A Retrospective Comparative Study of Long-Term Outcomes Following Cervical Total Disc Replacement Versus Anterior Cervical Discectomy and Fusion.

Introduction The traditional treatment for patients with radiculopathy and myelopathy caused by degenerative disc disease was anterior cervical discectomy and fusion (ACDF). However, a documented complication of ACDF is adjacent segment degeneration (ASD). An alternative that was developed was total disc replacement (TDR). The aim of this study was to determine and compare the short- and medium-to-long-term outcomes after a TDR or ACDF. Methods A retrospective review of 154 patients who had single and two-level ACDFs and 90 TDRs performed by a single surgeon between 2011 and 2017 was conducted. Parameters for comparisons include both radiological evaluation and patient-reported outcome measures (PROMS) at six weeks, one year, and two years postoperatively. The Neck Disability Index (NDI) and the visual analogue scale (VAS) for neck and arm pain are used to evaluate pain, function, patient satisfaction, and overall clinical success. Results TDR and ACDF showed significant improvement in NDI and VAS when compared to pre- and post-operatively at both six weeks (p<0.05 & P=0.032, respectively) and two years (p<0.05 & 0=0.026, respectively). TDR vs. ACDF showed no significant difference (p<0.05). VAS scores after ACDF showed improvement from 13.41 to 3.94 at two years (p<0.001). TDR showed similar scores of 12.5 to 3.55 (p<0.001). The radiological fusion rate at 12 or 24 months showed no significant difference between the two groups. There were two cases that required re-operation after ACDF (1.2%), and two that required TDR (2.2%). Conclusion Both TDR and ACDF lead to clinically significant improvements in pain and function scores. We did not find a statistically significant difference in NDI and VAS in the neck and arm. The results are in agreement with others' assessments of these two treatment modalities. Our conclusions supplement the literature about these operative options for degenerative disc disease of the cervical spine and are a useful addition to the armamentarium in the assessment of patients with degenerative pathology of the c-spine.

The Incidence, Distribution and Clinicopathology of Missed Colorectal Cancer After Diagnostic Colonoscopy.

BACKGROUND: Colonoscopy does miss some lesions that may be later diagnosed as post-colonoscopy colorectal cancers (PCCRCs). We evaluated the rate of PCCRCs in a cohort of our patients. METHODS: The data of patients diagnosed with first primary colorectal cancers (CRCs) between July 2014 and June 2017 were analyzed. Colorectal cancers were considered to be missed if they occurred among patients who have had an index colonoscopy between 7 and 36 months prior to their diagnosis. The incidence of missed lesions and the distribution of such lesions in the large bowel are presented. RESULTS: In the study, 399 of the total 541 patients whose CRCs were diagnosed by colonoscopy were included. The median age of the patients (213 males and 186 females) was 75.3 (32.4-82.1) years. Seven patients with diagnosis of primary CRCs had undergone index colonoscopy between 7 and 36 months prior to their diagnostic colonoscopy. Therefore, the PCCRC rate in this cohort was 1.8% (7/399 × 100). The mean time interval between the false negative colonoscopy (index colonoscopy) and diagnostic colonoscopy was 18.7 (9.1- 34.9) months. Missed CRCs were located in the ascending (2), transverse (1), descending (1), and sigmoid colon (2) and in the rectum (1). CONCLUSION: Our PCCRC rate was 1.8%, which is lower than the usually reported rate.

Restarting Elective Orthopaedic Surgery During the COVID-19 Pandemic: Lessons Learned.

Introduction  Coronavirus disease 2019 (COVID-19) resulted in postponing non-emergency elective surgeries beginning in April 2020. Our hospital successfully restarted elective orthopaedic surgery during the pandemic to help improve the quality of life of patients with chronic disabilities.  This study describes the development of local protocols and pathways to allow for a safe restart of elective orthopaedic surgery in a COVID-19-free 'green' site. It includes the morbidity and mortality outcomes of those patients who underwent non-emergency orthopaedic operations during this time.  Methods  This is a prospective cohort study over an eight-week period evaluating 104 patients undergoing non-emergency orthopaedic procedures through a COVID-19-free surgical pathway. The primary outcome measure was 14-day postoperative mortality. The main secondary outcome measures were the development of a COVID-19 infection in the hospital and 14 days postoperatively as well as the need for intensive care unit admissions.  Results  No patients developed a COVID-19 infection. There were no intensive care unit admissions or postoperative deaths during our study time frame. There was no statistical difference seen for age (< 70 or > 70), gender, body mass index, or American Society of Anesthesiologists (ASA) grades in the development of postoperative complications.  Conclusions  This study describes a roadmap to setting up a protocolised elective operating service for orthopaedic surgery. It has shown that standardised protocols in a COVID-19-free 'green' site, preoperative COVID-19 testing, and adherence to national guidelines on self-isolation can help prevent developing COVID-19 infection postoperatively and reduce the risk of postoperative mortality.

Climatic drivers of hemispheric asymmetry in global patterns of ant species richness.

Although many taxa show a latitudinal gradient in richness, the relationship between latitude and species richness is often asymmetrical between the northern and southern hemispheres. Here we examine the latitudinal pattern of species richness across 1003 local ant assemblages. We find latitudinal asymmetry, with southern hemisphere sites being more diverse than northern hemisphere sites. Most of this asymmetry could be explained statistically by differences in contemporary climate. Local ant species richness was positively associated with temperature, but negatively (although weakly) associated with temperature range and precipitation. After contemporary climate was accounted for, a modest difference in diversity between hemispheres persisted, suggesting that factors other than contemporary climate contributed to the hemispherical asymmetry. The most parsimonious explanation for this remaining asymmetry is that greater climate change since the Eocene in the northern than in the southern hemisphere has led to more extinctions in the northern hemisphere with consequent effects on local ant species richness.