Split-Depressed Lateral Tibial Plateau Fractures: A Comparison of Augmented Percutaneous Screws Versus Augmented Plate and Screw Construct in a Cadaveric Model.

OBJECTIVES

To compare the strength of fixation of percutaneous screw versus plate/screw fixation in a paired cadaver model of OTA 41-B3 (Schatzker type II) split-depression fractures of the lateral tibial plateau.

METHODS

Six matched pairs of cadaveric knees were acquired. An OTA 41-B3 (Schatzker type II) split-depression fracture was created in all specimens using a standardized method. One specimen from each matched pair of knees was fixed with percutaneous screws, and the other was fixed with a plate/screw construct. All specimens underwent augmentation of the central metaphyseal defect with calcium phosphate. Mean residual displacement (depression) was measured on thin-slice high-resolution computed tomography using a standardized methodology following 3 experimental conditions: (1) after they were fixed, before loading; (2) unloaded cycling (simulating postoperative range of motion exercises); and (3) loaded cycling (simulating postoperative weight-bearing). Load to failure was also compared.

RESULTS

After adjustment for baseline measurements, there was no significant difference in mean residual depression of the lateral tibial plateau between treatments groups after unloaded or loaded cyclic testing. Mean residual depression was less than 1 mm in both the treatment groups. Load to failure was statistically equivalent between treatment groups.

CONCLUSIONS

In our cadaveric study, in combination with calcium phosphate augmentation for both methods, percutaneous screw fixation conferred comparable strength of fixation compared with plate/screw constructs for treatment of OTA 41-B3 (Schatzker type II) tibial plateau fractures.