Executive Editor: Jörg Auer

Authors: Jörg Auer

Phalanges Distal phanlanx, Abaxial articular

back to skeleton

Glossary

Screw fixation
Main indication Skill Equipment
Return to athletic function Highly experienced and skilled surgeon Full specialized surgical and imaging resources


Availability of pre- and intraoperative advanced diagnostic imaging techniques are a prerequisite for internal fixation of the fracture by means of screws inserted in lag technique.
Pre- and intraoperative CT imaging and computer assisted surgery allow exact determination of the screw direction to achieve maximum purchase of the fragment and prevent inadvertent penetration of the sole or the joint.
These techniques also allow determination of the distance to the fracture plane and the screw length needed.



An alternate technique represents computer-assisted surgery, which is presently rarely available.

This technique involves initial CT- or 3-D fluoroscopic (A,B) imaging data of the involved bone identified with a digital reference base (DRB), transfer of the data to the navigation computer (C), planning of screw location, -orientation and –length with the help of a mouse on the navigation computer screen, and real time navigational assistance during screw insertion (see below).
The camera (D) provides real-time navigation assistance.



A screen shot during preparation of the thread hole in an abaxial fracture of the distal phalanx.
Three different orthogonal views are shown. The red bar represents the planned direction for a 4.5 mm screw, whereas the green bar represents the 3.2 mm drill bit entering the glide hole already prepared up to the fracture pane. The drill bit has penetrated the glide hole for 19.4 mm (see picture bottom right).
Note: the two bars are represented in correct scale relative to their diameter.
The axial trajectory view represents the perfect alignment of the drill (yellow circle), the planned screw diameter (red circle), and the drill bit (green circle.)
Note: the sizes of the circles are not proportional to their diameter in this projection.



If these techniques are not available, conservative treatment – as described for the abaxial fractures without joint involvement should be selected.

*Skill
Basic surgical experience, no specialized skills Basic surgical experience, no specialized skills
Some specialized surgical experience Some specialized surgical experience
Highly experienced and skilled surgeon Highly experienced and skilled surgeon
*Equipment
Basic equipment only Basic equipment only
Simple surgical and imaging resources Simple surgical and imaging resources
Full specialized surgical and imaging resources Full specialized surgical and imaging resources

v1.3 2013-11-20