Higher odds of meniscectomy compared with meniscus repair in a young patient population with increased neighbourhood disadvantage.

OBJECTIVES: To investigate the impact of demographic and socioeconomic factors on the management of isolated meniscus tears in young patients and to identify trends in surgical management of meniscus tears based on surgeon volume. METHODS: Data from a large healthcare system on patients aged 14-44 years who underwent isolated meniscus surgery between 2016 and 2022 were analysed. Patient demographics, socioeconomic factors and surgeon volume were recorded. Patient age was categorised as 14-29 years and 30-44 years old. Area Deprivation Index (ADI), a measure of neighbourhood disadvantage with increased ADI corresponding to more disadvantage, was grouped as <25th, 25-75th and >75th percentile. Multivariate comparisons were made between procedure groups while univariate comparisons were made between surgeon groups. RESULTS: The study included 1552 patients treated by 84 orthopaedic surgeons. Older age and higher ADI were associated with higher odds of undergoing meniscectomy. Patients of older age and with non-private insurance were more likely to undergo treatment by a lower-volume knee surgeon. Apart from the year 2022, higher-volume knee surgeons performed significantly higher rates of meniscus repair compared with lower-volume knee surgeons. When controlling for surgeon volume, higher ADI remained a significant predictor of undergoing meniscectomy over meniscus repair. CONCLUSION: Significant associations exist between patient factors and surgical choices for isolated meniscus tears in younger patients. Patients of older age and with increased neighbourhood disadvantage were more likely to undergo meniscectomy versus meniscus repair. While higher-volume knee surgeons favoured meniscus repair, a growing trend of meniscus repair rates was observed among lower-volume knee surgeons. LEVEL OF EVIDENCE: Retrospective cohort study, level III.

Nonanatomic femoral tunnel placement increases the risk of subsequent meniscal surgery after ACLR: Part II-Patients without recurrent ACL injury.

PURPOSE: The purpose of this study was to identify risk factors for subsequent meniscal surgery following anterior cruciate ligament (ACL) reconstruction (ACLR) in patients without recurrent ACL injury. METHODS: Patients aged ≥14 years who underwent primary ACLR with minimum 1-year follow-up and without recurrent ACL injury were retrospectively reviewed. Patient demographics and surgical data at the time of ACLR were collected. Postoperative radiographs were used to measure femoral and tibial tunnel position, and posterior tibial slope. Univariate and multivariate analyses were performed to identify risk factors for subsequent meniscal surgery. RESULTS: Of 629 ACLRs that fulfilled the inclusion criteria, subsequent meniscal surgery was performed in 65 [10.3%] patients. Multivariate analysis revealed that medial meniscal repair at the time of ACLR, younger age, anterior femoral tunnel position and distal femoral tunnel position were significantly associated with subsequent meniscal surgery (p < 0.001, p = 0.016, p = 0.015, p = 0.035, respectively). The frequency of femoral tunnel placement >10% outside of the literature-established anatomic position was significantly higher in those who underwent subsequent meniscal surgery compared to those who did not (38.3% vs. 20.3%, p = 0.006). Posterior tibial slope and ACL graft type were not significantly associated with subsequent meniscal surgery. CONCLUSION: Medial meniscal repair at the time of ACLR, younger age and nonanatomic femoral tunnel placement were risk factors for subsequent meniscal surgery in patients without recurrent ACL injury. Femoral tunnel placement <10% outside of the native anatomic position is important to reduce the risk of subsequent meniscal surgery. LEVEL OF EVIDENCE: Level IV.

Conversion to knee arthroplasty is more common after meniscectomy than meniscus repair in patients older than age 40.

PURPOSE: To describe rates of conversion to unicompartmental or total knee arthroplasty (KA) in patients over the age of 40 years (at initial surgery) after partial meniscectomy (ME) or meniscal repair (MR). METHODS: Patients over the age of 40 undergoing isolated ME or MR between 2016 and 2018 were extracted from a single healthcare provider database. Data on patient characteristics, type of initial surgery, number of returns to the operating room, as well as performed procedures, including conversion to KA, were recorded. Comparative group statistics as well as a Kaplan-Meier survival rate analysis were performed. RESULTS: A total of 3638 patients (47.8% female) were included, with 3520 (96.8%) undergoing ME and 118 (3.2%) MR. Overall, 378 (10.4%) patients returned to the OR at an average of 22.7 ± 17.3 months postoperatively. Conversion to KA was performed more frequently in patients after primary ME (n = 270, 7.7%) compared to those with MR (2.5%, n = 3, odds ratio [OR]: 3.2, p = 0.03). Compared to ME (2.3%, n = 82), two times as many patients undergoing MR returned for subsequent meniscus surgery (MR: 5.9%, n = 7, OR: 2.6, p = 0.02). Time from primary surgery to KA (ME: 22 ± 17 months, MR: 25 ± 15 months, p = 0.96) did not differ between the treatment groups. Survivorship was 95% for ME and 98.2% for MR after 24 months (p = 0.76) and 92.5% and 98.2% after 60 months (p = 0.07), respectively. CONCLUSION: The overall reoperation rate after meniscal surgery was 10.4% in patients over the age of 40 years. Patients treated with primary ME have over three times higher odds to undergo subsequent KA compared to those treated with MR. However, patients with primary MR have a higher rate of subsequent meniscus surgery compared to those undergoing primary ME. This information is important when considering and treating a patient over the age of 40 and meniscal injury. LEVEL OF EVIDENCE: Level III study.

Pseudoparesis and pseudoparalysis in the setting of massive irreparable rotator cuff tear: demographic, anatomic, and radiographic risk factors.

BACKGROUND: The primary purpose of this study was to identify demographic, anatomic, and radiographic risk factors for active forward elevation (AFE) <90° in the setting of massive, irreparable rotator cuff tear (miRCT). The secondary purpose was to identify characteristics differentiating between patients with pseudoparalysis (AFE <45°) and pseudoparesis (AFE >45° but <90°). METHODS: This was a retrospective case-control study reviewing patients with miRCTs at a single institution between January 12, 2016 and November 26, 2020. Patients were separated into 2 cohorts based on presence or absence of preoperative AFE <90° with maintained passive range of motion. Demographics, RCT pattern, and radiographic parameters were assessed as risk factors for AFE <90°. A secondary analysis was conducted to compare patients with pseudoparalysis and pseudoparesis. RESULTS: There were 79 patients in the AFE <90° cohort and 50 patients in the control cohort. Univariate analysis confirmed significant differences between the AFE <90° and control cohort in age (71.9 ± 11.0 vs. 65.9 ± 9.1 years), arthritis severity (34.2% vs. 16.0% grade 3 Samilson-Prieto), acromiohumeral distance (AHD; 4.8 ± 2.7 vs. 7.6 ± 2.6 mm), fatty infiltration of the supraspinatus (3.3 ± 0.9 vs. 2.8 ± 0.8) and subscapularis (2.0 ± 1.2 vs. 1.5 ± 1.0), and proportion of subscapularis tears (55.7% vs. 34.0%). On multivariate analysis, age (odds ratio [OR] 1.08, P = .014), decreased AHD (OR 0.67, P < .001), severe arthritis (OR 2.84, P = .041), and subscapularis tear (OR 6.29, P = .015) were independent factors predictive of AFE <90°. Secondary analysis revealed tobacco use (OR 3.54, P = .026) and grade 4 fatty infiltration of the supraspinatus (OR 2.22, P = .015) and subscapularis (OR 3.12, P = .042) as significant predictors for pseudoparalysis compared to pseudoparesis. CONCLUSIONS: In patients with miRCT, increased age, decreased AHD, severe arthritis, and subscapularis tear are associated with AFE <90°. Furthermore, patients with AFE <90° tend to have greater supraspinatus and subscapularis fatty infiltration. Lastly, among patients with AFE <90°, tobacco use and grade 4 fatty infiltration of the supraspinatus and subscapularis are associated with pseudoparalysis compared with pseudoparesis.

OxPAPC stabilizes liquid-ordered domains in biomimetic membranes.

Long-chain polyunsaturated fatty acids (PUFAs) are prone to nonenzymatic oxidation in response to differing environmental stressors and endogenous cellular sources. There is increasing evidence that phospholipids containing oxidized PUFA acyl chains control the inflammatory response. However, the underlying mechanism(s) of action by which oxidized PUFAs exert their functional effects remain unclear. Herein, we tested the hypothesis that replacement of 1-palmitoyl-2-arachidonyl-phosphatidylcholine (PAPC) with oxidized 1-palmitoyl-2-arachidonyl-phosphatidylcholine (oxPAPC) regulates membrane architecture. Specifically, with solid-state 2H NMR of biomimetic membranes, we investigated how substituting oxPAPC for PAPC modulates the molecular organization of liquid-ordered (Lo) domains. 2H NMR spectra for bilayer mixtures of 1,2-dipalmitoylphosphatidylcholine-d62 (an analog of DPPC deuterated throughout sn-1 and -2 chains) and cholesterol to which PAPC or oxPAPC was added revealed that replacing PAPC with oxPAPC disrupted molecular organization, indicating that oxPAPC does not mix favorably in a tightly packed Lo phase. Furthermore, unlike PAPC, adding oxPAPC stabilized 1,2-dipalmitoylphosphatidylcholine-d6-rich/cholesterol-rich Lo domains formed in mixtures with 1,2-dioleoylphosphatidylcholine while decreasing the molecular order within 1,2-dioleoylphosphatidylcholine-rich liquid-disordered regions of the membrane. Collectively, these results suggest a mechanism in which oxPAPC stabilizes Lo domains-by disordering the surrounding liquid-disordered region. Changes in the structure, and thereby functionality, of Lo domains may underly regulation of plasma membrane-based inflammatory signaling by oxPAPC.

Anatomic Anterior Cruciate Ligament Reconstruction.

Anterior cruciate ligament reconstruction (ACLR) techniques have substantially evolved over the past several decades, driven by evidence that nonanatomic techniques increase the risk for instability, loss of motion, surgical failure, and posttraumatic osteoarthritis. Early techniques used transtibial femoral tunnel drilling, although improved understanding of the anatomy and biomechanics has led to independent femoral tunnel. Anatomic ACLR requires careful consideration of the native ACL dimensions and orientation. Although there is significant variation between patients, understanding of anatomic patterns allows for reliable identification of the ACL footprints and appropriate tunnel positioning, particularly in chronic injuries where the remanent ACL stump is degraded or absent. The femoral tunnel should be placed low and posterior on the lateral femoral condyle using the lateral intercondylar and bifurcate ridges as landmarks. The center of the tibial footprint can be determined by referencing the medial tibial spine and posterior border of anterior horn of lateral meniscus. Measurement of the dimensions of the native ACL and intercondylar notch is also critical for determining graft size and minimizing the risk of impingement, with a goal of reconstructing 50% to 80% of the tibial footprint area. Clinical outcome studies have demonstrated superior anteroposterior and rotatory knee stability with low surgical revision rates (reported between 3% and 5%). By adhering to the principles of anatomic ACLR, surgeons can produce an appropriately sized and located graft for the individual patient, thereby best restoring native knee kinematics and maximizing function. The aim of this infographic is to highlight essential features of anatomic ACLR techniques, which a focus on the native anatomy and surgical planning to achieve an anatomic ACLR.

Harvest location has a minimal impact on differences in cross-sectional area of quadriceps tendon in anterior cruciate ligament reconstruction.

PURPOSE: Anterior cruciate ligament (ACL) reconstruction with quadriceps tendon (QT) has been gaining popularity. However, it is unknown how differences in harvest location of the QT affect its thickness and cross-sectional area (CSA). The present study aimed to clarify the differences in thickness and CSA of the QT based on location of tendon harvesting. METHODS: Patients scheduled for, or who underwent, ACL reconstruction were prospectively included in the study. The short-axis images on ultrasound were used to assess the CSA of the QT at 30 and 60 mm proximal to the superior pole of the patella. QT autografts with CSAs greater than or equal to 10 mm of width were included and measured at three different locations, namely the center, medial one-third, and lateral one-third at the widest diameter of the QT. Patients with less than 10-mm width of the QT at 60 mm proximal to the superior pole of the patella were excluded. The thickness and CSA were compared based on the location of tendon harvest. RESULTS: Thirty-seven patients were recruited for the study. The mean thickness and CSA were larger in the center of the QT compared to the lateral one-third at 30 mm proximal to the superior pole of the patella (thickness, 6.7 ± 1.3 mm vs. 5.9 ± 1.3 mm; P = 0.009; CSA, 65.6 ± 11.4 mm2 vs. 58.8 ± 11.9 mm2; P = 0.036). There were no significant differences in thickness and CSA of the QT among the three assessment locations at 60 mm proximal to the superior pole of the patella (n.s.). CONCLUSION: The thickness and CSA of QT was greater in the center compared to the lateral one-third at 30 mm proximal to the QT insertion point. However, the difference in value was clinically non-significant, and therefore, harvest location of the QT autograft may not meaningfully impact intraoperative graft diameter. As a result, surgeons may choose the harvest location without concern for resultant graft diameter as long as the enough length of QT is secured. LEVEL OF EVIDENCE: III.

Near complete quadriceps tendon healing 2 years following harvest in anterior cruciate ligament reconstruction.

PURPOSE: Despite the recent increase in the use of quadriceps tendon (QT) autograft in anterior cruciate ligament reconstruction (ACLR); however, there remains a paucity of literature evaluating the postoperative morphology of the QT. The present study aimed to determine the postoperative morphologic change of the QT at a minimum of 2 years following harvesting during ACLR. METHODS: Patients who underwent ACLR with QT autograft and underwent magnetic resonance imaging (MRI) at a minimum of 2 years following harvesting were retrospectively included in the study. The anterior-to-posterior (A-P) thickness, medial-to-lateral (M-L) width, cross-sectional area (CSA), and signal/noise quotient (SNQ) of the QT were assessed at 5 mm, 15 mm, and 30 mm proximal to the superior pole of the patella on MRI. The CSA was adjusted by the angle between the QT and the plane of the axial cut based on a cosine function (adjusted CSA). The A-P thickness, M-L width, adjusted CSA, and SNQ were compared pre- and postoperatively. In addition, defects or scar tissue formation in the harvest site were investigated on postoperative MRI. RESULTS: Thirty patients were recruited for the study. The mean duration between postoperative MRI and surgery was 2.8 ± 1.1 years. The mean A-P thickness was 10.3% and 11.9% larger postoperatively at 5 mm and 15 mm, respectively. The mean M-L width was 7.3% and 6.5% smaller postoperatively at 5 mm and 15 mm, respectively. There were no significant differences in the adjusted CSA between pre- and post-operative states (275.7 ± 71.6 mm2 vs. 286.7 ± 91.8 mm2, n.s.). There was no significant difference in the postoperative change in the SNQ of the QT at all assessment locations. Defect or scar tissue formation at the harvest site was observed in 4 cases (13.3%), and 5 cases (16.6%), respectively. CONCLUSION: At a minimum of 2 years following QT harvest during ACLR, the QT became slightly thicker and narrower (approximately 11% and 7%, respectively). While the current study demonstrates that QT re-harvesting can be considered due to nearly normalized tendon morphology, future histological and biomechanical studies are required to determine the re-harvesting potential of the QT. LEVEL OF EVIDENCE: IV.

Early surgery and number of injured ligaments are associated with postoperative stiffness following multi-ligament knee injury surgery: a systematic review and meta-analysis.

PURPOSE: To perform a systematic review and meta-analysis to investigate the rate of stiffness after multi-ligament knee injury (MLKI) surgery and identify potential risk factors associated with postoperative stiffness. METHODS: This study was conducted in accordance with the 2020 PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. Registration was done on the PROSPERO International Prospective Register of Systematic Reviews (CRD42022321849). A literature search of PubMed, Ovid, Embase, and Cochrane Library databases was conducted in October 2022 for clinical studies reporting postoperative stiffness after MLKI surgery. A quality assessment was performed using the Methodological Index of Non-Randomized Studies (MINORS) grading system. The following variables were extracted from studies for correlation to postoperative stiffness: study characteristics, cohort demographics, Schenk classification, neurovascular injury, mechanism of injury, external fixator placement, timing of surgery, and concomitant knee injuries. RESULTS: Thirty-six studies comprising 4,159 patients who underwent MLKI surgery met the inclusion criteria, including two Level-II, fourteen Level-III, and twenty Level-IV studies. The average MINOR score of the studies was 14. The stiffness rate after MLKI was found to be 9.8% (95% CI 0.07-0.13; p < 0.01; I2 = 87%), and the risk of postoperative stiffness was significantly lower for patients with two ligaments injured compared to patients with ≥ 3 ligaments injured (OR = 0.45, 95% CI (0.26-0.79), p = 0.005; I2 = 0%). The results of the pooled analysis showed early surgery (< 3 weeks) resulted in significantly increased odds of postoperative stiffness compared with delayed surgery (≥ 3 weeks) (OR = 2.18; 95% CI 1.11-4.25; p = 0.02; I2 = 0%). However, age, gender, body mass index, energy of injury, and neurovascular injury were not associated with an increased risk of postoperative stiffness (n.s.). CONCLUSION: Performing surgery within the first 3 weeks following MLKI, or concomitant injury of ≥ 3 ligaments, are significantly associated with increased risk of postoperative stiffness. These findings can be utilized by surgeons to decide the timing of surgery for MLKI surgeries especially in which ≥ 3 ligaments are injured. LEVEL OF EVIDENCE: Level IV.

Exploring the potential of ChatGPT as a supplementary tool for providing orthopaedic information.

PURPOSE: To investigate the potential use of large language models (LLMs) in orthopaedics by presenting queries pertinent to anterior cruciate ligament (ACL) surgery to generative pre-trained transformer (ChatGPT, specifically using its GPT-4 model of March 14th 2023). Additionally, this study aimed to evaluate the depth of the LLM's knowledge and investigate its adaptability to different user groups. It was hypothesized that the ChatGPT would be able to adapt to different target groups due to its strong language understanding and processing capabilities. METHODS: ChatGPT was presented with 20 questions and response was requested for two distinct target audiences: patients and non-orthopaedic medical doctors. Two board-certified orthopaedic sports medicine surgeons and two expert orthopaedic sports medicine surgeons independently evaluated the responses generated by ChatGPT. Mean correctness, completeness, and adaptability to the target audiences (patients and non-orthopaedic medical doctors) were determined. A three-point response scale facilitated nuanced assessment. RESULTS: ChatGPT exhibited fair accuracy, with average correctness scores of 1.69 and 1.66 (on a scale from 0, incorrect, 1, partially correct, to 2, correct) for patients and medical doctors, respectively. Three of the 20 questions (15.0%) were deemed incorrect by any of the four orthopaedic sports medicine surgeon assessors. Moreover, overall completeness was calculated to be 1.51 and 1.64 for patients and medical doctors, respectively, while overall adaptiveness was determined to be 1.75 and 1.73 for patients and doctors, respectively. CONCLUSION: Overall, ChatGPT was successful in generating correct responses in approximately 65% of the cases related to ACL surgery. The findings of this study imply that LLMs offer potential as a supplementary tool for acquiring orthopaedic knowledge. However, although ChatGPT can provide guidance and effectively adapt to diverse target audiences, it cannot supplant the expertise of orthopaedic sports medicine surgeons in diagnostic and treatment planning endeavours due to its limited understanding of orthopaedic domains and its potential for erroneous responses. LEVEL OF EVIDENCE: V.

What it takes to have a high-grade pivot shift-focus on bony morphology.

PURPOSE: Variations in femoral and tibial bony morphology have been associated with higher clinical grading and increased quantitative tibial translation, but not tibial acceleration, during the pivot shift test following anterior cruciate ligament (ACL) injury. The purpose of this study was to determine the impact of femoral and tibial bony morphology, including a measurement influenced by both parameters (the Lateral Tibiofemoral Articular Distance (LTAD)), on the degree of quantitative tibial acceleration during the pivot shift test and rates of future ACL injury. METHODS: All patients who underwent primary ACL reconstruction from 2014 to 2019 by a senior orthopedic surgeon with available quantitative tibial acceleration data were retrospectively reviewed. All patients underwent a pivot shift examination under anesthesia with a triaxial accelerometer. Measurements of femoral and tibial bony morphology were performed by two fellowship-trained orthopedic surgeons using preoperative magnetic resonance imaging and lateral radiographs. RESULTS: Fifty-one patients were included at a mean follow-up of 4.4 years. The mean quantitative tibial acceleration during the pivot shift was 13.8 m/s2 (range: 4.9-52.0 m/s2). A larger Posterior Condylar Offset Ratio (r = 0.30, p = 0.045), smaller medial-to-lateral width of the medial tibial plateau (r = - 0.29, p = 0.041), lateral tibial plateau (r = - 0.28, p = 0.042), and lateral femoral condyle (r = - 0.29, p = 0.037), and a decreased LTAD (r = - 0.53, p < 0.001) significantly correlated with increased tibial acceleration during the pivot shift. Linear regression analysis demonstrated an increase in tibial acceleration of 1.24 m/s2 for every 1 mm decrease in LTAD. Nine patients (17.6%) sustained ipsilateral graft rupture and 10 patients (19.6%) sustained contralateral ACL rupture. No morphologic measurements were associated with rates of future ACL injury. CONCLUSION: Increased convexity and smaller bony morphology of the lateral femur and tibia were significantly associated with increased tibial acceleration during the pivot shift. Additionally, a measurement, termed the LTAD, was found to have the strongest association with increased tibial acceleration. Based on the results of this study, surgeons can utilize these measurements to preoperatively identify patients at risk of increased rotatory knee instability. LEVEL OF EVIDENCE: Level IV.

How Much Opioid Do Kids Actually Need? A Prospective Study of Analgesic Prescribing and Postdischarge Opioid Use Among Pediatric Patients With Operative Fractures.

BACKGROUND: Analgesic guidelines are lacking for most operative pediatric fractures, and little is known about postdischarge opioid use or pain control. We hypothesized that opioid/acetaminophen/non-steroidal anti-inflammatory drugs (NSAID) prescribing would vary, pain would be well controlled, and postdischarge opioid use would be low. METHODS: This prospective cohort study included nonpolytraumatized patients aged 17 years and below with operative fractures at a level 1 trauma center from August 1, 2019 to March 31, 2021. Supracondylar humerus fractures were excluded since they have been studied extensively. Information regarding injury/surgery/analgesics were collected. Discharged patients were called on postoperative days (POD) 1/3/5. Parents/guardians were asked about analgesic use and pain over the preceding 2 days. Complications, pain control, and opioid refills were recorded after first follow-up. RESULTS: All 100 eligible patients were included. Mean age was 10.1 years (range: 1.8 to 17.8 y). Common fracture types were humeral condyle/epicondyle (28%), radius/ulna (15%), and femoral shaft (13%). Opioids were prescribed to 95% of patients with mean 14 doses (range: 2 to 45). Acetaminophen/NSAIDs were prescribed to 74% and 60% of patients, respectively. Eleven patients were excluded from telephone follow-up (7 non-English speaking, 3 prohibitive social situations, 1 inpatient POD1 to 5). Telephone follow-up was completed for 87/89 eligible patients (98%). Mean pain scores declined from 3.7/10 POD1 to 2.4/10 POD5. Opioids were taken by 50% POD1, 20% POD5. Acetaminophen/NSAID was given before opioid 82% of the time. By POD5, mean total doses of opioid taken postdischarge was 2.3; mean proportion of prescribed opioid doses taken was 22%; and 97% of patients took ≤8 opioid doses postdischarge. Two patients were evaluated early due to poor pain control which improved with cast changes. Pain was well controlled or absent at follow-up in 97% of patients. CONCLUSIONS: Pain is consistently well controlled after operative pediatric fractures. Nearly all were prescribed opioids, while acetaminophen/NSAIDs were inconsistently prescribed and used. Opioid prescriptions are written for 4 to 5 times the amount needed. Prescribing ≤8 doses of opioid is adequate for acute pain through POD5 in 97% of patients. Poorly controlled pain should prompt early evaluation for possible complications. LEVEL OF EVIDENCE: Level II-prospective comparative study.

Proteolipid domains form in biomimetic and cardiac mitochondrial vesicles and are regulated by cardiolipin concentration but not monolyso-cardiolipin.

Cardiolipin (CL) is an anionic phospholipid mainly located in the inner mitochondrial membrane, where it helps regulate bioenergetics, membrane structure, and apoptosis. Localized, phase-segregated domains of CL are hypothesized to control mitochondrial inner membrane organization. However, the existence and underlying mechanisms regulating these mitochondrial domains are unclear. Here, we first isolated detergent-resistant cardiac mitochondrial membranes that have been reported to be CL-enriched domains. Experiments with different detergents yielded only nonspecific solubilization of mitochondrial phospholipids, suggesting that CL domains are not recoverable with detergents. Next, domain formation was investigated in biomimetic giant unilamellar vesicles (GUVs) and newly synthesized giant mitochondrial vesicles (GMVs) from mouse hearts. Confocal fluorescent imaging revealed that introduction of cytochrome c into membranes promotes macroscopic proteolipid domain formation associated with membrane morphological changes in both GUVs and GMVs. Domain organization was also investigated after lowering tetralinoleoyl-CL concentration and substitution with monolyso-CL, two common modifications observed in cardiac pathologies. Loss of tetralinoleoyl-CL decreased proteolipid domain formation in GUVs, because of a favorable Gibbs-free energy of lipid mixing, whereas addition of monolyso-CL had no effect on lipid mixing. Moreover, murine GMVs generated from cardiac acyl-CoA synthetase-1 knockouts, which have remodeled CL acyl chains, did not perturb proteolipid domains. Finally, lowering the tetralinoleoyl-CL content had a stronger influence on the oxidation status of cytochrome c than did incorporation of monolyso-CL. These results indicate that proteolipid domain formation in the cardiac mitochondrial inner membrane depends on tetralinoleoyl-CL concentration, driven by underlying lipid-mixing properties, but not the presence of monolyso-CL.

Prehospital Fluid Administration in Trauma Patients: A Survey of State Protocols.

OBJECTIVE: The optimal resuscitation approach during the initial treatment of hypotensive trauma patients remains unknown, but some clinical trials have observed a survival benefit from restricting fluid administration prior to definitive hemorrhage control. We sought to characterize emergency medical services (EMS) protocols for the administration of intravenous fluids in this setting. METHODS: Publicly accessible statewide EMS protocols for the treatment of hypotensive trauma patients were included and characterized by: 1) goal of fluid administration, 2) dosing strategy, 3) maximum dose, 4) type of fluid, and 5) specific protocols for head trauma, if present. RESULTS: Of the 27 states with a publicly available, statewide protocol, 21 have a numeric systolic blood pressure (SBP) target for resuscitation. Of these, 16 describe a goal of maintaining SBP ≥90 mmHg with or without additional goals, three specify a goal that is less than 90 mmHg, and two specify a goal ≥100 mHg. Dosing strategies also vary and include both standard bolus strategies (200 mL, 250 mL, 500 mL, and 1 L with repeat) as well as weight-based strategies (20 mL/kg). Nine states specify a maximum dose of 2 L without medical control. Fifteen protocols recommend the use of normal saline, 1 recommends the use of lactated Ringer's, and 11 recommend the use of either normal saline or lactated Ringer's. Nine states have distinct protocols for patients with head trauma, all of which indicate maintaining a higher SBP than for trauma patients without head trauma. CONCLUSION: State EMS protocols for fluid administration for hypotensive trauma patients vary in regard to SBP goal, fluid dose, and fluid type. Clinical trials to determine the optimal use of intravenous fluids for hypotensive trauma patients are needed to define the optimal approach.

Surgical Techniques in Primary ACL Reconstruction: Getting It Right the First Time.

The ideal anterior cruciate ligament reconstruction (ACLR) is an individualized anatomic approach aimed at restoring the native structure and function of the knee. Surgeons are tasked with difficult decisions during operative planning, including the optimal graft choice for the patient and appropriate anatomic tunnel placement. Special considerations should additionally be given for skeletally immature patients and those at high-risk for failure, including younger, active patients participating in pivoting sports. The purpose of this review is to provide an overview of the individualized approach to ACLR, including the necessary preoperative and operative considerations to optimize patient outcomes.

The Role of Osteotomy in Anterior Cruciate Ligament Reconstruction.

Coronal and sagittal plane knee malalignments have been shown to increase the forces on anterior cruciate ligament (ACL) grafts after ACL reconstruction (ACLR). Studies have shown the benefit of high tibial osteotomy to address coronal and sagittal imbalance in revision ACLR. The purpose of this article is to further describe the use of osteotomy by reviewing preoperative planning, indications, techniques, and outcomes of high tibial opening and closing wedge as well as anterior tibial closing wedge osteotomies in the setting of ACLR.

Revision Anterior Cruciate Ligament Reconstruction and Associated Procedures.

Failure of anterior cruciate ligament reconstruction (ACLR) is a common yet devastating complication due to inferior clinical outcomes associated with revision ACLR. Identifying the cause and associated risk factors for failure is the most important consideration during preoperative planning. Special attention to tunnel quality, concomitant injuries, and modifiable risk factors will help determine the optimal approach and staging for revision ACLR. Additional procedures including lateral extra-articular tenodesis and osteotomy may be considered for at-risk populations. The purpose of this review is to explore causes of ACLR failure, clinical indications and appropriate patient evaluation, and technical considerations when performing revision ACLR.

Lateral extra-articular tenodesis may be more cost-effective than independent anterolateral ligament reconstruction: A systematic review and economic analysis.

IMPORTANCE: Anterolateral augmentation during primary anterior cruciate ligament (ACL) reconstruction (ACLR) may lower rates of ACL graft failure. However, differences in costs between two techniques, lateral extra-articular tenodesis (LET) and anterolateral ligament reconstruction (ALLR), are unclear. OBJECTIVE: To perform a systematic review and subsequent cost-effectiveness analysis comparing LET versus ALLR in the setting of primary ACLR. The hypothesis was that LET is more cost-effective than ALLR. EVIDENCE REVIEW: A systematic review was conducted on studies in which patients underwent primary ACLR with a concomitant LET or ALLR with minimum 24 months follow-up published between January 2013 and July 2023. Primary outcomes included ACL graft failure rates and Knee Injury and Osteoarthritis Outcome Survey-Quality of Life (KOOS-QoL) subscale scores, which were used to determine health utilities measured by quality-adjusted life years (QALYs) gained. A decision tree model with one-way and two-way sensitivity analyses compared the cost of primary ACLR with a concomitant LET, independent autograft ALLR, or independent allograft ALLR. Costs were estimated using a combination of QALYs, institution prices, literature references, and a survey sent to 49 internationally recognized high-volume knee surgeons. FINDINGS: A total of 2505 knees undergoing primary ACLR with concomitant LET (n=1162) or ALLR (n=1343) were identified from 22 studies. There were 77 total ACL graft failures with comparable failure rates between patients receiving LET versus ALLR (2.9% vs. 3.2%, P=0.690). The average QALYs gained was slightly higher for those who received LET (0.77) compared to ALLR (0.75). Survey results revealed a 5 minute longer median self-reported operative time for ALLR (20 â€‹min) than LET (15 â€‹min). The estimated costs for LET, autograft ALLR, and allograft ALLR were $1,015, $1,295, and $3,068, respectively. CONCLUSIONS AND RELEVANCE: Anterolateral augmentation during primary ACLR with LET is more cost-effective than independent autograft and allograft ALLR given the lower costs and comparable clinical outcomes. Surgeons may utilize this information when determining the optimal approach to anterolateral augmentation during primary ACLR, although differences in preferred technique and health care systems may influence operative efficiency and material costs. LEVEL OF EVIDENCE: Systematic review; Level of evidence, IV.

Outcomes of bone-patellar tendon-bone autograft and quadriceps tendon autograft for ACL reconstruction in an all-female soccer player cohort with mean 4.8-year follow up.

OBJECTIVE: The purpose is to compare functional outcomes, return to soccer rates, and revision rates in an all-female soccer player cohort undergoing quadriceps tendon (QT) autograft ACLR versus bone-patellar tendon-bone (BPTB) autograft ACLR. METHODS: Female soccer players who sustained an ACL rupture and underwent primary anatomic, single-bundle ACLR with BPTB autograft or QT autograft were included. Demographic and surgical characteristics were collected. Outcomes of interest included Tegner score, International Knee Documentation Committee (IKDC) score, Marx score, return to soccer rates, and failure rates. RESULTS: Data on 23 patients undergoing BPTB autograft ACLR and 14 undergoing QT autograft ACLR was available. Average age was 18.7 years, and average follow up was 4.8 years. Overall, 76 â€‹% (28/37) returned to soccer and 5.4 â€‹% (2/37) underwent revision ACLR. No major significant differences were found in demographic or surgical characteristics. No differences were found in postoperative IKDC scores, preoperative, postoperative, or change from pre-to postoperative Marx activity scores, or pre-and postoperative Tegner scores between the groups. QT autograft ACLR patients had significantly less change in Tegner scores pre-to postoperatively compared to the BTPB autograft ACLR group (0.6 â€‹± â€‹1.2 versus 2.1 â€‹± â€‹1.8; p â€‹= â€‹0.02). Both groups had similar rates of return to soccer [78 â€‹% (18/23) BPTB autograft ACLR versus 71 â€‹% (10/14) QT autograft ACLR; p â€‹= â€‹0.64] and rates of revision (8.7 % (2/23) BPTB autograft ACLR; 0 % (0/14) QT autograft ACLR. CONCLUSION: Results of this study suggest that BPTB autograft ACLR and QT autograft ACLR produce comparable, successful functional and return to soccer outcomes in this all-female soccer player cohort study. Larger, prospective studies are needed to improve the strength of conclusions and provide more information on the optimal graft choice for female soccer players. Surgeons can use the results of this study to counsel female soccer players on expected outcomes after ACLR. LEVEL OF EVIDENCE: III.

Outcomes After Anterior Cruciate Ligament Reconstruction With Quadriceps Tendon in Adolescent Athletes at Mean Follow-up of 4 Years.

Background: Despite increasing use of quadriceps tendon (QT) autograft in anterior cruciate ligament (ACL) reconstruction (ACLR), limited data exist regarding its outcomes in high-risk adolescent athletes. Purpose: To (1) report the outcomes after QT ACLR in adolescent athletes and (2) identify patient-related and surgery-related factors that may influence failure rates after QT ACLR. Study Design: Case series; Level of evidence, 4. Methods: All patients aged 14 to 17 years who underwent primary anatomic, transphyseal, single-bundle QT ACLR between 2010 and 2021 with a minimum 2-year follow-up were included for analysis. Demographic and surgical data as well as preoperative International Knee Documentation Committee (IKDC) and Marx activity scores were collected retrospectively. All patients were also contacted to assess postoperative patient-reported outcomes (PROs), including IKDC and Marx activity scores, and return-to-sports (RTS) data. Outcomes of interest included rates of revision ACLR and ipsilateral complications, contralateral ACL tears, difference in pre- and postoperative PROs, and rates of RTS. Patient and surgical characteristics were compared between groups who required revision ACLR versus those who did not. Results: A total of 162 patients met inclusion criteria, of which 89 adolescent athletes (mean age 16.2 ± 1.1 years, 64% female) were included for analysis at mean follow-up of 4.0 years. Postoperative IKDC scores were significantly higher than preoperative scores (88.5 vs 37.5; P < .001), whereas Marx activity scores decreased postoperatively (14.3 vs 12.2; P = .011). Successful RTS occurred in 80% of patients at a mean time of 9.7 ± 6.9 months, and 85% of these patients returned to the same or higher level of sports. The most common reasons for failure to RTS included lack of time (n = 7, 70%) and fearing reinjury in the operative knee (n = 5, 50%). The overall revision ACLR rate was 10% (n = 9), and contralateral ACL tears occurred in 14% (n = 12) of patients. The overall ipsilateral knee reoperation rate was 22.5% (n = 20). No statistically significant differences in patient or surgical characteristics were observed between patients who underwent revision ACLR and those who did not. Conclusion: At a minimum 2-year follow-up after QT ACLR, adolescent athletes experienced significantly improved postoperative IKDC scores, high rates of RTS, and low rates of graft failure, despite a relatively high ipsilateral reoperation rate. Surgeons may utilize this information when identifying the optimal graft choice for adolescent athletes who have sustained an ACL injury and wish to return to high level of sporting activities.