slump backwards while sitting and often slide sideways, with their head falling forward. Postural adjustment through weight shifting is usually difficult since weight is placed far back in the chair. This also leads to problems in getting from sitting to standing. Once walking is initiated it is difficult to shift weight properly a so they walk with short shuffling steps and a wide base. Patients may also experience freezing , especially in narrow passageways or doors.
Rigidity occurs due to an increase in tonic stretch reflexes.
It results in a high resistance to passive movements. It may be asymmetrical or unilateral and occasionally effects only a group of muscles. This symptom increases in cold environments and with stress. Posture is affected due to an increase in rigidity of one s back extensors. Finally, sensation is not usually effected, however patients usually experience pain, stiffness and aching of muscles and joints.