He Song,* Aobo Wang,* Lei Zang, Tianyi Wang, Shuo Yuan, Ning Fan, Peng Du

Department of Orthopedics, Beijing Chaoyang Hospital, Capital Medical University, Beijing, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Lei Zang, Department of Orthopedics, Beijing Chaoyang Hospital, Capital Medical University, 5 JingYuan Road, Shijingshan District, Beijing, 100043, People’s Republic of China, Tel +86-010-51718268, Email zanglei@ccmu.edu.cn

Purpose: Adjacent disc degeneration (ADD) is a common postoperative complication after percutaneous kyphoplasty (PKP). However, risk factors for ADD after PKP have not been reported. This study aimed to determine whether osteoporotic vertebral compression fracture (OVCF) following PKP is associated with a high risk for ADD and to identify the risk factors for ADD.
Patients and methods: Consecutive patients who underwent PKP at our center between January 2015 and January 2021 were retrospectively reviewed. The incidence of ADD was calculated and specific subgroups of ADD were identified. Demographic, clinical baseline, and radiologic data were analyzed using univariate and multivariate analyses to identify the risk factors associated with ADD.
Results: 130 eligible patients were included, and the incidence rate of ADD distinct from primary degeneration was 42.3%. Patients with OVCFs who underwent PKP had a high risk of developing ADD. The independent risk factors included the presence of intradiscal cement leakage (ICL; odds ratio [OR] 6.292; 95% confidence interval [CI] 2.588– 15.299; P < 0.001) and pre-operative cranial disc of the injured vertebrae degeneration (Pfirrmann grade ≥IV; OR 3.575; 95% CI 1.515– 8.438; P = 0.004).
Conclusion: Patients with OVCFs who underwent PKP were more likely to develop ADD, and most of the degenerated discs occurred in the vertebrae above the level of injury. ICL and pre-operative cranial disc of the injured vertebrae degeneration (Pfirrmann grade ≥IV) were independent risk factors for developing ADD in these patients.

Keywords: adjacent disc degeneration, percutaneous kyphoplasty, osteoporotic vertebral compression fracture, risk factors