An
out line on the design and rationale of the nail plate device
for stabilising a periprosthetic fracture of distal femur in total knee
replacement-
Dr. Jacob Varughese
Displaced supracondylar fractures (type 2) needs to be properly
aligned and stabilized for an optimal outcome. Stabilization using
intramedullary nails, locking plates, external fixators have been
described. The small porotic distal fragment precludes stable fixation with either plate or nail to commence immediate mobilisation.
Design of a nail plate device
In 2009 following
difficulty in stabilising these distal femoral fractures combination of a separate Intra medullary nail and a locking plate was used to stabilise and mobilise the elderly
above mentioned osteoporotic fracture.
This was repeated in bilateral case where in the nail was
removed to pass the distal locking
screws from the plate resulting in
translation of the distal fragment ref
pic 4 below. Both the fractures healed in 3 months and the
patient was mobilised weigth bearing
Procedure
Knee replacement
incision.
A supracondylar nail 9 mm in diameter was passed through the distal
fragment and using this to reduce the
fragment and pass it retrograde into the proximal fragment. This avoids soft
tissue stripping and quick reduction of the fracture in anterior-posterior and
medial lateral planes with out soft
tissue stripping associated with reduction with a plate device. This nail
devise could be locked proximally and distally if possible or at this stage a
locking plate is passed through a MIPPO technique on the lateral side and
locking screws can be applied distally though the incision and percutaneous
screws can be applied proximally. In the case
in picture 3 on the right knee the nail was removed after the plate was
applied distally to facilitate screw
insertion resulting in translation in the medio-lateral plane. Therefore it was
decided to use both nail and plate in 3 further cases where in we obtained
stable reduction to facilitate immediate mobilisation.
With these results we attempted to design a
new implant ( nail plate device) to improve the technique and rigidity of fixation
