A Study on Designing, Development and Testing of an Innovative External Jig for the Percutaneous Screw Fixation of the Acetabular Column Fractures

Abstract

Background: Operative treatment of acetabulum fractures often requires open surgical fixation. Minimally
invasive surgery (MIS) with percutaneous screw fixation can be done is some acetabular column fractures
which are amenable to closed reduction. This can be done free hand using intraoperative fluoroscopy or with
the help of advanced 3D navigation system. Free hand technique exposes the operative staff to considerable
intraoperative fluoroscopy,has a steep learning curve and there is a risk of screw malpositioning. Even
though 3D navigation is highly accurate, the affordability of the navigation system in a rural set up is not
feasible. Use of an external universal modular jig which has been routinely used for the fixation of long
bone fracture, can give similar results in the fixation of undisplaced/minimally displaced acetabular column
fractures amenable to close reduction. Currently such jigs are not available for the management of acetabular
fractures.
Objectives: With this study we aim to design a modular jig for the percutaneous fixation of the acetabular
column fracture fixation. Also we will validate in vitro efficacy and safety on cadaveric models. To test the
clinical efficacy on minimally displaced acetabular column fractures.
Methodology: It will be an observational study conducted at the Department of Orthopaedics, JNMC,
Sawangi and Wardha, India. A 3 D model of the pelvis will be made based on the CT scan data of 40
patients using Mimics 10.01 software (Materialize, Leuven, Belgium) software. After the desired jig is
made,its accuracy will be checked on the saw bone and cadaveric model. Once the accuracy of the jig has
been established, it will be used on the suitable patient population and the results will be compared with
the matched patient population who have been operated using the traditional free hand technique under
fluoroscopy control.
Results: The results will be compared based on the operating time,radiation exposure,hospital stay and
postoperative outcome. During follow up,patients in both the groups will be evaluated clinically with Harris hip score (HHS) and radiologically with
Matta outcome grading. To evaluate functional
outcome patients the patients will be categorized
into excellent (HHS, 90-100), good (HHS, 80-
90), fair (HHS, 70-80) and poor (HHS, <70).Conclusion: This study will help in designing and development of an universal external modular jig for the
MIS and percutaneous fixation of acetabular column fracture.