[Proximal tibia fracture treatment with a new locking device with polyaxial screw placement: technique and early results]

Abstract

Background: Surgical treatment of tibial head fractures can be challenging due to the close anatomic relationship to the knee joint which can be affected including its intraarticular structures. Frequently, soft tissue damages are present which can have a strong impact on the planning and choice of surgical technique. An important therapeutic requirement is the anatomic reconstruction and high primary stability to allow early functional treatment. The aim of the present study was to describe a recent locking device and its surgical technique and to analyse the early results.

Material and methods: The Non-Contact-Bridging Plate for the proximal tibia (NCB® PT, Zimmer Inc.) features a polyaxial locking mechanism which allows both compression and locking with the same screw. The system can be applied both minimally invasively and open. 36 patients (16 female, 20 male; average age 53 years) with three type A, 21 type B and 12 type C fractures according to the AO classification were treated. In 22 cases the system was applied open and in 14 minimally invasively. Clinical and radiological follow-up was obtained at 6 weeks, 3, 6 and 12 months.

Results: The handling of the system turned out to be straightforward after an initial learning curve. Implant failure was not detected in our sample. The minimally invasive technique can be beneficial in cases of severe soft tissue damage, but must not compromise the quality of reduction. The functional result at 1-year follow-up using a knee score was good or very good and comparable to the literature. The rate of general surgical complications was 11 % (haematoma, superficial or deep wound infection). Implant-related complications were not detected. At the 3-months' follow-up 44 % and at the 12-months' 100 % of the fractures were healed on X-ray.

Conclusion: The NCB PT plate offers a broad variety of treatment options due to the specific locking mechanism and the fact that it can be applied both minimally invasively and open. In cases of intraarticular involvement the application of compression and locking with the same screw turned out to be very beneficial. The primary stability of the system allows early functional treatment. Clinical results and complication rates of the present study are comparable to those in the literature.