Spin in the Abstracts of Meta-analyses and Systematic Reviews: Quadriceps Tendon Graft for Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Spin is a reporting bias that misrepresents research. Ultimately it can affect surgeon decision making and patient care. Anterior cruciate ligament (ACL) reconstruction is common, but debate continues over optimal treatment modalities. PURPOSE: To identify the prevalence of spin in meta-analysis and systematic review abstracts regarding the treatment of ACL injuries with quadriceps tendon graft. STUDY DESIGN: Cross-sectional study. METHODS: Electronic libraries (MEDLINE, Embase, Web of Science, Google Scholar) were searched for meta-analyses and systematic reviews regarding the treatment of ACL tears with quadriceps tendon graft. The 9 most severe types of spin commonly found in abstracts were used as an evaluation tool to assess the articles. Two reviewers each performed a blinded assessment of each article for spin. A third reviewer helped after review was done to address any discrepancies between the original reviewers. Further evaluation included year of publication, number of citations, journal impact factor, and A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR-2) score. RESULTS: The electronic database search resulted in 986 articles, of which 13 met our inclusion criteria. After review, we found that 53.8% (7/13) of the included articles contained 1 of the 9 most severe forms of spin. Of the 13 articles, 15.4% (n = 2) contained 2 types of spin, and 38.5% (n = 5) contained 1 type of spin. No studies contained ≥3 types of spin. Of the types of spin evaluated, the most prevalent (n = 4; 30.8%) was type 3 ("selective reporting of or overemphasis on efficacy outcomes or analysis favoring the beneficial effect of the experimental intervention"). All studies, regardless of the presence of spin, were found to be low or critically low quality according to the AMSTAR-2 assessment. CONCLUSION: This study demonstrated the presence of spin in 53.8% of meta-analysis and systematic review abstracts pertaining to quadriceps tendon graft for ACL reconstruction. Orthopaedic surgeons should learn to recognize spin as they review articles when deciding the treatment course for ACL injuries. Additionally, strict criteria should be considered to reduce the prevalence of spin in orthopaedic literature.

Medial-Sided Ligamentous Injuries of the Athlete's Knee: Evaluation and Management.

The superficial medial collateral ligament (sMCL) is the most commonly injured ligamentous structure in the knee. The other medial knee stabilizers include the deep medial collateral ligament, the posterior oblique ligament, and the medial meniscus. Medial collateral ligament injuries frequently occur in young athletes. As a result of the good healing capacity of the sMCL, the majority of acute medial-sided knee injuries can be treated nonoperatively with good outcomes. However, missed concomitant injuries can lead to residual laxity and instability of the knee when treated conservatively. When surgical management is warranted, numerous techniques exist, including repair, augmentation, and reconstruction. Recent anatomic and biomechanical studies defining the attachment sites and functional roles of the individual medial knee structures have led to advancements in diagnosis, treatment, and rehabilitation. These studies have allowed for the development of an anatomic reconstruction technique that restores the native stability and load-sharing relationships among the medial knee structures. The purpose of this narrative review is to summarize the recent updates in the anatomy, biomechanics, evaluation, and treatment of ligamentous injuries on the medial side of the athlete's knee.

Biomechanical Comparison of Adjustable-Loop Femoral Cortical Suspension Devices for Soft Tissue ACL Reconstruction.

Background: Several new adjustable-loop devices (ALDs) for anterior cruciate ligament reconstruction (ACLR) have not been tested in vitro. Purpose: To compare the biomechanical performances of 5 ALDs under a high cyclic load and forces representative of the return-to-play conditions seen in the recovering athlete. Study Design: Controlled laboratory study. Methods: A total of 10 devices for each of 5 chosen ALDs (UltraButton [Smith & Nephew], RigidLoop [DePuy Mitek], ProCinch [Stryker], TightRope [Arthrex], and ToggleLoc [Biomet]) were tested in a device-only model. The devices were secured to a servohydraulic test machine and preconditioned from 10 to 75 N at a rate of 0.5 Hz for 20 cycles. They were then subjected to high cyclic forces (100-500 N for 4000 cycles) and subsequently pulled to failure at 50 mm/min. The preconditioning displacement, permanent deformation, cumulative peak displacement, stiffness coefficient, and load to failure data were collected. Results: The UltraButton displayed the greatest preconditioning displacement (0.22 ± 0.20 mm), followed by the RigidLoop (0.11 ± 0.03 mm), ProCinch (0.07 ± 0.04 mm), TightRope (0.07 ± 0.02 mm), and ToggleLoc (0.02 ± 0.03 mm). The TightRope displayed the greatest permanent deformation (3.19 ± 1.03 mm) followed by the UltraButton (2.14 ± 0.92 mm), ToggleLoc (2.02 ± 1.09 mm), RigidLoop (1.67 ± 0.1 mm), and ProCinch (1.38 ± 0.18 mm). The TightRope displayed the greatest cumulative peak displacement (3.69 ± 1.03 mm) followed by the UltraButton (2.46 ± 0.92 mm), ToggleLoc (2.37 ± 1.08 mm), RigidLoop (2.01 ± 0.1 mm), and ProCinch (1.75 ± 0.19 mm). The UltraButton displayed the largest stiffness coefficient (1347.22 ± 136.33 N/mm) followed by the RigidLoop (1325.4 ± 116.37 N/mm), ToggleLoc (1216.62 ± 131.32 N/mm), ProCinch (1155.56 ± 88.04), and TightRope (848.48 ± 31.94). The ToggleLoc displayed the largest load to failure (1874.42 ± 101.08 N) followed by the RigidLoop (1614.12 ± 129.11 N), UltraButton (1391.69 ± 142.04 N), ProCinch (1384.85 ± 58.62 N), and TightRope (991.8 ± 51.1 N.). Conclusion: The 5 ALDs exhibited different biomechanical properties. None of them had peak cumulative displacements for which the confidence interval lay above 3 mm, thus no single device was determined to have a higher rate of clinical failure compared with the others. Clinical Relevance: ALD choice may affect biomechanics after ACLR.

Radiofrequency in arthroscopic shoulder surgery: a systematic review.

BACKGROUND: Radiofrequency has seen an increase in use in orthopedics including cartilage lesion debridement in the hip and knee as well as many applications in arthroscopic shoulder surgery. The purpose of this systematic review is to evaluate the safety and usage of radiofrequency in the shoulder. METHODS: This systematic review was registered with PROSPERO (international registry) and followed the preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) guidelines. Embase and PubMed were searched using: "shoulder," "rotator cuff," "biceps," "acromion" AND "monopolar," "bipolar," "ablation," "coblation," and "radiofrequency ablation." The title and abstract review were performed independently. Any discrepancies were addressed through open discussion. RESULTS: A total of 63 studies were included. Radiofrequency is currently utilized in impingement syndrome, fracture fixation, instability, nerve injury, adhesive capsulitis, postoperative stiffness, and rotator cuff disease. Adverse events, namely superficial burns, are limited to case reports and case series, with higher-level evidence demonstrating safe use when used below the temperature threshold. Bipolar radiofrequency may decrease operative time and decrease the cost per case. CONCLUSIONS: Shoulder radiofrequency has a wide scope of application in various shoulder pathologies. Shoulder radiofrequency is safe; however, requires practitioners to be cognizant of the potential for thermal burn injuries. Bipolar radiofrequency may represent a more efficacious and economic treatment modality. Safety precautions have been executed by institutions to cut down patient complications from shoulder radiofrequency. Future research is required to determine what measures can be taken to further minimize the risk of thermal burns.

Fragility of statistically significant findings from randomized clinical trials of surgical treatment of humeral shaft fractures: A systematic review.

BACKGROUND: Despite recent meta-analyses of randomized controlled trials (RCTs), there remains no consensus regarding the preferred surgical treatment for humeral shaft fractures. The fragility index (FI) is an emerging tool used to evaluate the robustness of RCTs by quantifying the number of participants in a study group that would need to switch outcomes in order to reverse the study conclusions. AIM: To investigate the fragility index of randomized control trials assessing outcomes of operative fixation in proximal humerus fractures. METHODS: We completed a systematic review of RCTs evaluating the surgical treatment of humeral shaft fractures. Inclusion criteria included: articles published in English; patients randomized and allotted in 1:1 ratio to 2 parallel arms; and dichotomous outcome variables. The FI was calculated for total complications, each complication individually, and secondary surgeries using the Fisher exact test, as previously published. RESULTS: Fifteen RCTs were included in the analysis comparing open reduction plate osteosynthesis with dynamic compression plate or locking compression plate, intramedullary nail, and minimally invasive plate osteosynthesis. The median FI was 0 for all parameters analyzed. Regarding individual outcomes, the FI was 0 for 81/91 (89%) of outcomes. The FI exceeded the number lost to follow up in only 2/91 (2%) outcomes. CONCLUSION: The FI shows that data from RCTs regarding operative treatment of humeral shaft fractures are fragile and does not demonstrate superiority of any particular surgical technique.

Liposomal Bupivacaine Associated with Cost Savings during Postoperative Pain Management in Fragility Intertrochanteric Hip Fractures.

Background: Intertrochanteric hip fractures are among the most common and most expensive diagnoses in the Medicare population. Liposomal bupivacaine is a novel preparation of a commonly used analgesic agent that, when used intraoperatively, decreases narcotic requirements and hospital length of stay and increases the likelihood of discharge to home. The purpose of this investigation was to determine whether there was an economic benefit to utilizing intraoperative liposomal bupivacaine in patients with fragility intertrochanteric hip fractures in comparison to a group of patients who did not receive liposomal bupivacaine. Methods: This is a retrospective observational study performed at two academic medical centers. Fifty-six patients with intertrochanteric hip fractures treated with cephalomedullary nail implant who received standard hip fracture pain management protocol were compared to a cohort of 46 patients with intertrochanteric hip fractures who received additional intraoperative injections of liposomal bupivacaine. All other standards of care were identical. A cost analysis was completed including the cost of liposomal bupivacaine, operating room costs, and discharge destination. Statistical significance was set at p < 0.05. Results: Although the length of hospital stay was similar between the two groups (3.2 days vs. 3.8 days, p = 0.08), patients receiving intraoperative liposomal bupivacaine had a lower likelihood of discharge to a skilled nursing facility (84.8% vs. 96.4%, p = 0.002) and a longer operative time (73.4 minutes vs 67.2 minutes, p = 0.004). The cost-benefit analysis indicated that for an investment of $334.18 in the administration of 266 mg of liposomal bupivacaine, there was a relative saving of $1,323.21 compared to the control group. The benefit-cost ratio was 3.95, indicating a $3.95 benefit for each $1 spent in liposomal bupivacaine. Conclusions: Despite the increased initial cost, intraoperative use of liposomal bupivacaine was found to be a cost-effective intervention due to the higher likelihood of discharge to home during the postoperative management of patients with intertrochanteric hip fractures.

Cement augmentation of suture anchors in the proximal humerus during rotator cuff repair improves pullout strength: a systematic review.

IMPORTANCE: Rotator cuff pathology is a growing concern in the ageing population. If cement augmentation of suture anchors improves pullout strength, its application can potentially be applied in cases of poor bone quality to prevent anchor failure. OBJECTIVE: To evaluate the biomechanical benefits and fixation strength of cement-augmented versus non-augmented suture anchors in the proximal humerus during rotator cuff repair (RCR). EVIDENCE REVIEW: A systematic review of PubMed, Embase and Cochrane Library was performed to identify all published articles reporting on biomechanical analysis of suture anchors in the shoulder in a cadaveric model. Inclusion criteria required fresh-frozen specimens, placement in the footprint of the proximal humerus, and comparative assessment of fixation constructs with or without polymethylmethacrylate (PMMA) or bioabsorbable composite cement augmentation. Biomechanical testing procedure, cement augmentation method and pullout force were assessed. FINDINGS: After review of 105 abstracts, seven full manuscripts met inclusion criteria. Six of seven studies reported statistically significant differences in mean pullout force between augmented (three PMMAs, three composites, one PMMA vs composite) and non-augmented anchors. Of two studies evaluating cycles to failure, both found a significant increase in the augmented versus non-augmented anchors. Of two studies stratifying by anchor position, both investigations identified significant differences in mean pullout strength between augmented and non-augmented anchors at the posteromedial and anterolateral anchor positions. CONCLUSIONS AND RELEVANCE: Cement augmentation of suture anchors in cadaveric humeri for RCR improves pullout strength regardless of cement type used or anchor position. Cement augmentation may provide a viable option for future clinical application. LEVEL OF EVIDENCE: IV, systematic review.

Isolated Biceps Tenodesis and Tenotomy: A Systematic Review of Indications and Patient Satisfaction.

Biceps tenodesis and tenotomy are increasingly being used as treatment options for shoulder pathology, but patient satisfaction remains largely unstudied. A systematic review of the MEDLINE database was conducted to identify clinical outcome studies on isolated biceps tenodesis or tenotomy that reported patient satisfaction. Within the 15 investigations that were included, the indication for tenotomy was rotator cuff pathology, whereas the indication for tenodesis was biceps pathology or type 2 superior labral tear from anterior to posterior. Patients undergoing tenotomy were 13.6 years older than those undergoing tenodesis (P<.001). Patient satisfaction was high following both procedures, at 85.6% following tenotomy and 92.3% following tenodesis. [Orthopedics. 2021;44(6):333-340.].

Progranulin signaling in sepsis, community-acquired bacterial pneumonia and COVID-19: a comparative, observational study.

BACKGROUND: Progranulin is a widely expressed pleiotropic growth factor with a central regulatory effect during the early immune response in sepsis. Progranulin signaling has not been systematically studied and compared between sepsis, community-acquired pneumonia (CAP), COVID-19 pneumonia and a sterile systemic inflammatory response (SIRS). We delineated molecular networks of progranulin signaling by next-generation sequencing (NGS), determined progranulin plasma concentrations and quantified the diagnostic performance of progranulin to differentiate between the above-mentioned disorders using the established biomarkers procalcitonin (PCT), interleukin-6 (IL-6) and C-reactive protein (CRP) for comparison. METHODS: The diagnostic performance of progranulin was operationalized by calculating AUC and ROC statistics for progranulin and established biomarkers in 241 patients with sepsis, 182 patients with SIRS, 53 patients with CAP, 22 patients with COVID-19 pneumonia and 53 healthy volunteers. miRNAs and mRNAs in blood cells from sepsis patients (n = 7) were characterized by NGS and validated by RT-qPCR in an independent cohort (n = 39) to identify canonical gene networks associated with upregulated progranulin at sepsis onset. RESULTS: Plasma concentrations of progranulin (ELISA) in patients with sepsis were 57.5 (42.8-84.9, Q25-Q75) ng/ml and significantly higher than in CAP (38.0, 33.5-41.0 ng/ml, p < 0.001), SIRS (29.0, 25.0-35.0 ng/ml, p < 0.001) and the healthy state (28.7, 25.5-31.7 ng/ml, p < 0.001). Patients with COVID-19 had significantly higher progranulin concentrations than patients with CAP (67.6, 56.6-96.0 vs. 38.0, 33.5-41.0 ng/ml, p < 0.001). The diagnostic performance of progranulin for the differentiation between sepsis vs. SIRS (n = 423) was comparable to that of procalcitonin. AUC was 0.90 (95% CI = 0.87-0.93) for progranulin and 0.92 (CI = 0.88-0.96, p = 0.323) for procalcitonin. Progranulin showed high discriminative power to differentiate bacterial CAP from COVID-19 (sensitivity 0.91, specificity 0.94, AUC 0.91 (CI = 0.8-1.0) and performed significantly better than PCT, IL-6 and CRP. NGS and partial RT-qPCR confirmation revealed a transcriptomic network of immune cells with upregulated progranulin and sortilin transcripts as well as toll-like-receptor 4 and tumor-protein 53, regulated by miR-16 and others. CONCLUSIONS: Progranulin signaling is elevated during the early antimicrobial response in sepsis and differs significantly between sepsis, CAP, COVID-19 and SIRS. This suggests that progranulin may serve as a novel indicator for the differentiation between these disorders. TRIAL REGISTRATION: Clinicaltrials.gov registration number NCT03280576 Registered November 19, 2015.

Single-minded 2 is required for left-right asymmetric stomach morphogenesis.

The morphogenesis of left-right (LR) asymmetry is a crucial phase of organogenesis. In the digestive tract, the development of anatomical asymmetry is first evident in the leftward curvature of the stomach. To elucidate the molecular events that shape this archetypal laterality, we performed transcriptome analyses of the left versus right sides of the developing stomach in frog embryos. Besides the known LR gene pitx2, the only gene found to be expressed asymmetrically throughout all stages of curvature was single-minded 2 (sim2), a Down Syndrome-related transcription factor and homolog of a Drosophila gene (sim) required for LR asymmetric looping of the fly gut. We demonstrate that sim2 functions downstream of LR patterning cues to regulate key cellular properties and behaviors in the left stomach epithelium that drive asymmetric curvature. Our results reveal unexpected convergent cooption of single-minded genes during the evolution of LR asymmetric morphogenesis, and have implications for dose-dependent roles of laterality factors in non-laterality-related birth defects.

Use of Novel Radiofrequency Wand for the Application of the Biceps Tenotomy and Subacromonical Bursectomy.

Rotator cuff tears in patients can lead to a surgical intervention to relieve the pain and improve the function of the shoulder joint. In the majority of cases, the rotator cuff repair is completed arthroscopically and requires the ability for soft-tissue resection and visualization to restore the anatomic structures to their native state. With the advent of a radiofrequency wand, the technical aspects of a biceps tenotomy from the insertion point on the glenoid can be completed, along with the ability to resect, ablate, and coagulate tissue, using a single instrument. Although bone resection is completed with a bone cutting shaver and/or burr, the soft-tissue dissection can be completed in a precise and efficient manner.

Workers' Societal Costs After Knee and Shoulder Injuries and Diagnosis with In-Office Arthroscopy or Delayed MRI: A Cost-Minimization Analysis.

The goal of this study was to evaluate the societal costs of using in-office diagnostic arthroscopy (IDA) compared with magnetic resonance imaging (MRI) for the diagnosis of intra-articular knee and shoulder pathology in employed patients receiving Workers' Compensation or disability coverage. The prevalence is estimated at 260,000 total cases per year. METHODS: A cost-minimization analysis of IDA compared with MRI was conducted. Direct costs (in 2018 U.S. dollars) were calculated from private reimbursement amounts and Medicare. Indirect costs were estimated from a societal perspective including effects of delayed surgical procedures on the ability to work, lost income, Workers' Compensation or disability coverage, and absenteeism. Four regions were selected: Boston, Massachusetts; Detroit, Michigan; Denver, Colorado; and San Bernadino, California. Sensitivity analyses were performed using TreeAge Pro 2019 software. The base assumption was that it would take approximately 4 weeks for a diagnosis with MRI and 0 weeks for a diagnosis with IDA. RESULTS: Direct costs to determine a knee diagnosis with IDA were $556 less expensive (California) to $470 more expensive (Massachusetts) than MRI. Assuming a 4-week wait, societal costs (indirect and direct) for knee diagnosis were anywhere from $7,852 (Denver) to $11,227 (Boston) less using IDA. Direct costs were similar for shoulder pathology. In order for MRI to be the less costly option, the MRI and the follow-up visit to the physician would need to occur directly after consultation. Under Medicare, direct costs were similar for both the knee and shoulder when comparing IDA and MRI. Including indirect costs resulted in IDA being the less costly option. CONCLUSIONS: The use of IDA instead of MRI for the diagnosis of knee and shoulder pathology reduced costs. The potential savings to society were approximately $7,852 to $11,227 per operative patient and were dependent on scheduling and follow-up using MRI and on Workers' Compensation. LEVEL OF EVIDENCE: Economic and Decision Analysis Level IV. See Instructions for Authors for a complete description of levels of evidence.

Assessment and Trends of the Methodological Quality of the Top 50 Most Cited Articles on Patellar Instability.

BACKGROUND: Studies with a low level of evidence (LOE) have dominated the top cited research in many areas of orthopaedics. The wide range of treatment options for patellar instability necessitates an investigation to determine the types of studies that drive clinical practice. PURPOSE: To determine (1) the top 50 most cited articles on patellar instability and (2) the correlation between the number of citations and LOE or methodological quality. STUDY DESIGN: Cross-sectional study. METHODS: The Scopus and Web of Science databases were assessed to determine the top 50 most cited articles on patellar instability between 1985 and 2019. Bibliographic information, number of citations, and LOE were collected. Methodological quality was calculated using the Modified Coleman Methodology Score (MCMS) and the Methodological Index for Non-Randomized Studies (MINORS). Mean citations and mean citation density (citations per year) were correlated with LOE, MCMS, and MINORS scores. RESULTS: Most studies were cadaveric (n = 10; 20.0%), published in the American Journal of Sports Medicine (n = 13; 26.0%), published between 2000 and 2009 (n = 41; 82.0%), and conducted in the United States (n = 17; 34.0%). The mean number of citations and the citation density were 158.61 ± 59.53 (range, 95.5-400.5) and 12.74 ± 5.12, respectively. The mean MCMS and MINORS scores were 59.62 ± 12.58 and 16.24 ± 3.72, respectively. No correlation was seen between mean number of citations or citation density versus LOE. A significant difference was found in the mean LOE of articles published between 1990 and 1999 (5.0 ± 0) versus those published between 2000 and 2009 (3.12 ± 1.38; P = .03) and between 2010 and 2019 (3.00 ± 1.10; P = .01). CONCLUSION: There was a shift in research from anatomy toward outcomes in patellar instability; however, these articles demonstrated low LOE and methodological quality. Higher quality studies are necessary to establish informed standards of management of patellar instability.

Timeline for maximal subjective outcome improvement following total ankle arthroplasty.

BACKGROUND: Maximal medical improvement (MMI) establishes the timepoint when patients no longer experience clinically significant improvements following surgery. The purpose of this investigation is to establish when patients achieve MMI following total ankle arthroplasty (TAA) through the use of patient reported outcome measures (PROMs). METHODS: A systematic review to identify studies on TAA which reported consecutive PROMs for two years postoperatively was performed. Pooled analysis was done at 6 months, 12 months, and 24 months. Clinically significant improvement was defined as improvement between time intervals exceeding the minimal clinically important difference. RESULTS: Twelve studies and 1514 patients met inclusion criteria. Clinically significant improvement was seen up to 6 months postoperatively in both the American Orthopaedic Foot and Ankle Society Ankle Hindfoot Score and Visual Analog Scale scoring systems. The Short Musculoskeletal Function Assessment Dysfunction and Bother subsections showed maximal clinically significant improvement by 1 year postoperatively. CONCLUSION: Following TAA, MMI is seen by one year postoperatively. Physicians may allocate the majority of resources within the first year when most of the improvement is perceived. This data may help inform preoperative counseling as it establishes a timeline for MMI. LEVEL OF EVIDENCE: IV.

Efficacy of the modified Frailty Index and the modified Charlson Comorbidity Index in predicting complications in patients undergoing operative management of proximal humerus fracture.

BACKGROUND: Comorbidity indices such as the 5-factor modified Frailty Index (mFI-5) and modified Charlson Comorbidity Index (mCCI) are widely used in outcomes research. METHODS: A total of 3893 patients who underwent total shoulder arthroplasty (n=975), hemiarthroplasty (n=495), or open reduction and internal fixation (n=2423) for the treatment of proximal humerus fracture from 2005-2017 were identified from the National Surgical Quality Improvement Program database. Data regarding demographics, comorbidities, American Society of Anesthesiologists class, and postoperative complications were collected, and the mFI-5 and mCCI were calculated for each case. Multivariate logistic regression models and receiver operating characteristic curve analyses were performed. RESULTS: The patient population had a mean age of 68.0 ± 13.2 years, body mass index of 29.1 ± 8.1 and mean operative time of 119.9 ± 55.5 minutes. The most common complications within this cohort were extended length of stay (4 days or more) (1085/3893; 27.87%), transfusion (377/3893; 9.68%), unplanned reoperation (97/3893; 2.49%), urinary tract infection (43/3893; 1.10%), death (42/3893; 1.08%), and deep vein thrombosis (40/3893; 1.03%). After accounting for patient demographics, the mFI-5 (odds ratio [OR] = 1.105, P < .001) and mCCI (OR = 1.063, P < .001) were significantly associated with incidence of any adverse event. Both comorbidity indices had low positive predictive value and high negative predictive value for all adverse events. CONCLUSION: The comorbidity indices mCCI and mFI-5 are both strongly associated with adverse events but have moderate ability to predict complications following surgical treatment of proximal humerus fractures.

Rates and Risk Factors of Revision Arthroscopy or Conversion to Total Knee Arthroplasty Within 1 Year Following Isolated Meniscectomy.

PURPOSE: To identify the rates of and risk factors for revision arthroscopy and conversion to total knee arthroplasty (TKA) within 1 year of isolated meniscectomy. METHODS: Humana and Medicare national insurance databases were queried for patients who underwent isolated meniscectomy. Patients who underwent revision arthroscopy or TKA within 1 year postoperatively were identified by International Classification of Diseases Procedural Codes, Ninth Revision, and Current Procedural Terminology codes. Multivariate binomial logistic regression analysis was used to identify risk factors, and adjusted odds ratios (ORs) and 95% confidence intervals (Cis) were calculated, with P < .05 considered significant. RESULTS: A total of 13,142 patients and 407,888 patients underwent isolated meniscectomy in the Humana and Medicare databases, respectively. Of the patients, 395 (3.01%) and 3,770 patients (0.92%) underwent revision arthroscopy, and 629 patients (4.79%) and 38,630 patients (9.47%) underwent TKA within 1 year of meniscectomy in the Humana and Medicare databases, respectively. Obesity (Humana: OR = 1.33, P = 0.003; Medicare: OR = 1.10, P < 0.001) and age < 20 years (Humana: OR = 2.64, P = 0.022), 20-29 years (Humana: OR = 3.30, P = 0.002), 40-49 years (Humana: OR = 3.80, P < 0.001), 50-59 years (Humana: OR = 1.99, P = 0.027), and < 64 years (Medicare: OR = 1.74, P < 0.001) were risk factors for revision arthroscopy. Obesity (Humana: OR = 1.64, P < 0.001; Medicare: OR = 1.37, P < 0.001), morbid obesity (Medicare: OR = 1.20, P < 0.001), age 70-74 (Medicare: OR = 1.12, P < 0.001), 75-79 (Medicare: OR = 1.25, P < 0.001), 80-84 (Medicare: OR = 1.20, P < 0.001), and concomitant osteoarthritis (Humana: OR = 1.42, P < 0.001; Medicare: OR = 1.46, P < 0.001) were risk factors for conversion to TKA. CONCLUSIONS: Medicare and Humana databases showed that 0.92%-3.01% and 4.79%-9.47% of patients undergo revision arthroscopy or conversion to TKA within a year of isolated meniscectomy. Obesity was a risk factor for early revision arthroscopy and conversion to TKA, whereas concomitant osteoarthritis was a risk factor for conversion to TKA. LEVEL OF EVIDENCE: Level III, retrospective comparative trial.

The Evolution of Cryoneurolysis for the Treatment of Shoulder, Hip, and Knee Pain: Where Are We Now and Where Will We Go? A Systematic Review.

Cryoneurolysis, otherwise known as cryoanalgesia, is a process of addressing nerve-related pain via disruption of nerve conduction utilizing extreme cold temperatures. Throughout the literature, cryoneurolysis has been described for decades across various specialties. Within the past few years, a growing movement of its application within orthopedics has provided pain relief solutions in both the non-surgical and surgical space. A review of the literature utilizing multiple medical search engines was performed to identify relevant orthopedic articles related to the treatment of joint pain with cryoneurolysis or cryoanalgesia. A review of the cryoneurolysis, indications, efficacy, and treatment gaps within the literature were identified to provide guidance for future research.

Identification of the Sensory Dependent Locations of the Shoulder Joint to Optimize Surgical Approaches and Reduce Postoperative Pain: A Systematic Review.

INTRODUCTION: Treatment of post-surgical pain is predicated by an understanding of pain generators. The purpose of this review is to identify sensory dependent areas of the shoulder and discuss their correlation in treating postoperative pain. MATERIALS AND METHODS: Pubmed, Embase, and Cochrane Database of Systemic Reviews were searched (key terms: "Nociception" or "sensory pain receptors" or "pain map" or "neuroanatomy and shoulder" or "rotator cuff") to identify studies in the current literature (1966-2018) regarding sensory innervation of the shoulder and rotator cuff. The search was limited to the English language, human studies, and publication types to reviews and clinical studies. Articles written in other languages besides English, animal studies, abstracts, and conference notes were excluded. Each search result was investigated for relevant physiological information of the nerve endings and nociceptors as well as pertinent information and figures that illustrated the location of the identified receptors. RESULTS: A total of 12 articles were identified that addressed the sensory innervation of the shoulder. The shoulder capsule has the highest sensory nerve density. The attachment sites between the labrum and the capsule and glenoid rim were also found to be highly sensory dependent, in contrast to the peri-core zone at the capsulolabral junction, which was found to be less concentrated with fascicles and sensory nerve endings. The subacromial bursa is also a highly sensory dependent structure, with a more concentrated neural network on the coracoacromial side compared to other quadrants of the bursa. Cutaneous locations of sensory fibers on the shoulder are best defined by mapping the pressure pain threshold (PPT) of various locations on the shoulder. The most sensory dependent locations of the shoulder were found to be the posterior border of the acromion, the glenohumeral joint, the anterior deltoid, and the upper trapezius. CONCLUSION: This review examined the origin of pain in the shoulder, the location of cutaneous pain receptors, and receptors in each major part of the shoulder. Providing analgesia to these densely innervated areas of the shoulder can potentially reduce pain associated with surgical trauma. In addition, knowledge of the sensory dependent areas of the shoulder may elicit consideration of alternative incision sites and surgical protocols to decrease the insult to nociceptors in these locations. These changes could possibly decrease the narcotic requirement in the postoperative period.

Chondrotoxicity of Local Anesthetics: Liposomal Bupivacaine Is Less Chondrotoxic than Standard Bupivacaine.

OBJECTIVE: The purpose of this study is to determine whether (1) liposomal bupivacaine is chondrotoxic; (2) the chondrotoxicity of liposomal bupivacaine differs from standard bupivacaine; and (3) chondrotoxic effects are time dependent. MATERIALS AND METHODS: We obtained 72 10 mm articular cartilage plugs from 12 fresh bovine distal femoral knee joints and exposed them to either saline, 0.5% bupivacaine, or liposomal bupivacaine for either 30 or 90 minutes. Twenty-four hours after treatment, chondrocyte viability was measured with the use of a fluorescent live/dead assay. An ANOVA test of variance was performed followed by a Holm-Sidak test to make pairwise comparisons across conditions. Student's t-test was used to compare means. RESULTS: Percent viability of cells exposed to liposomal bupivacaine for 30 minutes was less versus saline control (53.9% ± 21.5% vs. 73.7 ± 18.4%, p=0.035), and this remained significant at 90 minutes (49.1% ± 20.3% vs. 67.2% ± 25.6%, p < 0.001). Liposomal bupivacaine had less chondrotoxic effects when compared with bupivacaine after 90 minutes, with greater viability (49.1% ± 20.3% vs. 21.4% ± 14.0%, p=0.003). Chondrotoxicity was found to be time dependent within the bupivacaine group (percent viability at 30 min: 45.5 ± 18.2%, 90 min: 21.4 ± 14.0%, p=0.001); however, liposomal bupivacaine did not demonstrate a significant time-dependent chondrotoxic relationship (p=0.583). CONCLUSIONS: Bupivacaine and liposomal bupivacaine are both toxic to chondrocytes. Liposomal bupivacaine is less chondrotoxic than standard bupivacaine and does not demonstrate a time-dependent toxicity.