External fixator for distal radius fracture

Inventors

Hajianpour, Mohammed A.

Assignees

Nutek Orthopaedics Inc

Abstract

An external fixator for a fractured distal radius including a first plurality of vertical passages for pins extending downward from a first pin mounting block into one or more bone fragments and one or more frame element apertures extending from an elongated frame element for pins extending downward from the device into the shaft of the radius. In addition, the elongated frame element includes a sliding pin slot with a sliding structure allowing a single pin to be moved to provide extension between the fragments and the shaft. A sliding internal plate including holes aligned with the first plurality of vertical passages is moved by a pair of setscrews to clamp the pins extending through the first plurality of vertical passages. The device also includes a second pin mounting block that extends downward parallel to the pins extending from first pin mounting block to hold pins directed laterally into the fragment(s).

Core Innovation

The invention relates to an apparatus for external fixation of bone fragments for a distal radius fracture. The apparatus includes a fixator body with a first pin mounting block at one end that includes a plurality of vertical parallel passages providing positions for vertical fragment pins, and an elongated frame element at an opposite end that includes elongated frame element apertures providing positions for mounting pins.

The apparatus provides vertical fragment pin positioning by mounting vertical fragment pins in the first pin mounting block and using a sliding plate mounted to slide along the fixator body. The sliding plate includes holes aligned with the vertical parallel passages, and a plate driving mechanism movable in an engagement direction slides the sliding plate along the fixator body and simultaneously clamps the vertical fragment pins.

The apparatus further includes a second pin mounting block that is slidably mounted orthogonally on one side of the fixator body, extends in a direction parallel to the first pin mounting block, and is moveable along an edge of the fixator body. The second pin mounting block contains one or more vertically oriented elongated slots, each containing a slidably mounted pin holding member comprising a spherical pin holder with a pin mounting hole for a lateral fragment pin, at least one deformable portion, and a spherical pin holder clamping mechanism that releasably fastens together and deflects the deformable portion to hold the lateral pin in place.

An elongated frame element further supports a sliding pin and a sliding pin slot for setting extension between fracture fragments and the radius shaft, with the sliding pin releasably clamped in place. The apparatus is described as allowing immediate post operative wrist and finger function and as providing improved stability of the distal radius fracture fixation, and the use of materials enabling X-ray imaging through the fixator is also described.

Claims Coverage

The document contains one independent claim. It covers an external bone-fixation apparatus combining a fixator body with vertically positioned fragment pins clamped by a sliding plate driven along the body, and an orthogonally slidable second pin mounting block with vertically oriented elongated slots using spherical pin holders and a clamping mechanism to hold lateral fragment pins, with a sliding pin for extension setting.

Overall, the claim coverage centers on a combination of a sliding plate that simultaneously clamps vertical fragment pins using aligned holes and vertical passages, a slidable second pin mounting block that uses vertically oriented elongated slots with spherical pin holders and a deformable-piece clamping mechanism to hold laterally oriented fragment pins, and a sliding pin for extension setting.

Stated Advantages

Documented Applications