ABSTRACT
Objectives:To investigate the effects of different plantarflexion resistance of an ankle foot orthosis (AFO) on the motion of the thorax and pelvis during the gait of stroke patients. Methods:From June, 2020 to January, 2021, 26 stroke inpatients in Beijing Bo'ai Hospital wore AFO with oil damper (OD) ankle hinge, and measured thorax and pelvis during stroke gait under three plantarflexion resistance (OD1, OD2.5, OD4) of the AFO with a three-dimensional motion capture system. The main parameters were pelvic (P) and thoracic (T) angles at the following time or phases: initial contact (IC), contralateral foot off (CFO), contralateral initial contact (CIC), foot off (FO); the change of thoracic angle in gait cycle (Tcyclex), the change of thoracic angle in stance phase (TSTx) and the change of thoracic angle in single stance phase (TSSx). Thoracic and pelvic motions were defined on three coordinate axes: forward/backward tilt (x), oblique (y) and rotation (z). Results:The loading response times were significant different among different plantarflexion resistance conditions (χ2 = 7.923, P = 0.019), as well as between OD2.5 and in OD4 (P = 0.017). PCFOx, PCFOz, PCICx and PFox; TCFOx, TCFOy, TCFOz and TFOx; relative angle of thorax to pelvis TPICx, TPCFOx and TPCICx; and TSSx were significant different among three resistance conditions (χ2 > 6.077, P < 0.05). Forward tilt of pelvis decreased in condition OD2.5 and increased in condition OD4 during each timing. When CFO, the thoracic forward/backward tilt angle was less in OD2.5 than in OD4 (P < 0.05), the thoracic rotation angle was less in OD1 than in OD4 (P < 0.05). Conclusion:Plantarflexion resistance has a significant effect on the motion of the thorax and pelvis in the gait of stroke patients. Under the middle magnitude of resistance, the pelvic and thoracic posture becomes more upright, the oblique angle is reduced, showing the improvement of the upright posture. On the contrary, the pelvic forward tilt and thoracic oblique are increased when resistance become low or high, compensation of rotational motion appeared in high resistance, posture getting worse.
ABSTRACT
Objective:To quantitatively evaluate the biomechanical properties and proprioception by comparing the range of motion (ROM), muscle strength, stiffness and proprioception of ankle joint in patients with ankle sprain, in order to provide therapeutic strategy for the patients with ankle sprain. Methods:From April to July, 2019, 21 patients with ankle sprain were included. The ROM and muscle strength of bilateral ankle joint were recorded, and the stiffness was evaluated by ankle joint training assistant system, at the end of dorsiflexion and plantarflexion, and plantarflexion 20°. The proprioception of ankle was quantitatively evaluated, including motion perception threshold (MPT) and passive position sense (PAPS). The ROM, muscle strength, joint stiffness, MPT and PAPS were compared, and the correlation among ROM, joint stiffness and proprioception were analyzed. Results:Compared with the unaffected side, the dorsiflexion and plantarflexion ROM decreased (|t| > 2.817, P < 0.05), the dorsiflexion and plantarflexion muscle strength decreased (|t| > 5.785, P < 0.01), the stiffness at the end of plantarflexion increased (t = 3.036, P = 0.007) in the affected side. However, there was no significant difference in stiffness at the end of dorsiflexion and dorsiflexion 20° between two sides (t < 0.874, P > 0.05), nor in MPT and PAPS (t < 0.695, P > 0.05). The plantarflexion ROM on the affected side was negatively correlated with the stiffness at the end of plantarflexion (r = -0.466, P < 0.05) and MPT (r = -0.613, P < 0.05), and MPT was positively correlated with the stiffness at the end of plantarflexion (r = 0.469, P < 0.05). Conclusion:The dorsiflexion and plantarflexion ROM and muscle strength decreased in the patients with ankle sprain, while the stiffness at the end of plantarflexion increased, which was related to proprioception. Quantitative measurements of ankle joint biomechanics and proprioception contributed to making ankle rehabilitation strategies. Rehabilitation after ankle sprain included training for ROM and muscle strength, and plantarflexion stretch to improve the plantarflexion stiffness, which may promote the recovery of proprioception and ankle function.