Sat., 10/6/12 Femur/Tibial Fx/Knee Injuries, PAPER #70, 8:12 am OTA-2012
Δ Radiographic Outcomes of Closed Diaphyseal Femur Fractures Treated With the SIGN Nail
Sasha P. Carsen, MD; Si-Hyeong Park, MD; David A. Simon, MD; Robert J. Feibel, MD;
University of Ottawa/The Ottawa Hospital, Ottawa, Ontario, Canada
Purpose: The burden of orthopaedic trauma in the developing world is significant and disproportionate, both in health and economic terms. The Surgical Implant Generation Network (SIGN) has developed and made available through donation to surgeons in resource- limited settings an intramedullary prosthesis for use in the treatment of fractures of the femur and the tibia, with the prosthesis and all necessary tools donated. Despite the great clinical success of the SIGN Nail, with more than 70,000 surgeries performed, there has been very little research examining outcomes. Our primary purpose was to examine the postoperative radiographs of closed diaphyseal femur fractures treated with the SIGN Nail to assess for alignment, and to evaluate variables for risk of malalignment. Our secondary goal was to assess the functionality and robustness of data in the SIGN database.
Methods: A retrospective review of SIGN’s prospectively populated database was performed for patients treated with the standard SIGN Nail for a diaphyseal femur fracture, which at the time of the study totaled 32,362. Exclusion criteria included open fractures and those without postoperative radiographs. A random number generator was used to randomly select 500 cases for analysis, and the following information was recorded: location of the fracture within the diaphysis, fracture classification (AO/OTA classification), degree of fragmentation (Winquist classification), time from injury to surgery, and patient demographics. Measurements of alignment were then made based on the AP and lateral radiographs, with malalignment defined conservatively as deformity in either the sagittal or coronal plane >5°. Measurements were made manually using on-screen protractor software (Screen Protractor, by Iconico), and intra- and interobserver reliability assessed. The quality of radiographs for each case was graded based on adequacy for visualization of the fracture and the femur, and the ability to measure alignment in orthogonal planes.
Results: The incidence of malalignment in postoperative radiographs was found to be 10.3%, with malalignment defined as deformity in either the sagittal or coronal plane >5°. 92% of reviewed radiographs were of acceptable or good quality. Fracture location in the proximal or distal diaphysis was strongly correlated to risk of mal-alignment (P <0.01). Time from injury to surgery of >4 weeks was also strongly correlated to risk of malalignment (P <0.01). Degree of fragmentation was found to be an independent predictor of angulation and malalignment (P = 0.07).
Conclusion: The incidence of malalignment in femoral fractures treated with the SIGN Nail closely approximated the incidence previously reported in the literature for a North American trauma center. This is an encouraging finding, and provides support for the continued and expanded use of the SIGN prosthesis throughout the developing world. Risk factors for malalignment include: fractures of the proximal or distal diaphysis; fractures with increased fragmentation; and, of note, fractures waiting >4 weeks for surgery. In addition, the SIGN database, which is populated by data submitted by SIGN surgeons around the world, was found to be a satisfactory resource for the purpose of retrospective research.
Δ OTA Grant
Alphabetical Disclosure Listing (808K PDF)
• The FDA has not cleared this drug and/or medical device for the use described in this presentation (i.e., the drug or medical device is being discussed for an “off label” use). ◆FDA information not available at time of printing. Δ OTA Grant.