- Discussion:
- available in sizes from 80 mm to 240 mm (most adults require 150 to 160 mm rings for the tibia);
- rings should be large enough to allow at least 2-3 cm of space between the
ring and skin (inorder to avoid pressure ulcerations);
- most often the ring and skin will come into contact posteriorly;
- rings that are too large will not support transfixing wires adequately,
and osteogenesis will be impaired;
- two rings are used on large fragments, & ring and drop post used for
smaller fragments;
- most proximal ring in tibial mounting can be an open section ring in
tibial mounting can be an open section ring attached to a complete
ring, allowing maximum flexion & providing two levels of fixation;
- Ring Components:
- composite half rings
- half rings
- half rings with curved extremities
- 5/8 half rings
- foot rings;
- Ring Components:
- threaded and telescopic rods;
-
rancho cubes:
- allow attachment of 4.0, 5.0, or 6.0 mm
half pins to the ring;
- require use of centering sleeves between cubes and
half pins;
- hexagonal set screws fit thru threaded extremity holes to lock centering sleeves;
- rancho drill guide and trocar are used to direct drill bits thru cubes;
-
connection plate:
- allows rings of different diameters to be connected;
- special buckles are available to better secure a plate to a ring (rather that using
standard bolts)
-
posts:
- are used for attaching "drop wires" to the ring;
- are used for insertion of oblique half pins;
-
paired conical washers:
- these help compensate for a connecting rod's obliquity to the frame;
