WO2002096308A1

WO2002096308A1 - Surgical device

Info

Publication number: WO2002096308A1
Application number: PCT/AU2002/000664
Authority: WO
Inventors: John Trantalis
Original assignee: John Trantalis
Priority date: 2001-05-28
Filing date: 2002-05-27
Publication date: 2002-12-05
Also published as: AUPR527401A0

Abstract

A surgical device is disclosed. The device is a donut-shaped flexible inflatable occlusive seal (10) for a bone canal which will assist in pressurization of cement during shoulder and hip arthroplasty. A cement gun nozzle is placed through a hole (14) in the centre of the device (Fig 5) and the device is then placed in the opening of a bone canal (Fig 6) and inflated via a tube (18) to occlude the opening and form a tight seal. As cement is injected via the cement gun, the tight occlusive seal provided by the device prevents cement escape and thus allows pressurization of the injected cement within the bone canal (Fig 6). A tube (22) allows drainage of any excess blood. The device is deflated via the tube (18) and removed, leaving the bone canal full of cement and ready for implantation of the prosthesis.

Description

surgical device

Field of the invention

This invention relates to a surgical sealing device for use in arthroplasty surgical procedures and a method of using this device. Background of the invention

As a result of advances in medicine and surgical techniques, individuals with irreparable damage to joints, such as hips or shoulders, can undergo joint replacements, or arthroplasty. For example in hip replacement operations (hip arthroplasty) a suitable prosthesis is inserted into the canal of the proximal femur. It is common practice during arthroplasty operations to insert a cement (typically polymethylmethacrylate cement) into the femoral canal prior to implantation of the femoral prosthesis. Additionally, it is advantageous to pressurize the cement to improve the interlocking between cement and bone and potentially increase the lifespan of the arthroplasty. During hip arthroplasty, cement pressurisation is typically achieved by inserting cement with a cement gun, with the flow of cement down the shaft being blocked by a cement restrictor, and back up the shaft by occluding the opening. Various mechanical devices are currently used to occlude this opening. For example, a rectangular or wedge- shaped rubber block may be pushed into the canal opening. Alternatively the surgeon may use one or more sponges or their gloved fingers in an attempt to occlude the canal opening. A drawback of each of these occlusion methods is that the devices do not conform well to the variable shape and size of the femoral canal opening, with the result being an inadequate seal, leakage of cement and inadequate pressurization.

Summary of the invention According to a first aspect of the invention there is provided a surgical sealing device for use in achieving an occlusive seal inside an opening to a bone canal during arthroplasty surgical procedures, said sealing device including:

- a flexible inflatable member surrounding a central cavity through which cement may be inserted into said bone canal; and - inflation means to enable said inflatable member to be inflated; wherein in use, said flexible member when inflated conforms to the shape of the bone cavity into which it is inserted thereby forming an occlusive seal.

Preferably said inflatable member is an annular member or a toroidal member. Preferably said inflation means comprises a tube through which a suitable substance can be passed to inflate or deflate said inflatable member, and a valve which in the open position allows said inflatable member to be inflated or deflated and which in the closed position prevents the escape of said suitable substance from the inflatable member when inflated. Preferably said suitable substance is either sterile saline or air.

Preferably said sealing device further includes a compressible auxiliary sealing member attached to the outer rim of said inflatable member, said auxiliary sealing member designed to improve contact with the inner wall of said bone cavity providing an improved occlusive seal. In a preferred embodiment said sealing device further includes a tube attached to an inner portion of said inflatable member to enable the removal of excess blood or other fluid from said bone cavity during cement pressurization.

According to another aspect of the present invention there is provided a method of occluding the opening of a bone canal to achieve cement pressurisation during an arthroplasty surgical procedure using a sealing device, said sealing device including a flexible inflatable member surrounding a central cavity and an inflation means to enable inflation of said inflatable member, wherein said method includes the steps of:

- inserting the nozzle of a cement applicator gun into said cavity of said sealing device; - inserting said sealing device and cement applicator gun nozzle into the opening of said bone canal into which cement will be injected;

- inflating said inflatable annular member via said inflation means to occlude said canal opening; the occlusive seal provided by said sealing device prevents the reflux of cement - injecting cement into said bone canal using said cement appHcator gun wherein from said bone canal allowing cement pressurisation; and,

- deflating and removing said sealing device when cement pressurization is achieved.

Preferably inflation of said inflatable annular member is achieved using a syringe attached to said inflation means, wherein the syringe is filled with either sterile saline or air.

In preferred embodiments of all aspects of the present invention said flexible inflatable member is constructed from pliable rubber.

The flexible inflatable member of the present invention may be constructed in any suitable size depending on the specific purpose for which it is intended.

Brief description of the drawings

Features and embodiments of the present invention will now be described by way of non-limiting examples, with reference to the drawings, in which:

Fig. 1 illustrates a surgical sealing device according to a preferred embodiment of the present invention;

Fig. 2 illustrates a surgical sealing device according to a further emDodiment of the present invention; and Figs. 3 to 5 outline the steps of a method of use of the surgical sealing means of Fig. 1 in an arthroplasty operation according to the present invention.

Detailed description of the embodiments

The surgical sealing device of the present invention is designed for use in arthroplasty, or joint replacement operations, where cement is injected into the medullary canal of a bone prior to implantation of a prosthesis and pressurization of this cement is desired. Specifically the sealing device is most applicable to hip or shoulder arthroplasty surgical procedures. The sealing device of the present invention provides an occlusive seal inside the opening of the bone canaL such as the opening of the proximal femoral canal, and enables cement to be suitably pressurized without leakage or reflux of cement. Fig. 1 depicts a surgical sealing device 10 according to one particular embodiment of the present invention. The sealing device 10 includes a donut-shaped or toroidal inflatable chamber 12 surrounding a central cavity 14. The cavity 14 is designed to be of suitable size to allow the nozzle of a cement appHcator gun to be inserted therethrough. The inflatable chamber 12 includes inflation means in the form of a tube 16. One end of the tube is located inside the chamber 12 and the other end outside the chamber has a valve 18 attached.

The valve 18 and tube 16 enable the chamber 12 to be inflated for use and deflated after use. For example a syringe, filled with either a sterile saline solution or air may be appHed to the outer end of the tube 16, the injection of the sterile saline or air causing the chamber to be inflated. It will be appreciated that other forms of inflation of the chamber are also possible without departing from the scope of the invention. Varying amounts of sterile saline or air may be injected into the chamber 12 depending upon the size to which the chamber is required to be inflated in order to achieve an occlusive seal. It w be appreciated that the sealing device 10 should be flexible such that when the inflatable chamber is inflated the chamber firmly contacts the inner wall of the bone cavity into which it is inserted thereby forming an occlusive seal. Preferably the chamber 12 is constructed of rubber or any other suitably pfiable and flexible material to enable the chamber 12, upon inflation via the inflation means, to conform to the particular shape of the bone into which it is inserted, with further inflation attowing it to push tightly on the inner watt of the bone canal opening, and thus form a tight occlusive seal.

It wfll be further appreciated that the sealing device 10 may be constructed in any suitable size depending upon the particular appHcation for which it is designed. For example it is likely that various sizes of sealing device will be required for use in patients of different sizes and for different arthroplasty procedures, such as hip or shoulder arthroplasty.

Fig. 2 shows the surgical sealing device of Fig. 1 with various modifications made thereto. The outer rim of the inflatable chamber 12 may be fitted with a compressible material, such as foam or sponge, to serve as an auxiliary sealing member 20 designed to improve the contact between the sealing device and the inner waU of the bone and thereby improve the occlusive seal. Additionally, a tube 22 may be connected to the inner rim of the inflatable chamber 12 as shdwn in Fig 2. One end of this tube may extend below the lower surface of the sealing device and allow for the removal of excess blood or other fluid from the bone canal during cement pressurization. Alternatively, the tube 22 need not be attached directly to the inflatable chamber 12 but rather may be inserted into the cavity 14 of the sealing device along with the nozzle of the cement appHcator gun.

It should be noted that the sealing device 10 may include either the gripping means 20 or the tube 22 as shown in Fig. 2, or may include both of these features.

Turning now to Figs. 3 to 5, a method of use of the above-described sealing device is iflustrated by way of example in a hip arthroplasty surgical procedure. The surgeon prepares the bone canal, and the inserts a cement restrictor deep in the canal to block cement flowing too far down the canaL The surgeon then fills the depths of the bone canal with a cement gun. Once nearly fiHed, the surgeon then withdraws the gun.

The inflatable chamber 12 is shown deflated in Fig. 3. The nozzle of a cement appHcator gun fiHed with the remaining cement is inserted into the cavity of the sealing device while the chamber 12 is deflated. A syringe filled with sterile saline is attached to the inflation means of the chamber. Once the proximal femoral canal has been cleared of debris and prepared by the surgeon for the injection of cement, the deflated sealing device, together with the attached syringe and cement appHcator gun, is placed in the opening to the femoral canaL

As illustrated in Fig. 4 the injection of sterile saline from the syringe into the inflatable chamber df the sealing device inflates this chamber. The chamber is inflated with sterile saline until the chamber is of sufficient size to contact the inner waU of the femoral canal opening with further inflation aflowing the sealing device to push firmly against the inner waH of the bony canal opening, and thus form an occlusive seal., Once inflation is complete the valve of ihe inflation means (18 in Fig. 1) is closed to prevent deflation of the chamber. The flexible and pKable nature of the chamber of the sealing device enables the shape of the chamber to conform to the precise shape and conformation of the femoral canal, with further inflation aflowing a tighter occlusive seal.

The syringe may remain attached to the tube inflation means of the chamber during the foHowing cement pressurization process or alternatively may be removed after inflation of the chamber is complete.

It wiH be appreciated that air may be injected into the inflatable chamber of the sealing device as an alternative to sterile saline and injection may be either via a syringe or any other suitable injection means.

Once an occlusive seal is formed (Fig. 4) cement is injected from the cement appHcator gun through the cavity of the sealing device into the femoral canal. The occlusive seal formed by the sealing device prevents any leakage of cement from the canal and thus aHows pressurization of the cement in the canal.

With reference to Fig. 5, once the proximal femoral canal has been filled with pressurized cement, the chamber of the sealing device is deflated by retraction of the syringe plug causing sterile saHue to be withdrawn from the chamber. The entire deflated device is then removed from the femoral canal opening., The proximal femur is then ready for the implantation of the femoral prosthesis. It wfll be understood that the invention disclosed and definedherein extends to aH alternative combinations of two or more of the individual features mentioned or evident from the text or drawings. AH of these different combinations constitute various alternative aspects of the invention.

The foregoing describes embodiments of the present invention and modifications, obvious to those skflled in the art can be made thereto, without departing from the scope of the present invention.

Claims

The daims defining the invention are as foHows:

1. A surgical device, comprising a donut-shaped flexible inflatable chamber surrounding a central cavity, said chamber being placed into the opening of a bone canal and then inflated, thus forming an occlusive seaL which upon insertion of cement via a cement appHcator gun through the central cavity of the chamber, prevents escape of cement and thus aHows cement pressurisation.

2. The surgical device of claim 1 wherein the chamber is constructed of rubber or any other suitably pfiable and flexible material to enable the device upon inflation to conform to the particular shape of the bone opening into which it is inserted, with further inflation aUowing it to push tightly on the inner waH of the bone canal opening, and thus form a tight occlusive seaL

3. The surgical device of claims 1 and 2 wherein the chamber is inflated and deflated by means of a tube, one end of which is located inside the chamber and the other end located outside the chamber and having a valve attached.

4. The surgical device of claims 1 to 3 wherein a syringe fitted with sterile normal saline or air is connected to the aforementioned valve and is injected through the tube to inflate the chamber, and used again later to withdraw the fluid/air and thus deflate the chamber.

5. The surgical device of claims 1 to 2, wherein it may be constructed in any suitable sizes, with various sizes of the device being required for use in patients of different sizes and for different arthroplasty procedures, such as hip or shoulder arthroplasty.

6. The surgical device of claims 1 to 5, wherein the outer rim of the inflatable chamber may be fitted with a compressible material, such as foam or sponge, to serve as an auxiliary sealing member designed to improve the contact between the sealing device and the inner wafl of the bone and thereby improve the occlusive seal.

7. The surgical device of claims 1 to 6 wherein a tube may be connected to the inner rim of the inflatable chamber but extend past its seal, and thus aHowfor the removal of excess blood or other fluid from the bone canal during cement pressurization.

8. A surgical device substantiaUy as herein described with reference to the accompanying drawings.

Dated this 22^nd day of May 2002

John Nectarios Trantalis