Editorial Commentary: Acromioclavicular Joint Reconstruction With Double-Bundle Constructs Provides Improved Maintenance of Reduction but Comparable Clinical Outcomes Versus Single-Bundle Constructs.

Treatment of acute acromioclavicular (AC) joint separations is dependent on a variety of factors, including severity, acuity, patient demographics, activity level, and surgeon preferences. For more severe or unstable separations (Rockwood types IIIB, IV, V, and VI), surgical intervention is typically recommended. Over 160 surgical techniques have been described, but none have emerged as a gold standard. Arthroscopic-assisted or all-arthroscopic fixation of the coracoclavicular ligaments with suture buttons has become increasingly popular due to lower complication rates compared with more rigid fixation. Configurations include single-bundle (SB) constructs and double-bundle (DB) configurations that more anatomically reconstruct the conoid and trapezoid ligaments but with longer operative times. Clinical studies with short-term follow-up have demonstrated improved maintenance of fixation for DB compared with SB constructs but no significant differences in clinical outcomes. In our experience, SB suture button-only constructs lead to unacceptable failures due to loss of reduction. We recommend either a single suture button construct augmented with allograft or DB suture button constructs for the treatment of acute AC joint separations.

Glenoid structural bone grafting in reverse total shoulder arthroplasty: clinical and radiographic outcomes.

BACKGROUND: Current options for reconstruction of large glenoid defects in reverse total shoulder arthroplasty (RTSA) include structural bone grafting, use of augmented components, or 3D-printed custom implants. Given the paucity in the literature on structural bone grafts in RTSA, this study reflects our experience on clinical and radiographic outcomes of structural bone grafts used for glenoid defects in RTSA. METHODS: We identified 33 consecutive patients who underwent RTSA using structural bone grafts for glenoid bone loss between 2008 and 2019. Twenty-six patients with a mean clinical follow-up of 4.4 ± 3.9 years and a mean radiographic follow-up of 2.7 ± 3.2 years were included. Patient demographic data, perioperative functional outcomes, radiographic outcomes, complications, and reoperation rates were determined. RESULTS: Between 2008 and 2019, 26 RTSAs were performed using structural autograft or allograft for glenoid defects. There were 20 females (77%) and 6 males (23%), with a mean presenting age of 68 years (range 41-86), mean BMI of 29 (range 21-44), and mean Charlson Comorbidity Index of 3 (range 0-8). There were 19 cases of central glenoid defects, and 7 were combined central and peripheral defects. Structural grafts included humeral head autograft (7), proximal humerus autograft (7), iliac crest autograft (7), distal clavicle autograft (2), and femoral head allograft (3). All 18 revision RTSA cases had simultaneous humeral-sided revision. There was significant postoperative improvement in American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form scores (27.0 ± 12.6 preoperation vs. 59.8 ± 24.1 postoperation; P < .001) and visual analog scale scores (8.1 ± 3.6 preoperation vs. 3.0 ± 3.2 postoperation; P < .001). Range of motion improved significantly for active forward elevation (63° ± 36° preoperation vs. 104° ± 36° postoperation; P < .001) and external rotation (21° ± 20° preoperation vs. 32° ± 23° postoperation, P = .036). Eighty-eight percent of cases (23 of 26) had successful reconstruction of the glenoid, defined as no visible radiolucent lines nor glenoid component migration at final follow-up. The reoperation rate was 19% (5 of 26). Postoperative complications included 2 cases of acromial stress fractures that were treated nonoperatively, for a total complication rate (including reoperation) of 27% (7 of 26 cases). CONCLUSIONS: The use of structural bone autografts and allografts in RTSA was associated with improved outcome scores and range of motion. A reoperation rate of 19% and total complication rate of 27% were reported for these challenging cases. However, 86% of these complications were not related to structural glenoid reconstruction failure. Structural grafts are a reasonable option for glenoid reconstruction in RTSA cases with glenoid bone loss.

Knee MRI: Meniscus Roots, Ramps, Repairs, and Repercussions.

Menisci play an essential role in maintaining normal pain-free function of the knee. While there are decades of MRI literature on the tears involving the meniscus body and horns, there is now a surge in knowledge regarding injuries at the meniscus roots and periphery. The authors briefly highlight new insights into meniscus anatomy and then summarize recent developments in the understanding of meniscus injuries that matter, emphasizing meniscus injuries at the root and peripheral (eg, ramp) regions that may be missed easily at MRI and arthroscopy. Root and ramp tears are important to diagnose because they may be amenable to repair. However, if these tears are left untreated, ongoing pain and accelerated cartilage degeneration may ensue. The posterior roots of the medial and lateral menisci are most commonly affected by injury, and each of these injuries is associated with distinctive clinical profiles, MRI findings, and tear patterns. Specific diagnostic pitfalls can make the roots challenging to evaluate, including MRI artifacts and anatomic variations. As with root tears, MRI interpretation and orthopedic treatment have important differences for injuries at the medial versus lateral meniscus (LM) periphery (located at or near the meniscocapsular junction). Medially, ramp lesions typically occur in the setting of an anterior cruciate ligament rupture and are generally classified into five patterns. Laterally, the meniscocapsular junction may be injured in association with tibial plateau fractures, but disruption of the popliteomeniscal fascicles may also result in a hypermobile LM. Updated knowledge of the meniscus root and ramp tears is crucial in optimizing diagnostic imaging before repair and understanding the clinical repercussions. ©RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available in the Online Learning Center.

Return-to-play and performance after operative treatment of Achilles tendon rupture in elite male athletes: a scoping review.

OBJECTIVE: To examine the current evidence regarding return-to-play (RTP) and performance after Achilles tendon rupture in elite athletes treated with operative intervention. DESIGN: Scoping review. DATA SOURCES: Published sources identified through a PubMed search of elite athletes, defined as professional or division one collegiate athletes in baseball, basketball, American football or soccer. METHODS: Our search yielded a total of 2402 studies, with 13 studies fulfilling the study criteria of reporting elite athletes with objective measures of their athletic performance. A total of 709 elite athletes were included from the NBA, NFL, Major League Baseball (MLB), National Collegiate Athletic Association (NCAA) football and professional soccer. RESULTS AND DISCUSSION: Overall, 61%-100% of elite male athletes RTP after Achilles tendon rupture and operative repair. NBA players had inferior performance compared with their preoperative status as well as controls of non-injured players. Studies did not show significantly different performance after Achilles injury for MLB players. Professional soccer, NFL and NCAA football studies reported varying performance after injury. CONCLUSIONS: Evidence suggests that sports with explosive plantarflexion demands, such as basketball, may be associated with a greater decrease in performance despite operative intervention after Achilles rupture.

Editorial Commentary: Soaking Anterior Cruciate Ligament Grafts in Vancomycin Solution Lowers Infection Rates Without Lowering Functional Outcomes.

Soaking anterior cruciate ligament grafts in vancomycin solution is done by many surgeons. Research has indicated decreased infection rates and similar anterior cruciate ligament retear rates between grafts soaked in vancomycin solution before implantation versus those without. In addition, there has been basic science evidence for tenocyte survival and viability even when exposed to vancomycin solution. The next frontier, investigating the maturation of vancomycin-soaked grafts with advanced imaging, may cause some surgeons to reconsider the practice but should not stop it, based on the available literature.

Arthroscopic Single and Double Row Repair of Isolated and Combined Subscapularis Tears Result in Similar Improvements in Outcomes: A Systematic Review.

PURPOSE: To systematically review the literature to (1) describe arthroscopic subscapularis repair constructs and outcomes in patients with isolated and combined subscapularis tears and (2) compare outcomes after single- and double-row subscapularis repair in both of these settings. METHODS: A systematic review was performed using PRISMA guidelines. PubMed, SCOPUS, and Cochrane Central Register of Controlled Trials were searched for Level I-IV evidence studies that investigated outcomes after arthroscopic subscapularis repair for the treatment of isolated subscapularis tears or subscapularis tears combined with posterosuperior rotator cuff tears in adult human patients. Data recorded included study demographics, repair construct, shoulder-specific outcome measures, and subscapularis retears. Study methodological quality was analyzed using the MINORS score. Heterogeneity and low levels of evidence precluded meta-analysis. RESULTS: The initial search yielded 811 articles (318 duplicates, 493 screened, 67 full-text review). Forty-three articles (2406 shoulders, 57% males, mean age range 42 to 67.5 years, mean MINORS score 13.4 ± 4.1) were included and analyzed. Articles reported on patients with isolated subscapularis tears (n = 15), combined tears (n = 17), or both (n = 11). The majority of subscapularis repairs used single-row constructs (89.4% of isolated tears, 88.9% of combined tears). All except for one study reporting on outcome measures found clinically significant improvements after subscapularis repair, and no clinically significant differences were detected in 5 studies comparing isolated to combined tears. Subscapularis retear rates ranged from 0% to 17% for isolated tears and 0% to 32% for combined subscapularis and posterosuperior rotator cuff tears. Outcomes and retear rates were similar in studies comparing single-row to double-row repair for isolated and combined subscapularis tears (P > .05 for all). CONCLUSION: Arthroscopic subscapularis repair resulted in significant improvements across all outcome measures, regardless of whether tears were isolated or combined or if repairs were single or double row. LEVEL OF EVIDENCE: Level IV, systematic review of Level II-IV studies.

Biomechanical, Histologic, and Micro-Computed Tomography Characterization of Partial-Width Full-Thickness Supraspinatus Tendon Injury in Rats.

PURPOSE: Partial rotator cuff tears can cause shoulder pain and dysfunction and are more common than complete tears. However, few studies examine partial injuries in small animals and, therefore a robust, clinically relevant model may be lacking. This study aimed to fully characterize the established rat model of partial rotator cuff injury over time and determine if it models human partial rotator cuff tears. METHODS: We created a full-thickness, partial-width injury at the supraspinatus tendon-bone interface bilaterally in 31 Sprague-Dawley rats. Rats were euthanized immediately, and at 2-, 3-, 4-, and 8-weeks after surgery. Fourteen intact shoulders were used as controls. Samples were assessed biomechanically, histologically, and morphologically. RESULTS: Biomechanically, load to failure in controls and 8 weeks after injury was significantly greater than immediately and 3 weeks after injury. Load to failure at 8 weeks was comparable to control. However, the locations of failure were different between intact shoulders and partially injured samples. Bone mineral density at 8 weeks was significantly greater than that at 2 and 3 weeks. Although no animals demonstrated propagation to complete tear and the injury site remodeled histologically, the appearance at 8 weeks was not identical to that in the controls. CONCLUSIONS: The biomechanical properties and bone quality decreased after the injury and was restored gradually over time with full restoration by 8 weeks after injury. However, the findings were not equivalent to the intact shoulder. This study demonstrated the limitations of the current model in its application to long-term outcome studies, and the need for better models that can be used to assess chronic partial rotator cuff injuries. CLINICAL RELEVANCE: There is no small animal model that mimics human chronic partial rotator cuff tears, which limits our ability to improve care for this common condition.

Outcomes after resection arthroplasty versus permanent antibiotic spacer for salvage treatment of shoulder periprosthetic joint infections: a systematic review and meta-analysis.

BACKGROUND: Although revision to new components is favored after shoulder periprosthetic joint infections (PJIs), implant exchange is not always feasible. In certain cases, definitive treatment may be retainment of an antibiotic spacer or resection arthroplasty. The purpose of this investigation was to systematically review the literature for studies reporting on outcomes after resection arthroplasty or permanent antibiotic spacer for salvage treatment of shoulder PJIs. METHODS: A systematic review was performed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, SCOPUS, and Cochrane Central Register of Controlled Trials were searched for Level I-IV studies that reported on the final treatment of periprosthetic shoulder infections using resection arthroplasty or a permanent antibiotic spacer. Data recorded included study demographics, causative infectious organism, shoulder-specific range of motion and outcome measures, and infection eradication rate. Study methodological quality was analyzed using the Methodological Index for Non-Randomized Studies score. Forest plots of proportions and meta-analyses of single means were generated for infection eradication rates and outcomes, respectively. Heterogeneity was quantified using the I2 statistic. A P value of .05 was set as significant. RESULTS: The initial search yielded 635 articles (211 duplicates, 424 screened, 57 full-text review). Twenty-three articles (126 resection arthroplasty and 177 retained antibiotic spacer patients, 51% females, mean age range 37-78.5 years, mean Methodological Index for Non-Randomized Studies score 9.6 ± 0.7) were included and analyzed. The pooled infection eradication rate was 82% (72%-89%) after resection arthroplasty and 85% (79%-90%) after permanent antibiotic spacer. The pooled mean forward flexion (71.5° vs. 48.7°; P < .001) and mean American Shoulder and Elbow Surgeons score (53.5 vs. 31.0; P < .001) were significantly higher for patients treated with a permanent antibiotic spacer compared with resection arthroplasty. No significant differences were found for mean external rotation (13.5° vs. 20.5°; P = .07), abduction (58.2° vs. 50.3°; P = .27), or visual analog scale pain (3.7 vs. 3.4; P = .24) between groups. There was a statistically significant, but not clinically significant, difference in mean Constant score between permanent antibiotic spacer and resection arthroplasty patients (33.6 vs. 30.0; P < .001). CONCLUSION: When implant exchange after shoulder PJI is not feasible, permanent antibiotic spacers and resection arthroplasty are both salvage procedures that provide similar rates of infection eradication. Although both can decrease pain levels, the permanent antibiotic spacer may result in better functional outcomes compared with resection arthroplasty.

Revision ulnar collateral ligament reconstruction in Major League Baseball pitchers: effects of fastball velocity and usage.

BACKGROUND: Ulnar collateral ligament (UCL) tears are prevalent in Major League Baseball (MLB) pitchers and can cause significant loss of time with varying reports of impact on performance. Revision UCL reconstruction (UCLR) is becoming increasingly common, with little known about the effects on fastball (FB) velocity and usage (FB%) in this setting. HYPOTHESIS/PURPOSE: The purpose was to evaluate the effect of revision UCLR on MLB pitchers with respect to postoperative FB velocity and FB% at 1 and 2 years after return to play. The hypothesis was postoperative FB velocity and FB% would significantly decrease vs. prerevision levels, and that revision UCLRs would result in significantly decreased FB velocity and FB% in comparison to a matched group of MLB pitchers after primary UCLR. METHODS: Twenty-one pitchers who underwent revision UCLR and returned to MLB play were identified from public records from 2008-2021. The PITCHf(x) system collected FB velocity for 4-seam (4FB) and 2-seam (2FB) fastballs and total FB% for pitchers in the prerevision year as well as the 2 years after return. A matched control group of pitchers who underwent primary UCLR was used for comparison. RESULTS: There were no significant differences in FB velocity between prerevision levels (4FB 92.9 mph, 2FB 91.4 mph) and years 1 (4FB 92.5 mph, 2FB 91.2 mph) and 2 (4FB 93.4 mph, 2FB 91.1 mph) after revision UCLR. FB% decreased from the prerevision season (60.1) and the first (56.2, P = .036) and second years (52.5, P = .002) after return. There were no significant differences between FB velocity and FB% or between the revision and primary UCLR groups. CONCLUSION: Pitchers returning to the MLB level after revision UCLR can expect similar FB velocity to their prerevision FB velocity and to pitchers undergoing primary UCLR; however, they do demonstrate a decrease in FB%, which may suggest less confidence in their FB after RTP.

Significantly Lower Infection Risk for Anterior Cruciate Ligament Grafts Presoaked in Vancomycin Compared With Unsoaked Grafts: A Systematic Review and Meta-analysis.

PURPOSE: To compare postoperative infection rates following ACL reconstruction performed with grafts presoaked in vancomycin versus those without vancomycin. METHODS: A systematic review was performed using PRISMA guidelines. PubMed, SCOPUS, and Cochrane Central Register of Controlled Trials were searched for therapeutic level I to III studies that compared outcomes of presoaking ACL grafts with vancomycin versus without vancomycin in human patients. Included graft types were tendon autografts or allografts, and included studies documented infection with a minimum follow-up of 30 days. Postoperative infection rates and knee-specific patient-reported outcome scores were extracted from each study and compared between groups. Study methodological quality was analyzed using the Methodological Index for Non-Randomized Studies (MINORS) and Modified Coleman Methodology Score (MCMS). Infection rates and retear rates were pooled and weighted for meta-analysis using a random-effects model. All P values were reported with an α level of 0.05 set as significant. RESULTS: The initial search yielded 144 articles (44 duplicates, 100 screened, 29 full-text review). Ten articles (21,368 subjects [7,507 vancomycin and 13,861 no vancomycin], 67% males, mean ± standard deviation age 29.5 ± 1.5 years) were included and analyzed. Eight of the 10 studies included only autografts, with 94.5% of grafts being hamstring autografts. Soaking grafts in vancomycin resulted in significantly fewer infections (0.013% versus 0.77%; odds ratio 0.07; 95% confidence interval 0.03, 0.18; P < .001). Only 2 studies included patient-reported outcomes, and both demonstrated no difference in International Knee Documentation Committee scores 1 year after surgery for patients with grafts presoaked in vancomycin versus without vancomycin. CONCLUSIONS: Soaking ACL tendon grafts with vancomycin before implantation is associated with a nearly 15 times decrease in odds of infection compared with grafts not soaked in vancomycin. Few studies investigated patient-reported outcomes and retear rates after soaking ACL grafts in vancomycin. LEVEL OF EVIDENCE: III, systematic review of level III studies.

Administrative Databases Used for Sports Medicine Research Demonstrate Significant Differences in Underlying Patient Demographics and Resulting Surgical Trends.

PURPOSE: To discern differences between the PearlDiver and MarketScan databases with regards to patient demographics, costs, reoperations, and complication rates for isolated meniscectomy. METHODS: We queried the PearlDiver Humana Patient Records Database and the IBM MarketScan Commercial Claims and Encounters database for all patients who had record of meniscectomy denoted by Current Procedure Terminology 29880 or 29881 between January 1, 2007, and December 31, 2016. Those that had any other knee procedure at the same time as the meniscectomy were excluded, and the first instance of isolated meniscectomy was recorded. Patient demographics, Charlson Comorbidity Index, reoperations, 30- and 90-day complication rates, and costs were collected from both databases. Pearson's χ2 test with Yate's continuity correction and the Student t test were used to compare the 2 databases, and an alpha value of 0.05 was set as significant. RESULTS: We identified 441,147 patients with isolated meniscectomy from the MarketScan database (0.36% of total database), approximately 10 times the number of patients (n = 49,924; 0.20% of total database) identified from PearlDiver. The PearlDiver population was significantly older (median age: 65-69) than the MarketScan cohort, where all patients were younger than 65 (median age: 52; P < .001). Average Charlson Comorbidity Index was significantly lower for MarketScan (0.172, standard deviation [SD]: 0.546) compared with PearlDiver (1.43, SD: 2.05; P < .001), even when we restricted the PearlDiver cohort to patients younger than 65 years (1.02, SD: 1.74; P < .001). The PearlDiver <65 years subcohort also had increased 30- (relative risk 1.53 [1.40-1.67]) and 90-day (relative risk 1.56 [1.47-1.66]) postoperative complications compared with MarketScan. Overall, laterality coding was more prevalent in the PearlDiver database. CONCLUSIONS: For those undergoing isolated meniscectomy, the MarketScan database comprised an overall larger and younger cohort of patients with fewer comorbidities, even when examining only subjects younger than 65 years of age. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Superior Capsular Reconstruction: A Systematic Review of Surgical Techniques and Clinical Outcomes.

PURPOSE: To evaluate surgical techniques and clinical outcomes of arthroscopic superior capsular reconstruction (SCR) for the treatment of massive irreparable rotator cuff tears. METHODS: A systematic review was registered with PROSPERO and performed using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines. The PubMed, Scopus, and Cochrane databases were searched. Studies investigating SCR with reported surgical techniques were included. Animal studies, cadaveric studies, review studies, and letters to the editor were excluded. The technical aspects of the surgical techniques for SCR were analyzed in each article, which included graft type, glenoid fixation method, greater tuberosity fixation method, graft passage technique, suture management, margin convergence, concomitant procedures, and postoperative rehabilitation protocol. Clinical outcomes, when available, were also analyzed. RESULTS: We screened 365 articles, of which 29 described surgical techniques for SCR. According to the Modified Coleman Methodology Score, 24 articles were rated as poor (score < 55), 4 were rated as fair (score between 55 and 69), and 1 was rated as good (score between 70 and 84), with an average score of 25.8 ± 20.9. The most commonly performed technique for SCR used the following: an acellular dermal allograft, 2 biocomposite suture anchors for glenoid fixation, transosseous-equivalent double-row suture anchor fixation for greater tuberosity fixation with 2 biocomposite medial-row anchors and 2 biocomposite lateral-row anchors, the double-pulley technique combined with an arthroscopic grasper and/or pull suture to pass the graft into the shoulder, the performance of both anterior and posterior margin convergence, and a native rotator cuff repair when possible. Only 8 studies reported clinical outcomes, and they showed that SCR provides significant improvement in patient-reported outcomes, significant improvement in shoulder range of motion, variable graft failure rates, low complication rates, and variable reoperation rates. There were no studies comparing outcomes among the various surgical techniques. CONCLUSIONS: Many surgical techniques exist for arthroscopic SCR. However, no superior technique was shown because there were no studies comparing clinical outcomes among these various techniques. LEVEL OF EVIDENCE: Level V, systematic review of Level III, IV, and V studies.

Inflammatory Mechanisms in the Development of Osteoarthritis.

Osteoarthritis was traditionally thought of as a noninflammatory disease, but improved molecular techniques have recognized a significant inflammatory component. An initial joint injury or biomechanical imbalance leads to local tissue damage and inflammation, which is propagated by the innate immune system. The production of damage-associated molecular patterns (DAMPs) results in the activation of immune-modulated mechanisms, leading to the production of catabolic factors that can damage native joint structures such as cartilage. DAMPs may originate from extracellular matrix degradation products, intracellular components of lysed cells, complement, or joint crystals-even plasma proteins can enter through an inflamed synovium and further perpetuate the inflammatory process. Therapeutic interventions have traditionally focused on symptom management; however, there is potential for pharmacologic modification of the disease process in osteoarthritis through novel anti-inflammatory agents.

Surgeon practice patterns for pre-soaking ACL tendon grafts in vancomycin: a survey of the ACL study group.

PURPOSE: To survey members of The ACL study group to determine the current practice patterns surrounding the technique of pre-soaking ACL grafts in vancomycin. METHODS: A web-based questionnaire was distributed to members of the ACL Study Group. Questions included the use of vancomycin solution for graft soaking during ACL reconstruction, their protocol for soaking the graft, vancomycin concentration utilized, graft choices, and concerns with the technique. RESULTS: Sixty-six (57%) ACL surgeons completed the survey. Approximately one-third (37.9%) of respondents currently pre-soak their ACL grafts in vancomycin prior to implantation, with 60% of these surgeons being from Europe. Seventy-six percent have adopted this practice within the past 5 years. The majority of surgeons wrap the graft in a vancomycin-soaked gauze prior to implantation (56%), soak for a variable amount of time before implantation (56%), use a concentration of 5 mg/mL (68%), and soak hamstring grafts (92%). Concerns included the mechanical properties of the graft (35%), cost of vancomycin (23%), availability (12%), and antibiotic resistance (9%). CONCLUSION: This survey demonstrates that 37.9% of ACL study group members currently utilize vancomycin to pre-soak ACL tendon grafts as a means to decrease post-operative infection risk, with the majority of surgeons having implemented this practice within the past 5 years. The biggest concern towards using vancomycin was the mechanical properties of the graft after soaking. LEVEL OF EVIDENCE: IV.

Pain management in shoulder arthroplasty: a systematic review and network meta-analysis of randomized controlled trials.

BACKGROUND: Postoperative pain management after total shoulder arthroplasty (TSA) can be challenging. Given the variety of pain management options available, the purpose of this investigation was to systematically review the literature for randomized controlled trials reporting on pain control after shoulder arthroplasty. We sought to determine which modalities are most effective in managing postoperative pain and reducing postoperative opioid use. METHODS: A systematic review was performed using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines. PubMed, Scopus, and the Cochrane Central Register of Controlled Trials were searched for Level I-II randomized controlled trials that compared interventions for postoperative pain control after TSA. Pain control measures included nerve blocks and nerve block adjuncts, local injections, patient-controlled analgesia, oral medications, and other modalities. The 2 primary outcome measures were pain level measured on a 0-10 visual analog scale and opioid use. The risk of study bias and methodologic quality were analyzed using The Cochrane Collaboration's Risk of Bias 2 (RoB 2) tool. Network meta-analyses were performed for visual analog scale pain scores at postsurgical time points and opioid use using a frequentist approach and random-effects model, with heterogeneity quantified using the I2 statistic. Treatments were ranked using the P score, and statistical significance was set at P < .05. RESULTS: The initial search yielded 2391 articles (695 duplicates, 1696 screened, 53 undergoing full-text review). Eighteen articles (1358 shoulders; 51% female patients; mean age range, 65-73.7 years; 4 studies with low risk of bias, 12 with some risk, and 2 with high risk) were included and analyzed. At 4 and 8 hours postoperatively, patients receiving local liposomal bupivacaine (LB) injection (P < .001 for 4 and 8 hours) or local ropivacaine injection (P < .001 for 4 hours and P = .019 for 8 hours) had significantly more pain compared with patients who received either a continuous interscalene block (cISB) or single-shot interscalene block (ssISB). No differences in opioid use (at P < .05) were detected between modalities. The P scores of treatments demonstrated that ssISBs were most favorable at time points < 24 hours, whereas pain at 24 and 48 hours after surgery was best managed with cISBs or a combination of an ssISB with a local LB injection. CONCLUSION: Interscalene blocks are superior to local injections alone at managing pain after TSA. Single-shot interscalene blocks are optimal for reducing early postoperative pain (< 24 hours), whereas pain at 24-48 hours after surgery may be best managed with cISBs or a combination of an ssISB with a local LB injection.

Exogenous micro-RNA and antagomir modulate osteogenic gene expression in tenocytes.

Tendinopathy is a common and disabling condition that is difficult to treat. The pathomolecular events behind tendinopathy remain uncertain. Micro-RNAs (miRNAs, miRs) are short non-coding RNAs that regulate gene expression and may play a role in tendinopathy development. Tenocytes were obtained from human patellar tendons in patients undergoing anterior cruciate ligament (ACL) reconstruction. Micro-RNA mimics and antagomirs for miR-30d, 26a, and 29a were separately transfected into tenocyte culture. Gene expression for scleraxis, collagen 1 alpha 1 (COL1A1), collagen 3 alpha 1 (COL3A1), interleukin-1-beta (IL-1ß), interleukin-6 (IL-6), bone morphogenic protein 2 (BMP2), bone morphogenic protein 12 (BMP12), and osteocalcin was determined for each miRNA mimic and antagomir transfection using real-time quantitative PCR (qPCR). The results showed that exogenous miR-29a downregulated BMP2 and BMP12, while miR-26a and miR-30d did not have a significant effect on tenocyte gene expression. These findings suggest miR-29a contributes to tendon homeostasis and can serve as a potential therapeutic target in treating tendinopathy.

Editorial Commentary: Please Don't Call It a Mesenchymal Stem Cell.

One of the holy grails in orthopedics, and for medicine in general, is to have easy access to an immediately available and viable source of progenitor cells for use in tissue regeneration. The use of the term "mesenchymal stem cell" has been called into question, as it has historically represented a wide variety of tissue-specific cell types, only some of which can be categorized as true stem cells. More recent literature has better defined the characteristics of a stem cell, yet the landscape is still littered with unsubstantiated claims of cures for many human diseases, both within orthopaedic surgery as well as other fields of medicine. Although attention is needed to more carefully define the characteristics of the cells under investigation in any particular line of research, significantly more work will be involved to learn the biological mechanisms and signaling involved in coaxing these cells into in vivo tissue regeneration.

Reoperation Rates Following Meniscus Transplantation Using the Truven Database.

PURPOSE: The purpose of this study was to determine the (1) reoperation rate and (2) 30-day complication rate in a large insurance database. METHODS: The Truven Database was queried for subjects that underwent meniscus allograft transplantation (Current Procedural Terminology code 29868) in the outpatient setting with minimal 2-year follow-up. Patients without confirmed laterality and patients that underwent concomitant ligament reconstruction were excluded. Reoperation was defined by ipsilateral knee procedure after the index surgery. The 30-day postoperative complication rates were assessed using International Classification of Diseases, 9th Revision, Clinical Modification codes. RESULTS: A total of 284 patients (mean age of 26.2 ± 10.4 years; 49.6% females) were included in this study with mean follow up of 43.2 ± 19.2 months. One hundred and sixty-seven subjects (58.8%) undergoing meniscus allograft transplantation underwent reoperation at an average of 11.9 ± 12.2 months postoperatively. There was a low number of subjects that required ipsilateral unicompartmental knee arthroplasty and total knee arthroplasty postoperatively (0.7% and 1.1%, respectively). The overall 30-day complication rate following meniscus allograft transplantation was 1.4%. CONCLUSIONS: Patients undergoing meniscus allograft transplantation have a 58.8% reoperation rate at final follow up with low (1.4%) 30-day complication rates in a large insurance database. LEVEL OF EVIDENCE: Level IV, case series.

Human Tendon-Derived Collagen Hydrogel Significantly Improves Biomechanical Properties of the Tendon-Bone Interface in a Chronic Rotator Cuff Injury Model.

PURPOSE: Poor healing of the tendon-bone interface (TBI) after rotator cuff (RTC) tears leads to high rates of recurrent tear following repair. Previously, we demonstrated that an injectable, thermoresponsive, type I collagen-rich, decellularized human tendon-derived hydrogel (tHG) improved healing in an acute rat Achilles tendon injury model. The purpose of this study was to investigate whether tHG enhances the biomechanical properties of the regenerated TBI in a rat model of chronic RTC injury and repair. METHODS: Tendon hydrogel was prepared from chemically decellularized human cadaveric flexor tendons. Eight weeks after bilateral resection of supraspinatus tendons, repair of both shoulders was performed. One shoulder was treated with a transosseous suture (control group) and the other was treated with a transosseous suture plus tHG injection at the repair site (tHG group). Eight weeks after repair, the TBIs were evaluated biomechanically, histologically, and via micro-computed tomography (CT). RESULTS: Biomechanical testing revealed a larger load to failure, higher stiffness, higher energy to failure, larger strain at failure, and higher toughness in the tHG group versus control. The area of new cartilage formation was significantly larger in the tHG group. Micro-CT revealed no significant difference between groups in bone morphometry at the supraspinatus tendon insertion, although the tHG group was superior to the control. CONCLUSIONS: Injection of tHG at the RTC repair site enhanced biomechanical properties and increased fibrocartilage formation at the TBI in a chronic injury model. CLINICAL RELEVANCE: Treatment of chronic RTC injuries with tHG at the time of surgical treatment may improve outcomes after surgical repair.

Editorial Commentary: The Importance of Capsular Closure in Hip Arthroscopy: Is There a Limit to the Benefit?

Capsular closure is an important concept in hip arthroscopy and should be performed in nearly all patients. However, in patients with stiff hips and borderline arthritic changes, leaving the capsule unrepaired or performing a partial repair in the setting of a T-capsulotomy could result in successful outcomes.