STUDY DESIGN: A retrospective study of radiographic parameters of patients who underwent lumbar spinal pedicle screw insertion.PURPOSE: The optimal length of pedicle screws is often determined by the lateral radiograph during minimally invasive surgery (MIS). Compared with open techniques, measuring the precise length of screws or assessing the cortical breach is challenging. This study aims to ascertain the optimal pedicle screw lengths on intraoperative lateral radiographs for L1–L5.OVERVIEW OF LITERATURE: Research has revealed that optimal pedicle screw length is essential to optimize fixation, especially in osteoporotic patients; however, it must be balanced against unintentional breach of the anterior cortex, risking injury to adjacent neurovascular structures as demonstrated by case reports.METHODS: We reviewed intra- and postoperative computed tomography scans of 225 patients who underwent lumbar pedicle screw insertion to ascertain which of the inserted screws were ‘optimal screws.’ The corresponding lengths of these screws were analyzed on postoperative lateral radiographs to ascertain the ideal position that a screw should attain (expressed as a percentage of the entire vertebral body length).RESULTS: We reviewed 880 screws of which 771 were optimal screws. We noted a decreasing trend in average optimal percentages of insertion into the vertebral body for pedicle screws going from L1 (average=87.60%) to L5 (average=78.87%). The subgroup analysis revealed that there was an increasing percentage of screws directed in a straight trajectory from L1 to L5, compared to a medially directed trajectory.CONCLUSIONS: During MIS pedicle screw fixation, this study recommends that pedicle screws should not exceed 85% of the vertebral body length on the lateral view for L1, 80% for L2–L4, and 75% for L5; this will minimize the risk of anterior cortical breach yet maximize pedicle screw purchase for fixation stability.
Humans ; Lumbar Vertebrae ; Minimally Invasive Surgical Procedures ; Pedicle Screws ; Radiography ; Retrospective Studies

Retrospective review.

Retrospective review.

STUDY DESIGN: Retrospective database analysis. PURPOSE: To identify risk factors that predict mortality following acute spine fractures in geriatric patients of Singapore. OVERVIEW OF LITERATURE: Acute geriatric spinal fractures contribute significantly to local healthcare costs and hospital admissions. However, geriatric mortality following acute spine fractures is scarcely assessed in the Asian population. METHODS: Electronic records of 3,010 patients who presented to our hospital’s emergency department and who were subsequently admitted during 2004–2015 with alleged history of traumatic spine fractures were retrospectively reviewed, and 613 patients (mean age, 85.7±4.5 years; range, 80–101 years; men, 108; women, 505) were shortlisted. Mortality rates were reviewed up to 1 year after admission and multivariate analyses were performed to identify independent risk factors correlating with mortality. RESULTS: Women were more susceptible to spine fractures (82.4%), with falls (77.8%) being the most common mechanism of injury. Mortality rates were 6.0%, 8.2%, and 10.4% at 3, 6, and 12 months, respectively. The most common causes of death at all 3 time points were pneumonia and ischemic heart disease. Based on the multivariate analysis at 1-year follow-up, elderly women had a lower mortality rate compared to men (p<0.001); mortality rates increased by 6.3% (p=0.024) for every 1-year increase in the patient’s age; and patients with an American Spinal Injury Association (ASIA) score of A–C had a much higher mortality rate compared to those with an ASIA score of D–E (p<0.001). CONCLUSIONS: An older age at presentation, male sex, and an ASIA score of A–C were identified as independent factors predicting increased mortality among geriatric patients who sustained acute spine fractures. The study findings highlight at-risk groups for acute spine fractures, thereby providing an opportunity to develop strategies to increase the life expectancy of these patients.
Accidental Falls ; Aged ; Asia ; Asian Continental Ancestry Group ; Cause of Death ; Emergency Service, Hospital ; Female ; Follow-Up Studies ; Health Care Costs ; Humans ; Life Expectancy ; Male ; Mortality ; Multivariate Analysis ; Myocardial Ischemia ; Pneumonia ; Retrospective Studies ; Risk Factors ; Singapore ; Spinal Cord Injuries ; Spinal Fractures ; Spinal Injuries ; Spine