CS223355B1 - Hip joint endoprosthesis - Google Patents

Abstract

The acetabulum component of a hip-joint endoprothesis comprises an acetabulum cup 6, a non-metallic shell member 1 and a retaining nut 10. The shell member defines therewithin a volume 8 which is greater than hemispherical and less than spherical, having an opening around which the wall of the shell member is formed with radial slots 9. The nut 10 serves to hold the head portion of a femur shank in the volume 8 and simultaneously lock the shell member 1 in the acetabulum cup 6. In accordance with requirements, the shell member may be used with an acetabulum cup which is of self-anchoring type or to be cemented in the natural acetabulum and with a shank which is self-anchoring or to be cemented in the medullary canal of the thigh. <IMAGE>

Description

The invention relates to total hip arthroplasty, which is used in orthopedics and traumatology as a replacement for damaged natural hip joints.

Are known ^y r ^{u s} total Zn ^alkyl Celma Moutai endoprosthesis, which represent non-closable or closed detachably ^to each other undetachably ru ^t ons ^{to CE kt} and ns are fixed by bonding to the bone with bone cement, or mechanical keying. These are, for example, Thompson, Austin-Moore, Charnley-Muiler, etc. prostheses. Metal endoprostheses are very heavy and inelastic and, due to the use of bone cement, have a negative effect on both the course of the operation and postoperative conditions.

Also known is the construction in which the shaft is conical and mechanically keyed into the medullary canal of the femur, while the acetabular 'sleeve is mechanically secured in the femur by means of two screws which are at ^the oncen ^y mat ^and CEM ^I L shape

Also ·. a structure with the same shaft is known, but in which the acetabular sleeve ends with one screw intended to be screwed into the femur.

Another known construction is provided with a flat shank · · · · with smooth walls, wherein the housing acetabutarní finished stirrups sharp tan ^{yk yk} are exercised are designed for forcing ^{d b} a machined seat in the natural acetabulum.

It is also known dismountable structure with a conical shaft having two longitudinal ^{says the} ram ^{and to} tere ^{key chain} NOCs ^and on the meduterním ^to an ^AL U, kuiovrta ^PART n ^and SAD ^Y is mounted to the metallic casing of a different material, whose outer the parts are provided with teeth, which serve to anchor in the saddle of natural acetabulum.

Further, a similar construction is known with an unchangeable plastic seat with a tightening nut that allows the joint to be removed, but only during implantation.

Also known are total hip arthroplasties in which both the shaft and the acetabular capsule are fixed to the bone by bone cement.

It is known that ^{f Ké} shaft Emura unipolárrn ^KYC elrn moubata prosthesis ^to a now obsolete ^p nčné toothing with round holes at the base of the teeth.

^D o ^p en rot ^{outers, C} o ^p sleigh MS. Autors ^Ké m certificate no. 169270 by Paulist et al. having fixing shaft formed of a plasticized ^I C ^to a ^h MOTs, napřMad ^p ol ^YF ormalde ^h y ^d u or polyethy ^ entereftatatu and ^h o ^ top engaging into rubbing ^{NIVTE eh} for ^the Anat thighs ^{to the} ostium is porézrn with no ^p ravidelným ^and outpu ^p to ^y. The head on the bolt shank of the fastener to the mounting ^of the odmmatefoě napříMad ^b oustranným zajtéťovamm ^{phorous to} a reflux ^{condenser, p} u ^s T ^e Nym in Krc taavice ^to u.

^K and ^{hk sure} jmenovanýc onstru ^{to a} C totalrnc ^h · ^l n ce ^{ky I} CH ^ mh Mou · ^d o ^p en ROTEZ they have drawbacks.

Neuzavíratahta mutually rozetaratehte structure allows spontaneous dislocation Klou ^b Ph ^P Tape dimensions ^of matych and ^f un ^CZK them suffer, while lockable undetachable ^the ONS ^t ru ^to CE ^{characterized} in ^la vají pH size ^to Yc ^h and ^f un ^to ect loads breaking the femur or ky ^No. elm ^to Ostia opposed. from ^when the nee ^{h kl bu} ou esters ^to the pH and ^{to t h} ovýc maximjrnčh. loads without breaking broke out. Another major drawback of mutually unassembling constructions is their difficult implantation, which requires the cutting of a large portion of trochanter.

A significant deficiency of the hip joint prosthesis shank is conical often occurring in practice, the release shaft in the medullary canal, which leads to unstable rotation and ^KL ou ^b u is ^PRICE Nou stíných botastí that restrict the movement of each leg.

Substantial lack of individual in the world of usage of total kyčelmta ^kl oubníc ^hp ROTEZ it is ^d on ^the ones that do not allow for variations during implantation depending on the immediate clinical indications and, second, the need to replace the entire endoprosthesis or their individual parts due to broken bones · during reoperation due to failure in the postoperative period. . Thus, for example, total joint replacement metal and non-metal ball bushing wear caused by abrasion on a plastic holder frequent appearance, which makes replacement of the whole at reoperation acetabular housing by new necessary, which leads to secondary taaumatízaci ^{to the} ostium.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a total hip arthroplasty which allows the selection of the individual components of the set [femur and acetabular shells] depending on the specific clinical indications for gluing or mechanical attachment to the bones during surgery. non-traumatic replacing individual sealed not by uvotoěných ^{b p} r ^es Eventual at reoperation. To ensure stable fixation of the corresponding bones, has a structure ensuring ^{t which} just f ^y Zioła ^g ic ^Ké with ^p he concept Mou ^ those ^kt ns would correspond antiluxačním ability of the natural joint ball which must be mutually detachable in the sense easy mam ^p Ulac ^b uring o ^p eratio ns and must ^b e ^{s t} ta ^kk onstruov ^{and Na} b ^{y p} nevytajete no reward for increasing ^{alkyl with} eN ^s vnitřrnho TTE ^for UV medullary canal during deployment shaft.

This object is solved by a releasable total hip joint endoprosthesis consisting of acetabular housing and handpiece femoral interconnected nonmetallic seat and portative nut, it ^{IZ M} o ^d s ^t a ^t a spomvá in ^{that Z} e not ^to ovov ^s seat is nestled into the seat of the acetabular housing and this with ^p Ojén nerozebírateW ^p dip ^and his ^No. EPU and ^at RT ^F n ^Star nut screwed RP ^and Vita acetabuterntao ^p OUZ ^d the said metallic seat in its outer conically arranged peripheral part provided with radial incisions forming three fourths round hole and an inner conical hole portative nut is aligned with the conical shape periíerm ^CA STI ^dl AAV hUclltych fatness femoral cups are arranged oval longitudinal channels.

The acetabular sleeve can be made in two designs, either metal with a toothed outer surface for mechanical fastening or plastic that is suitable for bonding with bone cement. Also, the handpiece of the femur can be made in two variants, either rectangular, which is in its upper portion of ^{the p} ro mec ^h anic ^Ké upevnrnu provided zu ^would not ^B on the flat with ^H Ia ^d until ⁱ st ^{of us,} which is suitable for cement bonding. The handpiece joins in the desired combination simultaneously with the insertion of the femoral head in the non-metallic saddle and tightening the nut. The non-metallic seat is removably disposed in a corresponding seat of the acetabular sleeve.

The advantages of the total hip arthroplasty according to the invention are that the removable seat, in which the spherical head rotates, is non-metallic, provides minimal friction and is not subject to bimetallic corrosion, while being easily removed in case of wear without traumatization. The radial slots in its periphery allow that in joint reconstruction ob] bicyclo ^p Ovalo three quarters of rotating the spherical head and provide at tightened nut clamping joint force corresponding physiological antiluxačním ability of the natural joint, thereby preventing extraction of the acetabular shell from a femur or breakage femuru.

Furthermore, the advantage of the described total hip arthroplasty is that it meets all the requirements for these prostheses, in particular that in the saddle are mechanically or bone cement bondable components which are connected to each other by a nut and a single non-metallic saddle, giving the operator the choice reoperation in accordance with the specific clinical indications most effective method of fixation endoprosthesis.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of the acetabular housing cover for mechanical fastening; FIG. 2 is a bottom view of the acetabular housing of FIG. 1; FIG. Fig. 4 is a bottom cross-sectional view of the non-metallic housing of the present invention; Fig. 6 is a bottom view of the housing of Fig. 5; Fig. 7 is a view of the femur handpiece for mechanical bonding; FIG. 8 is a partial cross-sectional view of the tension nut of the present invention; and FIG. 10 is a bottom view of the tension nut of FIG. 9.

From the drawing it follows that the exchangeable metal seat 1 is provided with a pin 4, which rotates ^to hunt ^and the head ² NASA ^d ce ^third Cep 4 is pressed removably but non-rotatably in the hole 5 of the acetabular housing 6. In order to prevent luxation of the joint reaches the peripheral part 7 of the conical friction surfaces 8 in a non-metallic seat below an equatorial 1 - circle round ^hl AVICEL second ^p sti odel periferm ^{CA 7} are radial indentations 9 which allow the ball head 2 to be suspended under low pressure into the non-metallic seat 1. To fasten the non-metallic seat 1 in the acetabular sleeve 6 and to physiologically clamp the ball head 2 in the non-metallic seat 1, an inner weight wall 11 on the conical peripheral portion 7 with notches of a non-metallic seat 1 and secures the hinge against spontaneous dislocation. The pressing corresponds to the requirement of free rotation of the ball head 2 and the possibility of self-locking under load, which would cause a dislocation of the natural joint. This will prevent -event. fracture of the femur or rupture of the acetabular capsule 6.

As acetyl-ALN-nary sleeve 8 for mechanically fixed ^t and ^k i acetabutarm Only ^D ro 26 for bonding with bone cement has on its inner side a seat 12 for attaching a removable non-metallic saddle 1 with a bore 5 for press-fit the pin 4, and the thread 15 portative for screwing the nut 10. on the side ^of zevrn me ^c h ^ ^alkyl n'c fastened, acetabular housing 5 are provided a specially-formed teeth 14 for přiklínování in the prepared natural acetabulum seat (wells joint to the femur). The outer surface of the acetabular - sleeve 26 (made of metal or plastic) which is to be bonded with bone cement, is provided with grooves ^{15 P} ro ^fi Stabil .x.aci kostoto cement.

The femoral handpieces 3 and 23, respectively, have in the front part an elongated extension 16 which fits the cortical (cortical) contour on the femur. Thus, the handpiece 3 or 23 safely carries the weight of the body without dropping into the soft spongy tissue of the bone core. The mechanically fixed handpiece 3 is wide, rectangular, thereby preventing rotation to the femur. In its upper region, the handpiece 3 is provided with teeth 17 between which round holes 18 are drilled. The teeth 17 serve to enlarge a hole drilled in advance in the femur by special files, with a view to chipping the bone chips that fill the round holes bones. As a result of the binding of these chips in the postoperative period, a secure connection of the handpiece 3 and the femur is achieved. In its lower part, the rectangular handpiece 3 is smooth, but is provided on its four sides with longitudinal channels 19 which prevent pressure build-up in the medullary (medullary) canal when the handpiece 3 is inserted into the bone. Handpiece 23,

The 2233SS to be bonded with bone cement is narrower than the mechanically fixed handpiece 3 with respect to filling the hole in the femur with the necessary bone cement. Its cross-section is a smooth hexagon with rounded edges and oval longitudinal channels 19 extending along the outer edges of the hexagon. Its walls are smooth and the function of the oval longitudinal channels 19 is the same as that of the handpiece 3 for mechanical fastening.

The total hip arthroplasty of the invention is implanted as follows: according to the specific clinical indications for wedging or gluing, the appropriate acetabular sleeve 6 or 26 and the handpiece 3 or 23 of the femur are selected. There are four different combinations to choose from - a fully glued joint or a fully mechanically fastened joint, an glued acetabular sleeve 26 and a mechanically fastened handpiece 3 or a mechanically fastened acetabular sleeve 6 and a glued handpiece 23. The two joint parts are fixed separately to the preformed femur and femur . Then the spherical head 2 of the handpiece 3 is inserted into the spherical hole 5 of the non-metallic saddle 1 and clamped therein by the clamping nut 10. During reoperation, the joint is loosened by unscrewing the clamping nut 10 and replaced by a new one without breaking. Finally the joint is closed again.

The clinical results of the implantation of total hip arthroplasty according to the invention are fully satisfactory in terms of functionality and dynamic stability.

Claims (1)

A removable total hip arthroplasty consisting of an acetabular sleeve and a femur handpiece, connected to each other by a non-metallic saddle and a tightening nut, characterized in that the non-metallic saddle (1) is seated in the saddle (12) of the acetabular sleeve (6 or 26). by means of its pin (4) and the tightening nut (10) screwed into the thread (13) of the acetabular sleeve (6 or 26), BACKGROUND OF THE INVENTION wherein the non-metallic saddle (1) is provided in its outer conically arranged peripheral portion with radial notches (4) forming a three-quarter round hole (5) and the inner conical bore of the clamping nut (10) aligns with the conical shape of the peripheral portion (7) and oval longitudinal channels (19) are provided in the smooth regions of the femur handpiece (3 or 23).