Predictors of poor outcome following lumbar spinal fusion surgery: a prospective observational study to derive two clinical prediction rules using British Spine Registry data.

PURPOSE: Lumbar spinal fusion surgery (LSFS) is common for lumbar degenerative disorders. The objective was to develop clinical prediction rules to identify which patients are likely to have a favourable outcome to inform decisions regarding surgery and rehabilitation. METHODS: A prospective observational study recruited 600 (derivation) and 600 (internal validation) consecutive adult patients undergoing LSFS for degenerative lumbar disorder through the British Spine Registry. Definition of good outcome (6 weeks, 12 months) was reduction in pain intensity (Numerical Rating Scale, 0-10) and disability (Oswestry Disability Index, ODI 0-50) > 1.7 and 14.3, respectively. Linear and logistic regression models were fitted and regression coefficients, Odds ratios and 95% CIs reported. RESULTS: Lower BMI, higher ODI and higher leg pain pre-operatively were predictive of good disability outcome, higher back pain was predictive of good back pain outcome, and no previous surgery and higher leg pain were predictive of good leg pain outcome; all at 6 weeks. Working and higher leg pain were predictive of good ODI and leg pain outcomes, higher back pain was predictive of good back pain outcome, and higher leg pain was predictive of good leg pain outcome at 12 months. Model performance demonstrated reasonable to good calibration and adequate/very good discrimination. CONCLUSIONS: BMI, ODI, leg and back pain and previous surgery are important considerations pre-operatively to inform decisions for surgery. Pre-operative leg and back pain and work status are important considerations to inform decisions for management following surgery. Findings may inform clinical decision making regarding LSFS and associated rehabilitation.

Development and validation of two clinical prediction models to inform clinical decision-making for lumbar spinal fusion surgery for degenerative disorders and rehabilitation following surgery: protocol for a prospective observational study.

INTRODUCTION: Potential predictors of poor outcome will be measured at baseline: (1) preoperatively to develop a clinical prediction model to predict which patients are likely to have favourable outcome following lumbar spinal fusion surgery (LSFS) and (2) postoperatively to predict which patients are likely to have favourable long-term outcomes (to inform rehabilitation). METHODS AND ANALYSIS: Prospective observational study with a defined episode inception of the point of surgery. Electronic data will be collected through the British Spine Registry and will include patient-reported outcome measures (eg, Fear-Avoidance Beliefs Questionnaire) and data items (eg, smoking status). Consecutive patients (≥18 years) undergoing LSFS for back and/or leg pain of degenerative cause will be recruited. EXCLUSION CRITERIA: LSFS for spinal fracture, inflammatory disease, malignancy, infection, deformity and revision surgery. 1000 participants will be recruited (n=600 prediction model development, n=400 internal validation derived model; planning 10 events per candidate prognostic factor). The outcome being predicted is an individual's absolute risk of poor outcome (disability and pain) at 6 weeks (objective 1) and 12 months postsurgery (objective 2). Disability and pain will be measured using the Oswestry Disability Index (ODI), and severity of pain in the previous week with a Numerical Rating Scale (NRS 0-10), respectively. Good outcome is defined as a change of 1.7 on the NRS for pain, and a change of 14.3 on the ODI. Both linear and logistic (to dichotomise outcome into low and high risk) multivariable regression models will be fitted and mean differences or ORs for each candidate predictive factor reported. Internal validation of the derived model will use a further set of British Spine Registry data. External validation will be geographical using two spinal registries in The Netherlands and Switzerland. ETHICS AND DISSEMINATION: Ethical approval (University of Birmingham ERN_17-0446A). Dissemination through peer-reviewed journals and conferences.

Posterior fracture dislocation of the hip joint: the value of the obturator-oblique view with the hip still dislocated.

OBJECTIVES: To determine the value of the Judet oblique views taken while the hip is still dislocated. STUDY DESIGN: Radiological review. SETTING: Level I trauma center. METHOD: In addition to the traditional views in fifty of 110 fracture-dislocations, Judet views were carried out with the hip still dislocated. Each of the respective views was viewed with the reviewer blinded to diagnosis and the fracture classified according to the information available on that view. The percent accuracy of each view was then calculated by comparing radiologic with intraoperative classification. Under the pretext that if any view enabled a more accurate classification of the fracture, it must be providing more information, we assessed the quantitative value of each radiologic view according to our ability to accurately classify the fracture. RESULTS: Using the CT scan alone, classification was accurate in 82 percent of cases because the CT often overdemonstrated the degree of comminution. When the added information available from the traditional radiographs was included, there was only a slight improvement (82 percent versus 84 percent). This was increased to 96 percent when the obturator-oblique dislocated view was included. CONCLUSION: Because it provides an uninterrupted view of the posterior wall, demonstrates the displacements of fragments, and provides a comparison for the reduced view, which greatly augments the available information, the obturator-oblique dislocated view should be done routinely in the assessment of all posterior fracture dislocations of the hip joint.