There is not adequate evidence to establish whether external
fixation (EF) of pelvic fractures leads to a reduced mortality.
We used the Japan Trauma Data Bank database to identify isolated
unstable pelvic ring fractures to exclude the possibility of blood
loss from other injuries, and analyzed the effectiveness of EF on
mortality in this group of patients. This was a registry-based comparison of 1163 patients who had
been treated for an isolated unstable pelvic ring fracture with
(386 patients) or without (777 patients) EF. An isolated pelvic
ring fracture was defined by an Abbreviated Injury Score (AIS) for
other injuries of <
3. An unstable pelvic ring fracture was defined
as having an AIS ≥ 4. The primary outcome of this study was mortality.
A subgroup analysis was carried out for patients who required blood
transfusion within 24 hours of arrival in the Emergency Department
and those who had massive blood loss (AIS code: 852610.5). Propensity-score
matching was used to identify a cohort like the EF and non-EF groups.Aim
Patients and Methods
We evaluated the effect of low-intensity pulsed ultrasound stimulation (LIPUS) on the remodelling of callus in a rabbit gap-healing model by bone morphometric analyses using three-dimensional quantitative micro-CT. A tibial osteotomy with a 2 mm gap was immobilised by rigid external fixation and LIPUS was applied using active translucent devices. A control group had sham inactive transducers applied. A region of interest of micro-CT was set at the centre of the osteotomy gap with a width of 1 mm. The morphometric parameters used for evaluation were the volume of mineralised callus (BV) and the volumetric bone mineral density of mineralised tissue (mBMD). The whole region of interest was measured and subdivided into three zones as follows: the periosteal callus zone (external), the medullary callus zone (endosteal) and the cortical gap zone (intercortical). The BV and mBMD were measured for each zone. In the endosteal area, there was a significant increase in the density of newly formed callus which was subsequently diminished by bone resorption that overwhelmed bone formation in this area as the intramedullary canal was restored. In the intercortical area, LIPUS was considered to enhance bone formation throughout the period of observation. These findings indicate that LIPUS could shorten the time required for remodelling and enhance the mineralisation of callus.
