To explore the management strategy and indications for revisionary internal fixation after percutaneous kyphoplasty/percutaneous vertebroplasty (PKP/PVP) in cancellous vertebral fractures.

A retrospective analysis was made of the 676 cases of single-segment PKP/PVP at Department of Orthopaedics, The Affiliated Hospital to Qingdao University from January 2008 to January 2019. They were subjected to 4 different managements after their primary PKP/PVP: rehabilitation without any treatment in 637 cases, conservative treatment in 19 cases (including 3 ones who refused any revision), KP/VP revision in 12 cases and internal fixation revision in 8 cases. The rate of volume reduction after bone cement dispersion (Vx) was calculated using software Mimics 17.0 on the basis of primary CT data of all the patients. The correlation regression analysis was made between the revision rate and the approximate quantization value of Vx. The Glasgow Coma Score (GCS) of conscious state was used to evaluate the 39 patients after failure of their primary surgery before the surgical strategy for revision was worked out. The cobb angle, pelvic incidence angle (PI), pelvic inclination angle (PT), sacral inclination angle (SS), sagittal deviation (SVA), pain visual analogue scale (VAS) were measured and recorded before operation and at the last follow-up for the KP/VP revision group and internal fixation revision group, indicated as Δcobb, ΔPI, ΔPT, ΔSS, ΔSVA and ΔVAS, respectively. The indexes were compared between the 2 groups.

The incidence of osteoporotic vertebral fractures treated with internal fixation revision was 1.18% (8/676). The correlation between Vx and revision rate was y=0.53+0.04x (P<0.05). The regression analysis showed that Vx was positively correlated with the revision rate (r²=0.860, P=0.001) and the fitting curve was correlated (r²=0.916, P=0.001). The GSC scores revealed 31 normal, 6 mild disturbance and 2 moderate disturbance cases. There were no significant differences in gender, age or VAS scores between the KP/VP revision group and the internal fixation revision group (P>0.05). There was a significant difference in Δcobb between the 2 revision groups (6.3°±7.5° versus 19.2°±14.8°) (P<0.05), but there were no significant differences between the 2 groups in ΔPI (4.1°±5.2° versus 3.3°±6.7°), ΔPT (0.7°±4.6° versus 0.4°±3.2°), ΔSS (3.7°±6.2° versus 3.1°±5.3°) or ΔSVA (-3.2±11.9 mm versus -7.9±9.5 mm) (P>0.05).

The outcomes of primary PKP/PVP have a great impact on the decision-making of internal fixation revision. The mode and extent of diffusion after initial vertebral cement perfusion are particularly related to the revision rate. The revision plan should depend on clinical symptoms. The internal fixation revision should be individualized to ensure the quality of life of the patients in line with the principles of "resolving symptoms" and "moderate correction" .

Osteoporosis; Vertebroplasty; Fracture fixation, internal; Revision; Indication