Methods and devices for soft tissue dissection

Inventors

Moody, Ryan • Crenshaw, Hugh C. • Espenhahn, Eric T. • Pell, Charles A.

Assignees

Physcient Inc

Abstract

Methods and devices for blunt dissection include a drive mechanism comprising an elongate rotary drive train having a first proximal end connected to a mounting base for attaching to a handle or a surgical robot and a second distal end. The drive mechanism comprises a differential dissecting member (DDM) configured to be rotatably attached to the second distal end. The drive mechanism further comprises a mechanism configured to mechanically rotate the DDM about a substantially transverse axis of member rotational oscillation, thereby causing at least one tissue engaging surface to move in at least one direction against complex tissue and selectively engage the complex tissue such that when the DDM is pressed into the complex tissue, the at least one tissue engaging surface moves across the complex tissue and disrupts at least one soft tissue in the complex tissue, but does not disrupt firm tissue in the complex tissue.

Core Innovation

The invention relates to a differential dissecting member for differentially dissecting complex tissue. The differential dissecting member includes a body having a longitudinal axis with a distal end configured to engage tissue and a proximal end directed toward a drive mechanism, where the proximal end operatively engages an axle associated with the body.

A looped oscillating drive cable is operatively associated with the drive mechanism and affixes the body to the drive mechanism via a circuitous path. The circuitous path comprises at least one topologically constrained tortuous loop through the body, and the looped oscillating drive cable is captured in at least one passage through which the looped oscillating drive cable passes.

Proximal movement of one end of the looped oscillating drive cable and distal movement of another end produces rotation of the body and drives the body to high speed oscillations. The disclosed arrangements also include topologically constrained passages such as fenestrations, cable retention in a trough with a cleat, proximally tensioned cable holding the body on the axle, and a wedge-shaped body geometry with a narrower distal end and wider proximal end.

The drive architecture is described as a rotary drive train with a motion filter that generates planar oscillation of the tissue-engaging surface. The disclosed drive train can include an elongate rotary drive train and a differential dissecting member rotation about a substantially transverse axis, and can be configured as a steerable differential dissecting assembly.

Claims Coverage

The independent claim coverage is provided for one independent claim, with main inventive features including an axle-engaged differential dissecting member driven by a looped oscillating drive cable via a topologically constrained tortuous loop through the body to produce rotation and high speed oscillations. Dependent claim features refine topological constraints, cable retention, and additional operational parameters such as frequency range and body geometry.

The claim set centers on an axle-engaged differential dissecting member driven by a looped oscillating drive cable routed through a circuitous path having a topologically constrained tortuous loop through the body and captured in passages. Proximal and distal cable movement produces rotation and drives high speed oscillations, with dependent claim refinements that specify fenestration-based topological constraints, trough and cleat cable retention behavior, proximally tensioned cable holding of axle engagement, a defined 10 Hz to 1 kHz frequency range, and wedge-shaped body geometry.

Stated Advantages

Documented Applications