The Quality of Fracture Reduction with the Intra-Operative Use of the 3D-RX-System in fractures of the extremities

Despite the present surgical and technical knowledge, suboptimal fracture
reduction is still a major problem. For the ankle and foot an unsatisfactory
fracture reduction is reported after 18-26% of the operations. This may result
in severe functional damage of joints and posttraumatic arthrosis, pain, and
loss of function of the joint.
In order to achieve anatomical fracture reduction, an optimal view of
the position of the bone fragments and fixation material is a necessity. The
currently used 2D-fluoroscopy does not provide sufficient insight, in
particular in cases with complex anatomy or subtle injury. Postoperative X-ray
images or CT-scans frequently show anomalies (e.g. incongruences in the joint
surface or screws located intra-articularly), while these were not recognized
on the intra-operative 2D-fluoroscopic images.
Unfortunately logistical reasons and radiation dose restrict a CT-scan
to postoperative use only. Irregularities then found could lead to a new
operation. Recently the 3D-RX-system was developed, which provides conventional
2D-fluoroscopic images as well as a 3D-reconstruction of the bony structures.
Studies in Germany and our own hospital have already proven this modality
provides more information which consequently leads to extra corrections in 18-
32% of the fracture operations. However, the effect of the extra corrections on
the quality of the anatomical fracture reduction has never been investigated.

Objective of the study is to asses quality of fracture reduction and
patient-relevant outcomes with the intra-operative use of the 3D-RX-system as
compared to the conventional 2D-fluoroscopy in patients with traumatic
intra-articular fractures of the ankle, calcaneus or wrist. The second aim is
to assess the diagnostic value of the 3D-RX- images as compared the CT-scan as
reference standard. Also a cost-effectiveness analysis will be performed.

Multicenter randomised clinical trial.

In first instance only 2D-fluoroscopy is used for the intra-operative imaging,
as part of the usual intra-operative diagnostic procedure. The surgeon will
then operate until (s)he is satisfied with the fracture reduction and the
osteosynthesis. Randomization will determine whether or not the information of
the 3D-scan will be made available to the surgeon. If the 3D-scan results will
not be made available, the surgeon terminates the procedure. If the information
of the 3D-scan is available to the surgeon he can act on the findings and, if
necessary, surgical corrections can be made. If the surgeon is satisfied with
the operation result a conclusive 3D-RX-scan must be made. In both
randomization groups a CT-scan will be performed postoperatively.

All intra-operative images (both 2D-fluoroscopy and 3D-scans) and postoperative
CT-scans will be blinded and presented in random order for evaluation by 5
experts. During hospital stay the pain score (VAS-score) will be recorded
daily. The follow-up after hospital discharge will be at week 6, 12 and 26, 52
and after 2 and 5 years postoperatively. The range of motion and the
functional outcome will be recorded. For the ankle and foot the *Foot and Ankle
Outcome Score* (FAOS) will be used for this, for the wrist the *Disabilities of
Arm and Shoulder* (DASH) score will be used.

All included patients will be subjected to additional intra-operative 3D-RX. In
half of the patients the surgeon will be blinded to these results, in the other
half the surgeon may use the 3D-RX results to further optimize fracture
reduction.

- 1-2 intra-operative 3D-RX-scans
- A CT-scan of the ankle, calcaneus or wrist
- 2 extra X-rays after two and five years
- time investment in filling out questionnaires