Blade plate compared with locking plate for tibiotalocalcaneal arthrodesis: a cadaver study.

BACKGROUND

We hypothesized that a locking plate would be stronger than a blade plate for tibiotalocalcaneal arthrodesis under dorsiflexion and torsional loading.

MATERIALS AND METHODS

Nine pairs of matched cadaveric lower extremities were used. BMD was obtained for each specimen. Each received a retrograde augmentation screw and a stainless steel LC-angled blade plate (Synthes, Paoli, PA) or a stainless steel LCP proximal humerus locking plate (Synthes, Paoli, PA). Specimens were cyclically loaded in dorsiflexion to simulate 6 weeks of partial weightbearing and then monotonically loaded to failure. Specimens were removed from the load frame and remounted to simulate fusion. The specimen received an axial load of 720 N and was externally rotated proximal to the construct at 5 degrees/sec to fracture. Data were compared with a Student's t-test. Pearson correlation analysis was used to determine whether bone mineral density was significantly related to measured parameters. Significance was set at p < or = 0.05.

RESULTS

The locking plate group had higher initial stiffness, higher dorsiflexion and torsional load to failure, and lower construct deformation than the blade plate group. Bone mineral density was positively correlated with dorsiflexion failure load and torsional failure load in the locking plate construct.

CONCLUSION

Fixation with the locking plate was superior to that with the blade plate.

CLINICAL RELEVANCE

Use of a locking plate may be an effective fixation technique in tibiotalocalcaneal arthrodesis, especially in complex hindfoot reconstructions with bone loss or deformity.