Parkinson's disease is a neurodegenerative disease defined by James Parkinson in 1817, resulting from the progressive loss of dopaminergic neurons in the basal ganglion and substantia nigra. The four main motor signs of the disease are resting tremor, bradykinesia, rigidity and postural instability. In addition, postural disorders, motor freezing, gait disturbances, decreased arm swing and axial rotation loss accompany the disease. There is an important relationship between axial rotation and turning, which is one of many activities in daily life. Turning is a complex action that involves head and trunk rotation in the transverse plane. En bloc turning occurs with the decrease of inter-segment coordination in Parkinson's patients with loss of axial rotation, which refers to the almost simultaneous rotation of the head, trunk and pelvis. This problem affects a large percentage of people with Parkinson's disease, hinders daily living activities, is associated with falls, and has a significant impact on quality of life. Losses in axial rotation also can affect properties of gait such as speed and stride length.

Physiotherapy is effective in improving gait, balance and functional activities in Parkinson's patients. Classical physiotherapy methods such as stretching, strengthening and posture exercises, balance, coordination and gait training, and different methods such as motor imagery, sensory stimuli and neurophysiological approaches can be used in the treatment of Parkinson's patients. Although there are applications that can increase axial rotation in physiotherapy programs, all programs may be able to focus adequately on the treatment of this symptom. In addition, according to the literature, the effects of all physiotherapy approaches emerge as a result of long-term training.

Mobilization techniques are applications that are included in physiotherapy programs and have a wide area of use. It is divided into three subtitles according to its severity and degree: Grade A (mobilization), grade B (mobilization) and grade C (manipulation). Grade A (mobilization) is active, active-assisted or passive mobilization in the spinal joints within the painless range of motion. It is generally applied in the middle range in spinal joints. It is especially preferred in the treatment of acute, irritable spinal lesions. Grade B (mobilization) refers to mobilization in the form of continuous stretching at the end of the range of motion in the spinal joints. Grade C (manipulation) is a minimal amplitude high velocity passive pushing motion performed at the end of the joint range of motion.

Considering the effects of mobilization on muscle activation and balance, grade A and grade B mobilization applications are likely to increase the mobility of this area when applied on the lumbosacral region. Therefore, these practices can affect balance, gait and functional activities by regulating muscle tone (rigidity) and muscle activation and reducing axial symptoms in Parkinson's patients. Based on this information, the aim of our study is to investigate the acute effect of lumbosacral mobilization on balance, gait and functional activities in patients with Parkinson's disease.