CN101803945A - Static hip screw used for treating femoral intertrochanteric unstable fracture - Google Patents

Abstract

The invention relates to medical equipment of orthopedic implants, in particular to a static hip screw used for treating femoral intertrochanteric unstable fracture, which comprises a lag screw, a locking screw, a side steel plate and a sleeve connected with one end of the side steel plate, wherein the inner front segment of the sleeve is provided with a front internal thread, the front internal thread is in threaded connection with the lag screw, the inner rear segment of the sleeve is provided with a rear internal thread, and the locking screw is in threaded connection with the rear internal thread. The invention aims to design a static hip screw used for treating the femoral intertrochanteric unstable fracture so as to firmly fix the femoral intertrochanteric unstable fracture and maintain the fracture stability well until fracture healing. Compared with the prior art, the invention has the characteristic of firm static fixation, can provide more selections in operation for doctors and significantly reduces the incidence rate of coxa vara, femoral neck shortening and lag screw looseness and other complicating diseases clinically, and the curative rate is high.

Description

A kind of firm static hip screw that is used for the treatment of the femoral intertrochanteric unstable fracture

Technical field

The present invention relates to orthopaedics implant medical apparatus and instruments, particularly a kind of firm static hip screw that is used for the treatment of the femoral intertrochanteric unstable fracture.

Background technology

Since the seventies in 20th century, dynamic hip screw is " goldstandard " of treatment intertrochanteric fracture of the femur always, but when the treatment unstable fracture, coxa vara, neck of femur cripetura, rotation, nonunion and the first-class complication rate of screw cutting femur are still higher, there is report to reach 22.4%～42.85%, therefore has the scholar not recommend the working power hip screw abroad for the unstability intertrochanteric fracture of the femur.

The dynamic property hip screw has easy to operate, and the power pressurization that fixing advantage, the especially lag screw slippage design in sleeve strong and the power pressurization forms is considered to one of major advantage.But the power pressurization of dynamic property hip screw is a principal element of dynamic property hip screw treatment femoral intertrochanteric unstable fracture failure.When Evans I, II type fracture, because fracture face is stable, the power pressurization makes the tight phase embedding of fracture face also constantly obtain useful stress stimulation, accelerating union of bone fracture.But when EvansIII, IV type fracture, the fracture end instability, the ability that does not have mutual supporting ﹠ stablizing between the bone piece, at this moment the power pressurization of dynamic property hip screw will make fracture site under the effect of stress by compression, rotation, in turn over, that mode such as screw cutting reaches fracture is stable again, pulverize seriously more, just go through evil more for reaching the stable distortion that takes place between the fracture site.A lot of clinically doctors have observed the existence of the complication such as the displacement fracture that the power pressurization caused, coxa vara, the cripetura of trouble limb and femoral head and neck rotation of dynamic property hip screw.

Summary of the invention

The objective of the invention is to design a kind of firm static hip screw that is used for the treatment of the femoral intertrochanteric unstable fracture, make it can play strong fixing, keep fracture stabilization well until union of fracture to the femoral intertrochanteric unstable fracture.

In order to achieve the above object, the present invention adopts following technical solution: a kind of firm static hip screw that is used for the treatment of the femoral intertrochanteric unstable fracture, comprise lag screw, side steel plate and be connected the sleeve of side steel plate one end, leading portion is provided with preceding female thread in telescopic, preceding female thread is threaded with lag screw, it is characterized in that it also is provided with lock screw, back segment is provided with the back female thread in telescopic, and lock screw is threaded with the back female thread.

Described lock screw is connected and composed by head of screw that is provided with screw thread and polished rod.

During use, be screwed into lock screw, withstand the tail end of lag screw, thereby make lag screw in sleeve, can not produce the compression slippage with lock screw at the sleeve afterbody.At this moment the firm static hip screw forms " firm static is fixed " as " bridge-type steel plate " to fracture.Owing to eliminated the power pressurization, when firm static hip screw fixedly during unstable fracture, the stress that acts on fracture site is born by lag screw and side steel plate fully, thereby makes the bone piece of fracture site keep stable, prevents complication such as coxa vara, neck of femur rotation and screw cutting.

Description of drawings

Below in conjunction with drawings and Examples invention is described in further detail.

Fig. 1 is a present embodiment structural design sketch map.

The specific embodiment

As shown in Figure 1, present embodiment comprises lag screw 4, lock screw 1, side steel plate 2 and is connected the sleeve 5 of side steel plate one end, wherein, female thread 6 before leading portion is provided with in telescopic, preceding female thread 6 is threaded with lag screw 4, back segment is provided with backfemale thread 3 in telescopic, and lock screw 1 is connected with back femalethread screw thread 3; Described lock screw 1 is connected and composed by head of screw 7 that is provided with screw thread and polished rod 8.Be screwed into lock screw 1 at the sleeve afterbody, withstand the tail end of lag screw 4, thereby make lag screw in sleeve, can not produce the compression slippage with lock screw 1.

During use, lock screw is imbedded in the sleeve, makes the hip screw overall structure keep available dynamic hip screw contour structures characteristics, also is fit to original pressurization tail nail simultaneously, so can select for the doctor provides in the more art, brings convenience to structural improvement simultaneously.

Clinical practice

1 data and method

1.1 physical data is originally organized 48 examples, male 26 examples, women 22 examples, 30～91 years old age, average 68.4 years old.Left side 21 examples, right side 27 examples.According to the Evans typing, IIIA type 36 examples,IIIB type 3 examples, IV type 7 examples, anti-tuberosity Evans V-type 2 examples.Traumatogenic reason is for getting injured by a fall 22 examples, traffic accident injury 20 examples, Falling Injury 6 examples.Merge internal disease 27 examples, hypertension 9 examples wherein, diabetes 7 examples, arrhythmia 5 examples,chronic bronchitis 3 examples, incomplete 2 examples of kidney merit, emphysema 1 example.Hinder the back to operating time 2d～7d, average 3.82d.

1.2 it is the described structural design (see figure 1) of present embodiment that present embodiment firm static hip screw is used the firm static hip screw of this clinical practice.

1.3 prepare before the art of operation method firm static hip screw operation, position in the art, reset, operative approach and internal fixation install with the operation of dynamic property hip screw without any difference.After internal fixation installs and fixes, be screwed into lock screw, withstand the tail end of lag screw, thereby make lag screw in sleeve, can not produce the compression phorogenesis with lock screw at the sleeve afterbody.Note in the art that lag screw length is advisable with the flat lateral side of femur cortex of its afterbody, lock screw is screwed into the degree of depth will just withstand the lag screw afterbody, should avoid being screwed into fracture end being separated or to be screwed into the degree of depth not enough and do not have a locking action.

1.4 post surgery treatment postoperative 2d～hip is carried out in the 3d bed, knee joint is bent and stretched activity, 1 Zhou Houke sits up, and holds up after 3～6 weeks and turns down ground, bears a heavy burden until union of fracture gradually according to fracture stabilization degree and union of fracture situation.

2 results

This is organized in 48 examples 43 examples and obtains and follow up a case by regular visits to, and follows up a case by regular visits to 8～23 months time, average 11 months.All fracture all healed in 11～20 weeks, and The average healing was 14 weeks, complication such as no coxa vara, incidence rotation, lag screw cutting femur head and neck and internal fixation fracture.Press joint criterions of therapeutical effect such as Dong Jiyuan, excellent: union of fracture, hip does not have pain, level, totally 21 examples before the osteoarthrosis activity returns to and hinders; Very: union of fracture, hip idol have pain, osteoarthrosis activity major part to return to wound preceding situation, totally 19 examples; Can: union of fracture has slight coxa vara, osteoarthrosis limitation of activity, pain, totally 3 examples sometimes; Difference: malunion of fracture or not healing, hip pain can not out-of-bed activity.This group indifference level case.This group acceptance rate is 93%.

In sum, the present invention compared with prior art has the following advantages:

1, firm static fixation.Because lag screw can not produce slippage in sleeve, at this moment present embodiment forms " firm static is fixed " as " bridge-type steel plate " to fracture.

2, improve unstable fracture treatment acceptance rate between tuberosity.The clinical observation of this group case is difficult complication and takes place, acceptance rate be the slight coxa vara patient of 93%, 6 example be reset not exclusively in the art due to.

3, the sleeve after the improvement is suitable for prototype pressurization tail nail equally, so can select for the doctor provides in the more art.

4, obviously reduced the incidence rate that coxa vara, neck of femur cripetura and lag screw move back complication such as nail.Owing to eliminated the power pressurization, when present embodiment fixedly during unstable fracture, the stress that acts on fracture site is born by lag screw and side steel plate fully, thereby makes the bone piece of fracture site keep stable, prevents complication such as coxa vara, neck of femur cripetura and screw cutting.From the clinical practice of this group, biomechanics aspect defective that present embodiment has existed when having overcome unstable fracture between prior art resected femur tuberosity has obviously reduced the incidence rate that coxa vara, neck of femur cripetura and lag screw move back complication such as nail.

Claims (2)

1. firm static hip screw that is used for the treatment of the femoral intertrochanteric unstable fracture, comprise lag screw (4), side steel plate (2) and be connected the sleeve (5) of side steel plate one end, leading portion is provided with preceding female thread (6) in telescopic, preceding female thread (6) is threaded with lag screw (4), it is characterized in that it also is provided with lock screw (1), back segment is provided with back female thread (3) in telescopic, and lock screw (1) is threaded with back female thread (3).

2. a kind of firm static hip screw that is used for the treatment of the femoral intertrochanteric unstable fracture according to claim 2 is characterized in that described lock screw (1) is connected and composed by head of screw that is provided with screw thread (7) and polished rod (8).

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