Endoscopic surgical instrument having a retractable cutting blade and surgical procedure using same

Inventors

Mirza, Ather • Mirza, Romi

Assignees

A M Surgical Inc

Abstract

An endoscopic surgical instrument includes a main body assembly, and a cannula having a lumen and formed with a slot. An inner tube, which houses a spring-biased retractable cutting blade assembly having a cutting blade, is mounted on one end of the main body assembly and extends axially therefrom. The tube is receivable within the lumen of the cannula, and may be particularly oriented within the cannula lumen such that the cutting blade may be caused to project from both the tube and the cannula slot. The inner tube has a bore in which the distal end of an endoscope may be received. The instrument may be locked in one position to allow the endoscope to engage the blade assembly and cause the cutting blade to project from the cannula slot during a tissue cutting procedure, or may be locked in another position wherein the cutting blade remains retracted.

Core Innovation

The disclosed invention is an endoscopic surgical instrument that includes a main body assembly, a cannula mounted on the front end of the main body assembly, and an inner tube mounted at the front end such that the distal end of the inner tube is receivable by the lumen of the cannula. The cannula includes a tubular member with a lumen extending axially and an axially-extending slot formed on the tubular member that is in communication with the lumen. The inner tube includes a bore extending axially and a blade slot formed thereon, and the inner tube is positionable within the lumen so that the blade slot is selectively aligned with the axially-extending slot formed in the cannula.

A retractable cutting blade assembly is mounted in the bore of the inner tube in proximity to the distal end, with a cutting blade positioned to align with the blade slot on the inner tube so that the cutting blade selectively projects outward through the blade slot of the inner tube and through the axially-extending slot of the cannula, and selectively fully retracts into the bore of the inner tube. The main body assembly and the inner tube are configured to receive at least a distal viewing end portion of an endoscope or arthroscope such that the distal end is selectively engagable with the retractable cutting blade assembly.

The main body assembly is configurable between at least a first state and a second state. In the first state, the main body assembly prevents the distal end of the endoscope or arthroscope from engaging the retractable cutting blade assembly, thereby maintaining the cutting blade in a retracted position within the bore of the inner tube. In the second state, the main body assembly allows the distal end to engage the retractable blade assembly, thereby causing the cutting blade to project outward of the inner tube through the blade slot formed therein and outward of the tubular member of the cannula through the axially-extending slot formed therein. The disclosed structure further supports soft-tissue release surgery, including carpal tunnel syndrome and flexor retinaculum/transverse carpal ligament release.

The disclosed instrument is further described as including a transparent, slotted cannula and an inner tube carrying a spring-biased retractable cutting blade assembly, with selective locking of an endoscope/arthroscope distal tip in a “SCOPE” mode to prevent blade actuation and in a “BLADE” mode to engage the blade assembly so it projects through aligned slots. The distal end includes a viewing window for angled viewing, and the instrument includes a rotatable multi-position main body with a surgeon switch that controls blade engagement based on axial extension of the endoscope or arthroscope, using blade actuator structure including blade housings, an actuator pin in an arcuate slot, a pivot pin, compression springs, and endoscope-press compression for blade extension and retraction.

Claims Coverage

Independent claim clm-00001 provides three core inventive feature groups: slot alignment and retractable cutting blade arrangement between an inner tube and a cannula, configurable main body state control, and selective engagement of an endoscope or arthroscope distal end with the retractable cutting blade assembly.

The claimed coverage centers on an inner-tube blade slot selectively aligned to a cannula axially-extending slot, a retractable cutting blade assembly mounted in the inner-tube bore that projects through those aligned slots, and a configurable main body mechanism that, via selective engagement of the endoscope or arthroscope distal end, controls whether the cutting blade remains retracted or projects.

Stated Advantages

Documented Applications