A Global Perspective of Mentorship in Medical Schools: Systematic Review from 2014 to 2019.

Formal mentorship programs afford medical students research involvement, career guidance, and personal and professional development. We reviewed a total of 36 studies on mentorship in medical schools, 17 of which are from the United States (US) and 19 from outside the US. This descriptive study has determined the most common mentorship models used in medical schools both in the United States and internationally. Despite variance between programs, medical students in the US and worldwide prefer highly invested mentors with strong interpersonal skills. We concluded that both US and international mentorship provide crucial professional development for students; however, US-based mentorship is more focused on providing experience within individual specialties. More studies on current mentorship practices in medical schools are required to ensure that the diverse international medical education community is better represented.

Seatbelts Save Lives, and Spines, in Motor Vehicle Accidents: A Review of the National Trauma Data Bank in the Pediatric Population.

STUDY DESIGN: Database study. OBJECTIVE: The purpose of this study was to use a large, nationwide database to determine prevalence of pediatric spine fractures in the United States, associated injuries, mechanisms of injury (MOI), use of safety devices, and mortality rates. SUMMARY OF BACKGROUND DATA: Spinal fractures account for 1% to 2% of pediatric injuries. However, they are associated with significant comorbidities and complications. Motor vehicle accidents (MVAs) are most responsible for increased incidence observed. METHODS: Retrospective review of National Trauma Data Bank between 2009 and 2014 (analysis in 2019) for all vertebral fractures in patients under 18 years of age. Subanalysis included those in MVAs where protective device use data were available. Patient demographics, MOI, geographical and anatomical region of injury, concomitant musculoskeletal/organ injury, protective device usage, hospital length of stay, surgical procedures, and mortality were all analyzed. RESULTS: A total of 34,563 patients with 45,430 fractured vertebrae included. Median age was 15 years. Most fractures (63.1%) occurred in patients aged 15 to 17 years, most frequent MOI was MVA (66.8%), and most common geographic location was the South (38%). Males sustained more spine fractures than females, overall (58.4% vs. 41.6%; P < 0.001) and in MVAs (54.4% vs. 45.6%; P < 0.001). Those in MVAs wearing seatbelts had lower odds of cranial (29.6% vs. 70.4%; odds ratio [OR] = 0.85, 95% confidence interval [CI]: 0.82-0.89; P < 0.001) and thoracic (30.1% vs. 69.9%; OR = 0.88, 95% CI: 0.84-0.91; P < 0.001) organ injury, multivertebral (30% vs. 70%; OR = 0.78, 95% CI: 0.73-0.83; P < 0.001) and concomitant nonvertebral fractures (30.9% vs. 69.1%; OR = 0.89, 95% CI:0.73-0.83; P < 0.001), and 21% lower odds of mortality (29.3% vs. 70.7%; OR = 0.79, 95% CI: 0.66-0.94; P = 0.009). Over 70% of drivers were not restrained during MVA, with majority of seatbelt violations incurred by males, ages 15 to 17, in the South. CONCLUSION: Over 60% of pediatric spinal fractures occur in children aged 15 to 17 years, coinciding with the beginning of legal driving. MVA is the most common cause and has significant association with morbidity/mortality. Nearly two- thirds pediatric spinal fractures sustained in MVAs occurred without seatbelts. Absence of seatbelts associated with >20% greater odds of mortality. Ensuring new drivers wear protective devices can greatly reduce morbidity/ mortality associated with MVA.Level of Evidence: 3.

Predicting Autologous Hamstring Graft Diameter in the Pediatric Population Using Preoperative Magnetic Resonance Imaging and Demographic Data.

BACKGROUND: Anterior cruciate ligament (ACL) reconstruction before 18 years of age has been linked with an increased risk for failure when the graft diameter is <8 mm. PURPOSE/HYPOTHESIS: The purpose of this study was to determine whether autologous hamstring graft size can be reliably predicted with the use of preoperative magnetic resonance imaging (MRI) measurements. We hypothesized that the average of multiple axial cross-sectional area MRI measurements for the semitendinosus tendon and gracilis tendon would alone accurately predict graft diameter. Additionally, factoring in specific demographic data to the MRI cross-sectional areas would provide a synergistic effect to the accuracy of graft diameter predictions. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: We retrospectively reviewed 51 pediatric patients undergoing ACL reconstructions (age <18 years) performed using either a quadruple-strand semitendinosus tendon or combined double-bundle semitendinosus tendon-gracilis tendon autograft. Preoperative axial MRI scans at multiple points along the craniocaudal axis-specifically, at the level of the joint line, 3 cm cephalad to the medial tibial plateau, and 5 cm cephalad to the medial tibial plateau-were used to determine the combined cross-sectional area of the semitendinosus and gracilis tendons. The MRI measurements were analyzed using Pearson correlation as well as regression analysis to evaluate strength of correlation between measurements. Binomial linear regression was used to analyze the same predictive variables assessed by multiple regression. RESULTS: The predicted graft diameter was within 0.5 mm of the intraoperative graft size in 37 of 51 (72.5%) patients and within 1 mm of the intraoperative graft size in 49 of 51 (96.1%). With the addition of demographics, the accuracy of predictions increased to 78.4% within 0.5 mm and 98% within 1 mm of the actual graft size. Additionally, 38 of 42 patients whose true graft diameter was ≥8 mm were correctly classified, giving a sensitivity of 90.4%. For those whose true graft diameter was <8 mm, 8 of 9 patients were correctly classified; therefore, the specificity was 88.9%. CONCLUSION: The results of our study suggest that taking the average of multiple preoperative MRI measurements can be used to accurately predict autologous hamstring graft size when approaching pediatric patients undergoing ACL reconstruction.

Are All Hardware Removals Equal?

The objective of this study is to report operative time and associated complications of six types of implants and to determine if surgeons are adequately compensated. Hardware removals were analyzed from 2014-2019. Implants were flexible nails, intramedullary rigid nails, long plates, screw(s), single guided-growth plates, and multiple guided-growth plates. Patient demographics, operative time, blood loss, complications, and relative value units (RVU)/min were collected. RVU/min was used to maximize rate. In total, 392 patients were analyzed. Long plate removals took significantly longer than screw removal, therefore RVU/min was significantly lower (p < 0.001). Long plate removals also took significantly longer, and RVU/min was significantly lower compared to guided-growth plate removal (p < 0.001). Intramedullary nails took significantly longer compared to flexible nails, nearly double the RVU/min (p = 0.02). The results from this study indicate that the RVU/ minute for these six different types of implant removals are not equal. Surgeons can use this data to set up their schedule to ensure maximum utilization. (Journal of Surgical Orthopaedic Advances 30(1):020-023, 2021).

Demographic Analysis of Pedicle Diameter, and Estimated Pedicle Screw Length of the Lumbar Spine in a Diverse Population.

BACKGROUND: Recent literature confirms the importance of understanding the variability in pedicle morphology among races. These studies suggest that more detailed and reliable measurements of pedicles should be undertaken. However, there is limited data on average pedicle diameters (PDs) or estimated pedicle screw lengths (EPSLs) between diverse racial populations. We sought to determine the differences in PD and EPSL in the lumbar spine between various races: "Asian," "Black," "White," and "Hispanic" to aid in perioperative planning during instrumented spinal fusion. METHODS: Axial cuts of 404 patients were inspected to obtain their transverse outer cortical PD as measured through the isthmus, and EPSL by measuring the posterior entry point at the longest distance, which perpendicularly transected the measured isthmic diameter, to the anterior vertebral cortex from L1 to L5. We examined the average PD and PD range at each level for each race. To determine the significance, we used a mixed analysis of variance and a post hoc analysis. RESULTS: In this retrospective chart review the races were found to be significantly different in PD and EPSL (P < .001). Post hoc analysis using Dunn-Bonferroni correction showed that Asians had significantly smaller PDs than Blacks and Whites (P < .002 and P < .014, respectively). The White and Hispanic population had significantly longer EPSLs when compared to Blacks and Asians from L1 to L5 (P < .01). CONCLUSIONS: This study demonstrates that there are significant differences in pedicle morphology among races that must be taken into consideration when inserting pedicle screws during lumbar spinal fusion. Knowledge of these differences is of the utmost importance in order to limit complications while improving fixation. LEVEL OF EVIDENCE: 3. CLINICAL RELEVANCE: Pedicle morphology is variable between races and understanding these differences is important for the safe placement of pedicle screws.

Factors Predicting Hemodynamic Interventions During Inpatient Admission After Shoulder Arthroplasty.

BACKGROUND: We sought to identify the influence of shoulder arthroplasty (SA) type (primary anatomic, primary reverse, revision) and indication (fracture, arthritis) on the risk of postoperative packed red blood cell transfusion (pRBCT) and intravenous fluid bolus (IVFB). METHODS: Patients who underwent SA from 2013 through 2016 at our institution were categorized into four groups: primary anatomic (pTSA; N = 298), primary reverse (pRTSA; N = 292), revision (RevSA; N = 133), and shoulder arthroplasty for fracture (SAF; N = 58). Basic demographics, intraoperative metrics, preoperative lab values, and postoperative interventions (pRBCT and IVFB) were retrieved from electronic records. RESULTS: There were 781 SAs, of which 176 cases involved at least one postoperative intervention: pRBCT (6.3%) or IVFB (18.8%). Compared to pTSA, the odds of pRBCT in pRTSA, revSA, and SAF were: 3.0 (95% CI 0.9-10.0), 3.4 (95% CI 0.9-2.7), and 8.6 (95% CI 2.2-32.9), respectively. Independent risk factors for pRBCT included increasing age (p = 0.003), underweight body mass index (p = 0.019), Charlson Comorbidity Index ≥ 3 (p = 0.002), inpatient discharge to higher level of care (p = 0.011), estimated blood loss (p = 0.003), and preoperative hemoglobin (p ≤ 0.001). Also, compared to pTSA, the odds for IVFB in pRTSA, revSA, and SAF were: 2.8 (95% CI 1.7-4.6), 2.2 (95% CI 1.2-4.0), and 4.7 (95% CI 2.2-9.9), respectively. Other independent risk factors for IVFB included female sex (0.002), CCI ≥ 3 (p = 0.017), and operative time (p = 0.047). CONCLUSION: Shoulder arthroplasty for fracture is an independent risk factor for higher risk of postoperative pRBCT and IVFB.

Surgeon volume affects short- and long-term surgical outcomes in idiopathic scoliosis.

STUDY DESIGN: Retrospective review of New York Statewide Planning and Research Cooperative System (SPARCS) Inpatient Database. OBJECTIVE: To identify the differences in short- and long-term complications, following long-segment pediatric spinal fusion in idiopathic scoliosis surgery, between surgeons with low versus high annual surgical volume. Spinal deformity surgery is complex and requires significant training and repetition to master. Surgeon and hospital volume have been shown to correlate with outcomes following cervical and lumbar spine surgery. However, there is limited literature regarding the impact of surgeon volume on long-term outcomes following pediatric idiopathic spinal deformity correction. METHODS: This is a retrospective review of the SPARCS inpatient database from 2004 to 2013 of pediatric patients who underwent idiopathic scoliosis surgery. Surgeons were stratified into high (> 15 cases/year)- and low (≤ 15 cases/year)-volume cohorts by aggregating all cases completed over the study period until 50% of the total cases were captured above and below an average case per-year threshold. This threshold occurred at 15 cases/year. Short-term and long-term readmission and medical/surgical complications were collected. Multivariate logistic regression models assessed the risk of short- and long-term complications between cohorts. RESULTS: 3910 pediatric patients underwent a primary arthrodesis from a total of 223 surgeons. More high-volume surgeons operated at academic teaching hospitals (p < 0.001), used a combined AP surgical approach (p < 0.001), and fewer utilized rhBMP (p < 0.001). High-volume surgeons had shorter lengths of stay (p < 0.001). Low-volume surgeons had increased odds of inpatient surgical complications (OR 1.55, 95% CI 1.00-2.45). Low-volume surgeons had increased odds of revision at 5 and 10 years (5 years. OR 1.56, 95% CI 1.05-2.31; 10 years. OR 1.59, 95% CI 1.09-2.31). Low-volume surgeons had increased odds of implant malfunction at 10 years (OR 1.81, 95% CI 1.15-2.86). CONCLUSIONS: High-volume surgeons had decreased odds of short- and long-term complications compared to low volume when performing primary spinal arthrodesis in idiopathic scoliosis. Low-volume surgeons experienced significantly greater odds of inpatient surgical complications, as well as increased risk of revision during long-term follow-up with a significantly increased risk of implant malfunction at 10 years post-operatively. LEVEL OF EVIDENCE: Level III.