Primary and secondary deficits determinants for the balance disorders in Parkinson Disease.

The postural instability is one of the clinical signals that mostly cause loss of physical capability in individuals with Parkinson Disease (PD), however its origin still remains unknown. So, we investigated whether primary factors related to the disease like rigidity, bradykinesia and bent posture would compromise the range movement (ROM) in the lower limbs that could secondly prejudice the postural control furthermore. 12 subjects with PD (Hoehn e Yard 1-3) and 15 healthy with the same age and sex subjects as the control group were assessed. The subjects had their ROM of hips and ankles measured using goniometry and then, they were submitted to the Postural Stress Test ? PST (Wolfson e col., 1986), in witch there are extern disturbances proportional of the body weight, at the shoulders and waist. Then, it was verified the correlation between these data and some scores of characteristic postural control of PD from the Unified Parkinson Disease Rating Scale (UPDRS): the total score, the motor condition score (part C), an isolated scores like rigidity (question 22), posture (question 28) and bradykenesia/hypokinesia (question 31). It was verified that the PD subjects have significant compromised ankle and hip ROM when compared with the healthy subjects (dorsiflexion, p=0,044; plantiflexion, p<0,001; hip flexion, p=0,035, hip extension, p<0,001), besides the dorsiflexion and hip extension were directly correlated to the grade of compromise of all the data obtained in the UPDRS, except the posture. In relation to postural control, only the results of the posterior disturbance in shoulders at the PST were statistically different from the control group, being these data also correlated to the UPDRS scores (p<0,05). There were also a positive correlation trend between the ROM compromising in the inferior limbs and the postural misbalance (p=0,07). The present study showed that there are real ROM reductions in the lower limbs as secondary deficits of the PD, and identified some factors like bradikinesia, rigidity and motor and general compromising grade that are determinant for this muscular-articular deficit and for the postural instability observed in people with PD. We believe that we could find a significant correlation between these ROM deficits and the balance disorder characteristic of these patients increasing the number of subjects assessed. Our results allow a better comprehension of the origin of postural instability in PD people, what results in bigger possibilities of physical therapy intervention.