背景與目的：步態協調異常是巴金森氏症患者行走控制問題之一，且此問題在具凍凝步態的巴金森氏症患者更甚。過去少有研究探討行走訓練對步態協調改善情況，且由於步態協調會受上肢動作影響，因此動作—行走與認知—行走任務下的步態協調表現應有不同。本研究目的為探討具凍凝步態之巴金森氏症患者在動作—行走與認知—行走任務下之步態表現差異，以及經雙重作業行走訓練後，兩種任務下步態進步差異；步態將著重於協調相位指數(phase coordination index, PCI)之變化，該數值愈低代表步態協調愈佳。方法：27位具凍凝步態之巴金森氏症患者進行6週之雙重作業行走訓練。訓練前後，分別於有、無藥效情況下進行動作—行走與認知—行走任務測試，測量參數為行走速度、步幅、步頻、步幅變異數與PCI。結果：有藥效情況下，經訓練後可增加動作—行走與認知—行走任務下的行走速度、步幅與步頻，並降低步幅變異數與PCI，但各參數於動作—行走與認知—行走任務下並無顯著差異。無藥效情況下，於訓練前，動作—行走任務有較大的PCI；且經訓練後，僅有動作—行走任務可顯著降低PCI。其餘步態參數於動作—行走與認知—行走任務下無顯著差異。結論：具凍凝步態的巴金森氏症患者執行動作—行走任務，較認知—行走任務，對步態協調干擾為多，而經過雙重作業行走訓練可改善有、無藥效下動作—行走任務的步態協調。臨床意義：巴金森氏症患者在藥效較差時，執行動作—行走任務時的步態協調問題需更被重視，以降低患者跌倒機率。

Background and purpose: Impaired gait coordination is common in patients with Parkinson’s disease (PD), especially for PD with freezing of gait (FOG). However, only few studies focused on gait coordination in walking training. In addition, because gait coordination was affected by upper limb movement, the gait coordination of dual-task walking with a concurrent motor or cognitive task should be different. Therefore, the aims of the present study were to compare the effect of dual-task walking training on gait coordination in PD with FOG as well as the difference of gait coordination on these 2 types of dual-task walking (motor vs. cognitive). Gait coordination was assessed by phase coordination index (PCI). The lower value of PCI indicates a better gait coordination. Methods: 27 patients with PD and FOG received 6-week dual-task walking training with 1-hour per session and 2 sessions per week. The participants were evaluated under the on-medication and off-medication states before and after the training. Gait velocity, step length, cadence, step length variability and PCI were measured. Results: Under on-medication state, increased walking velocity, cadence and step length, and decreased step length variability and PCI were observed after training. Under off-medication state, PCI was greater in the motor-walking task than that in the cognitive-walking task before gait training. In addition, the value of PCI reduced after training only in the motor-walking task. Except for PCI under the off-medication-state, there was no significant difference on any gait parameter between the motor-walking and cognitive-walking tasks. Conclusions: For individuals with PD and FOG, Gait coordination was affected more by a motor-walking task than a cognitive-walking task. Also, gait coordination on motor-walking under both on-medication and off-medication states can be improved by dual-task walking training. Clinical Relevance: The issue of gait coordination in patients with PD and FOG should be emphasized, especially in dual-task walking with concurrent motor task during wearing-off period, in order to decrease fall risk.