The Hoffmann parallax: a prospective study to determine the benefit of Hoffmann's sign.

Background: Degenerative cervical myelopathy (DCM) is the most common cause of age-related spinal cord dysfunction worldwide. Despite the widespread use of provocative physical exam maneuvers in the workup of DCM, the clinical significance of Hoffmann's sign is controversial. Objective: The purpose of this study was to prospectively assess the diagnostic performance of Hoffmann's sign for DCM in a cohort of patients treated by a single spine surgeon. Materials & Methods: Patients were divided into two groups based on the presence of a Hoffmann sign on physical examination. Advanced imaging studies were independently reviewed by four raters for confirmation of a diagnosis of cervical cord compression. Prevalence, sensitivity, specificity, likelihood, and relative risk ratios for the Hoffmann sign were calculated, with subsequent Chi-square and receiver operator characteristic (ROC) analysis to further characterize correlative findings. Results: Fifty-two patients were included - of whom, thirty-four (58.6%) patients presented with a Hoffmann sign, and eleven (21.1%) patients demonstrated cord compression on imaging. The Hoffmann sign demonstrated a sensitivity of 20% and a specificity of 35.7% (LR = 0.32; 0.16-1.16). Chi-square analysis revealed that imaging findings positive for cord compression were proportionally greater for patients lacking a Hoffmann sign than those with a confirmed Hoffmann sign (p =0.032) ROC analysis demonstrated that a negative Hoffmann sign performed moderately well in predicting cord compression (AUC.721; p =0.031). Conclusions: The Hoffmann sign is an unreliable marker for cervical cord compression, and the lack of a Hoffmann sign may be more predictive of cervical cord compression.

Diversity in Orthopaedic Surgery Residencies Based on Allopathic Medical School Affiliation.

Orthopaedic surgery is one of the most competitive and least diverse specialties in medicine. Affiliation of an orthopaedics with an allopathic medical school impacts research opportunities and early exposure to clinical orthopaedics. The purpose of this study is to examine the potential effect allopathic medical school affiliation has on orthopaedic surgery resident demographics and academic characteristics. Methods: All 202 Accreditation Council for Graduate Medical Education (ACGME)-accredited orthopaedics programs were divided into 2 groups: Group 1 consisted of residency programs without an affiliated allopathic medical school, and Group 2 consisted of programs with an affiliated allopathic medical school. Affiliations were determined by cross-referencing the ACGME residency program list with the medical school list published by Association of American Medical Colleges (AAMC). Program and resident characteristics were then compiled using AAMC's Residency Explorer including region, program setting, number of residents, and osteopathic recognition. Resident characteristics included race, gender, experiences (work, volunteer, and research), peer-reviewed publications, and US Medical Licensing Examination Step 1 scores. Results: Of the 202 ACGME-accredited orthopaedics residencies, Group 1 had 61 (30.2%) programs, and Group 2 had 141 (69.8%) programs. Group 2 had larger programs (4.9 vs. 3.2 resident positions/year; p < 0.001) and 1.7 times the number of residency applicants (655.8 vs. 385.5; p < 0.001). Most Group 2 residents were allopathic medical school graduates, 95.5%, compared with 41.6% in Group 1. Group 1 had 57.0% osteopathic medical school graduates, compared with 2.9% in Group 2. There were 6.1% more White residents in Group 1 residencies (p = 0.025), and Group 2 residencies consisted of 3.5% more Black residents in relation to Group 1 (p = 0.03). Academic performance metrics were comparable between the 2 groups (p > 0.05). Conclusion: This study demonstrated that candidates who successfully match into an orthopaedic surgery residency program achieve high academic performance, regardless of whether the program was affiliated with an allopathic medical school. Differences may be influenced by increased representation of minority faculty, greater demand for allopathic residents, or stronger emphasis on promotion of diversity in those residency programs. Availability of Data and Material: Available on reasonable request. Level of Evidence: Level III. See Instructions for Authors for a complete description of levels of evidence.

Location variance of the great vessels while undergoing side-bend positioning changes during lateral interbody fusion.

Background: Minimally invasive lateral lumbar interbody fusion (LLIF) is an increasingly popular surgical technique that facilitates minimally invasive exposure, attenuated blood loss, and potentially improved arthrodesis rates. However, there is a paucity of evidence elucidating the risk of vascular injury associated with LLIF, and no previous studies have evaluated the distance from the lumbar intervertebral space (IVS) to the abdominal vascular structures in a side-bend lateral decubitus position. Therefore, the purpose of this study is to evaluate the average distance, and changes in distance, from the lumbar IVS to the major vessels from supine to side-bend right and left lateral decubitus (RLD and LLD) positions simulating operating room positioning utilizing magnetic resonance imaging (MRI). Methods: We independently evaluated lumbar MRI scans of 10 adult patients in the supine, RLD, and LLD positions, calculating the distance from each lumbar IVS to adjacent major vascular structures. Results: At the cephalad lumbar levels (L1-L3), the aorta lies in closer proximity to the IVS in the RLD position, in contrast to the inferior vena cava (IVC), which is further from the IVS in the RLD. At the L3-S1 vertebral levels, the right and left common iliac arteries (CIA) are both further from the IVS in the LLD position, with the notable exception of the right CIA, which lies further from the IVS in the RLD at the L5-S1 level. At both the L4-5 and L5-S1 levels, the right common iliac vein (CIV) is further from the IVS in the RLD. In contrast, the left CIV is further from the IVS at the L4-5 and L5-S1 levels. Conclusion: Our results suggest that RLD positioning may be safer for LLIF as it affords greater distance away from critical venous structures, however, surgical positioning should be assessed at the discretion of the spine surgeon on a patient-specific basis.

Benefits of an Orthopedic Education Research Collaborative: An Innovative Approach.

Background Graduate Medical Education (GME) research in orthopedic surgery is an important but underrepresented subject in the medical literature. It was unknown if orthopedic residency leaders were interested in a surgical education research collaborative (orthopedic collaborative). The objectives of this study were to assess the potential benefit of an orthopedic collaborative from orthopedic residency leaders and investigate the factors associated with the support of a research collaborative within a surgical subspecialty. Methodology An anonymous 19-question survey-based study was distributed through REDCap (Nashville, TN, USA) to orthopedic residency leaders in the United States, from July to October 2020. The main outcome was perceived benefit. Additional aspects included program characteristics, challenges in performing resident education research, and organizational issues such as authorship, frequency of study requests, and governance. Results Almost all orthopedic faculty leadership (99%, 73/74) stated that resident education and faculty development research projects would benefit from an orthopedic education research collaborative. In comparison to unsupportive respondents, younger age (P = 0.006), 15 or fewer years in practice (P = 0.04), and having 0 to 100 peer-reviewed publications (P = 0.047) were associated with support for an orthopedic collaborative. Conclusions Challenges related to survey-based study quality and generalizability at single institutions can benefit from multi-institutional collaboration to develop high-quality studies that capture a representative sample to support orthopedic surgery program development.

The use of innominate artery cannulation for antegrade cerebral perfusion in aortic dissection.

BACKGROUND: Direct cannulation of the innominate artery for selective antegrade cerebral perfusion has been shown to be safe in elective proximal aortic reconstructions. We sought to evaluate the safety of this technique in acute aortic dissection. METHODS: A multi-institutional retrospective review was undertaken of patients who underwent proximal aortic reconstruction for Stanford type A dissection between 2006 and 2016. Those patients who had direct innominate artery cannulation for selective antegrade cerebral perfusion were selected for analysis. RESULTS: Seventy-five patients underwent innominate artery cannulation for ACP for Stanford Type A Dissections. Isolated replacement of the ascending aorta was performed in 36 patients (48.0%), concomitant aortic root replacement was required in 35 patients (46.7%), of whom 7 had a valve-sparing aortic root replacement, ascending aorta and arch replacement was required in 4 patients (5%). Other procedures included frozen elephant trunk (n = 11 (14.7%)), coronary artery bypass grafting (n = 20 (26.7%)), and peripheral arterial bypass (n = 4 (5.3%)). Mean hypothermic circulatory arrest time was 19 ± 13 min. Thirty-day mortality was 14.7% (n = 11). Perioperative stroke occurred in 7 patients (9.3%). CONCLUSIONS: This study is the first comprehensive review of direct innominate artery cannulation through median sternotomy for selective antegrade cerebral perfusion in aortic dissection. Our experience suggests that this strategy is a safe and effective technique compared to other reported methods of cannulation and cerebral protection for delivering selective antegrade cerebral perfusion in these cases.