Session III - Femur

Soft Tissue Complications in the Treatment of Complex Fractures of the Proximal Tibia with Use of the Less Invasive Stabilization System

Frederic B. Wilson, MD¹; Mary C. Sargent, MD¹; Kyle F. Dickson, MD¹; Matthew Williams, MD²; Meredith Warner, MD¹; Barry L. Riemer, MD²; Joseph Byrne, MD¹;

¹Tulane University School of Medicine, New Orleans, Louisiana, USA;

²Louisiana State University School of Medicine, Baton Rouge, Louisiana, USA

Purpose: The Less Invasive Stabilization System (LISS) is a set of anatomically pre-bent locking plates designed to function as an internal external fixator for fixation of distal femoral and proximal tibial fractures. In the proximal tibia, high union rates have been reported with use of this technique with unicortical, fixed-angle screws, and submuscular plate placement to stabilize the fracture site without stripping the soft tissue and vascular attachments. Reported soft tissue complication and infection rates have been as low as 1 to 3.8%. However, the early experience at our center suggests a higher number of such complications and prompted a review of infection and soft tissue complications encountered with use of the LISS plate to discern contributing factors.

Methods: A retrospective records search was performed of all patients treated at a level I trauma center between January 1, 1999 and June 30, 2002 who had diagnostic codes 823.00 through 823.90. We identified 49 patients with proximal tibia or tibial plateau fractures treated with the LISS system. Their charts were further reviewed to identify fracture type, injury mechanism, patient comorbidities, treatment outcomes, and soft tissue or infection complications. Radiographs were reviewed to assess alignment and plate placement. The "fit" of the plate in terms of its profile on AP and oblique views and its AP ratio in terms of plate width at the proximal end divided by the AP dimension of the patient's tibia was also measured. These parameters were then compared with the incidence of complications to determine what correlations existed.

Results: The preponderance of the fractures in the 49 patients resulted from motor vehicle accidents. Although nonunions were rare, infection and soft tissue complication occurred in 7 patients (14%). Three of the patients required removal of hardware and free flap to gain coverage. In addition to patient comorbidities, prominence of the plate or proximal, anterior plate placement or both as well as size of the plate in comparison with the anatomy of the proximal tibia appeared to correlate with infection and soft tissue complication rates.

Discussion and Conclusion: Complex proximal tibia fractures are difficult to treat with high complication rates reported. It was hoped that use of the LISS plate system would herald an era of reduced complication rates. However, review of our early experience reveals acceptable union rates and alignment but higher than expected infection and soft tissue complication rates. Plate placement in conjunction with patient comorbidities appear to influence outcome; those patients who had infection and soft tissue breakdown had more anterior, proximal and, therefore, more prominent hardware.

Significance: Many surgeons have rushed to embrace the new fixed-plate technology. Although the LISS plate offers many advantages in terms of stability, our preliminary results should serve as a note of caution in their use and as a stimulus for more study in terms of the indications, surgical technique, and design of this system.