Aims

Spinopelvic characteristics influence the hip’s biomechanical behaviour. However, to date there is little knowledge defining what ‘normal’ spinopelvic characteristics are. This study aims to determine how static spinopelvic characteristics change with age and ethnicity among asymptomatic, healthy individuals.

In multilevel posterior cervical instrumented fusions, extending the fusion across the cervico-thoracic junction at T1 or T2 (CTJ) has been associated with decreased rate of re-operation and pseudarthrosis but with longer surgical time and increased blood loss. The impact on patient reported outcomes (PROs) remains unclear. The primary objective was to determine whether extending the fusion through the CTJ influenced PROs at 3 and 12 months after surgery. Secondary objectives were to compare the number of patients reaching the minimally clinically important difference (MCID) for the PROs and mJOA, operative time duration, intra-operative blood loss (IOBL), length of stay (LOS), discharge disposition, adverse events (AEs), re-operation within 12 months of the surgery, and patient satisfaction.

This is a retrospective analysis of prospectively collected data from a multicenter observational cohort study of patients with degenerative cervical myelopathy. Patients who underwent a posterior instrumented fusion of 4 levels of greater (between C2-T2) between January 2015 and October 2020 with 12 months follow-up were included. PROS (NDI, EQ5D, SF-12 PCS and MCS, NRS arm and neck pain) and mJOA were compared using ANCOVA, adjusted for baseline differences. Patient demographics, comorbidities and surgical details were abstracted. Percentafe of patient reaching MCID for these outcomes was compared using chi-square test. Operative duration, IOBL, AEs, re-operation, discharge disposittion, LOS and satisfaction were compared using chi-square test for categorical variables and independent samples t-tests for continuous variables.

A total of 206 patients were included in this study (105 patients not crossing the CTJ and 101 crossing the CTJ). Patients who underwent a construct extending through the CTJ were more likely to be female and had worse baseline EQ5D and NDI scores (p> 0.05). When adjusted for baseline difference, there was no statistically significant difference between the two groups for the PROs and mJOA at 3 and 12 months. Surgical duration was longer (p 0.05). Satisfaction with the surgery was high in both groups but significantly different at 12 months (80% versus 72%, p= 0.042 for the group not crossing the CTJ and the group crossing the CTJ, respectively). The percentage of patients reaching MCID for the NDI score was 55% in the non-crossing group versus 69% in the group extending through the CTJ (p= 0.06).

Up to 12 months after the surgery, there was no statistically significant differences in PROs between posterior construct extended to or not extended to the upper thoracic spine. The adverse event profile did not differ significantly, but longer surgical time and blood loss were associated with construct extending across the CTJ.

Symptomatic lumbar spinal stenosis is a common entity and increasing in prevalence. Limited evidence is available regarding patient reported outcomes comparing primary vs revision surgery for those undergoing lumbar decompression, with or without fusion. Evidence available suggest a lower rate of improvement in the revision group. The aim of this study was to assess patient reported outcomes in patients undergoing revision decompression, with or without fusion, when compared to primary surgery.

Patient data was collected from the Canadian Spine Outcomes Research Network (CSORN) database. Patients undergoing lumbar decompression without or without fusion were included. Patients under 18, undergoing discectomy, greater than two level decompressions, concomitant cervical or thoracic spine surgery were excluded. Demographic data, smoking status, narcotic use, number of comorbidities as well as individual comorbidities were included in our propensity scores. Patients undergoing primary vs revision decompression were matched in a four:one ratio according to their scores, whilst a separate matched cohort was created for those undergoing primary vs revision decompression and fusion. Continuous data was compared using a two-tailed t-test, whilst categorical variables were assessed using chi-square test.

A total of 555 patients were included, with 444 primary patients matched to 111 revision surgery patients, of which 373 (67%) did not have fusion. Patients undergoing primary decompression with fusion compared to revision patients were more likely to answer yes to “feel better after surgery” (87.8% vs 73.8%, p=0.023), “undergo surgery again” (90.1% vs 76.2%, P=0.021) and “improvement in mental health” (47.7% vs 28.6%, p=0.03) at six months. There was no difference in either of these outcomes at 12 or 24 months. There was no difference between the groups ODI, EQ-5D, SF 12 scores at any time point. Patients undergoing primary vs revision decompression alone showed no difference in PROMs at any time point.

In a matched cohort, there appears to be no difference in improvement in PROMS between patients undergoing primary vs revision decompression, with or without fusion, at two year follow-up. This would suggest similar outcomes can be obtained in revision cases.

Prolonged length of stay (LOS) is a significant contributor to the variation in surgical health care costs and resource utilization after elective spine surgery. The primary goal of this study was to identify patient, surgical and institutional variables that influence LOS. The secondary objective is to examine variability in institutional practices among participating centers.

This is a retrospective study of a prospectively multicentric followed cohort of patients enrolled in the CSORN between January 2015 and October 2020. A logistic regression model and bootstrapping method was used. A survey was sent to participating centers to assessed institutional level interventions in place to decrease LOS. Centers with LOS shorter than the median were compared to centers with LOS longer than the median.

A total of 3734 patients were included (979 discectomies, 1102 laminectomies, 1653 fusions). The median LOS for discectomy, laminectomy and fusion were respectively 0.0 day (IQR 1.0), 1.0 day (IQR 2.0) and 4.0 days (IQR 2.0). Laminectomy group had the largest variability (SD=4.4, Range 0-133 days). For discectomy, predictors of LOS longer than 0 days were having less leg pain, higher ODI, symptoms duration over 2 years, open procedure, and AE (p< 0.05). Predictors of longer LOS than median of 1 day for laminectomy were increasing age, living alone, higher ODI, open procedures, longer operative time, and AEs (p< 0.05). For posterior instrumented fusion, predictors of longer LOS than median of 4 days were older age, living alone, more comorbidities, less back pain, higher ODI, using narcotics, longer operative time, open procedures, and AEs (p< 0.05). Ten centers (53%) had either ERAS or a standardized protocol aimed at reducing LOS.

In this study stratifying individual patient and institutional level factors across Canada, several independent predictors were identified to enhance the understanding of LOS variability in common elective lumbar spine surgery. The current study provides an updated detailed analysis of the ongoing Canadian efforts in the implementation of multimodal ERAS care pathways. Future studies should explore multivariate analysis in institutional factors and the influence of preoperative patient education on LOS.

Degenerative lumbar spondylolisthesis (DLS) is a common condition with many available treatment options. The Degenerative Spondylolisthesis Instability Classification (DSIC) scheme, based on a systematic review of best available evidence, was proposed by Simmonds et al. in 2015. This classification scheme proposes that the stability of the patient's pathology be determined by a surgeon based on quantitative and qualitative clinical and radiographic parameters. The purpose of the study is to utilise machine learning to classify DLS patients according to the DSIC scheme, offering a novel approach in which an objectively consistent system is employed.

The patient data was collected by CSORN between 2015 and 2018 and included 224 DLS surgery cases. The data was cleaned by two methods, firstly, by deleting all patient entries with missing data, and secondly, by imputing the missing data using a maximum likelihood function. Five machine learning algorithms were used: logistic regression, boosted trees, random forests, support vector machines, and decision trees. The models were built using Python-based libraries and trained and tested using sklearn and pandas librairies. The algorithms were trained and tested using the two data sets (deletion and imputation cleaning methods). The matplotlib library was used to graph the ROC curves, including the area under the curve.

The machine learning models were all able to predict the DSIC grade. Of all the models, the support vector machine model performed best, achieving an area under the curve score of 0.82. This model achieved an accuracy of 63% and an F1 score of 0.58. Between the two data cleaning methods, the imputation method was better, achieving higher areas under the curve than the deletion method. The accuracy, recall, precision, and F1 scores were similar for both data cleaning methods.

The machine learning models were able to effectively predict physician decision making and score patients based on the DSIC scheme. The support vector machine model was able to achieve an area under the curve of 0.82 in comparison to physician classification. Since the data set was relatively small, the results could be improved with training on a larger data set. The use of machine learning models in DLS classification could prove to be an efficient approach to reduce human bias and error. Further efforts are necessary to test the inter- and intra-observer reliability of the DSIC scheme, as well as to determine if the surgeons using the scheme are following DLS treatment recommendations.

Resident involvement in the operating room is a vital component of their medical education. Conflicting and limited research exists regarding the effects of surgical resident participation on spine surgery patient outcomes. Our objective was to determine the effect of resident involvement on surgery duration, length of hospital stay and 30-day post-operative complication rates.

This study was a multicenter retrospective analysis of the prospectively collected American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database. All anterior cervical or posterior lumbar fusion surgery patients were identified. Patients who had missing trainee involvement information, surgery for cancer, preoperative infection or dirty wound classification, spine fractures, traumatic spinal cord injury, intradural surgery, thoracic surgery and emergency surgery were excluded. Propensity score for risk of any complication was calculated to account for baseline characteristic differences between the attending alone and trainee present group. Multivariate logistic regression was used to investigate the impact of resident involvement on surgery duration, length of hospital stay and 30 day post-operative complication rates.

1441 patients met the inclusion criteria: 1142 patients had surgeries with an attending physician alone and 299 patients had surgeries with trainee involvement. After adjusting using the calculated propensity score, the multivariate analysis demonstrated that there was no significant difference in any complication rates between surgeries involving trainees compared to surgeries with attending surgeons alone. Surgery times were found to be significantly longer for surgeries involving trainees. To further explore this relationship, separate analyses were performed for tertile of predicted surgery duration, cervical or lumbar surgery, instrumentation, inpatient or outpatient surgery. The effect of trainee involvement on increasing surgery time remained significant for medium predicted surgery duration, longer predicted surgery duration, cervical surgery, lumbar surgery, lumbar fusion surgery and inpatient surgery. There were no significant differences reported for any other factors.

After adjusting for confounding, we demonstrated in a national database that resident involvement in surgeries did not increase complication rates, length of hospital stay or surgical duration of more routine surgical cases. We found that resident involvement in surgical cases that were generally more complexed resulted in increased surgery time. Further study is required to determine the relationship between surgery complexity and the effect of resident involvement on surgery duration.

Introduction

Patients with reduced lumbar spine mobility are at higher risk of dislocation after THA as their hips have to compensate for spinal stiffness. Therefore our study aimed to 1) Define the optimal protocol for identifying patients with mobile hips and stiff lumbar spines and 2) Determine clinical and standing radiographic parameters predicting high hip and reduced lumbar spine mobility.

Aims

The aims of the study were to determine the differences in spinopelvic mobility between a cohort of hip OA patients and a control group for the 1) standing to relaxed-seated and 2) standing to deep-seated task.

Adverse events (AEs) following spine surgery are very common. It is important to monitor the incidence of AEs to ensure that appropriate practices are implemented to minimise AEs and improve patient outcomes. The Spine Adverse Events Severity System (SAVES) is a validated AE recording tool specifically designed for spine surgery and the Orthopaedic Surgical Adverse Events Severity System (OrthoSAVES) is a similar tool intended for general orthopaedic surgery. The main objective was to prospectively collect AE data from spine surgery patients using SAVES and OrthoSAVES and compare their viability and applicability for use. The longterm objective is to enhance patient safety by tracking AEs with a view towards potentially changing future healthcare practices to eliminate the risk factors for AEs.

For a 10-week period in June-September 2015, three spine surgeons used SAVES to record AEs experienced by any elective spine surgery patients. In addition, a trained independent clinical reviewer with access to electronic records, medical charts, and allied health professionals (e.g. nurses, physioterhapists) used SAVES and OrthoSAVES to record AEs for the same patients. At discharge, the SAVES forms from the surgeons and SAVES and OrthoSAVES forms from the independent reviewer were collected and all AEs were recorded in a database.

In 48 patients, the independent reviewer recorded a total of 45 AEs (4 intra-operative, 41 post-operative), compared to the surgeons who recorded a total of 8 AEs (2 intra-operative, 6 post-operative) (P2) were recorded by both the independent reviewer and surgeons. OrthoSAVES had the capacity to directly record 3 additional AEs that had to be included in the “Other” section on SAVES.

SAVES and OrthoSAVES are valuable tools for recording AEs. Use of SAVES and OrthoSAVES has the potential to enhance patient care and safety by ensuring AEs are followed by the surgeon during their in-hospital stay and prior to discharge. Independent reviewers are more effective at capturing AEs following spine surgery, and thus, could be recruited in order to capture more AEs and maximise different complication diagnoses in alignment with proposed diagnosis-based funding models. The next step is to analyse AE data identified by the hospital discharge abstract to determine whether retrospective administrative coding can adequately record AEs compared to prospectively-collected AE data with SAVES/OrthoSAVES.

The Spine Adverse Events Severity System (SAVES) and Orthopaedic Surgical Adverse Events Severity System (OrthoSAVES) are standardised assessment tools designed to record adverse events (AEs) in orthopaedic patients. The primary objective was to compare AEs recorded prospectively by orthopaedic surgeons compared to trained independent clinical reviewers. The secondary objective was to compare AEs following spine, hip, knee, and shoulder orthopaedic procedures.

Over a 10-week period, three orthopaedic spine surgeons recorded AEs following all elective procedures to the point of patient discharge. Three orthopaedic surgeons (hip, knee, and shoulder) also recorded AEs for their elective procedures. Two independent reviewers used SAVES and OrthoSAVES to record AEs after reviewing clinical notes by surgeons and other healthcare professionals (e.g. nurses, physiotherapists). At discharge, AEs recorded by the surgeons and independent reviewers were recorded in a database.

AE data for 164 patients were collected (48 spine, 52 hip, 33 knee, and 31 shoulder). Overall, 98 AEs were captured by the independent reviewers, compared to 14 captured by the surgeons. Independent reviewers recorded significantly more AEs than surgeons overall, as well as for each individual group (i.e. spine, hip, knee, shoulder) (p2), but surgeons failed to record minor events that were captured by the independent reviewers (e.g. urinary retention and cutaneous injuries; AEs Grade 0.05). AEs were reported in 21 (43.8%), 19 (36.5%), 12 (36.4%), and five (16.1%) spine, hip, knee, and shoulder patients, respectively. Nearly all reported AEs required only simple or minor treatment (e.g. antibiotic, foley catheter) and had no effect on outcome. Two patients experienced AEs that required invasive or complex treatment (e.g. surgery, monitored bed) that had a temporary effect on outcome.

Similar complication rates were reported in spine, hip, knee, and shoulder patients. Independent reviewers reported more AEs compared to surgeons. These findings suggest that independent reviewers are more effective at capturing AEs following orthopaedic surgery, and thus, could be recruited in order to capture more AEs, enhance patient safety and care, and maximise different complication diagnoses in alignment with proposed diagnosis-based funding models.

Purpose: Knee dislocation, although very rare, remains a devastating injury with many complications because of the complex nature of this trauma. The best treatment for knee dislocation is yet to be determined. The purposes of the study were to describe our surgical method, to report our results and to compare them with those of other surgical reconstruction techniques for knee dislocation.

Method: Fifty-six (56) patients with knee dislocation underwent acute combined reparation and reconstruction using Ligament Advancement Reinforcement System (LARS) artificial ligament. Patients were divided in three different groups according to the follow-up period. Group 1 (G1) included patients with a follow-up between two and six months post-op, group 2 (G2) involved patients with a follow-up between six months and twenty-four (24) months and group 3 (G3) was composed of patients who had a follow-up between twenty-four (24) and ninety-one (91) months.

Results: There was a significant difference between G1 and G3 for the Lysholm score and for the posterior stability at 90o of flexion measured with the Telos.

Conclusion: The subjective and objective findings from our series are satisfactory and comparable to the results of other series of knee dislocations. Our findings suggest that with a follow-up at seven years, acute combined reparation and reconstruction with LARS ligaments is a valid alternative for the treatment of knee dislocation.