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Stem cell-powered PEEK Orthopedic Implant For Strength and Longevity

September 30, 2012 by Leave a Comment

Procedures such as hip replacement surgeries are able to restore mobility to people and are currently made of polyethylene, stainless steel, titanium or ceramic.

Each material has its own issues like biocompatability issues and inflexibility and  over the years wear and tear demands replacement of the implant.

Researchers as the University of Glasgow in collaboration with surgeons at Glasgow’s Southern General Hospital are developing a new type of orthopaedic implant that is likely to be considerably stronger and more long-lived than present products. [Read more...]

Filed Under: Implants-Instruments, Joint Replacement, News Tagged With: , ,

Clinical Photograph of Tibia Showing Backed Out and Exposed Screws

September 16, 2012 by Leave a Comment

34 years old female with history of being operated for fracture tibia about 10 years back.  A dynamic compression plating was done and fracture united eventually.

She came with a complaint of exposed screw. Examination of the part revealed following picture.

Exposed Screw From Tibial Plate

Exposed Screw From Tibial Plate

Please note that there is an exposed screw clearly visible. In addition, there is a screw that is tenting on the skin.

Filed Under: Images, Implants-Instruments, Leg Injuries, Radiology Tagged With: , , ,

Broken Fixed Angle Blade Plate In Intertrochanteric Fracture

December 27, 2011 by Leave a Comment

The following xray [no actual patient information could be found with this file] shows a broken fixed angle blade plate in a case of intertrochanteric fracture.

Broken Angle blade plate after hip surgery

Broken Angle Blade Plate After Hip Surgery

Probably, the fixed angle blade plate was done as a revision surgery because there are broken screws in addition to screws that are holding the plate.

There was no patient information attached with this file.

Note Fixed angle blade plate was extensively used earlier for treatment of intertrochanteric fractures but with better gadgets available now, it is rarely used.

Filed Under: Hip Injuries, Implants-Instruments Tagged With: , ,

What Is Herbert Screw?

December 15, 2011 by 1 Comment

A Herbert screw is a special purpose screw used to compress small fractures fragments. One of the unique feature of the screw is that it is threaded on the both sides. It is also called headless screw.

The screw was invented by Timothy Herbert.

Herbert Screw
Herbert Screw

One end of the screw has cancellous threads while the other end has larger diameter cortical screw threads. The cancellous screw is inserted first and crosses the proximal fracture, screwing into the bone of the distal fragment. As it is screwed in, the proximal cortical portion engages the proximal bone fragment.

Herbert screws are especially useful in articular fractures and small bones like scaphoid.

Because of difference in the pitch and the size of the threads, Each turn of the screw causes the distal end to travel farther into bone than the proximal end resulting in compression of the fracture.

Filed Under: Definitions, E-H, Implants-Instruments Tagged With: , , ,

AP and Lateral Xrays of Fracture Capitellum and Medial Epicondyle Humerus Fixed With Screws

December 14, 2011 by Leave a Comment

Fracture capitellum in left upper limb of a  34 years male was operated using Herbert Screws[Headless Screws]. Associated fracture of medial epicondyle was fixed with a cancellous screw.

Here are the postoperative xrays.

First the AP view

Fracture Capitellum and Medial Epicondyle Humerus Fixed With Herbert and Cancellous Screws.

Fracture Capitellum and Medial Epicondyle Humerus Fixed With Herbert and Cancellous Screws - Anteroposterior View

The lateral view given below was taken at different interval, probably in immediate postoperative period as you can see the plaster as well. [Read more...]

Filed Under: Elbow Injuries, Images, Implants-Instruments, Radiology Tagged With: , , , , ,

Photographs of Acteabular Cup With Cement Removed In Revision Arthroplasty

June 21, 2011 by Leave a Comment

46 years old adult male presented with dislocation of the prosthesis after total hip arthroplasty surgery. His xray revealed a acetabular cup in unacceptable position and thus a revision of acetabular cup was done.

Following images are of the removed acetabular cup from previous surgery.

Acetabular-Cup WIth Excess Cement
Note the excessive cement present. [Read more...]

Filed Under: Hip Replacement, Implants-Instruments, Joint Replacement Tagged With: , , , , ,

What Is Interfragmentary Screw or Lag Screw

February 14, 2011 by 2 Comments

Interfragmentary screw or lag screw is used in fixation of spiral or oblique fractures of the shaft of a bone. Interfragmentary screw or lag screw is used as an adjunct to plating and often as initial fixation holder so as to safe and secure application of plate in neutral mode in reduced fracture.

The procedure involves  placement of one or more screws across a fracture site so that fractured fragments are apposed and compressed to each other, called interfragmentary compression ( See image below). The interfragmentary screw can also be used for fixation after osteotomies. [Read more...]

Filed Under: Definitions, I-M, Implants-Instruments Tagged With: , , , , , ,

Kirschner Wire or K Wire

January 13, 2010 by Leave a Comment

Kirschner wires or K wires were invented by Martin Kirschner in 1909. They have a great role in management of orthopedic trauma and correction of deformities.

They  are  sharpened, smooth stainless steel pins which are available in different diameters and lengths.

They are used both in surgical and conservative management of fractures. In surgery they are either used to hold the fracture fragments temporarily before definitive implant is put or are used as for definitive treatment o fractures too. [Read more...]

Filed Under: Implants-Instruments Tagged With: , , , , , ,

Fracture Proximal Phalanges Fixed With K Wire

January 9, 2010 by Leave a Comment

K wire is the short term for Kirchner Wire.

K wire is frequently used in treatment of fractures in children and in hand injuries among other things.

The xray below is post operative image of a 26 years old labroure who injured his hand due to work related injury.

He suffered from fracture of proximal phalanx of second and third digit.

The injury was treated with closed reduction and K wire fixation under C Arm.

The fracture has united after 4 weeks and patient has been put on mobilization exerecises.

Filed Under: Hand Injuries, Images, Implants-Instruments, Radiology Tagged With: , , , ,

Fracture Humerus Fixed Plates and Screws With Radiological Signs of Implant Loosening

January 7, 2010 by 4 Comments

If after fixation of a fracture, there is failure to unite within certain amount of time, there is danger of implant getting failed.

With improved qualities of implants, meticulous surgical techniques and careful postoperative protocols, the failures can be reduced.

But still failures do occur.

After a fracture is fixed there is kind of race between fracture union and implant fatigue. Fatigue is the progressive and localized structural damage that occurs in materials when a material is subjected to cyclic loading.

In other words every time an implant is subjected to stress, there occurs a damage to it. Repetitive damage accumulates over the periods and ultimately leads to breakage of the implant.

This is one kind of fixation failure. [Read more...]

Filed Under: Humerus Fractures, Implants-Instruments Tagged With: , , , , , ,