Wound Closure Device

Patent application number: GB1205715.4

The problem

There are many existing methods of wound closure. Sutures are very effective but unsuitable for use on thin or delicate skin, and are less suited to use in children who may be too frightened to comply with this form of treatment.

Staples are useful for rapid wound closure but are prone to causing scarring and tissue trauma, and are therefore only suitable where speed of closure trumps cosmesis (such as heavily bleeding scalp wounds).

Tissue adhesives offer rapid and atraumatic wound closure but have insufficient tensile strength for gaping wounds, and due to being water soluble are only suited to wounds that are not bleeding.

Wound closure strips are an often-used further option. These have the advantage of being inexpensive and very gentle to use. They also avoid 'perpendicular' scarring sometimes seen after closure with sutures or staples.

However, traditional wound closure strips can be cumbersome to use – they have a tendency to stick to themselves and fold over, to stick to the gloves often worn by the healthcare worker, and to detach from the skin if used to pull the wound closed. They also come in pre-set lengths that may be unsuitable for closing a particular wound, and sometimes the assistance of an extra person is needed to apply the strip, dab the wound dry and pull the wound together in one action.

The solution

The Mantra Medical Wound Closure Device builds on the strengths of wound closure strips while avoiding their pitfalls to provide an extremely elegant form of wound closure.

This device makes application of wound closure strips easier, faster and less wasteful than before while also providing a means of single-handedly drawing a wound closed, leaving the other hand free to dab the wound dry.

It also allows the length of wound closure strip to be customised to the wound rather than coming in 'standard' lengths, and is designed to be disposable in the most environmentally sound way possible.

Single use

The device will be single use and will contain a roll of wound closure material on a central spool. A control button on the device can be used to apply tension to the wound closure strip allowing a wound to be drawn closed with one hand. A simple forward tilt of the device presses the strip against a blade allowing the wound closure strip to be cut as desired. The blade is sheltered between two 'shoulders' that hold the skin away from the blade, avoiding the possibility of any inadvertent skin trauma.

Because the blade will require more costly disposal than the remainder of the device, it is designed to easily detach with its housing from the main body of the device after use. This allows the blade to be thrown into 'sharps waste', while the remaining majority of the device is suitable for general clinical waste.

Application

This device will be particularly useful for large and multi-directional wounds through thin skin – the most obvious and exciting application is in closure of pre-tibial wounds in the elderly.

Sutures and staples are absolutely contra-indicated in such wounds and glue would be ineffective due to wound tension and bleeding. Traditional wound closure strips are the normal method of closure, but their application to these wounds is often very time-consuming due to the size and complexity of the skin breaks often found. Our research suggests that this device will be seen as far preferable to traditional strips in closing these wounds.

Competition

Competing forms of wound closure include sutures, staples, tissue glue and traditional wound closure strips. However, as described they all suffer from a number of inherent drawbacks. A further problem, especially with staples and glue, is cost: a vial of tissue glue costs £6.25 and a single use tissue stapler around £11.

The Mantra Medical wound closure device provides a quick, easy and precise wound closure method that avoids the inherent problems of existing solutions and is less expensive than sutures, glue or staples.

Initial design on this device has been completed and it is a registered design in the EU. As a Class I device under the Medical Devices Directive it need not be submitted for formal compliance testing.

Wound Closure Method - Cost Comparison
Wound closing method Cost
Stapler £11.00
Tissue adhesive, single vial £6.50
Mantra Medical Wound Closure Device £4.50
Sutures £3.00
Wound closure strip x 10 £0.40

Market size

It seems reasonable to estimate conservatively that the average A&E department would see at least 30 'opportunities' per day for wound closure strip use. There are 538 A&E and minor injury units in the UK, meaning approximately 5.89 million 'opportunities' per year for the wound closure device to be used.

Therefore, even a 1% penetration of this market would provide a substantial positive return. With economies of scale and further materials research it is hoped that the device could be manufactured for £1 and marketed for £4.50, comparing very favourably with competing solutions.

Market research and feedback

This device is at the advanced concept stage and has been submitted to several focus groups consisting of staff nurses, healthcare assistants, A&E sisters and doctors of varying grade. As the people most likely to use the device in clinical practice their opinions are invaluable.

Feedback was extremely positive. Staff were particularly keen on the increased speed and flexibility of wound closure offered by the device. Most commented that they would “use it tomorrow” and all agreed that it would make closing of routine wounds more time and resource efficient.

While it certainly wouldn't be used on every wound (nor is it intended to be), the feedback groups suggest that it would have the potential to be used multiple times each day within the average A&E department.