Patent Application
20250049605
This invention belongs to a class of devices that treat injuries of the distal joint of the digit wherein there is loss of extension of the distal interphalangeal joint (DIP) commonly referred to as a mallet injury. These devices passively maintain the DIP joint in extension during healing of the terminal tendon in a finger or extensor pollicis longus tendon in a thumb.
Previously described devices in this class decrease tactile function of the digit while being worn by virtue of their designs which wrap around the tip of the digit (Barnes 2009, Barnes 2016), or cover a portion of the skin of the finger pad with a rigid or dense material (Kleinfield 1949, Link 1987, Link 1993, Stuart 2014, Wong 2017).
The current invention is novel by overcoming the loss of tactile function of the skin of the finger pad created by these prior designs. The current invention does so by leaving the tip of the digit uncovered by any material of the device and also by using a thin flexible material as the element of the splint which contacts the finger pad.
Prior designs are limited by the manner in which they cross the DIP joint without an apex volarly angled element at the level of the joint (Hawley 1901, Kleinfeld 1949, Link 1987, Stuart 2014). Such straight designs allow the DIP joint to partially flex if the splint migrates distally while being worn. This is a common problem when perspiration reduces adhesion of the tape or strap used to secure the splint to the middle phalanx. Straight designs or designs with a gentle bow rather than an angle placed at the level of the joint also allow the DIP joint to flex if the splint does not perfectly fit the size of the digit. The additional room within the splint or distal migration of the splint compromises the intended purpose of maintaining full extension or hyperextension of the DIP joint. Additionally prior designs that purposely place the DIP joint in flexion rather than extension are not intended for treatment of mallet injuries (Chandler 1962)
The current invention overcomes prior straight designs by incorporating an apex volar angle to the splint as it crosses the level of the DIP joint. The fixed volar angle of the current invention provides a means for the wearer to achieve a reproducible hyperextension angle across the joint and does not require manipulation of springs or screws as described in prior designs to achieve a desired extension angle.
In one aspect, the embodiments for the inventive concepts disclosed herein are directed to:
A device formed from a thin, rigid material curved to fit the dorsal soft-tissue contour of the middle phalanx of a digit with one or more apex volarly angled distal projections which arise at the level of the distal interphalangeal joint and with a thin sling of material secured to the distal projection(s) by which the volar pad of the distal phalanx is supported in order to provide hyperextension of the distal joint of the digit while maintaining tactile function of the pad of the digit.
Implementations of the inventive concepts disclosed herein may be better understood when consideration is given to the following detailed description thereof. Such description makes reference to the included drawings, which are not necessarily to scale, and in which some features may be exaggerated and some features may be omitted or may be represented schematically in the interest of clarity. Like reference numerals in the drawings may represent and refer to the same or similar element, feature, or function. In the drawings:
Before describing in detail embodiments of the inventive concepts disclosed herein, it should be observed that the inventive concepts disclosed herein include but are not limited to a novel structural combination of components and circuits, and not to the particular detailed configurations thereof. Accordingly, the structure, methods, functions, control and arrangement of components and circuits have, for the most part, been illustrated in the drawings by readily understandable block representations and schematic diagrams, in order not to obscure the disclosure with structural details which will be readily apparent to those skilled in the art, having the benefit of the description herein. Further, the inventive concepts disclosed herein are not limited to the particular embodiments depicted in the schematic diagrams, but should be construed in accordance with the language in the claims.
The device may be used for loss of extensor tendon function of the distal joint of a digit whereby loss of normal motion compromises function. The essential functions of the various embodiments of the device are to provide an extension rotational force centered at the level of the distal interphalangeal joint.
The various elements of the device function through the construction of a thin rigid proximal component contoured to the middle phalanx and one or more apex volar angulated distal extensions to which a thin flexible material is secured which provides volar support to the pad of the digit.
By way of example and referring to
CLASS 602/22, SURGERY: SPLINT, BRACE, OR BANDAGE Subject matter comprising an appliance which is specially adapted to be applied to a person”s arm to treat a bone disorder of the phalanges or the muscles associated therewith so that a more normal orientation of the body components is achieved.
