Outcomes of the use of cement-augmented cannulated pedicle screws in lumbar spinal fusion.

BACKGROUND CONTEXT: There are few studies of the radio-clinical outcomes of cement-augmented cannulated pedicle screw (CPS) fixation in osteoporotic patients. PURPOSE: To compare the radiological and clinical outcomes between groups receiving cement-augmented CPS and solid pedicle screws (SPS) in lumbar fusion surgery. STUDY DESIGN/SETTING: Retrospective comparative study PATIENT SAMPLE: A total of 187 patients who underwent lumbar fusion surgery for degenerative spinal stenosis or spondylolisthesis from 2014 to 2019. OUTCOME MEASURES: Radiological evaluation included screw failure, cage failure, rod breakage, and fusion grade at postoperative 6 months and 1 year. Pre- and postoperative visual analog scales for back pain (VAS-BP), leg pain (VAS-LP), Korean Oswestry disability index (K-ODI), and postoperative complications were also compared. METHODS: Outcomes of patients with high risk factors for implant failure [old age, osteoporosis, autoimmune disease or chronic kidney disease (CKD)] who underwent open transforaminal lumbar interbody fusion with cement-augmented CPS fixation (Group C, n=55) or SPS fixation (Group S, n=132) were compared. RESULTS: 324 pedicle screws in Group C and 775 pedicle screws in Group S were analyzed. Group C had a significantly higher average age and lower T-score, and included more patients with autoimmune disease and CKD than group S (all p<.05). Clear zones, screw migration and loss of correction were significantly less frequent in Group C (all p<.05). Thirteen screw breakages were observed; they were only in Group C (4.0%) and all were in the proximal of the two holes. Interbody and posterolateral fusion rates were not significantly different. At last follow-up, all clinical parameters including VAS-BP, VAS-LP, and K-ODI scores had improved significantly in both groups. Postoperative complications were not significantly different in the two groups. CONCLUSION: In lumbar fusion surgery, using cement-augmented CPS in high-risk groups for implant failure could be a useful technical option for reducing acute radiological complications and obtaining clinical results comparable to those obtained using SPS in patients with low risk of implant failure. LEVEL OF EVIDENCE: Level 4.

Incidence of acute spinal cord injury and associated complications of methylprednisolone therapy: a national population-based study in South Korea.

STUDY DESIGN: Retrospective population-based cohort study OBJECTIVES: To evaluate the incidence of acute spinal cord injury (SCI) in South Korea, and the prescription rates and complications related to high dose methylprednisolone therapy. SETTING: Health Insurance Review and Assessment Service (HIRA) data METHODS: National database of the Korean HIRA between 2007 and 2017 was reviewed. To identify patients with acute SCI and the use of high dose methylprednisolone, International Classification of Disease revision codes, medical behavior codes and examination codes were used. Patients were grouped according to whether or not they received methylprednisolone therapy (MP group vs non-MP group). RESULTS: The average age-adjusted incidence of acute SCI per 1,000,000 persons was 26.4 and the peak incidence was in the 50s overall. The methylprednisolone prescription rate was highest in 2012 (76%) and continued to decrease thereafter, being lowest in 2017 (41%). The MP group showed higher complication rates in terms of pneumonia (OR 1.8, 95% CI, 1.62-2.0), GI bleeding (OR 1.2, 95% CI, 1.05-1.38), and UTI (OR 1.68, 95% CI, 1.53-1.84). The average length of hospitalization was longer in patients who received methylprednisolone (26.5 days vs. 24.4 days, p < 0.05). CONCLUSIONS: The average age-adjusted incidence of acute SCI for 11 years was 26.4 per 1,000,000 persons and highest in 50s. Strategies should be established, and national health resources should be allocated to prevent acute SCI from occurring in older people. The prescription rate of high dose methylprednisolone for acute SCI is decreasing in South Korea but it is still high.