Participants
Participation in the study was offered to 100 consecutive PD patients attending the Movement Disorders Clinic, Department of Neurology, University Hospital in Cracow. Inclusion criteria were: diagnosis of PD according to UK PD Society Brain Bank criteria [13] established at least 6 months prior to the study, 1.5–3.0 Hoehn and Yahr stage and unchanged pharmacological treatment for at least 3 months preceding the study. The subjects’ informed written consent for participation was obtained. The study was conducted in accordance with the Declaration of Helsinki. Exclusion criteria were: severe gait disability with inability to walk unassisted, neurological, vascular or systemic disorders that may have caused permanent or intermittent weakness or instability, severe hepatic or renal insufficiency, cancer, a history of orthopedic hip or knee surgery which led to gait difficulties, other chronic disorders of the musculoskeletal system leading to restricted mobility, as well as all other contraindications to exercise.
Measurements
The assessment of balance, gait, motor functions and trunk rotation in both rehabilitation and control groups was preceded by clinical evaluation by a neurologist with expertise on the subject of movement disorders, including a demographic and medical questionnaire and neurological examination. The severity of the disease was assessed using the Unified Parkinson’s Disease Rating Scale (UPDRS) part 3, the Hoehn and Yahr scale and the Schwab and England scale. Drug treatment was kept unchanged throughout the study.
Patients were randomly allocated into two groups: rehabilitation or control, using a random number computer generator. Patients were assessed three times at month intervals, during “on” state. Between the first and second assessments, the rehabilitation group participated in a 1-month rehabilitation program, consisting of 28 therapeutic sessions. Participants in the control group received only medication therapy. After the study was completed, two kinds of rehabilitation programs were offered to patients from the control group.
Balance was assessed with the Pastor test (shoulder tug) and tandem stance. Gait was assessed with a 10 m walk at preferred speed and 360° turn. Motor performance was assessed by means of the Physical Performance Test (PPT) and timed motor activities. The range of spinal rotation was measured in the lumbar and thoraco-lumbar spine with a tape measure. A digital stopwatch was used to time the motor tasks.
Balance tests
Tandem stance
The time of maintaining balance in tandem stance was measured for a maximum of 30 s [14, 15].
Pastor test
Postural reactions in response to external perturbation (shoulder tug) were scored using the 5-point scale. The higher the score, the worse the balance in response to external perturbation. One point means that a subject maintains upright without taking a step and 5 points are given when a subject falls without attempting to step [14, 17].
Gait assessment
Patients were asked to walk 10 m at a normal, preferred speed. Time and number of steps were measured, and the average step length was calculated [15, 16, 18].
The number of steps during the 360° turn was counted [16].
Physical performance
The nine-item PPT assesses physical functional capabilities. The following maneuvers simulating daily activities were assessed: writing a sentence, simulation of eating, rising up and putting a heavy book on a shelf, dressing and taking off a jacket, picking up a coin from the floor, turning 360°, gait test, climbing stairs, number of flights during climbing the stairs (maximum 4). Seven of the nine tasks were timed and the scores for time intervals of each task were given, from 0 if task was unable to be performed to 4 if it was performed at its possible best. During the 360° turn, stability and continuity of turning were assessed. The maximum score for the nine items is 36 points [19, 20].
To assess basic motor performance, the time of the following functional tasks was measured with a stopwatch: standing up from sitting, standing up from lying on the treatment table, sitting down from standing, lying down on the treatment table from standing, lying down on the treatment table from sitting, lying down on the exercise mat from standing, rolling from supine to side lying on the treatment table, rolling from supine to prone lying on the exercise mat and standing up from lying on the exercise mat [15, 16].
Spinal axial rotation
The range of trunk rotation was measured with a tape measure according to the Pavelka method [21]. The difference between starting and final position after maximum rotation of the trunk is the result.
The patient was seated on a chair with the feet fastened to chair legs for stability of the pelvis. The trunk rotation was measured in the lumbar (1) and thoraco-lumbar, (2) spine twice, to the right and left. The final result was an average of the two consecutive measurements.
-
1.
The range of rotation in the lumbar spine was determined by measuring the distance between the spinous process of the fifth lumbar vertebra and xiphoid process of the sternum and after maximum rotation. In healthy people after maximum movement, the distance increases by an average 6 cm.
-
2.
The range of rotation in the thoraco-lumbar spine was determined by measurement of the distance between the spinous process of the fifth lumbar vertebra and jugular incisure of the sternum and after maximum rotation. In healthy people after maximum movement, the distance increases by an average of 7 cm [21].
Rehabilitation program
The rehabilitation program lasted for 4 weeks and consisted of 28 therapy sessions. Each of them lasted 2 h with breaks, two times per day during the first 2 weeks (11 therapeutic sessions, one session took place on Saturday), and during two consecutive weeks: three times per week, one session per day. Intervention was conducted in the small groups consisting of 2–3 patients.
Treatment was focused on various exercises improving balance, postural stability, walking and performance of ADL, including changing position of the body. The rehabilitation program consists of: relaxation exercises, respiratory (breathing) exercises, range of motion and stretching exercises, exercises of trunk rotation in various body positions, mobility exercises and functional training, postural re-education, balance exercises, gait training, music and elements of dance, speech therapy and exercises of facial expression as well as education (Table 1). The number of repetitions depended on the individual capacity of each patient; however, in the beginning the number was small and gradually increased as the patients’ ability improved.
Table 1 Examples of selected exercises
All of the exercises were performed with sensory enhancement in the form of external sensory cues, such as verbal, auditory, visual, proprioceptive or tactile stimulation. To provide sensory reinforcement and help increase the patients’ awareness of movement, we used verbal commands, counting, clapping, music, metronome, mirrors and floor markings. Exercises were performed in various body positions. Patients practiced weight-shifting exercises on various surfaces and with different feet positions. For gait training, visual cues (white, transverse lines or wooden sticks were placed at individual step lengths) as well as auditory rhythmical cues were used. Gait patterns used for both distance walking and walking during functional activities were practiced. Varying conditions: obstacles, narrow passages and places determined for turning were used. “Stop and go” exercises, changes in direction and changes in movement patterns were stressed. Patients were trained to walk during simulation of everyday life events (for instance, opening and closing doors, avoiding, slalom between obstacles or overcoming obstacles). The “attentional strategy” with verbal cues was also used to facilitate walking. Patients practiced dance-based exercises and simple dances with the aim of improving balance, initiation of movement, changing direction, trunk rotation and coordination. These types of exercises had additional motivational and social benefits.
Data analysis
Descriptive statistics are shown as mean ± SD. The comparisons between the groups were carried out with the non-parametric Mann–Whitney test. The three consecutive assessments were compared to each other both in the rehabilitation and control groups. For this type of comparison we used Friedman’s non-parametric analysis of variance for dependent tests, and in the consecutive stage of analysis, multiple comparisons of the Duncan’s test. A p value <0.05 was considered statistically significant. The quantitative variables such as sex were compared with the χ
2 independence test.