Bisegmental Posterior Stabilisation Of Thoracolumbar Fractures With Polyaxial Pedicle Screws: Does Additional Balloon Kyphoplasty Retain Vertebral Height?

We retrospectively evaluated single-level compression fractures (T12-L3) scheduled for a short-segment POS (posterior-only stabilization) using polyaxial screws. Patients averaged 55.7 years (range, 19-65). Patients received either POS or, concomitantly, BK (balloon kyphoplasty) of the fractured vertebrae as well. Primary endpoint was the radiological outcome at the last radiographic follow-up prior to implant removal. POS together with BK of the fractured vertebrae resulted in a significant improvement of the local kyphosis angle and vertebral body compression rates immediately post-OP. During the further course of FU, a considerable loss of correction was observed post-OP in both groups. (Local KA: pre-OP/post-OP/FU: 12.6 +/- 4.8/3.35 +/- 4.8/11.6 +/- 6.0; anterior vertebral body compression%: pre-OP/post-OP/FU: 71.94 +/- 12.3/94.78 +/- 19.95/78.17 +/- 14.74). VAS was significantly improved from 7.2 +/- 1.3 pre-OP to 2.7 +/- 1.3 (P<0.001) at FU. We found a significant restoration of the vertebral body height by BK. Nevertheless, follow-up revealed a noticeable loss of reduction. Given the fact that BK used together with polyaxial screws did not maintain intra-operative reduction, our data do not support this additional maneuver when used together with bi-segmental polyaxial pedicle screw fixation.