Background: In the course of rheumatoid arthritis (RA), an important problem that affects the stability and symmetry of lower limb loading is the global motor impairment of the foot due to its planovalgus deformity, as well as the occurrence of numerous lesions in the foot joints. In ankylosing spondylitis (AS), there is eventually a permanent limitation of spinal mobility, which results in impaired lower limb loading and body balance. In systemic sclerosis (SSc), pain and joint contractures negatively affect the proper posture and stability of the body and the normal lower limb loading.
Material and methods:Tests of body balance, stability and symmetry of lower limb loading were performed on a computerised two-plate stabilometric platform. The testing consisted of two trials -the first performed with eyes open (open-eye test) and the second performed with eyes closed (closed-eye test). Results: There were a total of 50 AS patients, 68 RA patients and 53 SSc patients examined. There were no statistically significant differences between the study groups including the open-eye test and the closed-eye test. Each study group revealed statistically significant higher values for the total distance travelled by the patient's centre of pressure of the feet over the course of testing as assessed using the closed-eye test compared to the open-eye test. Discussion: The groups analysed in this paper represent three functionally distinct connective tissue diseases that are marked by involvement of different constituents of the motor system component. Systemic sclerosis (SSc) presents itself as a disease with a completely different movement pattern that is marked by a reduction in the amplitudes of the centre of pressure (CoP) in both the closed-eye test and the open-eye test. Conclusions: Postural and balance disorders are common in rheumatic diseases, and the pattern of movement disorders is disease-specific.