Scott-Pandorf Melissa M, Stergiou Nicholas, Johanning Jason M, Robinson Leon, Lynch Thomas G, Pipinos Iraklis I
University of Nebraska at Omaha, Omaha, Nebraska, USA.
J Vasc Surg. 2007 Sep;46(3):491-9. doi: 10.1016/j.jvs.2007.05.029.
Claudication is the most common manifestation of peripheral arterial disease (PAD), producing significant ambulatory compromise. The gait of claudicating patients has been evaluated using primarily temporal and spatial parameters. With the present study, we used advanced biomechanical measures to further delineate the ambulatory impairment of claudicating patients. We hypothesized that the claudicating legs of PAD patients have an altered kinetic gait pattern compared with normal legs from control subjects.
Ambulation kinetics (ground reaction forces) were evaluated in claudicating patients and compared with age-matched healthy controls. Forces were analyzed in the vertical, anterior-posterior, and medial-lateral directions. Time from heel touch-down to toe-off (stance time) and time spent in double-limb support were also evaluated.
The study recruited 14 PAD patients (age, 58 +/- 3.4 years; weight, 80.99 +/- 15.64 kg) with femoropopliteal occlusive disease (ankle-brachial index [ABI], 0.56 +/- 0.03) and five controls (age, 53 +/- 3.4 years; weight, 87.38 +/- 12.75 kg; ABI, >or=1.00). Vertical force curve evaluation demonstrated significant flattening in claudicating patients resulting in a lower and less fluctuant center of mass when ambulating. In the anterior-posterior direction, claudicating patients demonstrated significantly decreased propulsion forces. In the medial-lateral direction, they had significantly increased forces consistent with wider steps and an inability to swing their legs straight through. Claudicating patients demonstrated a greater stance time and time in double limb support compared with healthy controls. Most importantly, gait abnormalities were present before the onset of claudication, with gait worsening after the onset of claudication.
Claudicating patients demonstrate significant gait impairments that are present even before they experience any limb discomfort. These alterations may make them feel more stable and secure while attempting to minimize use of the affected limb. Advanced biomechanical analysis, using ambulation kinetics, permits objective and quantitative evaluation of the gaits of claudicating patients. Such evaluation may point to new rehabilitation strategies and provide objective measurement of functional outcomes after medical and surgical therapy.
间歇性跛行是外周动脉疾病（PAD）最常见的表现形式，会严重影响行走能力。既往主要通过时间和空间参数来评估间歇性跛行患者的步态。在本研究中，我们采用先进的生物力学测量方法进一步明确间歇性跛行患者的行走功能障碍。我们假设，与对照组正常受试者的腿部相比，PAD患者出现间歇性跛行的腿部其动态步态模式存在改变。
对间歇性跛行患者的行走动力学（地面反作用力）进行评估，并与年龄匹配的健康对照者进行比较。分析垂直、前后和内外侧方向的力。还评估了从足跟触地到足趾离地的时间（支撑时间）以及双腿支撑所花费的时间。
本研究纳入了14例患有股腘动脉闭塞性疾病（踝肱指数[ABI]为0.56±0.03）的PAD患者（年龄58±3.4岁；体重80.99±15.64 kg）以及5名对照者（年龄53±3.4岁；体重87.38±12.75 kg；ABI≥1.00）。垂直力曲线评估显示，间歇性跛行患者的曲线明显变平，导致行走时质心更低且波动更小。在前后方向上，间歇性跛行患者的推进力显著降低。在内外侧方向上，他们的力显著增加，这与步幅变宽以及无法将腿伸直摆动有关。与健康对照者相比，间歇性跛行患者的支撑时间和双腿支撑时间更长。最重要的是，步态异常在间歇性跛行发作之前就已出现，且在间歇性跛行发作后步态恶化。
间歇性跛行患者即使在未出现任何肢体不适之前就已存在明显的步态障碍。这些改变可能使他们在试图尽量减少患侧肢体使用时感觉更加稳定和安全。采用行走动力学的先进生物力学分析能够客观、定量地评估间歇性跛行患者的步态。这样的评估可能会指向新的康复策略，并为药物和手术治疗后的功能结局提供客观测量。
