In 20 patients,
a fracture seen on conventional radiographs is confirmed upon CBCT.
In 33 out of 89 patients (i.e.
in 37 %) who were initially scored negative on radiographs,
at least 1 carpal fracture was detected on CBCT (16 scaphoid,
5 hamulus of the hamate,
5 trapezium,
and one capitate,
one lunate ,
one hamate,
one trapezoid,
and in 3 patients a combination of lunate,
capitate trapezium,
triquetral,
or hamate fractures).
Thus,
using CBCT,
37 fractures were detected in this subgroup initially being interpreted radiographically negative.
Sixteen out of these (i.e.
18 % of initially misdiagnosed fractures) were scaphoid fractures,
representing so-called "occult" scaphoid fractures (Figs.
1-5).
Besides detection of these fractures,
CBCT furthermore enabled to install correct treatment as a function of fracture type; as acute fractures of the distal scaphoid pole and tubercle are treated conservatively with casting,
whereas nondisplaced acute waist fractures may be treated with a short or long arm cast or operatively,
and on the contrary ,-likewise displaced scaphoid waist fractures-,
proximal pole fractures are typically treated surgically,
CBCT afforded to choose prompt optimal treatment in these 16 patients with occult scaphoid fractures.
If not being examined with CBCT,
all of these 89 patients would have undergone standard conservative treatment with casting and repeat radiographs in two weeks.
This procedure however would have implied an unnecessary temporarily immobilization in 56 out of these 89 patients with potential negative impact on professional activities and daily life.
The same holds true in 27 out of 30 cases where radiographs were equivocal in whom CBCT could exclude a wrist fracture (i.e.
in 90 %).
Only in three out of these 30 patients,
a fracture of the trapezium and scaphoid was found upon CBCT in respectively one and two cases,
thereby enabling adequate treatment in these,
but avoiding unneccesary casting and follow-up in 27 other patients (Figs.6-11).