Abstract
Objective The aim of this study was to evaluate the accuracy of patient-specific three-dimensional
printed drill guides (3D-PDG) for the placement of a coxofemoral toggle via a minimally
invasive approach.
Materials and Methods Pre-procedure computed tomography (CT) data of 19 canine cadaveric hips were used
to design a cadaver-specific 3D-PDG that conformed to the proximal femur. Femoral
and acetabular bone tunnels were drilled through the 3D-PDG, and a coxofemoral toggle
pin was placed. The accuracy of tunnel placement was evaluated with post-procedure
CT and gross dissection.
Results Coxofemoral toggle pins were successfully placed in all dogs. Mean exit point translation
at the fovea capitis was 2.5 mm (0.2–7.5) when comparing pre- and post-procedure CT
scans. Gross dissection revealed the bone tunnel exited the fovea capitis inside (3/19),
partially inside (12/19) and outside of (4/19) the ligament of the head of the femur.
Placement of the bone tunnel through the acetabulum was inside (16/19), partially
inside (1/19) and outside (2/19) of the acetabular fossa. Small 1 to 2 mm articular
cartilage fragments were noted in 10 of 19 specimens.
Clinical Significance Three-dimensional printed drill guide designed for coxofemoral toggle pin application
is feasible. Errors are attributed to surgical execution and identification of the
borders of the fovea capitis on CT data. Future studies should investigate modifications
to 3D-PDG design and methods. Three-dimensional printed drill guide for coxofemoral
toggle pin placement warrants consideration for use in select clinical cases of traumatic
coxofemoral luxation.
Keywords
coxofemoral luxation - toggle pin - dog - three-dimensional printed drill guide -
minimally invasive
