Anterior Cruciate Ligament Rupture Research Articles

MMP3 single-nucleotide polymorphisms are associated with noncontact ACL injuries in competing high-level athletes.

Matrix metalloproteinases (MMPs) play an important role in matrix remodeling, as well as in ligament integrity. Anterior cruciate ligament (ACL) rupture is a severe and frequent knee injury in sports. The aim of this study was to investigate polymorphisms within the MMP3 gene with the predisposition for noncontact ACL rupture in the Croatian professional athletes. One hundred eighty-seven (95 with ACL rupture occurring through a noncontact mechanism and 92 asymptomatic controls) unrelated Caucasians were recruited between 2016 and 2017. All participants were genotyped for three single-nucleotide polymorphisms (SNP) within the MMP3 gene: rs591058 C/T, rs650108 A/G, and rs679620 G/A using the pyrosequencing method. For all three investigated SNPs, genotype frequencies have significantly differed between cases and controls. The MMP3 rs591058 TT (p = 0.0012, odds ratio [OR] = 38.541, 95% confidence interval [CI] = 1.7024-8.7254), rs650108 GG (p = 0.0051, OR = 23.338, 95% CI = 1.2899-4.2226) and rs679620 AA (p = 0.0030, OR = 34.750, 95% CI = 1.5266-7.9101) genotypes, as well as haplotype variant T-G-A (p = 0.0104, OR = 1.71, 95% CI = 1.13-2.59) were significantly overrepresented in cases compared to controls. These results support association between functional variants within the MMP3 gene and the risk of ACL rupture. Still, further research is needed to corroborate these results in a larger population.

Characterization and Prevalence of Pediatric Ramp Lesions Associated with Anterior Cruciate Ligament Tears.

Background: Ramp lesions correspond to posterior meniscocapsular tears of the medial meniscus and are common with anterior cruciate ligament (ACL) tears. They cannot be recognized easily on preoperative magnetic resonance imaging (MRI) scans and are difficult to visualize even using standard arthroscopic approaches. We aim to (1) characterize and evaluate the prevalence of ramp lesions in pediatric patients at a major tertiary children's hospital, providing important insights into demographics, diagnosis, treatment, and functional disability and (2) evaluate the efficacy of MRI in its diagnosis.
 Materials and Methods: We retrospectively reviewed patients under 21 years old undergoing posterior medial meniscal injuries and anterior cruciate ligament ruptures with arthroscopic examination and positive ramp lesions from 2018 to 2021. Patient demographics (including gender and age), initial presentation, physical examination findings, mechanism of injury, pre-operative radiologic findings, and treatment were collected and reviewed via electronic medical record. Exclusion criteria included patients over 18 years old, patients, that did not have an MRI, and patients that were not treated surgically.
 Results: There were 117 patients that met the inclusion criteria out of 690 patients. The mean age at diagnosis was 15.6±1.6 years and the mean BMI was 26.7±6.4. 83% of injuries occurred secondary to sporting activities. Ramp lesions were only detected on preoperative MRI in 63% of cases, suspected in 3%, and not detected in 33%. The sensitivity of the MRI was 63%.
 Conclusions: Ramp lesions were found in 117/690 (16.9%) of patients undergoing ACL reconstruction. MRI had a low sensitivity rate of 63%. During ACL reconstruction, a careful review of the posteromedial compartment is important to recognize less obvious trauma. Lack of treatment may lead to continued instability and risk of complications in these patients.

Effectiveness of anterior cruciate ligament reconstruction with personalized femoral locator based on apex of deep cartilage

To investigate the effectiveness of anterior cruciate ligament (ACL) reconstruction assisted by personalized femoral locator based on the apex of deep cartilage (ADC) combined with patient imaging data. Between January 2021 and January 2022, a total of 40 patients with primary ACL rupture were selected and randomly divided into study group (ACL reconstruction assisted by personalized femoral locator based on ADC) and control group (ACL reconstruction assisted by intraoperative fluoroscopy and traditional femoral locator), with 20 cases in each group. There was no significant difference in gender, age, body mass index, affected side, cause of injury, and preoperative International Knee Documentation Committee (IKDC) score, Lyshlom score, and Tegner score between the two groups ( P>0.05). IKDC score, Lyshlom score, and Tegner score were used to evaluate the functional recovery of the affected knee before operation and at 3, 6, and 12 months after operation. CT scan and three-dimensional reconstruction were performed before and after operation to measure the horizontal distance from ADC to the anterior cartilage margin (L) and the horizontal distance from ADC to the center of the femoral canal (I), and the anteroposterior position of the bone canal (R) was calculated by I/L; the distance from the center to the distal cartilage margin (D) was measured on the two-dimensional cross section; the R value and D value were compared between the two groups. The operation time of the study group was significantly less than that of the control group [ MD=-6.90 (-8.78, -5.03), P<0.001]. The incisions of the two groups healed by first intention, and no complication such as intra-articular infection, nerve injury, and deep vein thrombosis of lower limbs occurred. There was no significant difference in the R value and D value between the preoperative simulated positioning and the actual intraoperative positioning in the study group [ MD=0.52 (-2.85, 3.88), P=0.758; MD=0.36 (-0.39, 1.11), P=0.351]. There was no significant difference in the actual intraoperative positioning R value and D value between the study group and the control group [ MD=1.01 (-2.57, 4.58), P=0.573; MD=0.24 (-0.34, 0.82), P=0.411]. The patients in both groups were followed up 12-13 months (mean, 12.4 months). The IKDC score, Lysholm score, and Tegner score of the two groups increased gradually with time, and there were significant differences between pre- and post-operation ( P<0.05). There was no significant difference in the scores between the two groups at each time point after operation ( P>0.05). The personalized femoral locator based on ADC can accurately assist the femoral tunnel positioning in ACL reconstruction, which can shorten the operation time when compared with traditional surgical methods, and achieve satisfactory early effectiveness.

Effects of a proprioceptive focal stimulation (Equistasi®) on reducing the biomechanical risk factors associated with ACL injury in female footballers.

Football presents a high rate of lower limb injuries and high incidence of Anterior Cruciate Ligament (ACL) rupture, especially in women. Due to this there is the need to optimize current prevention programs. This study aims to verify the possibility to reduce the biomechanical risk factors associated with ACL injury, through the application of proprioceptive stimulation by means of the Equistasi® device. Ten elite female footballers were enrolled and received the device for 4 weeks (5 days/week, 1h/day). Athletes were assessed directly on-field at four time points: T0 and T1 (evaluation without and with the device), T2 (after 2 weeks), T4 (after 4 weeks) while performing two different tasks: Romberg Test, and four sidestep cutting maneuvers bilaterally. Seven video cameras synchronized with a plantar pressure system were used, thirty double colored tapes were applied on anatomical landmarks, and three dimensional coordinates reconstructed. Vertical ground reaction forces and center of pressure data were extracted from the plantar pressure insoles. Hip, knee, and ankle flexion-extension angles and moments were computed as well as abd-adduction joint torques. From the Romberg Test both center of pressure descriptive variables and frequency analysis parameters were extracted. Each variable was compared among the different time frames, T1, T2 and T4, through Friedman Test for non-parametric repeated measures (p<0.05); Wilcoxon Signed Rank Test was used for comparing variables between T0 and T1 (p<0.05) and across the different time frames as follows: T1-T2, T2-T4 and T1-T4. Statistically significant differences in both posturographic and biomechanical variables between the assessment at T0 and T1 were detected. Reduced hip and knee abduction torques were revealed in association with reduced both ground reaction forces and ankle dorsiflexion torque from T1 up to T4. The proprioceptive stimuli showed to have the potential to improve cutting biomechanics mainly with respect to the ligament and quadriceps dominance theories. Results of the present study, even if preliminary and on a small sample size, could be considered promising towards the inclusion of proprioceptive training in injury prevention programs.

Markers of Pain in 3 Different Murine Models of Posttraumatic Osteoarthritis: A Comparison Using Gait Analysis, Imaging, Histology, and Gene Expression

Background: Animal models play an important role in studying posttraumatic osteoarthritis (PTOA) disease progression. Different models exist, such as destabilization of the medial meniscus (DMM), anterior cruciate ligament (ACL) surgical transection (ACLs), and noninvasive ACL rupture. Purpose: To study the effects of PTOA on nociception in 3 different murine models and to relate these findings to macroscopic and microscopic changes in joint tissues. Study Design: Controlled laboratory study. Methods: A total of 42 male C57BL/6 mice, 12 weeks old, were randomly assigned to 4 groups: intact control (n = 10), DMM (n = 10), ACLs (n = 11), and closed ACL rupture (ACLc; n = 11) groups. Gait analysis was performed on 5 mice from the DMM group and 6 mice from ACLs and ACLc groups at 0, 1, 2, 4, 8, and 12 weeks after injury. At the 12-week time point, all mice underwent radiographs and then either micro–computed tomography imaging followed by histology and immunohistochemistry or gene expression analysis of the dorsal root ganglion and tibialis anterior muscle. Results: The peripheral and central pain markers were expressed at significantly higher levels in the synovium of both ACL injury groups when compared with the DMM group. Muscle atrophy genes were significantly upregulated in the ACL injury groups. Pain-related gait behavior started at 4 weeks for the ACL rupture groups and at 12 weeks for the DMM group. High-resolution radiographic imaging and histology demonstrated divergent changes in bone microstructure between the ACLs and DMM groups, suggesting different mechanical loading environments in these models. Conclusion: The principal finding of this study is the presence of markers of nociception at both the gene and the protein levels, with earlier expression in the ACL injury groups when compared with the DMM group. The second finding of this study is that the noninvasive ACL rupture model demonstrated changes comparable with those of the commonly used surgical ACL transection model, supporting use of this clinically realistic model in future studies of PTOA. Clinical Relevance: Quantitative clinical outcomes (imaging, pain scale, gait changes) related to osteoarthritis severity in an animal study, allowing for better understanding of clinical outcomes of osteoarthritis progression after ACL injuries in humans.

Anterior Cruciate Ligament Reconstruction and Accelerated Rehabilitation with InternalBrace™ Augmentation in a Professional Footballer.

Interest in anterior cruciate ligament (ACL) repair has been increasing as an alternative to traditional reconstructive techniques and encouraging results have been demonstrated using internal bracing with suture tape augmentation (FiberTape®, Arthrex, Naples, Florida). ACL repair is challenging if the rupture is mid-substance or distal. We describe the case of a hybrid ACL reconstruction with internal brace augmentation. This retrospective case report documents the rehabilitation process of a 31-year-old professional footballer who had an isolated ACL rupture. The patient underwent a hybrid ACL reconstruction with bone-patellar tendon-bone autograft and suture tape augmentation 10 days after his injury. A task-based rehabilitation programme defined by six progressive phases relevant to performance-based outcome measures was undertaken. Each phase had clear, functional, progressive goals incorporating exercises to improve mobility, neuromuscular control, strength, and a progressive return to running and sport-specific movements. Using the rehabilitation framework outlined, this player produced excellent results in all objective criteria postoperatively and was able to return to unrestricted full team training in under five months (146 days) following surgery. This case presentation demonstrates the safe and accelerated return to professional football following ACL reconstruction augmented with internal bracing. The player was able to meet all criteria-based aspects of return to play.

Anterior Cruciate Ligament Ruptured Concomitant Meniscus Discoid in Young Patient: A Rare Case Report

Background: Abnormalities of the human meniscus, including discoid meniscus, double-layered meniscus, and ring-shaped meniscus, have been reported. The prevalence of discoid meniscus is extremely rare, with an incidence of 0.9%－2.4% in the Asian population. Traditionally, discoid meniscus concomitant anterior cruciate ligament (ACL) ruptures are extremely rare cases. The aim of this study is to discuss a rare case to provide diagnosis and management properly by using arthroscopy.Case Presentation: A 21-year-old male Balinese, complained of pain in his right knee after fast walking for two months and an unstable knee in the past 1 year ago. On physical examination, the range of motion was limited due to the pain for flexion of more than 90°. Special tests such as Lachman test positive, and Anterior drawer test positive. The patient had medial joint line tenderness, and a McMurray test elicited pain on the medial joint line. Meanwhile, an MRI examination of the right knee showed a discoid medial meniscus with a horizontal cleavage tear and a discoid lateral meniscus with an incomplete tear. We performed a partial meniscectomy of the incomplete discoid medial meniscus and resection of the pathologic medial patellar plica. We performed surgical reconstruction of the ACL ruptured after the meniscus was repaired.Results: We presented a 21-year-old male with discoid meniscus concomitant ACL rupture to his right knee. After the patient was performed with partial meniscectomy of the incomplete discoid medial meniscus and resection of pathologic medial patellar plica following surgical reconstruction of the ACL ruptured. The patient had no limitation of motion or pain 1 year after the operation and he had no complaints and was satisfied with the result by radiograph.Conclusion: We concluded that This rare case of medial discoid meniscus concomitant with the ACL rupture must be reconstructed. The treatment of discoid meniscus should consider its tear pattern and whether it is symptomatic. With the development of arthroscopic techniques, the treatment of discoid meniscus has gradually changed from total meniscectomy or partial meniscectomy.Keywords: anterior cruciate ligament, meniscus, discoid, knee, arthroscopy.Correspondence: I Gusti Ngurah Wien Aryana. Department of Orthopaedic &amp; Traumatology, General Central Hospital of I.G.N.G Ngoerah Central Hospital/ Faculty of Medicine, Udayana University, Bali, Indonesia. Email: wienaryanaortho@gmail.com. Mobile: +62811-385-263.Indonesian Journal of Medicine (2023), 08(03): 317-324https://doi.org/10.26911/theijmed.2023.08.03.09

Evidence of Bacterial Metabolism in Synovial Fluid of Patients With Graft Failure After Anterior Cruciate Ligament Reconstruction: A Microbiological Comparison of Primary Anterior Cruciate Ligament and Hamstring Tendon Autograft Ruptures

To investigate whether the bacterial presence in a primary ruptured native anterior cruciate ligament (ACL) differs from that in a ruptured hamstrings ACL autograft and whether low-grade infections cumulatively can be detected in the case of graft failure. In a retrospective case-control study with prospectively collected data, synovial fluid aspirates and tissue samples of failed ACL grafts were examined for evidence of bacterial colonization and compared to samples of the native ACL in primary ACL reconstruction (ACLR) using microbiological culture, 16S rRNA-PCR and histopathological examination. Furthermore, synovial fluid aspiration was investigated for possible future biomarkers for a low-grade infection. A total of 112 consecutive patients undergoing primary ACLR without history of previous surgeries to the affected knee (n= 59) and revision ACLR after reconstruction with a hamstring tendon autograft (n= 53) were recruited from one center. No patient had a history or showed clinical signs of infection. A total of 389 samples were analyzed by culture. Bacteria were detected in 9.4% of patients with a graft rupture (n= 5/53) compared to 3.4% of patients with a primary ACL rupture (n= 2/59) showing no statistical difference (P= .192). One patient with a "true" low-grade infection was found in our study population, resulting in a prevalence of 1.9% (1/53) in the graft group. The percentage of polymorphonuclear leukocytes (PMN%) as a highly sensitive marker for joint infections was significantly higher in aspirated synovial fluid of graft ruptures (27% ± 3% vs 20% ± 4%; P= .032), as well as glucose levels were significantly lower (83 mg/dL ± 2 mg/dL vs 88 mg/dL ± 2 mg/dL; P= .042). Synovial fluid obtained before revision ACLR showed a higher percentage of polymorphonuclear leukocytes and lower glucose levels compared with primary ACLR, suggesting bacterial metabolism and demonstrating that the intra-articular milieu changes significantly after ACLR. Tissue samples of ACL grafts revealed a low-grade infection in one case, although overall cultivable bacterial presence did not differ significantly when compared to samples of a native ACL. Level III, retrospective case-control study.

Collagen Gene Variants and Anterior Cruciate Ligament Rupture in Italian Athletes: A Preliminary Report.

Several studies have investigated the role of genetics in anterior cruciate ligament (ACL) rupture, often returning conflicting results. The present pilot study aimed to analyze the association between six Single Nucleotide Polymorphisms (SNPs) (rs1800012; rs12722; rs13946; rs240736; rs970547; and rs4870723, located on the COL1A1, COL5A1, COL12A1, and COL14A1 genes), and ACL rupture, among Italian athletes. A hypothesis-driven association study was conducted. In total, 181 male and female athletes (n = 86 injured; n = 96 non-injured) were genotyped for the prioritized variants. All polymorphisms were genotyped using PCR RFLP, with the only exception being the rs1800012 on the COL1A1 gene, which was detected using MTPA PCR. The allele frequency distribution fell within the worldwide range. Despite the evident population variability, no selective pressure signals were recorded using PBS analysis. No significant difference was detected between the cases and controls for any of the SNPs (rs1800012; rs13946; rs240736; rs970547, and rs4870723) included in the analyses (p > 0.008, Bonferroni-adjusted for multiple comparisons). Moreover, no significant differences were found when males and females were assessed separately. Further investigations based on a larger sample size are needed, in order to draw solid conclusions for the influence between collagen genes and ACL rupture.

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

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. 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. Fifty-one patients were included at a mean follow-up of 4.4years. The mean quantitative tibial acceleration during the pivot shift was 13.8m/s2 (range: 4.9-52.0m/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 1.24m/s2 for every 1mm 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. 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 IV.

Paper 25: The Impact of Posterior Tibial Slope on Meniscal Injury in Acute ACL Ruptures: A Large, Retrospective Registry Study

Objectives: Increased posterior tibial slope has previously been associated with an elevated risk of anterior cruciate ligament (ACL) rupture. Recent studies have suggested there may be a relationship between posterior slope and meniscal tears in ACL ruptures, however, these studies have either included chronic ACL injuries, revision ACL reconstructions or an overall low number of study participants. The goal of this study is to leverage a large ACL registry to assess the impact of posterior tibial slope on meniscal tears in acute ACL ruptures. Methods: A large, single-institution knee registry was consulted to identify all patients between the age of 18 and 45 who underwent primary ACL reconstruction between Jan 2019 and July 2022 for acute, noncontact ACL rupture, defined as undergoing surgery within 90 days of injury. Patients with pre-existing meniscal pathology, chronic ACL reconstructions, revisions, multi-ligament knee injuries and nonoperatively managed ACL injuries were excluded. Preoperative MRIs were used to measure lateral and medial posterior tibial slope for all patients. Meniscal injury seen in-situ during arthroscopy was recorded based on operative reports. Demographics data, including age, sex, and body mass index, was also recorded. Independent cohorts were created based on the presence or absence of any meniscal injury. Two-tailed student’s t tests were used to compare average medial and lateral posterior tibial slopes between these groups. Separate analyses were also performed to assess the impact of posterior slope on medial and lateral meniscus tears independently. Multiple logistic regression was carried out to determine risk factors for meniscal injury in this population. Results: 1059 patients ultimately met inclusion criteria. The average age was 29.5 and there were 532 (50%) women. There were 253 (24%) patients with isolated lateral meniscus tears, 152 (14%) patients with isolated medial meniscus tears and 93 (9%) patients with both medial and lateral tears. The average lateral and medial posterior tibial slopes were 5.54 (-4.2 to 13.4) and 5.67 (0 to 15.7), respectively. Increased lateral tibial slope was associated with a statistically significant increase in rate of any meniscal tear (p=.0022). Lateral slope was also associated with a higher rate of lateral meniscal tears, specifically (p=.0009). Multiple logistic regression identified elevated BMI and male sex as independent risk factors for meniscal injury in this population. Conclusions: Increased lateral posterior tibial slope is associated with a higher rate of meniscus injury in acute ACL ruptures and should be considered when devising treatment algorithms for patients in this population. [Table: see text][Table: see text][Table: see text][Table: see text]

Paper 39: A Survival Analysis of ACL Graft and Contralateral ACL Ruptures in Patients Under 18 Years

Objectives: Although high rates of graft and contralateral anterior cruciate ligament (ACL) ruptures have been reported in younger patients after ACL reconstruction, recent evidence suggests that previously reported crude event rates underestimate the actual event risk. Therefore, the aim of this study was to report rates of graft and contralateral ACL rupture after ACL reconstruction in a large series of younger patients using survival analysis. Methods: A consecutive series of 400 patients who were under 18 years at the time of primary ACL reconstruction were identified from a single surgeon database over a 12-year period ending January 2018. Patients with a prior contralateral ACL rupture (n=8) or bilateral ACL ruptures (n=2) were excluded as were two patients who died within 6 months of surgery, leaving 388 (203M, 185F) in the final dataset. Bespoke survey data and clinic follow-up data were used to record graft rupture and contralateral ACL rupture events. Rates of graft and contralateral ACL rupture were calculated with Kaplan-Meier survival analysis. Log rank tests were used to compare survival functions between males and females. Results: The cumulative rates of graft rupture via survival analysis were 11% at 2 years, 16% at 4 years and 28% at 8 years. For contralateral ACL injury the cumulative rates were 7% at 2 years, 17% at 4 years and 49% at 8 years. Males had significantly greater rates of graft rupture than females although this was more prominent at 4 years (22% vs 9%) than at 8 years (31% vs 23%) after surgery (figure 1). Contralateral ACL rupture survival functions were not significantly different between male and female patients, although rates were higher in females until 5 years after which males had a notable increase in contralateral ACL ruptures with a cumulate rate of 63% at 8 years compared to 35% for females (figure2). Conclusions: The current study is one of the largest consecutive series of younger patients with one of the longest follow-up periods that reports a high risk for a second ACL injury. Over time, the cumulative risk for contralateral ACL rupture was higher than for graft rupture. This contradicts previous work that had shorter follow-up times. In males, the risk for contralateral ACL rupture substantially increased after 5 years. Understanding the postoperative time course for second ACL injury in young patients is important so that factors which contribute to this increased risk can be better understood and such injuries prevented.

Rupture of anterior cruciate ligaments and the Lever Test in diagnosis: a critical review

Anterior Cruciate Ligament (ACL) rupture is known to be one of the most common musculoskeletal injuries in active individuals especially athletes. Approximately 200,000 ACL injuries occur every year, of which 100,000 require surgery. Once ruptured, it becomes very difficult to regain its previous function and it does not have the capacity to heal on its own. It is thus very important to diagnose an ACL rupture as early as possible. Clinicians need to perform a test which has a high sensitivity to rule out a negative test and specificity in order to rule in a positive test in the diagnosis. In this review four different tests (Lever Sign Test, Lachman Test, Anterior Drawer Test and Pivot Shift Test) are put to comparison and it is aimed to find the accuracy of the Lever Sign Test in diagnosing ruptured ACL as a diagnostic tool.

Poster 325: Untreated Ruptures of the Anterior Cruciate Ligament: a 54 Year Follow-Up Study

Poster 325: Untreated Ruptures of the Anterior Cruciate Ligament: a 54 Year Follow-Up Study

Poster 298: Establishment of a Novel Distance and Angle and Determining Their Relationship with the ACL

Poster 298: Establishment of a Novel Distance and Angle and Determining Their Relationship with the ACL

The impact of the menstrual cycle on orthopaedic sports injuries in female athletes.

There is a disparity in sport-related injuries between sexes, with females sustaining non-contact musculoskeletal injuries at a higher rate. Anterior cruciate ligament ruptures are between two and eight times more common than in males, and females also have a higher incidence of ankle sprains, patellofemoral pain, and bone stress injuries. The sequelae of such injuries can be devastating to an athlete, resulting in time out of sport, surgery, and the early onset of osteoarthritis. It is important to identify the causes of this disparity and introduce prevention programmes to reduce the incidence of these injuries. A natural difference reflects the effect of reproductive hormones in females, which have receptors in certain musculoskeletal tissues. Relaxin increases ligamentous laxity. Oestrogen decreases the synthesis of collagen and progesterone does the opposite. Insufficient diet and intensive training can lead to menstrual irregularities, which are common in female athletes and result in injury, whereas oral contraception may have a protective effect against certain injuries. It is important for coaches, physiotherapists, nutritionists, doctors, and athletes to be aware of these issues and to implement preventive measures. This annotation explores the relationship between the menstrual cycle and orthopaedic sports injuries in pre-menopausal females, and proposes recommendations to mitigate the risk of sustaining these injuries.

Paper 38: Addition of a Lateral Extra-articular Tenodesis is Associated with Lower Quadriceps Tendon Autograft MRI Signal Intensity Two Years Following Anterior Cruciate Ligament Reconstruction in Skeletally Immature Adolescents

Objectives: In recent studies, quadriceps tendon autograft (QTA) has been shown to yield promising results in the treatment of anterior cruciate ligament (ACL) ruptures in pediatric and adolescent patients. Additionally, lateral extra-articular tenodesis (LET) has been found to reduce the risk of ACL re-tear in high-risk patients when performed concomitantly with ACL reconstruction (ACLR). The purpose of this study was to evaluate graft maturity two years after ACLR by comparing magnetic resonance imaging (MRI) signal intensity ratio (SIR) of QTA in patients that underwent a primary ACL reconstruction with a concomitant LET versus patients without a concomitant LET. Methods: After institutional review board approval, operative records of all pediatric patients ≤ 18 years old who underwent an ACLR from June 2015 to December 2021 were retrospectively reviewed. MRIs were ordered for this age cohort of patients for clinical growth plate surveillance. Patients were included if they underwent an ACLR using a QTA and had open distal femoral and proximal tibial physes. MRIs were excluded if they were external or were ordered due to a new injury. The final cohort included 28 patients: 13 without a LET (ACLR only) and 15 with a LET (ACLR+LET). Signal intensity ratio (SIR) was measured on sagittal MRI by averaging the signal at three regions of interest along the ACL graft and dividing by the signal of the insertion of the posterior cruciate ligament. Statistical analysis was performed to evaluate for differences in SIR values at 6 months, 1 year, and 2 years post-operatively in skeletally immature patients undergoing ACLR alone versus ACLR with LET. Results: A total of 43 patients had an MRI at a two-year follow-up, 28 of whom were included in the study. The mean age of the complete cohort was 12.63±3.62 years (ACLR+LET: 13.96±0.91 years vs. ACLR only: 13.51±1.19 years). There were no significant differences in SIR between groups on the 6-month MRI or the 12-month MRI. However, the average SIR of the ACLR+LET group was significantly lower than the average SIR of the ACLR-only group at the two-year post-operative time point (1.398 vs. 1.916, respectively, p=0.046). Conclusions: QTA MRI signal intensity is lower two years after surgery in patients that underwent ACLR with a LET versus ACLR alone. Lower MRI signal intensity correlates with increased graft maturity and structural integrity. These findings suggest improved graft maturation, remodeling, and structural integrity with the addition of a LET to an ACLR with QTA in skeletally immature patients. [Table: see text]

Nonoperative Treatment for Traumatic Partial Graft Rupture After Anterior Cruciate Ligament Reconstruction: A 2-Year Follow-up Study.

There are no studies on the nonoperative treatment of traumatic partial anterior cruciate ligament (ACL) graft rupture. The purpose of this study was to compare the clinical and radiological outcomes and failure rates between nonoperative treatment and revision ACL reconstruction for traumatic partial ACL graft rupture. We hypothesized that the outcomes and failure rates would be comparable and that nonoperative treatment of traumatic partial ACL graft rupture can produce satisfactory outcomes. Cohort study; Level of evidence, 3. We retrospectively evaluated 2114 patients treated for isolated ACL rupture between January 2000 and June 2020. Patients with traumatic partial graft rupture after ACL reconstruction with minimum 2-year follow-up data were included. Patients who met all the following conditions were candidates for nonoperative treatment: (1) Lachman or pivot-shift grade 0 or 1 at 6 months after ACL reconstruction, (2) ACL graft with low to intermediate signal intensity on 1-year postoperative magnetic resonance imaging (MRI), and (3) MRI after reinjury showing definite evidence of trauma, some fibers remaining in continuity of the ACL graft, and no anterior tibial subluxation in the sagittal plane. The patients were divided into 2 groups according to treatment method: nonoperative treatment (group A) and revision ACL reconstruction (group B). Clinical scores, laxity test results, radiological outcomes, and graft failures were compared between the groups. In total, 47 patients had traumatic partial graft rupture (group A, n = 10; group B, n = 37). There were no significant differences between the 2 groups in terms of clinical scores, laxity tests, radiological outcomes, or graft failure. The clinical and radiological outcomes of nonoperative treatment of traumatic partial graft rupture after ACL reconstruction were comparable with those of revision ACL reconstruction. Nonoperative treatment of traumatic partial ACL graft rupture can produce satisfactory outcomes in selected patients.

Poster 272: The Significance Of Posterior Tibial Slope And Rate Of Concomitant Pathology In Pediatric Tibia Spine Avulsion And Anterior Cruciate Ligament Injuries

Objectives: Fractures of the tibial spine (TSF) occur as a result of an anterior cruciate ligament (ACL) avulsion fracture from the proximal tibia. Both TSF and ACL injuries are associated with concomitant intraarticular pathology seen on Magnetic Resonance Imaging (MRI) and intraoperatively. In addition, posterior tibial slope (PTS) has been identified as a potential risk factor for ACL injury. The purpose of this study is to describe concomitant injuries seen on MRI and at time of surgery for TSF and ACL patients, and to characterize posterior tibial slope in patients who sustain these injuries. Our hypothesis is that ACL and TSF injuries have similar rates of meniscal injury, and that posterior tibial slope is increased in patients with TSF and ACL injuries compared to matched controls. Methods: Utilizing an institutional review board approved retrospective study, we identified patients under 18 years of age who underwent arthroscopic management of a TSF from December 31st 2008 to December 31st 2021. Exclusion criteria were patients with a concomitant lower extremity fracture or posterior cruciate ligament injuries, poor imaging quality, and incomplete medical records. TSF patients were compared to an age and gender matched cohort of patients who underwent surgery for a mid- substance ACL rupture, and a similar control group. We evaluated concomitant injuries based on radiology and operative reports and measured PTS on radiographs as well as medial (MTS) and lateral (LTS) posterior slope on MRI for all groups. We compared tibial slope amongst the groups using a one- way analysis of variance test, and the Fisher’s exact test was used to compare concomitant injuries between the ACL and TSF groups. Results: 85 TSF patients met inclusion criteria, of which 44 had an MRI. There were 41 patients in the ACL group and 44 in the control group. The average age was 11.8 years. Concomitant injuries were identified on MRI in 59.1% of TSF and 51.2% of ACL patients, and intraoperatively in 36.5% of TSF and 37% of ACL patients. The most common concomitant injury was lateral meniscus tears. There was no significant differnce between the TSF and ACL groups in terms of lateral meniscus tears seen on MRI (29.5% TSF vs 31.7 ACL, p=1.0) and seen on arthroscopy (18.2% TSF vs 31.7% ACL, p=0.21). Similarly there were no significant differences between the TSF and ACL group in terms of medial meniscus tears seen on MRI (13.6% vs 17.1%, p = 0.77) and on arthroscopy (9% vs 5%, p=0.19). There was a significant difference between groups when comparing the pivot-shift bone bruise pattern seen on MRI (63.6% TSF vs 90.2% ACL, P= &lt;0.01). There was significantly increased radiographic PTS in the TSF and ACL groups (Radiographs 8.7°+/-3.0° TSF vs 9.5°+/-3.3° ACL vs 6.6°+/-2.3° Control, p= &lt;0.01). This was also seen in the MTS mesured on MRI (MTS 5.3°+/-3.1° TSF vs 4.9°+/-2.7° ACL vs 3.7°+/-2.3° Control p= 0.02). There was no significant difference in LTS between TSF and Controls, but there was between ACL and Controls (LTS 4.1°+/-2.8° TSF vs 6.8°+/- 3.9°ACL vs 4.3°+/- 2.3° Control, p=&lt;0.01). Conclusions: This study is the first to depict tibial slope and bone contusion patterns seen in tibial spine injuries, as well as compare rates of meniscal injury and tibial slope between ACL and control patients. Posterior tibial slope is significantly increased in patients who sustain a TSF or ACL injury, suggesting that it may be a risk factor for injury. Similar rates of concomitant meniscal pathology are seen in both TSF and ACL injured patients, which may reflect similar mechanisms of injury. This also highlights that care must be taken to evaluate for additional pathology when treating TSF and ACL injuries. Future study is needed to determine the role, if any, that tibial slope plays in tibial spine fractures as well as to determine if intraarticular pathology identified on MRI influences longer term patient outcomes.

The Hybrid Transtibial Technique Using the LARS Device in Primary Anterior Cruciate Ligament Reconstruction

Background: The recently published hybrid transtibial technique (HTT) using the Pathfinder Guide with a flexible transtibial technique (TT) guide wire may represent a beneficial combination of both the anteromedial portal and TT technique. The HTT has been described as especially suitable for anterior cruciate ligament (ACL) reconstruction in adolescents or ACL revision. However, we also found that the HTT worked for primary ACL reconstruction in adults also using the Ligament Advanced Reinforcement System (LARS). Indications: Acute ACL rupture in active patients who are eager to return to sports quickly. Technique Description: The HTT combined with the conventional LARS reconstruction procedure improves the placement of the femoral tunnel, which involves a guiding vessel clamp through the anteromedial portal combined with a 2.0 mm Kirschner wire via the tibial tunnel. Finally, we used a metal screw for fixation of the ligament. Results: The patient experienced satisfactory reconstruction of his ACL and regained active range of motion in 1 month and a full return to sports in 6 months. Discussion/Conclusion: The HTT using the LARS for primary ACL reconstruction is easy, safe, and reproducible. This combined technique has not yet been published and it may provide good functional results that allow patients to recover quickly and return to sports as soon as possible. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.