Engineering investigation of the Kensey dynamic angioplasty catheter.

This article describes an in vitro experimental study which was designed to gain a better understanding of the mechanism by which the Kensey catheter mediates atherosclerotic tissue. The major goals of the study were to observe the generation of debris particles during revascularization and to elucidate the fluid dynamic effects associated with particle motions at and around the tip of the catheter. To investigate these phenomena, in vitro actual size and large scale model experiments were conducted. The results of these experiments provide a reference for the significance of the clinical performance of the Kensey catheter.

Recanalization of total arterial occlusions with the Kensey dynamic angioplasty catheter.

The Kensey dynamic angioplasty catheter is a new device for recanalization of peripheral arterial occlusions. Twelve patients with segmental occlusions who were not considered candidates for conventional bypass surgery because of cardiovascular risk factors were studied. Four of the patients were treated in the operating room. Two had excellent primary results in limb salvage situations, and recanalization of an occluded femoropopliteal bypass graft was successful in another. Bilateral iliac recanalizations in the fourth patient were locally successful but did not prevent the patient's death from advanced ischemic disease. Eight patients were treated percutaneously. Initial recanalization was successful in seven. Four had early reocclusions and required amputation below the knee. One suffered distal embolization after recanalization of a 6-cm popliteal segment and underwent above-the-knee amputation. Long-term follow-up (7-18 months) in the other three patients with successful primary recanalizations has confirmed patency of the recanalized segments.

Leg motion analysis during gait by multiaxial accelerometry: theoretical foundations and preliminary validations.

A theoretical formulation for studying limb motions and joint kinetics by multiaxial accelerometry is developed. The technique is designed to study the swing phase of human gait, modeling the lower leg as a rigid body. Major advantages of the approach are that acceleration information needed for the calculation of forces and moments is generated directly, and that the method automatically generates its own initial conditions. Results of validation experiments using both artificial and experimental data demonstrate that the method is theoretically valid, but that it taxes available instrumentation and requires further development before it can be applied in a clinical setting.