Objectives. Small animal models of fracture repair primarily investigate
indirect fracture healing via external callus formation. We present
the first described rat model of direct fracture healing. Methods. A rat tibial osteotomy was created and fixed with compression
plating similar to that used in patients. The procedure was evaluated
in 15 cadaver rats and then in vivo in ten Sprague-Dawley
rats. Controls had osteotomies stabilised with a uniaxial external
fixator that used the same surgical approach and relied on the same
number and diameter of
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
The use of two implants to manage concomitant ipsilateral femoral
shaft and proximal femoral fractures has been indicated, but no
studies address the relationship of dynamic hip screw (DHS) side
plate screws and the intramedullary nail where failure might occur
after union. This study compares different implant configurations
in order to investigate bridging the gap between the distal DHS
and tip of the intramedullary nail. A total of 29 left synthetic femora were tested in three groups:
1) gapped short nail (GSN); 2) unicortical short nail (USN), differing
from GSN by the use of two unicortical bridging screws; and 3) bicortical
long nail (BLN), with two angled bicortical and one unicortical bridging
screws. With these findings, five matched-pairs of cadaveric femora
were tested in two groups: 1) unicortical long nail (ULN), with
a longer nail than USN and three bridging unicortical screws; and
2) BLN. Specimens were axially loaded to 22.7 kg (50 lb), and internally
rotated 90°/sec until failure.Objectives
Methods
