A four-sided solid titanium 6% aluminium 4% vanadium alloy nail, diameter of 12.5mm and with 4.6mm holes spaced at 1 5mm intervals, has been designed and extensively tested since 1967. Titanium screws, inserted with the aid of a special jig, fix both cortices of the femur as well as the nail, and hold the femur rigidly to the nail. Three or four 4.5mm titanium screws re used below, and the same number above, the fracture site.
One end of the nail has four oblique holes at 1300 for use with 4.5mm lag screws up the femoral neck and into the head, for combined fractures of the hip and femoral shaft. Nails with all transverse holes are also available, with all types of nail being bullet tipped.
The nail has an advantage in being designed for difficult fractures of the entire shaft of the femur, including comminuted fractures and combined fractures of the hip and shaft. The femur may also be lengthened over the nail using bone graft.
A 10.5mm diameter nail is available for the tibia or humerus, and an 11.5mm nail for the smaller femur. Various lengths of nail are also available to accommodate most indications however alternative lengths are available to special order. No X-ray control or special operating table is required, except in closed nailing or where there is an associated fracture of the hip where screws need to be inserted up the femoral neck.
ADVANTAGES
Ability to compress fractures and hold rotation with screws, transfixing both cortices of the bone and nail.
Oblique 4.6mm holes in one end in the standard nail, allow for 4.5mm compression screws up the neck of the femur.
Nail does not usually require removal.
Top of nail recessed in trochanter.
Minimal reaming to 13mm for 12.5mm nail.
Square cross section allows for medullary blood supply to regenerate.
Completely biocompatible.
Modulus of elasticity half that of stainless steel and chrome cobalt.
Stronger than most other implants with symmetrical cortical compression obtained with the nail and screws.
Three diameters of nail available.
Unique jig makes X-ray control or special operating table for shaft fractures unnecessary.
Nail (12.5mm) is 1.1 to 1.8 times stronger than the average femoral shaft with three screws equal to strength of nail.
Ability to be full weight-bearing immediately postoperatively in most cases.
Union usually in 2-6 months, even in previously established non-union.
{{{ OPERATING TECHNIQUE WILL BE SENT IN NEXT BLOG}}}
No comments:
Post a Comment