Outcomes of the First Generation Locking Plate and Minimally Invasive Techniques Used for Fractures About the Knee

Background: Locking plate technology was developed approximately 25-years-ago and has been successfully used since. Newer designs and material properties have been used to modify the original design, but these changes have yet to be correlated to improved patient outcomes. The purpose of this study was to evaluate the outcomes of first-generation locking plate (FGLP) and screw systems at our institution over an 18 year period.

Methods: Between 2001 to 2018, 76 patients with 82 proximal tibia and distal femur fractures (both acute fracture and nonunions) who were treated with a first-generation titanium, uniaxial locking plate with unicortical screws (FGLP), also known as a LISS plate (Synthes Paoli Pa), were identified and compared to 198 patients with 203 similar fracture patterns treated with 2nd and 3rd generation locking plates, or Later Generation Locking Plates (LGLP). Inclusion criteria was a minimum of 1-year follow-up. At latest follow-up, outcomes were assessed using radiographic analysis, Short Musculoskeletal Functional Assessment (SMFA), VAS pain scores, and knee ROM. All descriptive statistics were calculated using IBM SPSS (Armonk, NY).

Results: A total of 76 patients with 82 fractures had a mean 4-year follow-up available for analysis. There were 76 patients with 82 fractures fixed with a First-generation locking plate. The mean age at time of injury for all patients was 59.2 and 61.0% were female. Mean time to union for fractures about the knee fixed with FGLP was by 5.3 months for acute fractures and 6.1 months for nonunions. At final follow-up, the mean standardized SMFA for all patients was 19.9, mean knee range of motion was 1.6°-111.9°, and mean VAS pain score was 2.7. When compared to a group of similar patients with similar fractures and nonunions treated with LGLPs there were no differences in outcomes assessed.

Conclusion: Longer-term outcomes of first-generation locking plates (FGLP) demonstrate that this construct provides for a high rate of union and low incidence of complications, as well as good clinical and functional results. Level of Evidence: III.