Reverse coronal deformity: use of robotic total knee arthroplasty for identification and correction.

BACKGROUND: Despite continued advances in techniques and implant designs, a population of patients who are dissatisfied after total knee arthroplasty (TKA) remains. During robotic-assisted arthroplasty, real-time intraoperative assessment of patient knee alignment is performed. Here, we assess the prevalence of an under-appreciated deformity, reverse coronal deformity (RCD), and the benefits of utilizing robotic-assisted knee arthroplasty to help correct this dynamic deformity. METHODS: A retrospective study evaluating patients undergoing robotic-assisted cruciate-retaining TKA was performed. Intraoperative measurements were obtained using tibial and femoral arrays to assess coronal plane deformity at full extension and at 90° flexion. RCD was defined as ≥ 2° varus in knee extension that reversed to ≥ 2° valgus in flexion, or vice-versa. Coronal plane deformity was then reassessed after robotic-assisted bony resection and implant placement. RESULTS: Of 204 patients that underwent TKA, 16 patients (7.8%) were found to have RCD, with 14 patients (87.5%) transitioning from varus in extension to valgus in flexion. The average coronal deformity was 7.75°, with a maximum of 12°. These improved to an average coronal change of 0.93° post-TKA. Final medial and lateral gaps were all balanced to within 1° in extension and flexion. Another 34 patients (16.7%) had ≥ 5° change in coronal plane deformity from extension to flexion (average 6.39°), however, did not experience a reversal of their coronal deformity. Outcomes were assessed with KOOS Jr. scores postoperatively. CONCLUSION: Computer and robotic assistance were utilized to demonstrate the prevalence of RCD. We also demonstrated accurate identification and successfully balancing of RCD utilizing robotic-assisted TKA. An increased awareness of these dynamic deformities could aid surgeons in proper gap balancing even in the absence of navigation and robotic-assisted surgery.

Multiligamentous Knee Injuries: Current Concepts Review.

Multiligamentous knee injuries (MLKI) are rare but devastating injuries that have a potential to cause long-term sequelae and significant morbidity. Frequently occurring concomitantly with knee dislocations (KD), MLKI have many risk factors that influence their incidence and treatment outcomes. Proper understanding of these risk factors can assist the surgeon with evaluation, surgical planning, and managing patient expectations both pre- and postoperatively. The purpose of this review is fourfold: (1) identify the risk factors and injuries associated with MLKI, (2) describe factors implicated in the treatment of MLKI, (3) report the effect of these risk factors on outcomes of MLKI, and (4) provide a brief insight into MLKI at our tertiary referral academic care center. This was a retrospective review of literature relevant to MLKI. Studies that described injuries, risk factors, treatment techniques, or outcomes associated with MLKI were included in our review. A total of 35 studies (consisting of level 3 and 4 evidence) published between 2009 and 2020 were found and included in our analysis. In addition, 25 patients who underwent treatment for MLKI at the University of Chicago Medical Center between December 2015 and December 2019 were included in our analysis. MLKI tend to occur in the younger male population. Increasing age, body mass index, and severity of the injury have been correlated with worse functional and patient-reported outcomes. Operative treatment is indicated for MLKI; however, timing and repair versus reconstruction is still debated, and is often decided on a patient by patient basis. Retrospective cohort studies have indicated that reconstruction may be favored; however, further more rigorous studies are needed to better characterize this finding. MLKIs are devastating injuries with significant variability in presentation, treatment, and outcome. Variations in these are largely attributable to the mechanism and severity of injury, timing, and surgeon preference. A holistic approach, and understanding of the present literature, is required to best optimize patient outcome.

Lower Extremity Stress Fractures in the National Basketball Association, 2013-2014 Through 2018-2019.

Background: Players in the National Basketball Association (NBA) are at risk for lower extremity stress fractures, partly because of the sport's high-intensity demand on the lower body. Purpose: To provide insight on the identification and management of potential risk factors associated with lower extremity stress fractures in NBA athletes. Study Design: Case series; Level of evidence, 4. Methods: A retrospective study was conducted using the NBA electronic medical record database for all players who were on an NBA roster for ≥1 game from the 2013-2014 through 2018-2019 seasons. Player characteristics, games missed, and treatment methodology were independently analyzed. Results were presented as incidence per 1000 player-games. Results: There were 22 stress fractures identified in 20 NBA players over the course of 6 years, with an average of 3.67 stress fractures per year and an incidence of 0.12 stress fractures per 1000 player-games. Most stress fractures occurred in the foot (17/22), and 45% (10/22) of stress fractures were treated surgically, with the most common site of operation being the navicular. On average, approximately 37 games and 243 days were missed per stress fracture injury. There was no significant difference in time to return to play between high-risk stress fractures treated operatively versus nonoperatively (269.2 vs 243.8 days; P = .82). Conclusion: The overall incidence of stress fractures in NBA players was 0.12 per 1000 player-games, and a high percentage of players returned to NBA activity after the injury. There was a relatively even distribution between high-risk stress fractures treated operatively and nonoperatively. When comparing high-risk stress fractures treated operatively to ones treated nonoperatively, no significant difference in average time to return to play in the NBA was found.

Diagnostic Value of MRI and Radiographs of the Knee to Identify Osteochondral Lesions in Acute Patellar Instability.

The purpose of this study was to define the diagnostic value of magnetic resonance imaging (MRI) and plain radiographs (X-ray [XR]) in identifying an osteochondral defect or loose body in patients undergoing operative treatment for patellar instability. A total of 87 patients treated operatively for patellar instability with medial patellofemoral ligament (MPFL) reconstruction between 2015 and 2019 were identified. Inclusion criteria were evidence of clinical patellar instability, preoperative XR and MRI studies, and concomitant diagnostic knee arthroscopy and MPFL reconstruction performed to address patellar instability. Patients were excluded if they had a history of prior procedure for patellar instability on the surgical knee, underwent MPFL reconstruction without concomitant diagnostic knee arthroscopy, or had an anterior cruciate ligament or posterior cruciate ligament deficient knee. Operative notes and arthroscopic images were reviewed to identify osteochondral or chondral injuries and loose bodies noted during diagnostic arthroscopy. The primary outcome was the identification of intra-articular loose bodies, chondral injury, or osteochondral defect on preoperative plain radiographs and MRI in patients with patellar instability. All MRIs were performed on a 3T MRI. The sensitivity and specificity of identifying loose bodies on MRI were 0.52 and 0.92 and on XR were 0.23 and 0.98, respectively. The sensitivity and specificity of identifying osteochondral lesions on MRI were 0.43 and 0.81 and on XR were 0.08 and 0.97, respectively. Of the 87 available reports, 45 (51%) described performing chondroplasty for Outerbridge grade II/III chondral lesions on diagnostic arthroscopy. In conclusion, MRI and XR are poorly sensitive at identifying loose bodies or osteochondral defects after patellar dislocations. The poor sensitivity of imaging studies must be considered when determining whether or not to recommend operative management to a patient with patellar instability. This is a Level IV, diagnostic study.

Playing Rule Article Eight Decreases the Rate of Sport Related Concussion in NFL Players Over Two Seasons.

OBJECTIVES: The objectives of this study were to determine if rule article 8 significantly reduced (1) the rate of concussions sustained by NFL players during regular season games, (2) the average games missed secondary to concussion injury, and (3) the number of players placed on the injury reserve for sport-related concussions (SRC). METHODS: This study was a retrospective review of all NFL players who were placed on the publically available injury reports for a concussion from the 2016-2017 to 2019-2020 regular seasons. Player's date of injury was cross-referenced with an absence of statistics from the respective games for which they were ruled out to ensure accuracy. With article 8 taking effect starting with the 2018-2019 season, players were assigned to a pre- or postrule cohort based on date of injury for purposes of injury rate comparison. Injury rates were calculated per 1000 athletic exposures (AE). Relative risk (RR) with 95% confidence intervals (CI) compared injury rates between the two cohorts. Average number of games missed and number of players placed on injury reserve (IR) per year were also calculated. Continuous variables were statistically compared using two-tailed t-test, while categorical variables were compared using Chi-squared test. Statistical significance was set at P ≤ 0.05. RESULTS: There was a 40% decrease in the SRC rate when comparing the post- to the pre-article-8 cohort (3.3 vs 5.5/1000 AEs, respectively; RR 0.60; 95% CI 0.50-0.73). There was no significant difference in average games missed per concussion or percentage of players placed on the IR due to SRC between the two cohorts. CONCLUSIONS: The rate of SRC over the past two NFL seasons following the enactment of playing rule article 8 has significantly decreased when compared with the two seasons prior. The average games missed per concussion and the number of players placed on the IR due to SRC has not significantly changed under playing rule article 8.

Frequency of overtime and consecutive games and their impact on injury rate in the National Hockey League (NHL).

OBJECTIVES: Ice hockey is a high-intensity contact sport that places athletes at an elevated risk for injury relative to other sports. The purpose of the current study was to analyze factors contributing to fatigue and decreased recovery time and their associations with injury incidence among professional athletes in the National Hockey League (NHL). METHODS: A retrospective review of all injuries suffered by NHL athletes during six consecutive seasons from 2013 to 2019 was performed. Team schedules were analyzed to assess (1) the number of instances with games on consecutive calendar days, (2) the number of overtime games, and (3) the number of overtime games within three calendar days of a previous overtime game. A Spearman's rank correlation coefficient was calculated from this data to assess the association between these factors and injury rates. RESULTS: In total, 4886 injuries were suffered by NHL players during the period of study, with the 2013-2014 regular season highest injury rate per 1000 athletic exposures (15.8). The lower body was the most frequently injured body area (25.0% of all injuries), followed by injuries to the upper body (23.7%). In an analysis of the number of overtime games and games on consecutive days and their relationships to injury rate, only overtime games within three calendar days and total injuries were found to have a significant association (ρ = 0.19, p = 0.01). CONCLUSION: The weak positive correlation between the number of overtime games within threedays of a previous overtime game and total injuries in professional ice hockey players suggests that overtime games played within a short period of time place athletes at increased risk for injury. Further studies are necessary to address this on an athlete-by-athlete level.

The new 'normal': Rapid adoption of telemedicine in orthopaedics during the COVID-19 pandemic.

BACKGROUND: Telemedicine provides a safe and effective means for the delivery of care by physicians amongst many subspecialties. Historically, orthopaedic practices in the United States have not widely utilized telemedicine for the delivery of orthopaedic care. As technology improves the adoption and utilization of telemedicine will likely grow, especially in light of the novel coronavirus (COVID-19) pandemic. Our study aims to assess patient and surgeon satisfaction and efficacy of telemedicine during a rapid adoption due to the global pandemic. METHODS: All patients who completed a telemedicine encounter (telephone or video) with an orthopaedic surgeon were contacted. Patients were individually contacted after their visit, and a standardized validated post-visit satisfaction survey was completed. Orthopaedic surgeons completed a standardized post-encounter survey after each visit. Pre-COVID-19 patient satisfaction data was used for comparison. RESULTS: Orthopaedic surgeons completed 612 telehealth encounters either via phone or video consultation between April 6, 2020 and May 22, 2020. 95% of patients rated both surgeon sensitivity to their needs and response to their concerns as 'good' or 'very good.' 93% of patients reported they would participate in a telemedicine encounter again. Surgeons reported high satisfaction with telemedicine encounters (80%, 86% phone and video respectively), and that 78.4% of the time a telemedicine encounter was successful in replacing an in-person visit. CONCLUSION: Patients and orthopaedic surgeons documented high levels of satisfaction with telehealth encounters during the novel coronavirus (COVID-19) pandemic. Telemedicine does not appear to be a replacement for all in-person clinic encounters, however, when used in the appropriate context demonstrated favourable results. LEVEL OF EVIDENCE: Level 4 Study.

Acute Hematogenous Osteomyelitis of the Scapula: A Case Report.

CASE: We present the case of a previously healthy 4-year-old boy with aggressive acute hematogenous osteomyelitis (AHO) of the scapula. Despite only 3 days of symptoms, he had a large abscess, prolonged bacteremia, and significant bony destruction. He required multiple debridements and intravenous antibiotics to control the infection but ultimately had full restoration of bony anatomy and normal function. CONCLUSIONS: Reported cases of AHO in the scapula are extremely rare. This case highlights the surgical approach to this problem and the importance of repeat advanced imaging and repeat debridements when clinically necessary.

Injury in the Women's National Basketball Association (WNBA) From 2015 to 2019.

PURPOSE: To provide an overview of the injuries suffered by Women's National Basketball Association (WNBA) athletes and to analyze the demographic data, injury rates, and games missed as a result of individual injuries. METHODS: Using publicly available data on WNBA player's injury history, we generated a database cataloguing the quantity, location, frequency, and longitudinal impact of injuries sustained during the WNBA regular season from 2015 to 2019. We analyzed the data using SPSS-25 data manipulation software to assess the number of injuries per athletic exposure. RESULTS: Lower-extremity injuries (n = 143, 73%) were the most common injury by body area and resulted in the greatest number of games missed (n = 1189, 88%). Lateral ankle sprains were the most frequent injury (n = 39, 20%), with a rate of 1.19 injuries per 1000 athletic exposures. Torn anterior cruciate ligaments (n = 18, 9.2%) were the most devastating, resulting in the greatest number of games missed (n=376, 28%). CONCLUSIONS: Our findings corroborate previous notions that lower-extremity injuries are the greatest source of injury in this population. Ankle injuries were the most frequent injury reported by pathology, while knee injuries carried the most long-term impact on games missed due to injury. LEVEL OF EVIDENCE: IV, Epidemiological study.

Brachial Plexus Palsy Because of Pavlik Harness Use: A Case Report.

CASE: A 2.5-month-old girl with bilateral hip dysplasia presented for orthopaedic evaluation and began treatment with a Pavlik harness. One month after the initiation of treatment, decreased use of the left upper extremity was noted, which was consistent with a brachial plexus palsy. The Pavlik harness was discontinued, and upper extremity function fully recovered within 8 weeks. CONCLUSIONS: The Pavlik harness is an effective treatment for hip dysplasia with a low-risk profile. This case serves to remind clinicians of the risk for upper extremity traction injury when a Pavlik harness is used in patients who are large for their chronological age.

Postnatal tendon growth and remodeling require platelet-derived growth factor receptor signaling.

Platelet-derived growth factor receptor (PDGFR) signaling plays an important role in the fundamental biological activities of many cells that compose musculoskeletal tissues. However, little is known about the role of PDGFR signaling during tendon growth and remodeling in adult animals. Using the hindlimb synergist ablation model of tendon growth, our objectives were to determine the role of PDGFR signaling in the adaptation of tendons subjected to a mechanical growth stimulus, as well as to investigate the biological mechanisms behind this response. We demonstrate that both PDGFRs, PDGFRα and PDGFRß, are expressed in tendon fibroblasts and that the inhibition of PDGFR signaling suppresses the normal growth of tendon tissue in response to mechanical growth cues due to defects in fibroblast proliferation and migration. We also identify membrane type-1 matrix metalloproteinase (MT1-MMP) as an essential proteinase for the migration of tendon fibroblasts through their extracellular matrix. Furthermore, we report that MT1-MMP translation is regulated by phosphoinositide 3-kinase/Akt signaling, while ERK1/2 controls posttranslational trafficking of MT1-MMP to the plasma membrane of tendon fibroblasts. Taken together, these findings demonstrate that PDGFR signaling is necessary for postnatal tendon growth and remodeling and that MT1-MMP is a critical mediator of tendon fibroblast migration and a potential target for the treatment of tendon injuries and diseases.

Risk of peritoneal dialysis catheter-associated peritonitis following kidney transplant.

OBJECTIVE: Peritoneal dialysis (PD) patients have equivalent or slightly better kidney transplant outcomes when compared to hemodialysis (HD) patients. However, given the risk for postoperative infection, we sought to determine the risk factors for PD catheter-associated infections for patients who do not have the PD catheter removed at the time of engraftment. METHODS: Demographic and outcomes data were collected from 313 sequential PD patients who underwent kidney transplant from 2000 to 2015. Risk factors for postoperative peritonitis were analyzed using logistical regression. RESULTS: Of 329 patients with PD catheters at transplant, 16 PD catheters were removed at engraftment. Of the remaining 313 patients, 8.9% suffered post-transplant peritonitis. On univariate analysis, patients with peritonitis were significantly more likely to have used the PD catheter or HD within 6 weeks after transplant. Multivariate analysis had similar findings, with increased risk for those using the PD catheter after transplant, with a trend for those who underwent HD only within 6 weeks of transplant. CONCLUSION: These results suggest that delayed graft function requiring any type of dialysis is associated with increased post-transplant peritonitis risk.

Oxidant-free conversion of primary amines to nitriles.

An amide-derived NNN-Ru(II) hydride complex catalyzes oxidant-free, acceptorless, and chemoselective dehydrogenation of primary and secondary amines to the corresponding nitriles and imines with liberation of dihydrogen. The catalyst system tolerates oxidizable functionality and is selective for the dehydrogenation of primary amines (-CH2NH2) in the presence of amines without α-CH hydrogens.