External fixators are the traditional fixation method of choice for contaminated open fractures. However, patient acceptance is low due to the high profile and therefore physical burden of the constructs. An externalised locking compression plate is a low profile alternative. However, the biomechanical differences have not been assessed. The objective of this study was to evaluate the axial and torsional stiffness of the externalised titanium locking compression plate (ET-LCP), the externalised stainless steel locking compression plate (ESS-LCP) and the unilateral external fixator (UEF). A fracture gap model was created to simulate comminuted mid-shaft tibia fractures using synthetic composite bones. Fifteen constructs were stabilised with ET-LCP, ESS-LCP or UEF (five constructs each). The constructs were loaded under both axial and torsional directions to determine construct stiffness.Objectives
Methods
One commonly used rat fracture model for bone and mineral research
is a closed mid-shaft femur fracture as described by Bonnarens in
1984. Initially, this model was believed to create very reproducible
fractures. However, there have been frequent reports of comminution
and varying rates of complication. Given the importance of precise
anticipation of those characteristics in laboratory research, we
aimed to precisely estimate the rate of comminution, its importance and
its effect on the amount of soft callus created. Furthermore, we
aimed to precisely report the rate of complications such as death
and infection. We tested a rat model of femoral fracture on 84 rats based on
Bonnarens’ original description. We used a proximal approach with
trochanterotomy to insert the pin, a drop tower to create the fracture
and a high-resolution fluoroscopic imager to detect the comminution.
We weighed the soft callus on day seven and compared the soft callus
parameters with the comminution status.Objectives
Methods
Neurogenic heterotopic ossification (NHO) is
a disorder of aberrant bone formation affecting one in five patients sustaining
a spinal cord injury or traumatic brain injury. Ectopic bone forms
around joints in characteristic patterns, causing pain and limiting
movement especially around the hip and elbow. Clinical sequelae
of neurogenic heterotopic ossification include urinary tract infection,
pressure injuries, pneumonia and poor hygiene, making early diagnosis
and treatment clinically compelling. However, diagnosis remains
difficult with more investigation needed. Our pathophysiological
understanding stems from mechanisms of basic bone formation enhanced
by evidence of systemic influences from circulating humor factors
and perhaps neurological ones. This increasing understanding guides
our implementation of current prophylaxis and treatment including
the use of non-steroidal anti-inflammatory drugs, bisphosphonates,
radiation therapy and surgery and, importantly, should direct future, more
effective ones.
