WO2011015813A1

WO2011015813A1 - Active loader

Info

Publication number: WO2011015813A1
Application number: PCT/GB2010/001466
Authority: WO
Inventors: Mark Howard
Original assignee: Smith and Nephew PLC
Current assignee: Smith and Nephew PLC
Priority date: 2009-08-03
Filing date: 2010-08-03
Publication date: 2011-02-10
Anticipated expiration: 2012-02-03
Also published as: GB0913507D0

Abstract

The invention relates to apparatus and methods for use in the active loading of a three-dimensional scaffold with a fluid.

Description

ACTIVE LOADER

CROSS- REFERENCE TO RELATED APPLICATIONS

This application claims priority to UK provisional application No. 0913507.0 entitled "Active Loader" which is herein incorporated in its entirety.

FIELD OF THE INVENTION

BACKGROUND TO THE INVENTION

Surgeons involved in the repair of cartilage focal defects are looking for new methods to improve repair. The use of biological actives, such as growth factors, has been shown in the literature to facilitate repair of these defects. However, creating a stable scaffold combined with these factors is difficult and has yet to be solved. The alternative option is for the surgeon to load the scaffold during surgery themselves. Surgeons are left frustrated as they can easily access the biological actives from the relevant suppliers however as yet there is no easy method to load these scaffolds in surgery. Passive loading is inefficient. Surgeons often resort to using expensive centrifuges which are difficult to use and cannot be used within the surgical field.

The proposed invention will empower surgeons with the means to impregnate scaffolds used for focal defect repair with any biological active(s) of their choice quickly and easily during the surgery. The use of the device will be quick and easy to use and the rate and degree of permeation of the scaffold can readily assessed, hence ultimately providing surgeons with the confidence that they are providing a better quality of repair. The invention is able to directly load biological actives onto a three- dimensional scaffold in a quick and reproducible manner whilst maintaining sterility as there is minimal intervention from the surgeon. Scaffolds are used routinely in cartilage repair however the ability to easily combine a scaffold with any growth factor/active or cellular component during surgery is unique.

SUMMARY OF THE INVENTION

According to an aspect of the invention there is provided an apparatus for actively loading a fluid onto a 3-dimensional scaffold, the apparatus comprising;

(a) a chamber for receiving the scaffold, wherein an outer wall of the chamber is provided with an aperture through which the scaffold is insertable into and removable from the chamber,

(b) a fluid inlet associated with the chamber, the inlet being located such that when the fluid is introduced into the chamber it pools and forms a reservoir at a surface of the scaffold,

(c) an actuating means associated with the chamber, upon activation of which the fluid is conveyed from the reservoir through the scaffold. According to an aspect of the invention there is provided a method of actively loading a fluid onto a 3-dimensional scaffold, the method comprising the steps of;

(a) providing apparatus according to the first aspect of the invention,

(b) inserting the scaffold into the chamber,

(c) introducing the fluid through the fluid inlet,

(d) activating the actuating element to convey the fluid through the scaffold. According to a further aspect of the invention there is provided a kit of parts comprising a chamber according to the first aspect of the invention and a scaffold. In embodiments of the invention the kit further comprises a fluid detection means for association with the chamber or the scaffold.

According to a further aspect of the invention there is provided an apparatus, method or kit of parts as substantially herein described with reference to the accompanying Figures and Examples.

The chamber can be of any geometrical shape which is suitable for receiving a scaffold. The aperture through which the scaffold can be inserted or removed can be formed by the removal of a side wall of the chamber and a removable lid is associated with this aperture.

A fluid permeable membrane can be associated with the scaffold and it is upon this membrane that the fluid pools to form the fluid reservoir: Suitable membranes would be known to the skilled man, and include in particular membranes made of hydrophilic materials.

In embodiments of the invention the actuating means produces a negative pressure which causes the fluid to be drawn through the scaffold. In embodiments of the invention the actuating means produces a vacuum which pulls or draws the fluid through the scaffold. In one embodiment the vacuum is induced by an in-built resistance which when released would induce a reduction in pressure across the scaffold, causing the fluid to travel the length of the scaffold.

In alternative embodiments of the invention the actuating means produces a positive pressure which pushes or forces the fluid through the scaffold.

In embodiments of the invention the fluid is drawn vertically through the scaffold. In such embodiments the fluid reservoir is advantageously in contact with the complete surface area of the upper or lower surface of the scaffold, such that fluid is drawn vertically through the entire scaffold, thereby ensuring a homogeneous penetration of the scaffold with the fluid.

In embodiments of the invention the fluid is drawn horizontally across the scaffold. In such embodiments the fluid reservoir is advantageously in contact with the complete surface area of a side wall of the scaffold, such that fluid is drawn horizontally throughout the entire scaffold, thereby ensuring a homogeneous penetration of the scaffold with the fluid. In embodiments of the invention the apparatus further comprises a fluid detection means which is capable of both detecting and indicating the presence of a fluid. This can advantageously be used to indicate the level of penetration of the fluid through the scaffold. A suitable indicator is a metal salt which provides a visible color change upon conversion from a dehydrated to a hydrated state.

In embodiments of the invention the fluid detection means is associated with or is capable of being associated with the chamber and/or with the scaffold. Advantageously the fluid detection means is located on a visible part of the chamber or the scaffold when in use.

Advantageously at least a part of the chamber is transparent such that the fluid detection means can be visualised with the scaffold in situ. For example, a transparent window can be provided in the wall of the chamber such that the fluid detection means can be visualised through the window. Alternatively, the chamber can be made of a transparent material.

For example, the fluid detection means may be located or is locatable on an inner wall of the chamber, such that the detection means is in contact with a part of the scaffold when the scaffold is retained within the chamber.

Alternatively, the fluid detection means may be located or is locatable on the scaffold, for example on an outer surface of the scaffold. In embodiments of the invention the fluid detection means is removably associated with the chamber and/or with the scaffold, for example the fluid detection means may be adhered to a surface of the chamber or the scaffold by means of a suitable adhesive.

If the fluid detection means is associated with the scaffold then the means may be removable from the scaffold prior to use.

The fluid detection means must be biocompatible, for example, not toxic.

In embodiments of the invention in which the fluid penetrates the scaffold in a vertical direction, a fluid detection means can be located continuously or discontinuously along a vertical surface of the scaffold thereby enabling the vertical progress of the fluid through the scaffold to be monitored.

In embodiments of the invention in which the fluid penetrates the scaffold in a horizontal direction, a fluid detection means can be located continuously or discontinuously along a horizontal surface of the scaffold thereby enabling the horizontal progress of the fluid through the scaffold to be monitored. In alternative embodiments of the invention in which the fluid penetrates the scaffold in a vertical direction or horizontal direction, a fluid detection means can be located on or adjacent to the furthest region of the scaffold to which the fluid should penetrate, in order to indicate that the fluid has reached this point.

It is also envisaged that the apparatus may include a mechanism which facilitates the removal of the scaffold from the chamber. Such a mechanism may include a coil located within the chamber and into which the scaffold is retained. The application of a force to the coil causes the release of the scaffold. In a specific embodiment of the invention for use with a TRUFIT™ osteochondral plug (Smith & Nephew, Inc), the delivery device which is provided for use with the osteochondal plug can be used to depress the coil, release the plug and also capture the plug within the delivery device for delivery to the implantation site. In embodiments of the invention the scaffold is a medical implant, for example an orthopaedic implant such as a cartilage implant or a bone implant. In a specific embodiment of the invention the implant is the TRUFIT™ (Smith & Nephew, Inc).

In embodiments of the invention the fluid is a biological fluid or derivatives thereof, for example blood, serum or plasma.

In embodiments of the invention the fluid comprises biological actives, for example osteogenic and/or chondrogenic agents.

In embodiments of the invention the fluid comprises cells and/or tissue fragments, for example a platelet rich concentrate. In embodiments of an invention in which a pre-determined amount of fluid will be completely absorbed by the scaffold, there is no requirement for the apparatus to be provided with a fluid outlet, as there will not be any excess fluid However, in alternative embodiments of the invention in which a larger amount of fluid is to be drawn through the scaffold than can actually be absorbed by. it, then the apparatus can be provided with a fluid outlet. This fluid outlet can feedback to the fluid inlet so that the fluid can be drawn through the scaffold more than once, or alternatively the excess fluid can be sent to waste. In embodiments of the invention the apparatus is made of a material that can be sterilised.

In embodiments of the invention the apparatus or components thereof are disposable.

Once the fluid has been drawn through the scaffold, the scaffold is removed from the apparatus and then immediately used or stored.

In embodiments of the invention the kit comprises at least one housing and a plurality of scaffolds. In embodiments of the invention the kit comprises at least one chamber, a scaffold and a fluid detection means for association with the chamber or the scaffold. DETAILED DESCRIPTION OF THE INVENTION

Figure 1. Diagrammatical representation of the apparatus with a Trufit™ osteochondral plug loaded.

Figure 2: Method of introducing the fluid onto the three-dimensional scaffold.

Figure 3: Method of removing the Trufit™ osteochondral plug from the apparatus.

Figure 1: Illustrates the apparatus (1) which is substantially cylindrical having a base (2), an openable lid (3) and a circular side wall (4). A scaffold holding chamber (5) which is dimensioned to receive the Trufit™ osteochondral plug (6) is centrally located within the apparatus. A fluid inlet (7) traverses the top surface of the lid. A fluid permeable membrane (8) having the same dimensions as the lid is located between the fluid inlet and the upper surface of the scaffold. Fluid introduced through the fluid inlet collects on the membrane (8), forming a reservoir. A button (9) is an actuating means which when depressed produces a vacuum within the scaffold holding chamber (5) and draws fluid from the reservoir towards the top surface of the plug (6) and downwards through the plug. A fluid level indicator (10) is located on the side of the scaffold. In this embodiment wetness causes a colour change within the indicator. A coiled spring (11) wrapped around the outside of the inner chamber (5) and used as described in Figure 2 to facilitate the removal of the plug (6) from the inner chamber (5).

Claims

1. An apparatus for actively loading a fluid onto a 3-dimensional scaffold, the apparatus comprising;

(a) a chamber for receiving the scaffold, wherein an outer wall of the chamber is provided with an aperture through which the scaffold is insertable into and removable from the chamber;

(b) a fluid inlet associated with the chamber, the inlet being located such that when the fluid is introduced into the chamber it pools and forms a reservoir at a surface of the scaffold;

(c) an actuating means associated with the chamber, upon activation of which the fluid is conveyed from the reservoir through the scaffold.

2. The apparatus according to claim 1 , wherein the actuating means produces a vacuum which draws the fluid through the scaffold.

3. The apparatus according to claim 1 or 2, wherein a fluid permeable membrane is associated with the scaffold and the fluid pools on this membrane.

4. The apparatus according to claim 1 or 2, wherein the apparatus further comprises a fluid detecting means.

5. The apparatus according to claim 3, wherein the fluid detecting means is associated with the chamber.

6. The apparatus according to claim 3, wherein the fluid detecting means is associated with the scaffold.

7. The apparatus according to any of claims 1 to 5, wherein the apparatus further comprises a fluid outlet.

8. The apparatus according to claim 6, wherein the fluid outlet is in fluid communication with the fluid inlet such that the fluid recirculates.

9. The apparatus according to any of claims 1 to 6, wherein the scaffold is a medical implant.

10. A method of actively loading a fluid onto a 3-dimensional scaffold, the method comprising the steps of;

(a) providing the apparatus according to any of claims 1 to 9;

(b) inserting the scaffold into the chamber;

(c) introducing the fluid through the fluid inlet;

(d) activating the actuating element to convey the fluid through the scaffold.

11. A method according to claim 10, wherein the activation of the actuating element produces a vacuum which draws the fluid through the scaffold.

12. A kit comprising a chamber according to claim 1 and a scaffold.

13. Apparatus, methods and kits as substantially herein described with reference to the accompanying description, Examples and

Figures.

14. Apparatus methods and kits as substantially herein described with reference Figures 1 , 2 and 3.