SLR - March 2010 - Jeremy L. Cook
Reference:
Myers, S. A., Johanning, J. M., Stergiou, N., Celis, R. I., Robinson, L., & Pipinos, I. I. (2009). Gait variability is altered in patients with peripheral arterial disease. Journal of Vascular Surgery, 49(4), 924-931.
Scientific Literature Reviews
Reviewed by: Jeremy L. Cook, DPM
Residency Program: Massachusetts General Hospital, Boston, MA
Podiatric Relevance:
With the increasing prevalence of metabolic syndromes and peripheral arterial disease (PAD) within the population (8-12 million in the U.S.), podiatric physicians need to be well versed in the signs and symptoms PAD, including its effect on gait.
Methods:
Thirty-six patients, 19 individuals with symptomatic PAD and 17 healthy controls were selected to participate in a treadmill test to evaluate flexion/extension and the kinematics of the ankle, knee, and hip joints while walking with the absence of pain or claudication. Two board-certified vascular surgeons performed a detailed history, physical examination, and gait assessment. Exclusiona criteria included ambulation-limiting cardiac, pulmonary, neuromuscular or musculoskeletal disease. Control participants had no subjective or objective gait dysfunction, and had an ankle-brachial index (ABI) ≥ 1.0. Patients were required to wear tight clothing, and reflective markers were placed at specific anatomical locations. The patients were able to familiarize themselves with the task of walking on the treadmill apparatus and continued at a self-selected speed for the collection of the data, which occurred over a period of at least 30 consecutive footfalls. Joint angles and kinematics were collected with the use of reflective markers and three-dimensional kinematics were acquired at 60 Hz using EVART software (Motion Analysis Corp, Santa Rosa, Calif). Stride-to-stride variability of joint flexion and extension were also calculated. Data analysis included standard deviation, and coefficient of variation. Independent t-tests were used to compare gait variability between groups. Variability was expressed using the largest Lyapunov exponent.
Results:
Patient and control group means for age, height, mass and BMI did not differ, indicating they were well matched. However, the clinical characteristics of the PAD and control groups were quite different. Symptomatic PAD patients had significantly higher largest Lyapunov exponent values and coefficient of variation values for all joints, and higher standard deviation values at the ankle and the hip (P < .05). These findings demonstrate that joint movement patterns of PAD patients during ambulation were farther apart in consecutive strides and indicate altered neuromuscular organization and increasing variability. The most variability was noted at the ankle joint.
Conclusions:
The gait of patients with a history claudication is abnormal even when walking in the absence of claudication symptoms. PAD leads to muscle and nerve damage in the lower extremity, perhaps interfering with the locomotor system and resulting in altered gait variability.