CN203468725U

CN203468725U - Dilated hip screw of proximal femoral intramedullary nail

Info

Publication number: CN203468725U
Application number: CN201320557378.2U
Authority: CN
Inventors: 袁志; 裴国献; 刘建; 毕龙; 杨鹏; 李岩; 隋天琪
Original assignee: Fourth Military Medical University FMMU
Current assignee: Fourth Military Medical University FMMU
Priority date: 2013-09-09
Filing date: 2013-09-09
Publication date: 2014-03-12
Anticipated expiration: 2023-09-09

Abstract

The utility model relates to an internal fixation device of proximal femoral fractures, in particular to a dilated hip screw of a proximal femoral intramedullary nail. The defects that a traditional proximal femoral intramedullary nail can not achieve effective and firm fixation under the condition of rarefaction of bone, and fixing failure happens frequently are overcome. According to the technical scheme, the dilated hip screw of the proximal femoral intramedullary nail comprises a hollow hip screw and an inner core nail inside the hollow hip screw, longitudinal and equidistant cracks are arranged in the pipe wall of the head of the hollow hip screw, and thread strips which are controlled by the inner core nail and can be closed and opened elastically are formed. According to the dilated hip screw of the proximal femoral intramedullary nail, an original hip screw is replaced by the dilated hip screw, the position of the inner core nail is moved, the head of the hollow hip screw is pushed and squeezed to be dilated, surrounding cancellous bones are supported, the holding force of a proximal femoral intramedullary nail system is enhanced, and therefore the purpose of firmly fixing osteoporotic proximal femoral fractures is achieved.

Description

A kind of PFN dilatancy hip screw

Technical field

This utility model relates to a kind of fractured near end of thighbone internal fixation apparatus, is specifically related to a kind of PFN dilatancy hip screw.

Background technology

1966, Zickel invented intramedullary pin and has been used for the treatment of fracture of shaft of femur (Zickel RE.An intramedullary fixation device for the proximal part of the femur.Nine years ' experience.J Bone Joint Surg Am.1976Sep; 58 (6): 866 ?72.), knitting rate is significantly improved.The later stage eighties 20th century; Holdon and Grosse etc. have designed again the proximal femoral nail system that can treat fractured near end of thighbone; this system comprise the main nail of PFN (1), 1 ?2 pieces of hip screws (2), distal locking nail (3), main nail tail cap (4) (Boriani S, Bettelli G.The Gamma nail.A preliminary note.Chir Organi Mov.1990Jan ?Mar; 75 (1): 67 ?70.).In 57Ci U.S. orthopedist association (AAOS) meeting that nineteen ninety holds in U.S. New Orleans, first Grosse A and Taglamg G report the experience (Pei Guoxian by PFN treatment intertrochanteric fracture of the femur, Guo Gang. modern Wicresoft orthopaedics and tranmstology [M]. front page. Beijing: People's Medical Officer Press, 2008,506 ?507).After this, existing 40 multinational families, surpass 300,000 patients and have used this internal fixation apparatus in the world.At present PFN become be treatment fractured near end of thighbone main in fixing means (Miedel R, h; Ponzer S, Tidermark J.Musculoskeletal function and quality of life after an unstable trochanteric fracture treated with the trochanteric gamma nail.Arch Orthop Trauma Surg.2012Oct; 132 (10): 1495 ?503.).

The design principle of PFN is to insert femoral shaft near-end pulp cavity by main nail, again by main nail near-end to be screwed in neck of femur 1 ?2 pieces of thicker hip screws, at main nail far-end, be laterally screwed into 2 pieces of thinner distal locking nails of 1 ?and run through femoral shaft two side seam walls, complete effectively fixing fractured near end of thighbone.With DHS, DCS pegboard systems and the comparison of near end of thighbone locking steel plate of near end of thighbone, PFN has shortened the arm of force, has reduced moment of flexure, can more effectively resist cripetura and rotation, guarantees that fracture is more stable fixing.Its primary structure comprises: 1) 1 main nail of PFN: its profile is similar to common femoral interlocking intramedullary nail, but the obvious overstriking of near-end (14～17mm), and it is crooked to be outwards 6～10 degree.2) 1 ?2 hip screws: diameter is thicker, is 125～140 degree angles and runs through obliquely main nail near-end and be screwed into and in neck of femur, complete near-end and fix.3) 2 distal locking nails: diameter is thinner, length, between 30～60mm, laterally runs through main nail far-end and by femoral shaft both sides cortical bone bone wall, completes far-end and fix.4) tail cap: be placed in main nail near-end top, prevent the soft tissue intramedullary pin near-end inner chamber of growing into.According to the difference of each manufacturer's design details, concrete structure is slightly different, and its concrete appellation is also different, such as having: Gamma nail, PFN, PFNA, Intertan nail etc., these are all referred to as PFN.

But for senile osteoporosis fractured near end of thighbone, due to the serious osteoporosis of neck of femur, above various traditional PFNs simple rely on to be screwed in Cancellous bone 1 ?2 pieces of thicker hip screws fix, often can not complete effectively and fixedly secure, (Bojan AJ, Beimel C are fixed unsuccessfully in normal generation, Taglang G, Collin D, Ekholm C

a.Critical factors in cut ?out complication after gamma nail treatment of proximal femoral fractures.BMC Musculoskelet Disord.2013Jan2; 14 (1): 1).

Utility model content

This utility model object is to overcome traditional PFN can not complete effectively and fixedly secure in osteoporosis situation, and normal generation fixed failed shortcoming, proposed a kind of PFN dilatancy hip screw.

For achieving the above object, the technical scheme that this utility model adopts is: comprise Cannulated hip screw and portion's inner core nail movably within it, on described Cannulated hip screw head end tube wall, offer 2-6 longitudinally equidistant crack, form the longitudinal screw bar of being controlled elasticity opening and closing by inner core nail.

Described Cannulated hip screw head end internal diameter is thin compared with bar portion internal diameter, and tail end is provided with female thread; The tail end of inner core nail is provided with the external screw thread matching with the female thread of Cannulated hip screw tail end.

The tail end cross section of described inner core nail is provided with groove.

Described inner core nail comprises drive-in inner core nail and lift type inner core nail.

Described drive-in inner core nail comprises the circular cone tip of head end and the round bar portion of tail end, is provided with the external screw thread matching with Cannulated hip screw female thread in round bar portion.

Described lift type inner core nail comprises the spindle portion of head end and the round bar portion of tail end, is provided with the external screw thread matching with Cannulated hip screw female thread in round bar portion.

Compared with prior art, the position that this utility model is followed closely by mobile inner core, make inner core nail push the expansion of Cannulated hip screw head end, realize Cannulated hip screw head end tube wall support spongy bone around, and be provided with external screw thread at expanding hip screw head end, make PFN and spongy bone frictional force increase around, strengthen the hold of PFN, thereby reach the object that fixedly secures fractured near end of thighbone.

Accompanying drawing explanation

Fig. 1 is the structural representation of Cannulated hip screw of the present utility model;

Fig. 2 is the structural representation of propelling expanding hip screw of the present utility model;

Fig. 3 is the structural representation that lifts expanding hip screw of the present utility model.

The specific embodiment

Below in conjunction with accompanying drawing, structural principle of the present utility model and operation principle are described in further detail.

This utility model is on the basis of traditional PFN, with expanding hip screw, replaces former hip screw, and the inner core nail of expanding hip screw inside is divided into drive-in inner core nail and lift type inner core nail.

Embodiment 1: referring to Fig. 1, Fig. 2, the present embodiment comprise Cannulated hip screw 1 and within it the drive-in inner core of portion follow closely 5 two parts and form, the cephalic par of Cannulated hip screw 1 is provided with external screw thread 2, head end internal diameter is thin compared with bar portion internal diameter, and on head end tube wall, equidistantly offer 2～6 longitudinal cracks 3 of being controlled elasticity opening and closing by inner core nail 5, Cannulated hip screw 1 tail end has female thread 4; Drive-in inner core nail 5 is divided into the circular cone tip 8 of head end and the round bar portion 10 of tail end, tail end round bar portion 10 is provided with the external screw thread 6 matching with the female thread 4 of Cannulated hip screw 1, and on tail end cross section, is provided with the groove 7 in order to be connected with the head end of screwdriver and can to rotate thereupon.

Embodiment 2: referring to Fig. 1, Fig. 3, the inner core of the present embodiment nail adopts lift type inner core nail, comprises the spindle portion 9 of head end and the round bar portion 10 of tail end, is provided with the external screw thread matching with Cannulated hip screw 1 female thread in round bar portion 10.Other are with embodiment 1.

Referring to Fig. 1, 2, 3, fixing means of the present utility model is: except continuing to use traditional PFN fixing means and step, when adopting drive-in inner core pin, the head end of screwdriver is connected with the groove of drive-in inner core nail 3, rotation screw cutter makes drive-in inner core follow closely 3 round bar portion external screw threads along the mutual interlock rotation of female thread 4 of Cannulated hip screw 1, making circular cone tip 8 ecto-entads of drive-in inner core nail 3 advance gradually to enter in the thinner tube chamber in Cannulated hip screw 1 head end threaded portion 2 expands outwardly it, support is spongy bone around, significantly strengthen the hold of hip screw-bone interface, thereby reach the object that fixedly secures osteoporotic intertrochanteric fracture.When adopting lift type inner core nail, the spindle portion 9 of lift type inner core ailhead end is interior outwards to be lifted gradually to enter in the thinner tube chamber in Cannulated hip screw 1 head end threaded portion 2 it is expanded outwardly, and support is spongy bone around, significantly strengthens the hold of hip screw-bone interface.

Claims

1. the hip screw of a PFN, it is characterized in that: comprise Cannulated hip screw (1) and portion's inner core nail (5) movably within it, on described Cannulated hip screw (1) head end (2) tube wall, offer 2-6 longitudinally equidistant crack (3), form the longitudinal screw bar of being controlled elasticity opening and closing by inner core nail (5).

2. the hip screw of PFN as claimed in claim 1, is characterized in that: described Cannulated hip screw (1) head end (2) internal diameter is thin compared with bar portion internal diameter, and tail end is provided with female thread (4); The tail end of inner core nail (5) is provided with the external screw thread (6) matching with the female thread (4) of Cannulated hip screw (2) tail end.

3. the hip screw of PFN as claimed in claim 2, is characterized in that: the tail end cross section of described inner core nail (5) is provided with groove (7).

4. the hip screw of PFN as claimed in claim 1, is characterized in that: described inner core nail (5) comprises drive-in inner core nail and lift type inner core nail.

5. the hip screw of PFN as claimed in claim 4, it is characterized in that: described drive-in inner core nail comprises the circular cone tip (8) of head end and the round bar portion (10) of tail end, is provided with the external screw thread matching with Cannulated hip screw (1) female thread in round bar portion (10).

6. the hip screw of PFN as claimed in claim 4, it is characterized in that: described lift type inner core nail comprises the spindle portion (9) of head end and the round bar portion (10) of tail end, is provided with the external screw thread matching with Cannulated hip screw (1) female thread in round bar portion (10).