U.S. patent number 3,667,456 [Application Number 05/090,914] was granted by the patent office on 1972-06-06 for hip-joint operations.
This patent grant is currently assigned to Chas. F. Thackray Limited. Invention is credited to John Charnley.
United States Patent |
3,667,456 |
Charnley |
June 6, 1972 |
HIP-JOINT OPERATIONS
Abstract
A method for re-attaching the great trochanter to the femur in
which the faces to be joined are shaped respectively by matching
male and female reamers so that one fits into the other to create
an interlocking action. Suitable male and female reamers,
preferably of conical or frusto-conical form are described.
together with holders for the reamers.
Inventors: |
Charnley; John (Hale,
EN) |
Assignee: |
Chas. F. Thackray Limited
(Leeds, Yorkshire, EN)
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Family
ID: |
10479432 |
Appl.
No.: |
05/090,914 |
Filed: |
November 19, 1970 |
Foreign Application Priority Data
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Nov 25, 1969 [GB] |
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57,539/69 |
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Current U.S.
Class: |
606/81;
606/89 |
Current CPC
Class: |
A61B
17/1668 (20130101); A61B 17/1666 (20130101) |
Current International
Class: |
A61B
17/16 (20060101); A61b 017/16 (); A61b
017/32 () |
Field of
Search: |
;128/92R,92B,92BA,92BB,92F,92G,305 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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549,999 |
|
Dec 1942 |
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GB |
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1,020,421 |
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Nov 1952 |
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FR |
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1,031,888 |
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Mar 1953 |
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FR |
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Other References
Blount, W. P., "Blade-Plate Internal Fixation For High Femoral
Osteotomies." Jour. Bone and Joint Surg., Vol. XXV, No. 2, pp.
319-338, Apr. 1943. .
Osborne, Geoffrey, "An Osteotomy Fixation Plate," The Lancet, Dec.
19, 1964, pp. 1,315-1,316. .
Salenius, Pentti, "A New Compression Plate for the McMurray
Displacement Hip Osteotomy." Jour. Bone & Joint Surg., Vol. 52
A, No. 2, March 1970, pp. 382-383..
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Primary Examiner: Pace; Channing L.
Claims
What I claim is:
1. A method of re-attaching the great trochanter to the femur
comprising the steps of shaping a face of said great trochanter and
a face of said femur one by a male reamer and the other by a female
reamer to form complementary socket and spigot formations; placing
said faces one on the other so that said socket and spigot
formations interlock; and mechanically securing said great
trochanter and femur in their relative positions with said
formations interlocked.
2. A method as claimed in claim 1 wherein said socket and spigot
formations are of conical form.
3. A method as claimed in claim 1 wherein said socket and spigot
formations are of frusto-conical form.
4. A method as claimed in claim 1 wherein said spigot formation is
formed on said femur and said socket formation is formed on said
great trochanter.
5. A method as claimed in claim 2 wherein said cone is of obtuse
angle.
Description
This invention relates to techniques of hip-joint surgery, and to
apparatus for use in such techniques.
A well-known procedure in the surgery of the hip-joint, used to
gain access to the interior of this joint, is to cut the great
trochanter away from the bone of the femur, elevate it together
with its attached muscles, and thereafter proceed with the
operation inside the joint. At the end of the operation the
detached trochanter has to be re-attached to the bone, preferably
in a position slightly more lateral to its original site.
The known method of re-attachment involves fixing together two flat
surfaces of contact by mechanical fixing means such as screws,
nails, staples or wire in various forms, and such methods are a
source of great dissatisfaction in hip-joint surgery. There is a
strong tendency for the trochanter to become detached, since this
can rotate on the flat surface of the femur and so strain the
mechanical fixing means, and for a fibrous union to occur between
the trochanter and the femur.
From a first aspect the invention comprises a method of
re-attaching the great trochanter to the femur in which the faces
to be joined are shaped respectively by matching male and female
reamers so that one fits into the other to create an interlocking
action.
From another aspect, the invention provides apparatus for use in
hip-joint surgery, the apparatus comprising a pair of reamers, one
having a male working surface and the other a female working
surface, the surfaces of the reamers matching so that reamed
surfaces produced by the reamers will be a close fit one within the
other.
In use, preferably the female reamer is used to fashion a male
surface on the femur, and the male reamer is used to fashion a
female surface on the detached trochanter. Thus, when the parts are
reunited a spigot will enter a socket to give an improved
mechanical engagement. This interlocking of the bones is considered
to protect the mechanical means fixing the bones together, both
from strain and from cutting out of the bone. Furthermore, the
reamed surfaces provide a much larger contact area between raw bone
than is available with previous methods where the surfaces tend to
touch only at three or four points.
Preferably each working surface is generally conical or
frusto-conical, and is provided with teeth over a substantial part
of the surface. In the reamer with the female working surface the
conical or frusto-conical surface conveniently ends in a rim,
chamfered to the same angle as the working surface and provided
with a number of cutting teeth formed axially of the conical or
frusto-conical surface.
The cone angle is preferably obtuse. However, the angle may be a
right angle or an acute angle. Forms other than conical or
frusto-conical may be used, and the arrangement of teeth on the
working surfaces may take any one of a number of forms.
The reamers may be designed to be mounted in a manually turnable
T-shaped handle, or to be mounted on a light weight brace.
An embodiment of male and female reamers according to the invention
will now be described in more detail, by way of example only, with
reference to the accompanying drawings in which:
FIGS. 1 and 2 are a cross section and end elevation respectively of
a male reamer;
FIGS. 3 and 4 are a cross section and end elevation respectively of
a female reamer;
FIG. 5 shows a handle for the reamers to a reduced scale; and
FIG. 6 shows alternative mounting means, again to a reduced
scale.
As shown in FIGS. 1 and 2 a male reamer has a generally conical
working surface 1 formed with a plurality of rasp teeth 2 over the
full face of the cone. Towards the apex of the cone three flutes 3
are cut transverse to the axis of the cone, adjacent flutes being
separated by a cutting edge 4. The reamer has an axial hole 5
formed at one end thereof, and provided with an internal screw
thread 6. The cone angle, that is the angle .alpha., is
110.degree..
FIGS. 3 and 4 show a female reamer for use in conjunction with the
male reamer of FIGS. 1 and 2. This female reamer has a generally
conical working surface 10, again having a cone angle .beta. of
110.degree.. Rasp teeth 11 are formed over the full face of the
cone, and are similar in form to the teeth on the male reamer. The
surface 10 ends in a rim 12, chamfered at 13 to the same angle as
the surface 10, and the rim is interrupted at intervals by grooves
14 to form upstanding teeth 15 extending axially of the conical
surface. The base 16 of the reamer is formed with an axial bore 17,
provided with an internal screw thread 18.
The cone angles and tooth arrangement on the male and female
reamers are similar, and accordingly when one is used on the
trochanter and one on the femur the bones will be shaped to
matching socket and spigot formations which will be a close fit one
within the other.
It will be appreciated that the cone angle may be varied as
desired, as may the formation and arrangement of the teeth. The
reamers need not be conical, but may be cylindrical or have
matching curved working surfaces. The working surfaces should be
substantially a surface of revolution about the axis, but deformed
by the teeth. The teeth are preferably made by actual working of
the conical surface, but if desired a toothed lining material may
be secured to a smooth base surface.
FIG. 5 shows a handle with which either reamer may be associated.
The handle has a stem 20 terminating at one end in a cross piece 21
and at the other in an externally screw threaded part 22 which can
mate with the threads 6 or 18 of either the male or female reamer.
The reamer may thus be rotated to cut the bone by manual rotation
of the cross piece 21 about the axis of the stem 20.
Alternatively either reamer may be used in conjunction with a light
weight brace, when a holder as shown in FIG. 6 may be employed.
This holder has an end 30 threaded to engage the threads 6 or 18 of
either the male or female reamer. At the other end of a stem 31 is
a sleeve 32 formed with a slot 33. The sleeve may fit on to the end
of a light weight brace and be locked in position by a locking
screw 34 threadably engaging the end 35 of the slot 33.
It will be appreciated that other forms of holder for the reamers
may be designed, and the reamers themselves may have mounting means
other than the threaded holes described.
* * * * *