Optimization of Polycaprolactone and Type I Collagen Scaffold for Tendon Tissue Regeneration.

Introduction Collagen synthesis is vital for restoring musculoskeletal tissues, particularly in tendon and ligamentous structures. Tissue engineering utilizes scaffolds for cell adhesion and differentiation. Although synthetic scaffolds offer initial strength, their long-term stability is surpassed by biological scaffolds. Combining polycaprolactone (PCL) toughness with collagen in scaffold design, this study refines fabrication via electrospinning, aiming to deliver enduring biomimetic matrices for widespread applications in musculoskeletal repair. Methods Electrospinning employed four solutions with varied collagen and PCL concentrations, dissolved in chloroform, methanol, and hexafluoro-2-propanol. Solutions were combined to yield 60 mg/mL concentrations with different collagen/PCL ratios. Electrospinning at 12-14kV voltage produced scaffolds, followed by vacuum-drying. Collagen coating was applied to PCL and 15% collagen/PCL scaffolds using a 0.1% collagen solution. SEM characterized fiber morphology, tensile testing was conducted to determine the mechanical properties of the scaffold, and Fourier-transform infrared (FTIR) spectroscopy analyzed scaffold composition. Atomic force microscopy (AFM) analyzed the stiffness properties of individual fibers, and a finite element model was developed to predict the mechanical properties. Cell culture involved seeding human bone marrow mesenchymal stem cells onto scaffolds, which were assessed through Alamar Blue assay and confocal imaging. Results Various scaffolds (100% PCL, PCL-15% collagen, PCL-25% collagen, PCL-35% collagen) were fabricated to emulate the extracellular matrix, revealing collagen's impact on fiber diameter reduction with increasing concentration. Tensile testing highlighted collagen's initial enhancement of mechanical strength, followed by a decline beyond PCL-15% collagen. FTIR spectroscopy detected potential hydrogen bonding between collagen and PCL. A finite element model predicted scaffold response to external forces which was validated by the tensile test data. Cell viability and proliferation assays demonstrated successful plating on all scaffolds, with optimal proliferation observed in PCL-25% collagen. Confocal imaging confirmed stem cell integration into the three-dimensional material. Collagen coating preserved nanofiber morphology, with no significant changes in diameter. Coating of collagen significantly altered the tensile strength of the scaffolds at the macro scale. AFM highlighted stiffness differences between PCL and collagen-coated PCL mats at the single fiber scale. The coating process did not significantly enhance initial cell attachment but promoted increased proliferation on collagen-coated PCL scaffolds. Conclusion The study reveals collagen-induced mechanical and morphological alterations, influencing fiber alignment, diameter, and chemical composition while emphasizing scaffolds' vital role in providing a controlled niche for stem cell proliferation and differentiation. The optimization of each of these scaffold characteristics and subsequent finite element modeling can lead to highly repeatable and ideal scaffold properties for stem cell integration and proliferation.

Excellent 10-Year survivorship of robotic-arm-assisted unicompartmental knee arthroplasty.

Introduction: Robotic-arm-assisted unicompartmental knee arthroplasty (UKA) is an excellent solution for patients suffering from single-compartment knee arthritis. While outcomes tend to be favorable for UKAs, revision operations, commonly due to component malpositioning and malalignment resulting in accelerated wear, are a major concern. Intraoperative technologies, such as robotic assistance, can help better ensure that implants are positioned based on a patient's specific anatomy and mechanical physiology. However, long-term survivorship and patient-reported satisfaction with robotic-assisted UKAs are limited. Therefore, the purpose of this study was to assess the 10-year outcomes of patients who underwent robotic-arm-assisted unicompartmental knee arthroplasty. Specifically, we evaluated: 1) 10-year survivorships; 2) patient satisfaction scores; and 3) re-operations. Methods: From a single surgeon and single institution, 185 patients who had a mean age of 65 years (range, 39 to 92) and a mean body mass index of 31.6 (range, 22.4 to 39) at a mean of 10 years follow-up were evaluated (range, 9 to 11). For all patients, the same robotic-assistive device was utilized intraoperatively, and all patients underwent standardized physical therapy and received standardized pain control management. Then 10-year survivorships with Kaplan-Meir curves, patient satisfaction evaluations with a 5-point Likert scale, and re-operations were assessed as primary outcomes. Results: Overall implant survivorship was 99%, with only two patients requiring revision surgery. There was one patient who was converted to a total knee arthroplasty, while the other patient underwent polyethylene exchange at 5 weeks for an acute infection with successful implant retention. Overall, 97% of the patients were satisfied with their postoperative outcomes, with 81% of patients reporting being very satisfied. There were two other patients who required arthroscopic intervention: one to remove a cement loose body, the other to remove adhered scar from the fat pad and the anterior cruciate ligament. Conclusion: This study is one of the first to provide longer-term (mean 10-year) survivorship and patient-reported satisfaction outcomes for robotic-assisted UKA patients. These data show strong support for utilizing this surgical technique, as nearly all patients maintained their original prostheses and reported being satisfied after a mean of 10 years. Therefore, based on these results, we recommend the use of robotic assistance when performing UKAs.

Functional and radiographic results of anatomic total shoulder arthroplasty in the setting of subscapularis dysfunction: 5-year outcomes analysis.

BACKGROUND: Subscapularis management is a critical component to the success of anatomic total shoulder arthroplasty (TSA). Failure to heal the subscapularis can result in pain, weakness, loss of function, and revision. However, not all patients have poor outcomes. The purpose of this study is to compare patients with normal and dysfunctional subscapularis function following TSA in regard to (1) patient-reported outcome measures (PROMs); (2) range of motion (ROM) and strength; (3) achievement of minimal clinically important differences (MCIDs); and (4) specific functional internal rotation tasks. METHODS: A retrospective review of patients treated with TSA for osteoarthritis with a minimum 2-year follow-up was performed to identify patients with subscapularis dysfunction. Subscapularis dysfunction was diagnosed when any degree of weakness in internal rotation was detected on physical examination (positive belly press sign). These patients were case controlled matched on a 1:3 ratio to patients with normal subscapularis function based on age and sex. PROMs, measured active motion, revision rates, patient satisfaction, and postoperative radiographic findings were compared. Population-specific institutional anchor-based MCID values were used to compare the improvement in PROM. RESULTS: Of the 668 patients included, 34 patients (5.1%) demonstrated evidence of subscapularis dysfunction. Mean follow-up for the normal subscapularis function cohort was 63.4 ± 29.7 and 58.7 ± 26.8 for the dysfunctional subscapularis cohort. Patients with subscapularis dysfunction demonstrated significantly worse postoperative Simple Shoulder Test, Single Assessment Numerical Evaluation, visual analog scale (VAS) function, VAS pain, and American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) scores with higher rates of unsatisfactory results when compared to patients with normal subscapularis function. Abduction, elevation, internal rotation ROM, along with supraspinatus and external rotation strength were also significantly worse in the dysfunctional group. Similarly, these patients were more likely to have decreased ability to perform functional internal rotation tasks, with only 47% of the patients being able to reach the small of their back compared to 85% with normal subscapularis function. Radiographically, the dysfunctional cohort demonstrated higher rates of anterior subluxation (56% vs. 7%; P < .001) and glenoid loosening (24% vs. 5%; P = .004). Similarly, revision rates were significantly higher for patients with subscapularis dysfunction (8 patients, 23.5%). Nonetheless, the dysfunctional subscapularis cohort demonstrated improvements in VAS pain (4.0 ± 3.7) and ASES (46.4 ± 35.9) scores that exceeded MCID thresholds. CONCLUSION: Patients who develop subscapularis dysfunction after TSA have significantly worse PROMs, ROM, functional tasks of internal rotation, and radiographic outcomes, as well as increased rates of revision. Although patients show worse outcomes and high revision rates compared with their normal-functioning counterparts, these patients maintained improvement above MCID thresholds for pain and function at a mean 5-year follow-up.

Impact of humeral stem length on calcar resorption in anatomic total shoulder arthroplasty.

BACKGROUND: Use of standard-length anatomic total shoulder (TSA) humeral stems has been associated with high rates of medial calcar bone loss. Calcar bone loss has been attributed to stress shielding, debris-induced osteolysis, and undiagnosed infection. Short stem and canal-sparing humeral components may provide more optimal stress distribution and thus lower rates of calcar bone loss related to stress shielding. The purpose of this study is to determine whether implant length will affect the rate and severity of medial calcar resorption. METHODS: A retrospective review was performed on TSA patients treated with three different-length humeral implants (canal-sparing, short, and standard-length designs). Patients were matched 1:1:1 based on both gender and age (±4 years), resulting in 40 patients per cohort. Radiographic changes in medial calcar bone were evaluated and graded on a 4-point scale, from the initial postoperative radiographs to those at 3 months, 6 months, and 12 months. RESULTS: The presence of any degree of medial calcar resorption demonstrated an overall rate of 73.3% at one year. At 3 months, calcar resorption was observed in 20% of the canal-sparing cohort, while the short and standard designs demonstrated resorption in 55% and 52.5%, respectively (P = .002). At 12 months, calcar resorption was seen in 65% of the canal-sparing design, while both the short and standard designs had a 77.5% rate of resorption (P = .345). The severity of calcar resorption for the canal-sparing cohort was significantly lower at all time points when compared to the short stem (3 months, P = .004; 6 months, P = .003; 12 months, P = .004) and at 3 months when compared to the standard-length stem (P = .009). CONCLUSION: Patients treated with canal-sparing TSA humeral components have significantly lower rates of early calcar resorption with less severe bone loss when compared to patients treated using short and standard-length designs.

Artificial Intelligence and Machine Learning in Rotator Cuff Tears.

Rotator cuff tears (RCTs) negatively impacts patient well-being. Artificial intelligence (AI) is emerging as a promising tool in medical decision-making. Within AI, deep learning allows to autonomously solve complex tasks. This review assesses the current and potential applications of AI in the management of RCT, focusing on diagnostic utility, challenges, and future perspectives. AI demonstrates promise in RCT diagnosis, aiding clinicians in interpreting complex imaging data. Deep learning frameworks, particularly convoluted neural networks architectures, exhibit remarkable diagnostic accuracy in detecting RCTs on magnetic resonance imaging. Advanced segmentation algorithms improve anatomic visualization and surgical planning. AI-assisted radiograph interpretation proves effective in ruling out full-thickness tears. Machine learning models predict RCT diagnosis and postoperative outcomes, enhancing personalized patient care. Challenges include small data sets and classification complexities, especially for partial thickness tears. Current applications of AI in RCT management are promising yet experimental. The potential of AI to revolutionize personalized, efficient, and accurate care for RCT patients is evident. The integration of AI with clinical expertise holds potential to redefine treatment strategies and optimize patient outcomes. Further research, larger data sets, and collaborative efforts are essential to unlock the transformative impact of AI in orthopedic surgery and RCT management.

Robotic-Arm Assisted Lateral Unicompartmental Knee Arthroplasty: Case Series with Minimum Five-Year Follow-Up.

INTRODUCTION: Lateral unicompartmental knee arthroplasty has been shown to be a successful treatment modality for isolated lateral osteoarthritis (OA) of the knee. The reproduction of proper knee kinematics, limb alignment, as well as proper soft tissue balancing and component positioning have been shown to be of the utmost importance for a successful unicompartmental knee arthroplasty (UKA). Robotic assistance has shown to be a reliable tool in order to replicate these factors, as compared to manual instrumentation alone. Recent studies have shown the potential of robotic-assisted surgery in controlling these surgical factors for medial UKA; however, studies assessing outcomes of robotic-assisted lateral UKA (RAUKA) are lacking. Therefore, a retrospective single-center study was performed to assess outcomes of lateral RAUKA. MATERIALS AND METHODS: Patients who underwent lateral RAUKA from a single surgeon at a central institution between January 2008 and June 2017 were identified. All patients received a lateral UKA with a fixed-bearing metal backed onlay tibial component. Patients over the age of 18, with at least a five-year follow-up and a lateral UKA were contacted by phone and asked a series of questions to determine satisfaction and survivorship. Each patient was asked in a "yes" or "no" manner, if they have had their implant revised or reoperated for any reason, and a 5-point Likert scale was used to assess satisfaction. RESULTS: Data was collected from 50 patients (53 knees). Of the patients that responded: 32 (60%) were right knees; 32 (60%) were female, and average follow-up was 7.6 years (5-14 years). Of the 53 knees, one had a revision (98% survivorship). Excluding the revision, 51 (98%) of the included cases were either "very satisfied" or "satisfied" with their surgery. DISCUSSION/CONCLUSIONS: Robotic-arm assisted lateral UKA was found to have high survivorship and a satisfaction rate in patients that had at least a five-year follow-up. In the future, larger prospective comparison studies with longer follow-ups are necessary to adequately compare survivorship and satisfaction rates of robotic-assisted lateral UKA to conventional UKA.

Morbidly Obese Patients Undergoing Unicompartmental Knee Arthroplasty Compared to Total Knee Arthroplasty: A Retrospective Case-Controlled Analysis.

BACKGROUND: In this study, we assess the effects that morbid obesity (body mass index (BMI) ≥ 40) has on: (1) Ninety-day medical complications and readmission rates; (2) costs of care and lengths of stay (LOS); and (3) 2-year implant complications in patients undergoing unicompartmental knee arthroplasty (UKA) versus total knee arthroplasty (TKA). METHODS: A retrospective query of TKA and UKA patients were identified using a national database. Morbidly obese UKA patients were matched 1:5 to morbidly obese TKA patients by demographic and comorbidity profiles. Subgroup analyses were conducted using the same process between morbidly obese UKA patients and BMI <40 TKA patients, as well as to BMI <40 UKA patients. RESULTS: Morbidly obese patients who underwent UKA had significantly fewer medical complications, readmissions, and periprosthetic joint infections than TKA patients; however, UKA patients had greater odds of mechanical loosening (ML). The TKA patients had significantly longer LOS (3.0 versus 2.4 days, P < .001), as well as significantly greater costs of care than UKA patients ($12,869 versus $7,105). Morbidly obese UKA patients had similar rates of medical complications, and significantly lower readmissions, decreased LOS, and decreased costs when compared to TKA patients who had a BMI <40. CONCLUSION: In patients who have morbid obesity, complications were decreased in UKA compared to TKA. Moreover, morbidly obese UKA patients had lower medical utilizations and similar complication rates when compared to TKA patients with the recommended cutoff of BMI <40. However, UKA patients had greater rates of ML than TKA patients. A UKA may be an acceptable treatment option for unicompartmental osteoarthritis in morbidly obese patients.

Medial Varus Proximal Tibial Resection is Superior to Pie-Crusting of the Medial Collateral Ligament During Primary Total Knee Arthroplasty.

BACKGROUND: Medial varus proximal tibial (MPT) resection or soft tissue releases (STRs) of the medial collateral ligament (MCL) in the form of pie-crusting can be performed to achieve a balanced knee in a varus deformity. Studies comparing the 2 modalities have not been addressed within the literature. Therefore, the aims of this study were to assess the following: (1) compartmental changes between the 2 methods and (2) changes in patient-reported outcome measurements. METHODS: Using our institution's total joint arthroplasty registry, patients who underwent primary total knee arthroplasty from January 1, 2017, to December 31, 2019, were identified. The MPT resection and STR patients were 1:1 matched with baseline parameters yielding 196 patients. Outcomes of interest included: changes in compartmental pressures at 10, 45, and 90° degrees and change to the Short-Form 12, Western Ontario and McMaster Universities Osteoarthritis Index, and Forgotten Joint Scores (FJSs) at the 2-year follow-up period. A P value less than .05 was used as our threshold for statistical difference. RESULTS: The MPT resection led to significant reductions in compartmental pressures at 10° [43 versus 19 pounds (lbs.), P < .0001], 45° (43 versus 27 lbs., P < .0001), and 90° degrees (27 versus 16 lbs., P < .0001) compared to STR. MPT resection also had significantly improved Short-Form 12 (47 versus 38, P < .0001), Western Ontario and McMaster Universities Osteoarthritis Index (9 versus 21, P < .0001), and Forgotten Joint Score (79 versus 68, P = .005). CONCLUSION: Bone modification was superior to pie-crusting of the MCL in achieving consistent pressure balancing and improved outcomes. The investigation can guide surgeons on the preferred method to achieve a well-balanced knee.

Mid-Term Survivorship, Radiographic and Functional Outcomes of Robotic-Assisted Unicompartmental Knee Arthroplasty.

INTRODUCTION: The use of robotic-arm assistance for medial unicompartmental knee arthroplasty (RAUKA) has become an area of interest to overcome technical challenges, improve accuracy, and optimize patient outcomes. Due to the rise in osteoarthritis (OA) and robotic assistance, well-powered long-term studies are warranted. The aim of this study was to analyze midterm survivorship, radiographic changes, range of motion (ROM), and patient-reported outcome measurements (PROMs) of RAUKA. MATERIALS AND METHODS: Patients who underwent RAUKA for medial compartmental OA were identified from April 2009 to May 2014. The query yielded 162 knees with a mean follow up of 6.5 years. Primary endpoints were to compare survivorship, final mechanical axis alignment, radiographic changes, mean ROM, and changes to the following PROMs: Knee Society Score (KSS), International Knee Documentation Committee (IKDC), and Oxford Knee Score (OKS). Statistical analyses were primarily descriptive. A p-value less than 0.05 was considered statistically significant. RESULTS: There were no revisions of the primary implant, one case required exchange of polyethylene bearing and debridement for deep infection, and five cases required additional surgical intervention with implant retention. Overall survivorship was 100%. Radiographic assessment demonstrated no mechanical loosening or osteolysis surrounding the implant. Mean ROM was 3 to 121.9º. Patients demonstrated a mean functional KSS of 78.55, IKDC of 78.22, and OKS of 43.94. CONCLUSIONS: The study supports excellent mid-term outcomes in patients undergoing RAUKA for medial compartment OA. Longer term follow-up studies are necessary to determine the efficacy of this technology for patients undergoing RAUKA for medial compartment OA.

Risk of Periprosthetic Joint Infection After Intra-Articular Corticosteroid Injection Following Unicompartmental Knee Arthroplasty.

BACKGROUND: Perioperative intra-articular joint injection is a known risk factor for developing prosthetic joint infection (PJI) in the immediate preoperative and postoperative periods for total knee arthroplasty, but is less defined in unicompartmental knee arthroplasty (UKA). The goal of this study was to elucidate the risk of developing PJI after intra-articular corticosteroid injection (IACI) into a post UKA knee. METHODS: A retrospective review of a nationwide administrative claims database was performed from January 2015 to October 2020. Patients who underwent UKA and had an ipsilateral IACI were identified and matched 2:1 to a control group of primary UKA patients who did not receive IACI. Multivariate logistic analyses were conducted to assess differences in PJI rates at 6 months, 1 year, and 2 years. RESULTS: A total of 47,903 cases were identified, of which 2,656 (5.5%) cases received IACI. The mean time from UKA to IACI was 355 days. The incidence of PJI in the IACI group was 2.7%, compared to 1.3% in the control group. The rate of PJI after IACI was significantly higher than the rate in the control group at 6 months, 1 year, and 2 years (all P < .05). The majority of PJI occurred within the first 6 months following IACI (75%). CONCLUSION: In this study, IACI in a UKA doubled the risk of PJI compared to patients who did not receive an injection. Surgeons should be aware of this increased risk to aid in their decision-making about injecting into a UKA. LEVEL OF EVIDENCE: III, retrospective comparative study.

Femoral Nerve Compression due to Adverse Local Tissue Reaction After Ceramic-on-ceramic Total Hip Arthroplasty.

The use of metal bearings in total hip arthroplasty (THA) has been linked with adverse local tissue reactions (ALTRs). There is 1 reported case of ALTR from a ceramic-on-ceramic (CoC) bearing and none that resulted in nerve compression. In this case, a 71-year-old man presented with an ALTR after a CoC THA that resulted in femoral nerve compression. An anterior approach was utilized to revise his THA, which resulted in nerve decompression and near-resolution of his preoperative symptoms. We conclude that CoC bearings may not be completely inert and can result in ALTRs and nerve compression.

Comparison of reverse shoulder arthroplasty and total shoulder arthroplasty for patients with inflammatory arthritis.

BACKGROUND: End-stage glenohumeral joint arthritis is common in patients with inflammatory arthritis. Reverse shoulder arthroplasty (RSA) and anatomic total shoulder arthroplasty (TSA) are both indicated in this setting. RSA is often considered based on the impacts of long-standing inflammatory arthritis including glenoid and humeral bone erosion and rotator cuff insufficiency. However, acromial and scapular spine fractures following RSA have been reported more commonly in these patients, which can have a significant impact on outcomes. Currently, no study has directly compared the efficacy and complication rates of RSA vs. TSA in patients with inflammatory arthritis. This study aimed to investigate differences in clinical outcomes and complications in patients undergoing RSA vs. TSA with glenohumeral inflammatory arthritis. METHODS: We performed a retrospective review of 86 patients with inflammatory arthritis treated with primary RSA (n = 43) or TSA (n = 43) with a minimum of 2 years' follow-up. American Shoulder and Elbow Surgeons scores, Simple Shoulder Test scores, visual analog scale scores for pain and function, active range of motion, and patient self-ratings of upper-extremity normality (Subjective Assessment of Normal Evaluation [SANE]) were collected preoperatively and at minimum 2-year follow-up. Radiographic classification of preoperative glenoid and humeral bone loss was performed, and postoperative complications were observed. Revision and complication details were compared. RESULTS: The study cohort had an average age of 72.1 years (range, 31-92 years) and average follow-up period of 51.6 months (range, 22-159 months). Both the RSA and TSA cohorts demonstrated improvements in patient-reported outcome measures and ranges of motion; however, patients treated with TSA showed a greater postoperative final Simple Shoulder Test score (P < .001), visual analog scale score for function (P = .0347), active elevation (P = .0331), active external rotation (P < .001), active internal rotation (P = .005), and Single Assessment Numeric Evaluation (SANE) score (P = .0161). Analysis of complication rates demonstrated no statistically significant difference between cohorts. Four acromial fractures occurred in the RSA group. When RSA patients who sustained acromial fractures were removed from the analysis, there were minimal differences in outcomes between the RSA and TSA cohorts. CONCLUSION: TSA in patients with inflammatory arthritis leads to improved clinical outcomes but higher early revision rates when compared with RSA. RSA outcomes are negatively impacted by a high rate of postoperative acromial fractures.

Allogenic Perinatal Tissue for Musculoskeletal Regenerative Medicine Applications: A Systematic Review.

Producing tremendous amounts of stress and financial burden on the global patient population and healthcare systems around the world, most current modalities of treatment for musculoskeletal ailments often do not address the etiopathogenetic causes of these disorders. Regenerative medicine for musculoskeletal disorders relies on orthobiologics derived from either allogenic or autologous sources. Multiple drawbacks are associated with autologous sources, including donor-site morbidity, a dearth of studies, and variability in both patient reported and clinical/functional outcomes. On the other hand, allogenic sources address several of these concerns, and continue to be a suitable source of mesenchymal stem cells (MSCs). This review qualitatively reports both the preclinical and clinical outcomes of publications studying the applications of umbilical cord (-derived Wharton's jelly), amniotic suspension allograft, amniotic membrane, and amniotic fluid in musculoskeletal medicine. A systematic review was conducted utilizing the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines on studies published between January 2010 and October 2022 that used allogeneic perinatal tissues. Further randomized controlled clinical studies are necessary to properly evaluate the safety and efficacy of these tissues in orthopedic surgery.

Job-Related Performance and Quality of Life Benefits in First Responders Given Access to H-Wave® Device Stimulation: A Retrospective Cohort Study.

Current chronic pain treatments primarily target symptoms and are often associated with harmful side-effects and complications, while safer non-invasive electrotherapies like H-Wave® device stimulation (HWDS) have been less explored. The goal of this study is to evaluate first responder-reported effects of HWDS on job-related and quality-of-life measures. This is a retrospective cohort study where first responders were surveyed following voluntary use of HWDS regarding participant experience, frequency of use, job-related performance, and quality-of-life. Responses were analyzed using means comparison tests, while bivariate analysis assessed responses associated with HWDS usage. Overall, 92.9% of first responder HWDS users (26/28) reported a positive experience (p < 0.0001), with 82.1% citing pain reduction (p = 0.0013), while 78.6% indicated it would be beneficial to have future device access (p = 0.0046). Participants using H-Wave® were at least six times more likely to report higher rates of benefit (100% vs. 0%, p = 0.022), including pain reduction (91.3% vs. 8.7%, p = 0.021) and improved range-of-motion (93.3% vs. 69.2%, p = 0.044). Spending more time with family was associated with better job performance following frequent HWDS use (50% vs. 8.3%, p = 0.032). Repetitive first responder H-Wave® use, with minimal side effects and easy utilization, resulted in significant pain reduction, improvements in job performance and range-of-motion, and increased time spent with family, resulting in overall positive experiences and health benefits. Level of Evidence: III.

Alcohol Abuse, Morbid Obesity, Depression, Congestive Heart Failure, and Chronic Pulmonary Disease are Risk Factors for 90-Day Readmission After Arthroscopic Rotator Cuff Repair.

Purpose: The purpose of this study was to report the rate and causes of 90-day readmissions after arthroscopic rotator cuff repair. Methods: A retrospective query from January 2005 to March 2014 was performed using a nationwide administrative claims registry. Patients and complications were identified using International Classification of Disease, Ninth Revision (ICD-9) and Current Procedural Terminology (CPT) codes. Patients who underwent arthroscopic rotator cuff repair (RCR) and were readmitted within 90 days after their index procedure were identified. Patients not readmitted represented controls. Patients readmitted were stratified into separate cohorts depending on the primary cause of readmission, which included cardiac, endocrine, hematological, infectious, gastrointestinal, musculoskeletal (MSK), neoplastic, neurological or psychiatric, pulmonary, and renal. Risk factors assessed were comorbidities comprising the Elixhauser-Comorbidity Index (ECI). Primary outcomes analyzed and compared included cause for readmission, patient demographics, risk factors, in-hospital length of stay (LOS), and costs. Pearson's chi-square was used to compare patient demographics, and multivariate binomial logistic regression was used to calculate odds ratios (OR) on patient-related risk factors for 90-day readmissions. Results: 10,425 readmitted patients and 301,625 control patients were identified, representing a 90-day readmission rate of 3.5%. The causes of readmissions were primarily related to infectious diseases (15%), MSK (15%), and cardiac (14%) complications. The most common MSK readmissions were osteoarthrosis of the leg or shoulder (24.8%) and spinal spondylosis (8.4%). Multivariate binomial logistic regression analyses demonstrated patients with alcohol abuse (OR, 1.42; P < .0001), morbid obesity (OR, 1.38; P < .0001), depression (OR, 1.35; P < .0001), congestive heart failure (OR, 1.34; P < 0.0001), and chronic pulmonary disease (OR, 1.28; P < .0001) were at the greatest risk of readmissions after RCR. Conclusions: Significant differences exist among patients readmitted, and those patients who do not require hospital readmission within 90 days following arthroscopic rotator cuff repairs. Readmissions are associated with significant patient comorbidities and were primarily related to medically based complications. Level of Evidence: Level III, prognostic, retrospective cohort study.

Long noncoding RNAs in mesenchymal stromal/stem cells osteogenic differentiation: Implications in osteoarthritis pathogenesis.

This letter focuses on a recently published article that provided an exceptional description of the effect of epigenetic modifications on gene expression patterns related to skeletal system remodeling. Specifically, it discusses a novel modality of epigenetic regulation, the long noncoding RNAs (lncRNAs), and provides evidence of their involvement in mesenchymal stromal/stem cells osteo-/adipo-genic differentiation balance. Despite focus on lncRNAs, there is an emerging cross talk between lncRNAs and miRNAs interaction as a novel mechanism in the regulation of the function of the musculoskeletal system, by controlling bone homeostasis and bone regeneration, as well as the osteogenic differentiation of stem cells. Thus, we touched on some examples to demonstrate this interaction. In addition, we believe there is still much to discover from the effects of lncRNAs on progenitor and non-progenitor cell differentiation. We incorporated data from other published articles to review lncRNAs in normal progenitor cell osteogenic differentiation, determined lncRNAs involved in osteoarthritis pathogenesis in progenitor cells, and provided a review of lncRNAs in non-progenitor cells that are differentially regulated in osteoarthritis. In conclusion, we really enjoyed reading this article and with this information we hope to further our under standing of lncRNAs and mesenchymal stromal/stem cells regulation.

Allogenic perinatal tissue for musculoskeletal regenerative medicine applications: a systematic review protocol.

BACKGROUND: Musculoskeletal ailments impact the lives of millions of people, and at times necessitate surgery followed by physiotherapy, drug treatments, or immobilization. Regenerative musculoskeletal medicine has undergone enormous progress over the last few decades. Sources of tissues used for regenerative medicine purposes can be grouped into autologous or allogenic. Although autologous sources are promising, there is a wide range of limitations with the treatment, including the lack of randomized controlled studies for orthopaedic conditions, donor site morbidity, and highly variable outcomes for patients. Allogenic sources bypass some of these shortcomings and are a promising source for orthopaedic regenerative medicine applications. METHODS: A systematic search will be performed using PubMed, Elsevier, ScienceDirect, and Google Scholar databases for articles published in English before May 2022. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement and guidelines will be used. Studies will be eligible if they apply to acute and chronic orthopaedic musculoskeletal complications or animal or human disease models. Publications must include the use of MSCs and/or tissue obtained from amniotic/chorionic membrane, amniotic fluid, umbilical cord, and/or umbilical cord-derived Wharton's jelly as an intervention. Placebos, noninjury models, acute injury models, non-injury models, and gold standard treatments will be compared. The study selection will be performed by two independent reviewers using a dedicated reference management software. Data synthesis and meta-analysis will be performed separately for preclinical and clinical studies. DISCUSSION: The results will be published in relevant peer-reviewed scientific journals. Investigators will present results at national or international conferences. TRIAL REGISTRATION: The Protocol will be registered on PROSPERO international prospective register of systematic reviews prior to commencement.

Functional internal rotation is similar between lesser tuberosity osteotomy and subscapularis peel in total shoulder arthroplasty: short-term follow-up.

INTRODUCTION: Lesser tuberosity osteotomy (LTO) and subscapularis peel (Peel) are 2 common techniques used to mobilize the subscapularis tendon during anatomic total shoulder arthroplasty (TSA). The literature is inconclusive over which technique is optimal; thus, controversy exists over which technique should be performed. The purpose of this study was to compare specific functional internal rotation tasks and general outcome scores in TSA patients who received either an LTO or Peel. METHODS: A retrospective review of 563 patients treated with primary TSA using either an LTO (n = 358) or Peel (n = 205) with a minimum 2-year follow-up was performed. Subjective internal rotation, active internal rotation, and specific questions related to functional internal rotation isolated from the Simple Shoulder Test (SST) and American Shoulder and Elbow Surgeons functional questionnaires were reviewed. Other outcome scores including visual analog scale pain and function, Single Assessment Numerical Evaluation, SST, American Shoulder and Elbow Surgeons, and revision rates were compared between the 2 groups. RESULTS: The study found no difference in postoperative functional internal rotation and range of motion between LTO and Peel. Patients who received a Peel were shown to have a slightly greater improvement in the ability to perform toileting and a higher average change in SST score that did not reach clinical significance. There was no difference in the percentage of maximal improvement, revision rate, or need for revision between the 2 groups. CONCLUSION: No difference was found between the LTO and Peel techniques in regard to functional tasks of internal rotation at short-term follow-up.

Coracoid Impingement and Morphology Is Associated with Fatty Infiltration and Rotator Cuff Tears.

This study describes measurements between the coracoid, glenoid, and humerus; characterizes coracoid shape, rotator cuff fatty infiltration, and quantitatively evaluates coracoid impingement and its association with anterosuperior rotator cuff tears (ASCT). 193 shoulder magnetic resonance imaging (MRI) scans demonstrating: rotator cuff tear; isolated tear of the supraspinatus; tear of supraspinatus and subscapularis, were included. MRI measurements included coracohumeral interval (CHI), coracoid overlap (CO), coracoid recess (CR), coracoglenoid angle (CGA), and coracoglenoid interval (CGI) on axial slices; acromiohumeral interval (AHI) on coronal slices; and coracohumeral interval (CHI) and coracoacromial ligament (CAL) thickness on sagittal slices. The coracoid shape was classified as flat, curved, or hooked. An Independent T-test was used to compare the MRI measurements and the different rotator cuff tear groups. In 79% of the patients with ASCT tears, the coracoid was curved. Axial CHI, CGA, sagittal CHI, and AHI were decreased in ASCT when compared to no tears and isolated supraspinatus tears (p < 0.05). CO was increased in ASCT compared to no tears and isolated supraspinatus tears (p < 0.05). Patients with an ASCT had a significantly increased subscapularis and supraspinatus Goutallier fatty infiltration score when compared to no tear and isolated supraspinatus tears (p < 0.05). These quantitative measurements may be useful in identifying patients at risk for ASCT. Level of Evidence III.

A comparison of patient same-day discharge selection after shoulder arthroplasty before and after the COVID-19 pandemic.

Background: Early discharge has been a target of cost control efforts, given the growing demand for joint replacement surgery. Select patients are given the choice for same-day discharge (SDD) or overnight stay after shoulder arthroplasty. The COVID-19 pandemic changed patient perspectives regarding hospital visitation and admission. The purpose of this study was to determine if the COVID-19 pandemic impacted the utilization of SDD after shoulder arthroplasty. We hypothesize that patients undergoing shoulder arthroplasty after the start of the COVID-19 pandemic will have higher rates of SDD. Methods: A retrospective continuous review was performed on 370 patients who underwent a primary anatomic (total shoulder arthroplasty) or reverse shoulder arthroplasty between August 2019 and December 2020 by a single surgeon. This group of patients represent the 185 arthroplasty cases completed before the COVID-19 pandemic and the first 185 patients after the start of the pandemic. April 1, 2020, was chosen as the cutoff for pre-COVID patients, as this represents the date a statewide ban on elective surgery was declared. All patients were counseled preoperatively regarding SDD and given the choice to stay overnight, unless medically contraindicated. Demographics, medical history, length of stay, 30- and 90-day readmissions, and 90-day emergency room (ER) and urgent care visits were obtained from medical records and compared. Two-tailed student t-tests, chi-square tests, and Fischer's exact were performed where appropriate. Results: The 2 groups were similar in age, body mass index, gender distribution, and Outpatient Arthroplasty Risk Assessment score. During the collection period, there were more anatomic shoulder arthroplasties performed after (54%) than before (44%) the COVID-19 pandemic (P = .029). Patients treated after the start of the COVID-19 pandemic were almost 3 times more likely to have an SDD (P < .001), with 85.4% (158/185) of patients being discharged the same day after COVID-19, compared with 34.6% (64/185) before COVID-19. Discharge disposition (location of discharge) was significantly different, as 99% (183/185) of patients undergoing surgery after the start of the COVID-19 pandemic were discharged home, compared with 94% (174/185) of patients before COVID-19. There was no difference in 30-day readmissions, 90-day readmissions, and 90-day (ER) and urgent care visits between the 2 groups. Conclusion: Our study suggests that the COVID-19 pandemic has dramatically impacted patient choices for SDD within a single surgeon's practice, with nearly 3 times as many patients electing for SDD. Readmissions and ER visits were similar, indicating that SDD remains a safe alternative for patients after total shoulder arthroplasty and reverse shoulder arthroplasty. Level of evidence: Level III; Retrospective Comparative Study.