A novel bone cement screw system combined with vertebroplasty for the treatment of Kummell disease with bone deficiency at the vertebral anterior border: A minimum 3-year follow-up study

Abstract Background: When vertebroplasty is used to treat Kummell disease with bone deficiency at vertebral anterior border, bone cement displacement often occurs intraoperative or postoperative. We designed and used a new bone cement screw system to avoid the serious complication. The purpose of this study is to evaluate the safety and effectiveness of this novel operation method through more than 3 years of follow-up. Methods: From January 2012 to August 2016, 27 patients suffering from single-segment Kummell disease with bone deficiency at vertebral anterior border were treated by vertebroplasty combined with novel bone cement screw. Bone cement is released into the diseased vertebrae through screw to fully fill the intravertebral vacuum cleft. Screw fixation of bone cement can avoid intraoperative or postoperative displacement. All patients were operated by unilateral technique, only one screw was implanted for each patient. The clinical efficacy was evaluated using Odom’s criteria and statistical analysis based on the results of vertebral body index (VBI), vertebral body angle (VBA), bisegmental Cobb angle (BCA), visual analogue scale (VAS), oswestry disability index (ODI), and the MOS 36-item short from health survey (SF-36). Results: The operation was completed successfully in 27 cases. The average operation time was 49.63±10.82 min, and the average volume of cement injected was 4.70±0.87 ml. The patients’ preoperative VBI, VBA, BCA, VAS and ODI scores were 43.11±5.94, 21.04±2.55, 45.00±6.26, 7.59±0.84, and 79.85±7.58, respectively. The postoperative measurements were 78.70±2.55, 12.70±2.11, 26.11±4.73, 3.22±0.93 and 50.04±9.28. At the last follow-up, the measurements were 78.04±2.30, 13.15±2.38, 27.07±4.87, 2.04±0.65, and 22.85±5.06, respectively. There was significant difference between the preoperative and postoperative data, as well as the preoperative and the last follow-up data (P<0.05). Compared the results of SF-36 preoperative and at the last follow-up, there were significant differences in physical function, role-physical, body pain, vitality, and social function these 5 items (P<0.05). However, there were no significant differences in general health, emotional function and mental health. Finally, 26 patients (96.3%) had good to excellent clinical outcomes according to Odom's criteria. Conclusions: This 3-year follow-up study shows that the novel bone cement screw system combined with vertebroplasty has a good short and medium-term therapeutic effect on patients with Kummell disease and bone deficiency at vertebral anterior border, while its long-term efficacy is subject to further studies.