3.5 Locking Attachment Plate
The 3.5 Locking Attachment Plate is indicated for use with locking compression plates (LCPs) to augment the stabilization of fractures, including periprosthetic fractures and fractures in the presence of intramedullary implants in the femur, tibia, and humerus, particularly in osteopenic bone.
Periprosthetic fractures are increasing because of the aging of the population, more active old people, the development of endoprosthetics and an increase in the number of patients with long-standing implants. The incidence has been reported to be 1.5% for primary procedures and 4% for revisions . Because of the prosthesis stem (or a nail) in the intramedullary canal it is not possible to insert screws bicortically as it would be needed. These fractures are mainly treated with cable systems and monocortical screws with the disadvantage of high invasiveness and the possibility of cutting into osteoporotic bone.
The 3.5 Locking Attachment Plate which can be attached to an LCP offers an alternative to cables (Fig 1). With the possibility to insert 3.5 mm locking screws bicortically by avoiding the prosthesis stem (Fig 2) a similar or even better mechanical stability than with cables can be reached with a less invasive procedure. The plate is attached to a base plate, in essence, widening that plate and its screw angle options to gain 3.5 mm screw purchase around a prosthesis or any device that may be blocking the intramedullary canal.
If necessary the plate can be adapted onto the bone shape. If the bone diameter is small, the plate can be bent, and screw angulations increased for the screws to get hold in the cortex.
The plate is simple to use and the decision can be made intraoperatively (implants are available, both nonsterile and sterile packed). The threaded insert portion of the connecting screw is inserted into the base plate. Then the plate is placed on top and locked with the upper portion of the connecting screw.
The 3.5 Locking Attachment Plate can also be used to prevent lateral screw pull-out in osteoporotic bone irrespective of a prosthesis or an intramedullary implant.
Old AB, McGrory BJ, White RR, et al Fixation of Vancouver B1 Periprosthetic fractures by broad metal plates without the application of strut allografts. J Bone Joint Surg Br. 2006; 88(11): 1425-1429.
Case provided by Klaus-Dieter Schaser, Berlin, Germany
Case 1: A 78-year-old female sustained a periprosthetic fracture, Vancouver type C, 9 years after a total hip arthroplasty.
Case provided by Michael Wagner, Wien, Austria.
Case 2: A 76-year-old female with a Vancouver type C fracture.
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