Design of a Printed Circuit Board for a Sensorless Three-Phase Brushless DC Motor Control System

The use of brushless motors has increased in recent years due to superior performance characteristics compared with alternatives. The operation of a brushless motor is dependent upon a separate controller which is often in the form of a printed circuit board. As such, the size and performance capability of the controller can restrict the performance of the overall motor control system so advancements of these controllers further the potential use of BLDC motors. This project outlines the design of a PCB based, sensorless motor controller for operation of a three-phase BLDC motor powered by a 24 V, high current external supply. Components used were selected to withstand an ambient temperature environment of 125 degrees C. The design for this PCB based motor control system was completed but fabrication and testing of the system was prevented by COVID-19 related restrictions that prohibited the use of necessary facilities and equipment. The detailed design including component selection, board layout, and software development is included in addition to a plan for fabrication and fundamental functional testing. Although no results are available for analysis to bring about any conclusions, a variety of design strategies and corresponding learnings hold the potential to be a source of valuable reference to the further study and development of future designs

The Impact of the Academic Progress Rating on the Retention and Recruiting Strategies of NCAA Division I Football Programs

In 2004, the National Collegiate Athletic Association (NCAA) adopted legislation that it hoped would help increase the graduation rates of student athletes. The Academic Progress Rating (APR), was designed to hold each individual athletic program accountable for keeping student athletes eligible and at the institution until the student athlete graduates. With this reform the NCAA attached land mark discipline measures for non compliance of the APR standards. The purpose of this study was to examine the impact that the APR has had on NCAA college football programs. Specifically, this study focused on assessing coaches and directors of football operations\u27 (DFOs) responses to questions regarding the issues of contention by football coaches and DFOs that lie within the APR legislation and how this legislation has changed their recruiting and retention strategies. The 234 DFOs and coaches that serve in that position at NCAA Division I institutions were chosen as subjects for this study. They were asked to complete a survey containing questions about how the APR has changed their program\u27s recruiting and retention strategy. In addition, they were asked how the APR has affected their program\u27s graduation rate, amount of resources they and their athletic department have dedicated to academics, and the amount of transfers they have coming into and leaving their program, due to the APR. These responses were then analyzed to see if there were any differences among BCS automatic bid conferences and non-BCS automatic bid conferences. The results indicated that there was no significant difference between BCS and non-BCS programs in terms of retention and recruiting strategies due to the APR legislation. However, results did indicate that 45.6% of Division I college football programs changed their recruiting strategy. Of the respondents, 56.3% are slightly less, less, or extremely less likely to recruit prospects that are potential discipline problems. In addition, 64.1% of football programs were slightly less, less, or extremely less likely to recruit academically challenged prospects. While 45.7% of programs said they were slightly less, less or extremely less likely to recruit special admittance prospects. In terms of retention, 48.6% of football programs indicated that they were slightly more, more, or extremely more likely to retain discipline problems due to the APR. When faced with a student athlete that has convicted a misdemeanor, 17.5% of football programs responded they were slightly more likely or more likely to retain the student athlete. Other results from this survey showed that 66% of football programs and 75.7% of athletic departments have increased either money or resources to their academic budgets because of the APR legislation. Responses also implied that 61.1% of football programs were slightly more likely, more, or were extremely more likely to monitor class attendance due to the APR legislation. The results also indicated that 83.5% of football programs feel they have graduated more student athletes since the inception of the APR. Additionally, 28.2% of football programs stated that they have more student athletes transferring out of their program than into the program.\u2

MEDICATION USE AND FALLS IN OLDER ADULTS: A PHARMACOEPIDEMIOLOGIC APPROACH

More than one-third of community-dwelling older adults fall each year. Falling is classified as a geriatric syndrome which has multiple contributing factors and an interaction between chronic predisposing diseases and impairments and acute precipitating insults. One potentially modifiable risk factor is medication use. While previous research has been conducted on medication-related falls, there are several gaps remaining in the literature, including the lack evidence on dose-response relationships across wide ranges of medication classes and falls as well as the frequent inability to address confounding by indication. Therefore, the overall purpose of this project was to determine—in a large, representative sample of community-dwelling older adults—associations between antihypertensive, anticholinergic, and antidepressant use and recurrent falls. First, we found no increased risk of recurrent falls in antihypertensive users compared to non-users, or those taking higher doses or for longer durations. Only those using a loop diuretic were found to have a modest increased risk of recurrent falls. In conclusion, antihypertensive use overall was not associated with recurrent falls after adjusting for important confounders. Loop diuretic use may be associated with recurrent falls and needs further study. Second, we found no statistically significant increased risk of recurrent falls in anticholinergic users, or those taking higher doses or for longer durations. In conclusion, increased point estimates suggest an association of anticholinergic use with recurrent falls, but the associations did not reach statistical significance. Future studies are needed to examine other measures of anticholinergic burden, and their associations with other outcomes such as cognitive function. Third, we found a statistically significant increased risk of recurrent falls in antidepressant users. An increased risk was also seen among those taking SSRIs, those with short duration of use, and those taking moderate doses. Among those with a history of falls/fracture at baseline, we found an increase in risk for any antidepressant use, but no increased risk was found in those without a history of falls/fracture. Taken together, the findings from this proposal will provide clinicians and researchers with clinically-relevant information on potential harmful outcomes associated with chronic medication therapy among older adults

Lower Extremity Injury After Return to Sports From Concussion: A Systematic Review

BACKGROUND: Recent studies have suggested increased rates of lower extremity (LE) musculoskeletal injury after a diagnosed concussion, although significant heterogeneity exists. PURPOSE: To examine the current body of research and determine whether there is an increased risk for LE musculoskeletal injury after a concussion and to identify populations at an increased risk. STUDY DESIGN: Systematic review; Level of evidence, 3. METHODS: A systematic review of current literature using MEDLINE and PubMed databases was performed. Keywords included concussion, athlete, lower extremity injury, and return to sport. Inclusion criteria required original research articles written in the English language examining the rate of LE injuries after a diagnosed concussion. RESULTS: A total of 13 studies involving 4349 athletes (88.1% male and 11.9% female; mean age, 19.8 years) met inclusion criteria. Athletes were classified as high school (46.1%), collegiate (17.0%), or professional (36.9%). Of the 13 studies, 4 demonstrated an increased risk of LE injury within 90 days of a diagnosed concussion (odds ratio [OR], 3.44; 95% CI, 2.99-4.42), and 6 revealed an elevated risk of injury within 1 year of concussion (OR, 1.85; 95% CI, 1.73-2.84). Increased risk was seen in professional (OR, 2.49; 95% CI, 2.40-2.72) and collegiate (OR, 2.00; 95% CI, 1.96-2.16) athletes compared with high school athletes (OR, 0.97; 95% CI, 0.89-1.05). A stepwise increase in risk of sustaining an LE injury was observed with multiple concussions, with increasing risk observed from ≥2 (OR, 2.29; 95% CI, 1.85-2.83) to ≥3 (OR, 2.86; 95% CI, 2.36-3.48) career concussions. CONCLUSION: An increased incidence of LE injuries was observed at 90 days and 1 year after the diagnosis of a concussion. Higher levels of competition, such as at the collegiate and professional levels, resulted in an increased risk of sustaining a subsequent LE injury after a diagnosed concussion. These results suggest an at-risk population who may benefit from injury prevention methods after a concussion. Future studies should focus on identifying which injuries are most common, during what time period athletes are most vulnerable, and methods to prevent injury after return to sports

Older, Heavier, Arthritic, Psychiatrically Disordered, and Opioid-Familiar Patients Are at Risk for Opioid Use After Medial Patellofemoral Ligament Reconstruction

Purpose: To investigate which factors predispose patients for prolonged opioid use after medial patellofemoral ligament (MPFL) reconstruction. Methods: A retrospective review of all patients who underwent MPFL reconstruction at a single institution between January 2013 and June 2020 was conducted. Opioid consumption before and after surgery was recorded and confirmed using Michigan Automated Prescriptions System monitoring program. Patients were classified into preoperative opioid users and nonusers. Risk factors for continued opioid use were assessed by collecting patient demographic variables, psychiatric history, number of previous patellar dislocations, and operative factors. Results: A total of 102 patients were included during the time frame of interest. Patients were on average 21.6 ± 8.5 years old with a mean body mass index of 28.2 ± 7.9. Thirty patients (29.0%) sustained \u3e10 dislocations preoperatively. Preoperative opioid use was present in 13 (12.7%) patients. Greater than 10 dislocations (odds ratio [OR] 5.00, 95% confidence interval [CI] 1.12-20.92) and psychiatric history (OR 3.33, 95% CI, 1.2-9.1; P = .016) significantly predicted opioid refills the first month after surgery. Risk factors for opioid refills at 2 to 12 months postoperatively included smoking (OR 4.50, 95% CI 1.13-17.96), preoperative opioid use (OR 7.32, 95% CI 1.88-28.47), psychiatric disorder (OR 3.77, 95% CI 2.3-6.2; P \u3c .001), age \u3e30 years (OR 7.03, 95% CI 3.63-13.61; P \u3c .001), and obesity (OR 2.68, 95% CI 1.40-5.14; P = .002). Compared with Outerbridge 0, a greater percentage of patients with Outerbridge 1 or 2 and 3 or 4 continued using opioids 2 to 12 months after surgery (OR 3.06, 95% CI 1.33-7.02; P = .006 and OR 2.86, 95% CI 1.24-6.59; P = .010, respectively). Conclusions: For patients undergoing MPFL reconstruction, preoperative opioid use, cartilage damage, age \u3e30 years, smoking history, body mass index \u3e30, and history of psychiatric disorder were found to be significantly associated with prolonged opioid use after surgery. Postoperative opioid refills in this cohort declined after 1 month. Level of Evidence: Level III, retrospective cohort study

High Return to Play Rate and Reduced Career Longevity Following Surgical Management of Athletic Pubalgia in National Basketball Association Players

PURPOSE: To assess the effects of surgical treatment of athletic pubalgia (AP) on game use and performance metrics in National Basketball Association (NBA) players. METHODS: A retrospective review of all NBA players who underwent surgical management for AP from 1996 to 2018 was performed. A matched control group was created for comparison. The index period was defined as the entire NBA season in which surgery occurred, including the corresponding offseason. Player demographics, use (games played, games started, and minutes per game) and performance (player efficiency rating) metrics were collected for all players. Statistical analysis was performed to compare data before and after return to play. RESULTS: Thirty players with a history of surgical management for AP were included in the final analysis. Following surgery for AP, NBA players were found to have a return to play (RTP) rate of 90.91% (30/33). The average RTP following surgery was 4.73 ± 2.62 months. Compared with control athletes, athletes in the AP group played significantly fewer seasons postinjury (4.17 ± 2.70 vs 5.49 ± 3.04 seasons, respectively; P = .02). During the first year following RTP, NBA players experienced significant reductions in game use and performance, both when compared with the year prior and matched control athletes (P \u3c .05). At 3-year follow-up, players continued to demonstrate significant reductions in game use (minutes per game, P \u3c .05) but not performance. CONCLUSIONS: Following surgical treatment of AP, NBA players demonstrated a high RTP rate, but shortened career. A short-term reduction in game use and performance metrics was found the year of return following surgery. However, 3-year follow-up performance metrics normalized when compared with healthy controls. STUDY DESIGN: Level III; retrospective case-control study

Age Significantly Affects Response Rate to Outcomes Questionnaires Using Mobile Messaging Software

PURPOSE: To investigate the demographic factors that influence time to respond (TTR), time to completion (TTC), and response rate when using a text messaging-based system and to determine the feasibility and applicability of mobile messaging-based services for collection of patient-reported outcomes among orthopaedic sports medicine patients. METHODS: On the day of surgery, patient mobile phone number was collected and the automated mobile messaging service (MOSIO, Seattle, WA) messaged patients for 10 ``days postoperatively. Patient visual analog scale (VAS) scores were collected 3 times daily, side effects were asked each evening, and Patient-Reported Outcomes Measurement Information System (PROMIS) Pain Interference (PI) Short Form was collected on postoperative day 3 and 7. RESULTS: A total of 177 patients were enrolled in the study. The overall response rate to the survey questions was 75.0%. For all patients, the average TTR of questions was 35.09 ± 12.57 minutes. The TTC was 2.75 ± 3.56 minutes for PROMIS-PI, 3.51 ± 1.26 minutes for VAS, and 3.80 ± 6.87 for side-effect questions. When patients were stratified into age groups, the youngest group, 16 to 32 years, had the greatest response rate of 85.2% and patients in the 49 to 59 years group had the lowest response rate of 68.4% and 69.1%, respectively (P \u3c .001). There was no significant difference in the TTR or TTC for VAS, PROMIS-PI, or side-effect questions when patients were stratified by age or sex groups (P \u3e .05). CONCLUSIONS: Collectively, all age groups successfully achieved a mean response rate of 75%; however, significantly lower response rates were observed for patients \u3e49 years old. Differences in age and sex did not impact the overall TTR or TTC for VAS, PROMIS-PI, or side-effect questions. Mobile-based applications present as an emerging opportunity to track postoperative outcome scores and reduce clinic survey load. LEVEL OF EVIDENCE: Case series, level of evidence IV

Worse Postoperative Outcomes and Higher Reoperation in Smokers Compared to Nonsmokers for Arthroscopic Rotator Cuff Repair

Introduction: Smoking impairs healing potential and is a significant risk factor for complications following orthopaedic surgeries. The purpose of this study was to determine if a cohort of former or current smokers at time of surgery met the minimally clinical important difference (MCID) for Patient-Reported Outcomes Measurement Information System Upper Extremity (PROMIS-UE), Depression (PROMIS-D), and Pain Interference (PROMIS-PI) scores in comparison to nonsmokers. Methods: A retrospective review of patients who underwent rotator cuff repair was performed. Patients who completed preoperative and 6-month postoperative PROMIS scores were included. The MCID was calculated using a distribution technique with a threshold of 0.5 standard deviations above the mean. A cohort of nonsmokers was compared to current/former smokers in terms of clinical outcomes and PROMIS scores. Results: A total of 182 patients, 80 current/former smokers and 102 nonsmokers, were included. Smokers had significantly more massive-sized tears and more reoperations (16.3% vs 5.9%,P=0.02). No differences were found in change in PROMIS scores, proportion meeting MCID for PROMIS scores, and retear rate. In the sub-analysis, 74 current/former smokers were matched to 74 nonsmokers. Smokers had lower change in PROMIS-UE (8.6±9.8 vs 12.3±10.0,P=0.007) and PROMIS-PI (-9.1±8.5 vs -12.8±10.1,P=0.03) postoperatively. Fewer met MCID for PROMIS UE postoperatively (60.3% vs 82.4%,P=0.003) and more had reoperations (16.2% vs 4.1%,P=0.02). Conclusion: Smokers or former smokers demonstrated smaller improvements in function, pain scores, and were less likely to meet MCID for PROMIS-UE when compared to nonsmokers after arthroscopic rotator cuff repair. Smokers were more likely to undergo reoperations within 6 months

Associating Social Determinants of Health With PROMIS CAT Scores and Health Care Utilization After ACL Reconstruction

BACKGROUND: The term social determinants of health (SDOH) refers to social and economic factors that influence a patient\u27s health status. The effect of SDOH on the Patient-Reported Outcomes Measurement Information System (PROMIS) computer adaptive test (CAT) scores and postoperative resource utilization in patients with anterior cruciate ligament reconstruction (ACLR) have yet to be thoroughly studied. PURPOSE: To investigate the impact SDOH have on PROMIS CAT outcomes and postoperative resource utilization in patients with ACLR. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: The electronic medical record was used to identify the SDOH for patients who underwent ACLR by 1 of 3 sports medicine fellowship-trained orthopaedic surgeons between July 2017 and April 2020. PROMIS CAT measures of Physical Function (PROMIS-PF), Pain Interference (PROMIS-PI), and Depression (PROMIS-D) were completed at the preoperative, 6-month postoperative, and 12-month postoperative time points. Postoperative health care utilization was recorded as well. Independent 2-group t tests and Wilcoxon rank-sum tests were used to analyze mean differences between patient groups based on SDOH. RESULTS: Two-hundred and thirty patients who underwent ACLR were included (mean age, 27 years; 59% male). Compared with White patients, Black patients were represented more frequently in the lowest median household income (MHI) quartile (63% vs 23%, respectively; P \u3c .001). White patients were represented more frequently in the highest area deprivation index (ADI) quartile when compared with Black patients (67% vs 12%, respectively; P = .006). Significantly worse PROMIS-PF, PROMIS-PI, and PROMIS-D scores at all 3 time points were found among patients who were Black, female, smokers, and in the lower MHI quartiles, with higher ADI and public health care coverage. In terms of resource utilization, Black patients attended significantly fewer postoperative physical therapy visits when compared with their respective counterparts. Those in the lower MHI quartiles attended significantly fewer postoperative imaging encounters, and female patients attended significantly more postoperative virtual encounters than male patients. CONCLUSION: Specific SDOH variables, particularly those that reflect racial and socioeconomic disparities, were associated with differences in postoperative health care utilization and ACLR outcomes as measured by PROMIS CAT domains

Reduced Career Longevity but Return to Baseline Performance After Arthroscopic Shoulder Labral Repair in National Hockey League Players

PURPOSE: To investigate the impact of arthroscopic shoulder labral repair without shoulder instability on career longevity, game use, and performance in National Hockey League (NHL) athletes. METHODS: A retrospective review of all NHL players who underwent arthroscopic shoulder labral repair from 2004 to 2020 was performed. A 2:1 matched control group was used for comparison. Controls were matched by age, body mass index, position, and experience prior to the index year. Demographic characteristics, game use, and performance metrics were collected for all athletes. Statistical analysis examined game use and performance both at 1-year and 3-year follow-up compared with one season before injury. RESULTS: Twenty-nine players who underwent arthroscopic shoulder labral surgery returned to play (100%) and were matched with 55 control players. The operative cohort experienced shorter careers compared with controls (4.4 ± 3.1 vs 6.0 ± 3.6 seasons, P < .05). After one season, injured players experienced significant reductions in goals per 60 (0.6 ± 0.4 vs 0.8 ± 0.5, P = .013), points per 60 (1.5 ± 0.9 vs 2.0 ± 0.9, P = .001), and shooting percentage, (8.5 ± 5.8 vs 10.5 ± 5.2, P = .02) compared with the year prior. The reduction in goals (0.6 ± 0.4 vs 0.8 ± 0.5, P = .01) and shooting % (8.5 ± 4.7 vs 10.5 ± 5.2, P = .04) persisted at 3 years. Compared with controls, the surgical group experienced significant reductions at one season postindex in percentage of goals, assists, points per 60, and shooting percentage. Only the reduction in goals per 60 persisted at 3 seasons postindex. CONCLUSIONS: Following return to play after arthroscopic shoulder labral repair, NHL players demonstrated reduced career longevity compared with healthy controls. Players exhibited significant reductions in game use and performance at one season after injury but returned closer to baseline after 3 seasons. LEVEL OF EVIDENCE: Level III; retrospective case control