Sat., 10/10/09 Knee/Tibia, Paper #80, 3:46 pm OTA-2009
A Direct Comparison of Union and Implant Failure Rates between the Stainless Steel and Titanium Less Invasive Stabilization System (LISS) for Distal Femoral Fractures
Saam Morshed, MD1 (7-Synthes); Michael J Gardner, MD2 (5A-Synthes, Expanding
Orthopedics; 7-AO, Synthes, Smith &Nephew);
David Barei, MD1 (4-AO, Smith &Nephew, Synthes, Zimmer; 7-Synthes, Zimmer);
Sean Nork, MD1 (7-AO, Synthes, Smith &Nephew, Stryker, Zimmer);
Daphne Beingessner, MD1 (7-AO, Synthes, Zimmer);
1Harborview Medical Center, Seattle, Washington, USA;
2Washington University School of Medicine, Saint Louis, Missouri, USA
Purpose: Locked plating has become one of the most common methods for treatment of supracondylar distal femur fractures. While numerous titanium and stainless steel implants are available, assessment of the effect attributable to metallurgy on clinical outcomes has been limited. We compared clinical outcomes for subjects treated with stainless steel and titanium versions of the LISS for distal femoral fractures.
Methods: All adult patients treated for a supracondylar femur fractures (OTA 33A and 33C) with the LISS at a single academic Level 1 trauma center were considered for inclusion. Subjects without a minimum follow-up of 6 months were excluded. Between 2003 and 2006, the titanium LISS was used, after which time an abrupt change was made to the use of the stainless steel version of this implant with similar geometry and screw configuration. Demographic, injury-specific, and technical factors were summarized and univariable and multivariable regression analysis were used to identify predictors of nonunion, implant failure, and the need for reoperation.
Results: 104 fractures were included in this study; 79 were treated with the titanium LISS and 25 with stainless steel. The mean follow-up was 10.7 months. The mean age was 50.7 years, and 59% of subjects were men. Patterns of injury mechanism and severity (OTA classification and Gustilo-Anderson type open injury) were comparable between the 2 treatment groups. There was no significant difference (P = 1.0) in nonunions between the titanium group (3/25) and the stainless steal group (9/79). However, higher implant failure rates (41% vs 20%, P = 0.09) and reoperation rates (9% vs 0%, P = 0.19) for the titanium- versus stainless steel–treated groups approach statistical significance. In multivariable analysis, smoking and open fracture were the strongest independent risk factors for nonunion.
Conclusions: These results do not show a difference in union rates of distal femoral fractures attributable to metallurgy of the lateral locked plate. Furthermore, there may be a higher incidence of implant failure and reoperation rates for the titanium LISS, which favors the use of a stainless steel implant. Further prospective trials will be required to substantiate these finding and study the relative importance of other technical factors such as plate length and screw configuration.Disclosure: (n=Respondent answered 'No' to all items indicating no conflicts; 1=Board member/owner/officer/committee appointments; 2=Medical/Orthopaedic Publications; 3=Royalties; 4=Speakers bureau/paid presentations; 5A=Paid consultant or employee; 5B=Unpaid consultant; 6=Research or institutional support from a publisher; 7=Research or institutional support from a company or supplier; 8=Stock or Stock Options; 9=Other financial/material support from a publisher; 10=Other financial/material support from a company or supplier).
• 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