CN2487349Y - Pressing expansion screw with locking for neck of femur - Google Patents

Abstract

The utility model relates to a medical apparatus, in particular to a pressing expansion screw with locking for neck of femur. The utility model is characterized in that: a front axis of main nail is separately provided with a straight slot along the two sides, the straight slot is communicated with an axis hole, the rear end of the main nail which is at the same side as the straight slot is provided with an oblique keyhole which forms an angle more than 90 degrees with the axis direction, the bifurcate nail of femur head is arranged inside the main nail; the oblique locking nail is arranged inside the oblique keyhole. Through improvement, the utility model is provided with more reliability and more firmly inner locking, the utility model can effectively antagonize the separation of broken ends of fracture, shearing torsion and stress force, which is convenient for patient to early get out of bed and is also convenient to cicatrization of fracture. The utility model has the advantages of more easy and convenient operation, easy mastery and shorter operation time.

Description

Neck of femur expansion type forcing screw with lock

This utility model relates to a kind of medical apparatus, specifically the neck of femur internal fixation screw.

Fracture of femoral neck is comparatively common, and disunion or delayed union easily take place its fracture.Strong internal fixation is particularly important.Can reduce the chance that fracture complication takes place.The fracture of femoral neck internal fixation material is more, be pinned to nearest Richards nail, hook nail-compression screw, hollow double end forcing screw, mother and sons' nail and power forcing screw etc. from originally three wing nail, Pugh nail, Knowles, but all there is the clinical weak point that is difficult to overcome of orthopaedics, because the restriction in neck of femur sectional area and the technical operation, many nails fixedly are difficult to the central authorities of stress concentration in neck of femur, many nails in the design even often have place the outer situation of neck, do not reach fixation effectively.In addition, remain at screw loosening, fracture, between most advanced and sophisticated break-through femoral head, the broken ends of fractured bone a little less than compression strength and shearing resistance, the torsional rotation force amount, problems such as big, the complicated operation of wound.

This utility model is at the deficiencies in the prior art, provide a kind of separation, shearing that can effectively resist between fracture site to reverse and stress, the far and near end of fracture is synchronized with the movement, keep its relative stability, help the neck of femur expansion type forcing screw with lock of patient's early ambulant and union of fracture.

The technical pattern scheme is so particularly:

Neck of femur expansion type forcing screw with lock comprises main nail, femoral head forked nail, oblique pinning and the even power pad of pressurization nut etc., it is characterized in that:

(1), master's nail front portion is the spongy bone tapping screw thread, afterbody is regular screw threads, the middle part is threadless polished rod, expand slightly the self-locking hole front, main nail axially has a through hole forward by afterbody, its front axle has the in-line groove to both sides, in-line groove and axis hole connect, with the main nail rear portion of in-line groove homonymy have one with the axial oblique lockhole that becomes greater than an angle of 90 degrees, main nail tail end has the rectangle bayonet socket, there is the screw thread that advances nut to be screwed into for forked nail at the middle part to afterbody in the axial hole, main nail middle part, and front end has the duct that can pack into guide pin;

(2), the femoral head forked nail is short forked nail, front portion be forked section, there is the nut that expands at the middle part controlling the direction that enters in the main nail, the rear portion has and connects the screw thread that advances handle, the femoral head forked nail is located in the master follows closely;

(3), oblique pinning is located in the oblique lockhole.

This utility model has more reliable, stronger internal fixation by improving, and can effectively resist separation, the shear stress between fracture site and reverses, in order to patient's ground and union of fracture down in early days.Bigger by improving this nail compression strength, wound is littler; This utility model only needs an axle center to advance nail, the external nail situation of neck can not occur; Screw loosening can not occur, withdraw from and the capital situation of most advanced and sophisticated break-through; The broken nail situation can not appear.Use this utility model, operate easylier, be easy to grasp, operating time is shorter.

Fig. 1 is this utility model structural representation,

Fig. 2 is screw assembling sketch map.

Below in conjunction with accompanying drawing, the utility model is further described.

This neck of femur expansion type forcing screw with lock comprises that main nail 1, femoral head forked nail 2, forked nail advance nut 3, even power pad 4, pressurization nut 5, oblique pinning 6 and main nail tail medicated cap.

Main nail 1 front portion is the spongy bone tapping screw thread, afterbody is regular screw threads, the middle part is threadless polished rod, expand slightly the self-locking hole front, main nail 1 axially has a through hole forward by afterbody, its front axle has the in-line groove to both sides, in-line groove and axis hole connect, with the main nail rear portion of in-line groove homonymy have one with the oblique lockhole that axially is greater than an angle of 90 degrees, main nail 1 tail end has the rectangle bayonet socket, there is the screw thread that advances nut 3 to be screwed into for forked nail at the middle part to afterbody in the main nail axial hole, 1 middle part, and front end has the duct that can pack into guide pin.

Femoral head forked nail 2 is the weak point forked nail, and the front portion is a forked section, and there is the nut that expands at the middle part to control the direction that enters in the main nail 1, and there is the screw thread that connects the propelling handle at the rear portion, and femoral head forked nail 2 can be plugged in the main nail 1.

Oblique pinning 6 is inserted in the oblique lockhole of main nail 1.

Even power pad 4 is wide at the top and narrow at the bottom, and lateral surface is smooth and perpendicular to main nail, inner face except that on have a down dip and still have one and the arc-shaped concave that matches of bone convex surface.

Specific operation process is as follows: electricity is inwardly gone up with femoral shaft down from greater trochanter down thoroughly and is become 135 to spend angles, positive side position is all advanced a Kirschner wire by neck of femur mediad femoral head and is guided, clear the way to subchondral bone along guide pin with reamer, main nail 1 with designated length, overlapping guide pin screws in, to the subchondral bone below, and make terminal bayonet socket facing to fore-and-aft direction, the femoral head forked nail 2 of packing into, be screwed into and advance nut 3, make forked nail 2 abundant bifurcateds, load onto the even power pad 4 of pressurization nut at main nail tail end, rotation pressurization nut 5 fully pressurizes, make the fracture site fluid-tight engagement, oblique pinning sight is installed, on sclerotin, punch by oblique lockhole with the long drill bit identical with the pinning diameter, pack into oblique pinning and tightening, the main nail tail medicated cap 7 of screwing at last.

The use of forked nail 2 further strengthens the pulling force effect, and the pressurization in conjunction with pressurization nut 5 makes the fracture line adequate closure.Femoral head forked nail 2 and pinning 6 be with being connected by main nail 1, make fracture far and near hold in aggregates, be synchronized with the movement, and do not influence its relative stability.The use of oblique pinning 6 can resist the shearing strength of fracture effectively.Because being 135 degree angles with femoral shaft, main nail 1 enters, the pressurization nut can't evenly push on femoral cortex, be spongy bone owing to entering to follow closely the position simultaneously, this certainly will cause the nut below to imbed cortical bone, and top contact bone cortex not as yet, the effect of even power pad 4 promptly is that the pressure of pressurization nut 5 is evenly arrived on the cortical bone by the conduction of even power pad 4.

Claims (1)

1, neck of femur expansion type forcing screw with lock comprises main nail, femoral head forked nail, oblique pinning and the even power pad of pressurization nut etc., it is characterized in that:

(1), master's nail front portion is the spongy bone tapping screw thread, afterbody is regular screw threads, the middle part is threadless polished rod, expand slightly the self-locking hole front, main nail axially has a through hole forward by afterbody, its front axle has the in-line groove to both sides, in-line groove and axis hole connect, with the main nail rear portion of in-line groove homonymy have one with the axial oblique lockhole that becomes greater than an angle of 90 degrees, main nail tail end has the rectangle bayonet socket, there is the screw thread that advances nut to be screwed into for forked nail at the middle part to afterbody in the axial hole, main nail middle part, and front end has the duct that can pack into guide pin;

(2), the femoral head forked nail is short forked nail, front portion be forked section, there is the nut that expands at the middle part controlling the direction that enters in the main nail, the rear portion has and connects the screw thread that advances handle, the femoral head forked nail is located in the master follows closely;

(3), oblique pinning is located in the oblique lockhole.

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