GB2170127A

GB2170127A - Orthopaedic instruments

Info

Publication number: GB2170127A
Application number: GB08601490A
Authority: GB
Inventors: Richard Robert Harvey Coombs
Original assignee: National Research Development Corp UK
Current assignee: National Research Development Corp UK
Priority date: 1985-01-24
Filing date: 1986-01-22
Publication date: 1986-07-30
Also published as: GB2170127B; GB8501837D0; GB8601490D0; DE8601068U1; JPS61133015U; JPH0438812Y2

Abstract

An orthopaedic instrument for use in biopsy or similar procedures comprises three elongate members (10, 32 20,30) of different lengths mutually longitudinally and slidably interconnected as the inner (30), middle (20) and outer (10) members in a separate telescopic assembly; the inner member being the longest, having a knob handle (32) at one end of the assembly, and being solid at the other end; the middle member being a sleeve (21) having a T-bar handle (22) at said one end a short portion (24) of reduced wall thickness terminating in hole saw teeth (23) at said other end; and the outer member being the shortest and a sleeve (11) having a pistol grip handle (12) at said one end and bone-penetrating projections (13) from said other end. <IMAGE>

Description

SPECIFICATION Orthopaedic instruments This invention concerns orthopaedic instruments and more particularly such instruments suited to use in a bone biopsy procedure.

In a case where a bone tumour is thought to exist it is appropriate.to conduct a biopsy involving bone material samples taken from a number of locations distributed over the bone so that both the nature and the extent of the tumour can be determined. At present, a routine procedure for this purpose involves making a major incision for access to the bone whereby the desired samples can be taken, the samples commonly being excised in fragmented form by use of an osteotome. However, this procedure is disadvantageous insofar as it introduces a risk of extensive tissue necrosis and tumour spread along the incision. This risk may not be pertinent if the bone condition is such as to require early surgery for tumour removal by way of a similar major incision, but such surgery is not a necessary consequence and the risk is then significant.

An object of the present invention is to ameliorate this situation by the provision of an instrument allowing the removal of bone material samples for biopsy examination in a less disruptive manner.

According to the invention there is provided an orthopaedic instrument comprising three elongate members of respectively different lengths, mutually longitudinally and rotatably slidably interconnected as inner, middle and outer members in a telescopic assembly, and being successively separable from the assembly at one end thereof and individually projectable at the other end thereof; the inner member being the longest member, having a handle of knob form at said one end, and being solid and blunt at said other end; the middle member being a sleeve having a handle of T-bar form at said one end and a relatively short longitudinal portion of reduced wall thickness terminating in teeth therearound at said other end to form a hole saw; and the outer member being the shortest member and in the form of a sleeve having at said one end a handle of pistol grip form and greater transverse extent than said T-bar handle, and having at said other end longitudinal projections to penetrate the bone.

A more detailed appreciation of the invention can be gained from consideration of the presently preferred embodiment thereof, given by way of example, as illustrated in longitudinal section in the accompanying drawing.

The illustrated instrument is shown as a mutually-separable telescopic assembly of three elongate members of which the radially outermost, middle and innermost are respectively denoted at 10, 20 and 30. These members are of respectively different lengths, with member 10 being the shortest and member 30 being the longest.

The outermost member 10 comprises a sleeve 11 of circular section having towards one end a han dle 12 of pistol grip form extending therefrom generally in the manner of a pistol grip, and a small number of relatively short spikes or other axial projections 13 at its other end to penetrate a bone for purposes of stability.

The middle member 20 comprises a sleeve 21 of circular section slidably and rotatably received within the sleeve of member 10. The member 20 has at its one end a T-bar handle 22 of lesser transverse extent than the pistol grip handle 12 and is formed with teeth 23 around its other end to serve as a hole saw. In this last connection, it will be noted that a short longitudinal portion 24 of sleeve 21 at its other end is of reduced wall thickness to allow for the set of the saw teeth, the teeth extending transversely no further than the rest of the sleeve.

The innermost member 30 comprises a solid rod 31 of circular section having a knob form handle at its one end and being blunt at its other end.

Use of this instrument involves application of the whole assembly to a local small incision leading to the bone of interest, with the innermost member 30 serving as a blunt trocar to separate the tissue and to indicate location against the bone. The outermost member 10 is then gripped and urged to penetrate the bone with its spikes 13, the innermost member 30 removed, the middle member 20 gripped and rotated to cut a bicortical core sample, and the members 20 and 30 removed. Thereafter the member 10 can be separated and member 30 reinserted in member 20 to expel the cut sample for analysis.

The particular choice of the different handle forms for the three members of the instrument is beneficial in facilitating what is otherwise a difficult procedure for a single operative using two hands in close proximity.

Lastly, it is to be noted that, while the invention has particular utility in bone biopsy procedure, other applications are possible. For example, it has been found that some relief can be given to conditions in which avascular necrosis of bone occurs by boring the affected bone, and the present instrument is suitable for this purpose.

Claims

CLAIM

1. An orthopaedic instrument comprising three elongate members of respectively different lengths, mutually longitudinally and rotatably slidably interconnected as inner, middle and outer members in a telescopic assembly, and being successively separable from the assembly at one end thereof and individually projectable at the other end thereof; the inner member being the longest member, having a handle of knob form at said one end, and being solid and blunt at said other end; the middle member being a sleeve having a handle of T-bar form at said one end and a relatively short longitudinal portion of reduced wall thickness terminating in teeth therearound at said other end to form a hole saw; and the outer member being the shortest member and in the form of a sleeve having at said one end a handle of pistol grip form and greater transverse extent than said T-bar handle, and having at said other end longitudinal projections to penetrate the bone.