The analysis of the impact of bone cement leakage through the endplate on the prognosis of patients after PKP on intervertebral disc

Abstract

Background:There is a high incidence in the elderly who come down with osteoporotic vertebral compression fracture (OVCF) and percutaneous kyphoplasty (PKP) is an effective solution which can relieve pain quickly. Previous studies have shown that both the volume and the distribution of bone cement filling are related to the clinical outcome after PKP surgery. However, the influence of bone cement leakage through the endplate after PKP on intervertebral disc remains to be explained. Methods:118 patients with single level OVCF operated by PKP were retrospectively reviewed from 2015 to 2020. These patients were grouped according to the degree of bone cement leakage. Group A: Bone cement leakage involving one endplate relative to the intervertebral disc. Group B: Bone cement leakage involving one endplate and the adjacent disc. Group C: Bone cement leakage involving both endplates of the intervertebral disc. The following variables were reviewed: gender, age, BMI, BMD and surgical parameters including cement volume (CV), Oswestry Disability Index (ODI), Visual analogue Scale (VAS), Anterior vertebral height ration (AVHR), Local kyphotic angle (LKA), Intervertebral space height (ISH) and the incidence of complications.Results:Compared with the preoperative for all groups, the VAS, ODI, AVHR, LKA and ISH were improved significantly after PKP. There is no significant difference among groups in AVHR and LKA (P> 0.05). Compared with preoperative levels, there was a significant reduction in fracture perivertebral pain in all groups after the surgery, but at the last follow-up, the VAS of Group C were worser than other groups (3.28±0.29 vs. 2.55±0.67vs. 1.73±0.51, P <0.05) and the ODI of Group C were also worser than other groups (44.46±6.65 vs. 35.77±6.33 vs. 29.80±5.96, P <0.05). At the last follow-up, the ISH of group C was worser than group B and group C (4.04±0.38 vs. 4.63±0.27 vs. 5.19±0.34, P <0.05). The complications including the adjacent vertebral fracture (AVF) and backache of group A was (1/39, 2.5%), that of group B was (6/33, 15.4%) and that of group C was (17/22, 42.5%). The incidence of complications in the group C was significantly higher than that in the other groups (P＜0.05). Conclusions:As the area of bone cement leaking from one endplate to another endplate of the intervertebral disc increases, there is no significant difference in the short-term effect after surgery, but the patient's long-term postoperative efficacy becomes worse. The incidence of AVF and back pain of adjacent vertebral bodies increases. It even aggravated the degeneration of the intervertebral disc and the symptoms of discogenic neuralgia appeared.