The Effect of Transpedicular Injection of Recombinant Human Bone Morphogenetic Protein-2/Beta-Tricalcium Phosphate Carrier on the Prevention of Proximal Junctional Kyphosis in Adult Spinal Deformity Surgery: A Pilot Study

Neurosurgery 96:986–996, 2025

The study explores the use of recombinant human bone morphogenetic protein-2 (rhBMP-2) with beta-tricalcium phosphate (β-TCP) to prevent proximal junctional kyphosis (PJK) in adult spinal deformity surgery. Results indicate reduced PJK incidence and increased bone density at the upper instrumented vertebra.

• The study explores the use of transpedicular injection of recombinant human bone morphogenetic protein-2 (rhBMP-2) with a beta-tricalcium phosphate (β-TCP) carrier to prevent proximal junctional kyphosis (PJK) in adult spinal deformity (ASD) surgery.

• 25 patients received rhBMP-2 injections, and their outcomes were compared with two control groups with 66 and 63 patients each.

• Results showed a significantly lower incidence of PJK in the rhBMP-2 group compared to control groups.

• The injection also led to a significant increase in trabecular bone density at the upper instrumented vertebra (UIV).

• Multivariate analysis indicated that rhBMP-2 injection at the UIV had a protective effect against PJK.

• The study suggests that this method can be easily integrated into surgical procedures to enhance bone density and reduce PJK risk.

• Limitations include the small sample size and lack of randomization, warranting further studies.

• The study concludes that rhBMP-2/β-TCP injection is a promising strategy for preventing PJK in ASD surgery.