Quantitative gait analysis for laser cue in Parkinson's disease patients with freezing of gait.

Background: The aim of this study was to investigate the gait spatiotemporal, kinematic, and kinetic changes of Parkinson's disease (PD) patient with freezing of gait (FOG) under the laser cue (LC). Such an approach may provide greater insight into the effects of LC on gait. Methods: Thirty-four PD with FOG (PD + FOG) and 32 healthy controls (HC) were tested in gait laboratory. Patients were tested at their usual self-selected speed in no laser cue (NC) first and then under LC condition. Sagittal plane kinematic and kinetic parameters of the lower-limb joints (hip, knee, and ankle joints) as well as spatiotemporal parameters (velocity, cadence, stride length, single and double support time), were measured. Spatiotemporal parameters and kinematic were submitted to one-way analysis of variance (ANOVA) to explore difference among NC, LC, and HC. Covariance analysis was used to compare kinetic parameters. Results: For PD + FOG, spatiotemporal parameters (stride length, velocity, and cadence) were significantly improved in LC (1.06 +/- 0.18, 1.01 +/- 0.19, 120 +/- 13.26, respectively) compared with NC (0.93 +/- 0.20, 0.87 +/- 0.17, 131 +/- 14.75) (P=0.027, 0.045, 0.035, respectively), and close to HC (1.1 +/- 0.12, 1.12 +/- 0.13, 116 +/- 9.37) (P=0.594, 0.276, 0.084, respectively). In kinematics, LC could significantly ameliorate the amplitude of maximal dorsiflexion in ankle (35.1 +/- 3.8), extension in stance in knee (16.8 +/- 4.3) and hip (4.43 +/- 5.1), as well as the range of motion (ROM) in ankle (33.15 +/- 6.1) and hip joints (38.6 +/- 3.3). In kinetics, LC also markedly improved power generation in ankle (2.03 +/- 1.52) and hip joints (1.08 +/- 0.48) and power absorption in pre-swing phase in knee joint (-1.68 +/- 0.29) compared with NC (1.37 +/- 1.13, 0.899 +/- 0.43, -1.31 +/- 0.27, respectively). Conclusions: LC significantly improves gait performance in spatiotemporal parameters as well as kinematics and kinetics performance in ankle and hip joints. LC may be promising when applied as an optional technique in the rehabilitation training in PD + FOG.