Anterior cruciate ligament primary repair revision rates are increased in skeletally mature patients under the age of 21 compared to reconstruction, while adults (>21 years) show no significant difference: A systematic review and meta-analysis.

PURPOSE: To evaluate the impact of age as a risk factor on the revision rates of anterior cruciate ligament (ACL) primary repair (ACLPR), dynamic intraligamentary stabilization (DIS) and bridge-enhanced ACL restoration (BEAR) compared to ACL reconstruction (ACLR). METHODS: A systematic literature search was performed for comparative studies comparing outcomes for ACLPR, DIS or BEAR to ACLR. A random-effects meta-analysis was performed to assess nondifferentiated and age-differentiated (skeletally mature patients ≤21 and >21 years) ACL revision and reoperation risk, as well as results for subjective outcomes. Methodological study quality was assessed using the Risk of Bias Tool 2.0c and Methodological Index for Nonrandomized Studies tools. RESULTS: A total of 12 studies (n = 1277) were included. ACLR demonstrated a lower nonage-stratified revision risk at 2 years versus ACLPR, DIS and BEAR, but a similar revision risk at 5 years when compared to DIS. However, an age-stratified analysis demonstrated a significantly increased ACLPR revision risk as compared to ACLR in skeletally mature patients ≤21 years of age (risk ratios [RR], 6.33; 95% confidence interval [CI], 1.18-33.87, p = 0.03), while adults (>21 years) showed no significant difference between groups (RR, 1.48; 95% CI, 0.25-8.91, n.s.). Furthermore, DIS reoperation rates were significantly higher than respective ACLR rates (RR, 2.22; 95% CI, 1.35-3.65, p = 0.002), whereas BEAR (RR, 1.07; 95% CI, 0.41-2.75, n.s.) and ACLPR (RR, 0.81; 95% CI, 0.21-3.09, n.s.) showed no differences. IKDC scores were equivalent for all techniques. However, ACLPR exhibited significantly better FJS (mean difference, 11.93; 95% CI, 6.36-17.51, p < 0.0001) and Knee injury and Osteoarthritis Outcome Score Symptoms (mean difference, 3.01; 95% CI, 0.42-5.60, p = 0.02), along with a lower Tegner activity reduction. CONCLUSIONS: ACLPR in skeletally mature patients ≤21 years of age is associated with up to a six-fold risk increase for ACL revision surgery compared to ACLR; however, adults (>21 years) present no significant difference. Based on the current data, age emerges as a crucial risk factor and should be considered when deciding on the appropriate treatment option in proximal ACL tears. LEVEL OF EVIDENCE: Level III.

Enhancing Return to Alpine Skiing: Integrating Perceptual-Motor-Cognitive Considerations in Testing and Progressions: A Clinical Commentary.

Alpine skiing poses significant risks for anterior cruciate ligament (ACL) injury at both recreational and professional levels, which is compounded by high rates of re-injury. Despite the existence of return to sport (RTS) and return to snow protocols, the frequency of ACL re-injury has not been mitigated, raising doubts about protocol effectiveness. Current RTS protocols primarily focus on biomechanical and neuromuscular factors in isolation, neglecting the important perceptual-motor-cognitive changes associated with ACL injuries and the high cognitive demands of skiing. The purpose of this clinical commentary is to address the perceptual-motor-cognitive demands specific to alpine skiing, evaluate RTS testing for skiers, and propose updated standards for testing and return to snow progressions that incorporate these considerations. Level of Evidence: 5.

Single bundle hamstrings autograft preparation techniques for anterior cruciate ligament reconstruction: current concepts.

Anterior cruciate ligament reconstruction (ACLR) is one of the most common orthopedic procedures, and huge variation exists in the surgical technique. Single bundle hamstrings autograft reconstruction is a common method and has good clinical outcomes. A criticism of the hamstrings autograft is a small graft diameter, often less than 8-mm, which has been associated with increased re-rupture rates. Several graft preparation techniques for single bundle hamstrings autograft exist. Perioperative decisions include the number of tendons utilized, number of graft strands, graft configuration, and femoral and tibial fixation methods. Awareness of the minimum tendon and graft length required to produce each graft variation is necessary to avoid common pitfalls. However, intraoperative graft modification is possible to maximize graft diameter, and obtain proper fixation. The objective of this current concepts review is to describe the indications, surgical anatomy, technique, intraoperative tips, clinical outcomes, and complications for single bundle hamstrings autograft preparation techniques in ACLR.

A case report of simultaneous tears of the medial and lateral posterior meniscal roots with an intact ACL graft.

INTRODUCTION AND IMPORTANCE: Meniscal root tears are defined as soft-tissue and/or osseous injuries that rip or avulse within one centimeter of the meniscal insertion to the tibial plateau. These injuries impact around 100,000 patients a year and make up 10 % to 21 % of all meniscal tears. Meniscal extrusion frequently happens when there are root rips, and the transmission of circumferential hoop loads is hampered. CASE PRESENTATION: We present one case of a 28-year-old male who complained of pain and stiffness in his left knee since 2 years after undergoing ACL reconstruction using a hamstring autograft. His examination revealed joint line tenderness on both the medial and lateral sides of the left knee. Further investigations involving X-ray and MRI established the diagnosis of both medial and lateral meniscal root tears, which were surgically managed using the transtibial pullout technique. DISCUSSION: The biomechanical implications of meniscal root tears, such as loss of hoop forces and increased tibiofemoral contact pressures, underscore the importance of timely diagnosis and management. The literature advocates surgical treatment for managing root tears, as leaving them without surgical intervention can lead to functional outcomes similar to those of total meniscectomy. CONCLUSION: This case report presents both menisci posterior root tears with an intact ACL graft which is unique in that they commonly tear in conjuction with ACL. These kind of injuries necessitates prompt diagnosis and surgical intervention to protect the knee from early arthritic changes.

Efficient handling of ACL policy change in SDN using reactive and proactive flow rule installation.

Software-defined networking (SDN) is a pioneering network paradigm that strategically decouples the control plane from the data and management planes, thereby streamlining network administration. SDN's centralized network management makes configuring access control list (ACL) policies easier, which is important as these policies frequently change due to network application needs and topology modifications. Consequently, this action may trigger modifications at the SDN controller. In response, the controller performs computational tasks to generate updated flow rules in accordance with modified ACL policies and installs flow rules at the data plane. Existing research has investigated reactive flow rules installation that changes in ACL policies result in packet violations and network inefficiencies. Network management becomes difficult due to deleting inconsistent flow rules and computing new flow rules per modified ACL policies. The proposed solution efficiently handles ACL policy change phenomena by automatically detecting ACL policy change and accordingly detecting and deleting inconsistent flow rules along with the caching at the controller and adding new flow rules at the data plane. A comprehensive analysis of both proactive and reactive mechanisms in SDN is carried out to achieve this. To facilitate the evaluation of these mechanisms, the ACL policies are modeled using a 5-tuple structure comprising Source, Destination, Protocol, Ports, and Action. The resulting policies are then translated into a policy implementation file and transmitted to the controller. Subsequently, the controller utilizes the network topology and the ACL policies to calculate the necessary flow rules and caches these flow rules in hash table in addition to installing them at the switches. The proposed solution is simulated in Mininet Emulator using a set of ACL policies, hosts, and switches. The results are presented by varying the ACL policy at different time instances, inter-packet delay and flow timeout value. The simulation results show that the reactive flow rule installation performs better than the proactive mechanism with respect to network throughput, packet violations, successful packet delivery, normalized overhead, policy change detection time and end-to-end delay. The proposed solution, designed to be directly used on SDN controllers that support the Pyretic language, provides a flexible and efficient approach for flow rule installation. The proposed mechanism can be employed to facilitate network administrators in implementing ACL policies. It may also be integrated with network monitoring and debugging tools to analyze the effectiveness of the policy change mechanism.

Cost-utility analysis of early reconstruction surgery versus conservative treatment for anterior cruciate ligament injury in a lower-middle income country.

BACKGROUND: The ideal approach for treating anterior cruciate ligament (ACL) injury is still disputed. This study aimed to determine the more cost-effective strategy by comparing early ACL reconstruction (ACLR) surgery to conservative treatment (rehabilitation with optional delayed reconstruction) for ACL injury in a lower/middle-income country (LMIC), Indonesia. METHODS: A decision tree model was constructed for cost-utility analysis of early ACLR versus conservative treatment. The transition probabilities between states were obtained from the literature review. Utilities were measured by the EQ-5D-3 L from a prospective cohort study in a local hospital. The costs were obtained from a previous study that elaborated on the burden and cost of ACLR in Indonesia. Effectiveness was expressed in quality-adjusted life years gained (QALYs). Principal outcome measure was the incremental cost-effectiveness ratios (ICER). Willingness-to-pay was set at US$12,876 - three times the Indonesian GDP per capita in 2021 - the currently accepted standard in Indonesia as suggested by the World Health Organization Choosing Interventions that are Cost-Effective criterion (WHO-CHOICE). RESULTS: The early ACLR group showed an incremental gain of 0.05 QALYs over the conservative treatment group, with a higher overall cost to society of US$976. The ICER of ACLR surgery was US$19,524 per QALY, above the WTP threshold of US$12,876. The ICER was sensitive to cost of conservative treatment, cost of ACLR, and rate of cross-over to delayed ACLR numbers in the conservative treatment group. Using the WTP threshold of US$12,876, the probability of conservative treatment being preferred over early ACLR was 64%. CONCLUSIONS: Based on the current model, early ACLR surgery does not seem more cost-effective compared to conservative treatment for ACL injury patients in Indonesia. Because the result was sensitive to the rate of cross-over probabilities from the conservative treatment alone to delayed ACLR, a future study with a long-term perspective is needed to further elucidate its impact.

Does Combined Reconstruction of the Medial Collateral and Anterior Cruciate Ligaments Provide Better Knee Function? A Systematic Review and Meta-Analysis.

Objective: This study aimed to determine if medial collateral ligament reconstruction (MCLR) alongside anterior cruciate ligament reconstruction (ACLR) preserves knee functionality better than isolated ACLR in combined ACL and MCL tears. Methods: MEDLINE, EMBASE, Scopus, CENTRAL, and Web of Science were searched systematically on 31 March 2023. Studies reporting post-operative function after ACLR and ACLR + MCLR in combined injuries were included. Outcomes included International Knee Documentation Committee (IKDC) score, side-to-side difference (SSD), Lysholm, and Tegner scale values. Results: Out of 2362 papers, 8 studies met the criteria. The analysis found no significant difference in outcomes (MD = 3.63, 95% CI: [-5.05, 12.3] for IKDC; MD = -0.64, 95% CI: [-3.24, 1.96] for SSD at 0° extension; MD = -1.79, 95% CI: [-4.61, 1.04] for SSD at 30° extension; MD = -1.48, 95% CI: [-16.35, 13.39] for Lysholm scale; MD = -0.21, 95% CI: [-4.29, 3.87] for Tegner scale) between treatments. Conclusions: This meta-analysis found no significant difference in outcomes between ACLR and ACLR + MCLR, suggesting that adding MCLR does not provide additional benefits. Due to the heterogeneity and quality of the included studies, further high-quality randomized controlled trials are needed to determine the optimal treatment for combined severe MCL-ACL injuries.

Phytochemical and biological studies on rare and endangered plants endemic to China. Part XXXVI. Tsugaforrestiacids A-O: Structurally diverse C-18 carboxylated diterpenoids from the twigs and needles of the 'vulnerable' conifer Tsuga forrestii and their inhibitory effects on ATP-citrate lyase.

An extensive phytochemical investigation on the EtOAc-soluble fraction of the 90% MeOH extract from the twigs and needles of the 'vulnerable' Chinese endemic conifer Tsuga forrestii (Forrest's hemlock) led to the isolation and characterization of 50 structurally diverse diterpenoids, including 15 unreported C-18 carboxylated ones (tsugaforrestiacids A-O, 1-15, resp.). Among them, compounds 1-7 are abieten-18-oic acids, compound 8 is an abieten-18-succinate, and compounds 10-12 are podocarpen-18-oic acids, whereas compounds 13-15 are pimarane-type, isopimarane-type, and totarane-type diterpenoid acids, respectively. Their structures and absolute configurations were determined by a combination of spectroscopic methods, GIAO NMR calculations and DP4+ probability analyses, electronic circular dichroism (ECD) data, and single crystal X-ray diffraction analyses. All the isolates were evaluated for their inhibitory activities against the ATP-citrate lyase (ACL), a key enzyme in cellular metabolism. Tsugaforrestiacids E (5) and H (8) were found to have significant inhibitory effects against ACL, with IC50 values of 5.3 and 6.2 µM, respectively. The interactions of the bioactive molecules with the ACL enzyme were examined by molecular docking studies. The isolated diterpenoids also provide chemotaxonomic evidence to support the delimitation of Tsuga from its closest sister group (Nothotsuga). The above findings highlight the importance of protecting plant species with unique and diverse secondary metabolites, which may be potential sources of new therapeutic agents for the treating ACL-associated diseases.

Interleukin Receptor Therapeutics Attenuate Inflammation in Canine Synovium following Cruciate Ligament Injury.

OBJECTIVE: In the knee, synovial fibrosis after ligamentous injury is linked to progressive joint pain and stiffness. The objective of this study was to evaluate changes in synovial architecture, mechanical properties, and transcriptional profiles following naturally occurring cruciate ligament injury in canines and to test potential therapeutics that target drivers of synovial inflammation and fibrosis. DESIGN: Synovia from canines with spontaneous cruciate ligament tears and from healthy knees were assessed via histology (n=10/group) and micromechanical testing (n=5/group) to identify changes in tissue architecture and stiffness. Additional samples (n=5/group) were subjected to RNA-sequencing to define the transcriptional response to injury. Finally, synovial tissue samples from injured animals (n=6 (IL1) or n=8 (IL6)/group) were assessed in vitro for response to therapeutic molecules directed against interleukin (IL) signaling (IL1 or IL6). RESULTS: Cruciate injury resulted in increased synovial fibrosis, vascularity, inflammatory cell infiltration, and intimal hyperplasia. Additionally, the stiffness of both the intima and subintima regions were higher in diseased compared to healthy tissue. Differential gene expression analysis showed that diseased synovium had an upregulation of immune response and cell adhesion pathways and a downregulation of Rho protein transduction pathways. In vitro application of small molecule therapeutics targeting IL1 (anakinra) or IL6 (tocilizumab) dampened expression of inflammatory and matrix deposition mediators. CONCLUSION: Spontaneous cruciate ligament injury in canines is associated with synovial inflammation and fibrosis in a relevant model for testing emerging intra-articular treatments. Small molecule therapeutics targeting IL pathways may be ideal interventions for delivery to the joint space after injury.

Heterotopic ossification postsuperficial medial collateral ligament pie-crusting: a case report.

Anterior cruciate ligament and meniscus tears are common among sports injuries. There are different techniques for addressing anterior cruciate ligament and meniscus tears, with distinct indications, advantages, and disadvantages. We present the case of a 23-year-old male who underwent right anterior cruciate ligament reconstruction and posterior horn medial meniscus repair using an all-inside technique via superficial medial collateral ligament (sMCL) pie-crusting. Clinical examination and radiological investigations a few months later identified calcifications on the medial side of the right knee. We diagnosed the patient with heterotopic ossification post-sMCL pie-crusting; no apparent causal factors were present. To our knowledge, there have been no documented instances of heterotopic ossification following sMCL pie-crusting. In conclusion, heterotopic ossification may occur after sMCL pie-crusting; further studies are needed on this subject.

Double Decker anterior cruciate ligament avulsion.

Distal anterior cruciate ligament avulsion from tibial side is an unusual injury. It can be either bony avulsion, which is more common, or rarely a soft tissue peeling of tibial spine with no bone injury. This case report represents a very infrequent injury of combined soft tissue peeling of distal anterior cruciate ligament along with bony avulsion of tibial spine in a 12-years-old boy after falling from his bike.

The association between antiphospholipid syndrome and atrial fibrillation: a single center retrospective case-control study.

Antiphospholipid syndrome (APS) is a systemic autoimmune syndrome characterized by arterial or venous thrombosis, pregnancy complications and thrombocytopenia. The aim of this study is to investigate the association between APS and atrial fibrillation (AF) among patients in Peking University People's Hospital. A single center retrospective study was conducted. Cases were hospitalized patients diagnosed with AF by a cardiologist while the control group patients did not exhibit cardiac diseases. The results of the study revealed that in multivariable logistic regression, APS, anticardiolipin antibody (aCL) positivity and anti-beta-2-glycoprotein antibody (anti-ß2GPI) positivity are independent risk factors of AF. APS, aCL positivity and anti-ß 2GPI positivity are statistically different between AF patients and non-AF patients. Forthcoming studies are needed to clarify the potential link between APS and AF.

Peroneus Longus Tendon Autografts have Better Graft Diameter, Less Morbidity, and Enhanced Muscle Recuperation than Hamstring Tendon in ACL Reconstruction.

Background: Recently the peroneus longus tendon (PLT) gained popularity in anterior cruciate ligament (ACL) reconstruction and has been utilized with satisfactory outcomes. However, there are concerns regarding donor site morbidity. This study aims to compare the functional outcome of ACL reconstruction using hamstring (HT) and PLT autografts and evaluate the donor site morbidity. Methods: Patients who underwent ACL reconstruction were allocated to two groups (HT and PLT). Graft diameter was measured intraoperatively. Knee functional outcome was evaluated with IKDC and Tegner-Lysholm scores preoperatively, and postoperatively after 3 months, 6 months, and 1 year. Donor site morbidities were assessed with thigh circumference measurements, subjective evaluation of sensory disturbances, and ankle scoring with AOFAS and FADI scores. Results: At 1-year follow-up, the PLT group showed comparable IKDC (p = 0.925) and Tegner-Lysholm (p = 0.600) scores with those of the HT group. The mean graft diameter in the PLT group (7.93 ± 0.52 mm) was larger compared with the HT group (7.43 ± 0.50 mm) (p < 0.001). The incidence of thigh atrophy (HT-16.7%, PLT-10%) and sensory disturbances (HT-73.3%, PLT-10%) was greater in the HT group. There was no significant ankle donor site morbidity in the PLT group (AOFAS-98.67 ± 3.45, FADI-99.23 ± 1.69). Conclusion: ACL reconstruction with PLT had comparable functional outcome with that of HT at 1 year. However, PLT demonstrated larger graft diameter, less donor site morbidity, and enhanced muscle recovery without significantly affecting the ankle function. PLT can be safely used as an acceptable alternative graft choice harvested from outside the knee for ACL reconstruction.

Conservative treatment versus surgical reconstruction for ACL rupture: A systemic review.

Background: Anterior cruciate ligament (ACL) rupture is a prevalent sports injury with rising rates attributed to increased population participation in sports activities. ACL rupture can lead to severe knee complications including cartilage damage, torn meniscus, and osteoarthritis. Current treatment options include conservative measures and surgical interventions. However, debates persist regarding the optimal approach. Purpose: This analysis intended to compare the function, knee stability, and incidence rate of secondary surgery between conservative and surgical treatments in ACL rupture patients. Methods: A systematic search was performed via Embase, Ovid Medline, PubMed, Cochrane Library, Web of Science, and Google Scholar for reporting outcomes of conservative and surgical treatments after ACL rupture. The outcomes included patient-reported outcome measures (PROMs), knee stability, the need for secondary meniscal surgery, delayed ACL reconstruction surgery, and revision ACL reconstruction surgery. Outcomes were analyzed using mean differences or odd ratios (OR) with 95 % CIs. Results: 11 studies were included with 1516 patients. For PROMs, our evidence indicated no differences in KOOS Pain, KOOS Symptoms, KOOS Sport/Rec, KOOS ADL, and KOOS QOL. (all p > 0.05). for knee stability, pivot shift (OR, 0.14; p < 0.001), Lachman test (OR, 0.06; p < 0.001), and tibia translation (p < 0.001) were evaluated, and the available evidence favored surgical treatment over conservative treatment. For the incidence rate of any secondary surgery after the first diagnosis, the surgical group showed a lower rate of meniscal surgery with statistical significance (OR, 0.37; p < 0.001). The average rate of revision ACL reconstruction is 5.80 %, while the rate of delayed ACL reconstruction after conservative treatment is 18.51 %. Conclusion: Currently, there is insufficient empirical evidence to advocate a systematic surgical reconstruction for any patient who tore his ACL. This review found no differences in function outcomes between conservative and surgical treatments. Regarding knee stability and secondary meniscal surgery, the results prefer the surgical treatments. The occurrence rate of revision and delayed ACL reconstruction are non-negligible factors that must be fully understood by both surgeons and patients before choosing a suitable treatment.

Association of tibial slope alterations with anterior cruciate ligament (ACL) injury and mucoid degeneration.

OBJECTIVE: To compare radiographic measurements of lateral tibial slope (LTS), medial TS (MTS), and coronal TS (CTS) in MRI-defined intact, injured, and mucoid-degenerated native ACL knees and determine inter-reader reliability. MATERIALS AND METHODS: Patient records from 2 years at tertiary care hospitals were reviewed for individuals aged 18-100 undergoing 3-Tesla knee MRI and radiographs. Two randomly selected cohorts, control, and pathologic ACLs on MRI with 86 patients each, were age, gender, and BMI-matched. A fellowship-trained musculoskeletal radiologist reevaluated curated images, characterizing ACL status. Two trained medical students independently collected clinical data and measured slopes on blinded radiographs. ICC, Cohen's kappa, and case-control matching were performed using SPSS statistical package, with ICC and ANOVA used for comparisons. RESULTS: Among 172 patients with 172 MRIs and radiographs, there were 86 controls and 86 ACL lesions. There were 108/172 (62.79%) males and 64/172 (37.21%) females. ICCs were 0.966 for MTS, 0.975 for LTS, and 0.978 for CTS. Mucoid degeneration patients had a higher BMI and were older than control (p < .05) or completely torn (p < .001) ACL patients. There was no difference in TS between normal and pathologic ACLs; however, LTS-MTS differences were larger with partial tears (2.5 ± 4.9) than normal ACLs by 4.5° (± 1.2, p < .001), complete tears by 4.5° (± 1.3, p < .001), and mucoid degeneration by 4.9° (± 1.5, p = .001). CONCLUSION: Various TS measurements are reliable. LTS-MTS differences are associated with different ACL lesions compared to normal ACLs.

Chronic Adaptions in Quadriceps Fascicle Mechanics Are Related to Altered Knee Biomechanics After Anterior Cruciate Ligament Reconstruction.

Following anterior cruciate ligament reconstruction (ACLR), patients exhibit abnormal walking mechanics and quadriceps dysfunction. Quadriceps dysfunction has been largely attributed to muscle atrophy and weakness. While important, these factors do not capture intrinsic properties of muscle that govern its ability to generate force and withstand load. While fascicle abnormalities after ACLR have been documented in early stages of recovery (<12 mo), long-term effects of ACLR on fascicle mechanics remain unexplored. We evaluated quadriceps fascicle mechanics during walking 3 years post-ACLR and examined the relationship with knee mechanics. Participants included 24 individuals with ACLR and 24 Controls. Linear mixed models compared the ACLR, Contralateral, and Controls limbs for (1) quadriceps strength, (2) fascicle architecture and mechanics, and (3) knee mechanics. No difference in strength or overall fascicle length excursions was found between limbs. The ACLR limb exhibited longer fascicles at heel strike and peak knee extension moment (P < .001-.004), and smaller fascicle angles at heel strike, peak knee extension moment, and overall suppressed fascicle angle excursions (P < .001-.049) relative to the Contralateral and/or Control limb. This indicates an abnormality in fascicle architecture and mechanics following ACLR and suggests abnormalities in contractile function that cannot be explained by muscle weakness and may contribute to long-term gait irregularities.

Beyond weakness: Exploring intramuscular fat and quadriceps atrophy in ACLR recovery.

Muscle weakness following anterior cruciate ligament reconstruction (ACLR) increases the risk of posttraumatic osteoarthritis (OA). However, focusing solely on muscle weakness overlooks other aspects like muscle composition, which could hinder strength recovery. Intramuscular fat is a non-contractile element linked to joint degeneration in idiopathic OA, but its role post-ACLR has not been thoroughly investigated. To bridge this gap, we aimed to characterize quadriceps volume and intramuscular fat in participants with ACLR (male/female = 15/9, age = 22.8 ± 3.6 years, body mass index [BMI] = 23.2 ± 1.9, time since surgery = 3.3 ± 0.9 years) and in controls (male/female = 14/10, age = 22.0 ± 3.1 years, BMI = 23.3 ± 2.6) while also exploring the associations between intramuscular fat and muscle volume with isometric strength. Linear mixed effects models assessed (I) muscle volume, (II) intramuscular fat, and (III) strength between limbs (ACLR vs. contralateral vs. control). Regression analyses were run to determine if intramuscular fat or volume were associated with quadriceps strength. The ACLR limb was 8%-11% smaller than the contralateral limb (p < 0.05). No between-limb differences in intramuscular fat were observed (p 0.091-0.997). Muscle volume but not intramuscular fat was associated with strength in the ACLR and control limbs (p < 0.001-0.002). We demonstrate that intramuscular fat does not appear to be an additional source of quadriceps dysfunction following ACLR and that muscle size only explains some of the variance in muscle strength.

Clinico-Radiological Correlation Between Anterior Cruciate Ligament Deficiency and Hyperextension of the Knee Joint: A Prospective Study.

INTRODUCTION: The anterior cruciate ligament (ACL) primarily restricts anterior sliding of the tibia over the fixed femur, thereby also postulating to prevent hyperextension of the knee joint. The main objective of our study was to identify the role of the ACL in the prevention of knee hyperextension and to quantify the amount of hyperextension caused by an ACL tear, apart from its well-established role in the prevention of anterior tibial translation on the fixed femur. METHODS:  This prospective study was conducted in a tertiary care hospital. Eighty patients with unilateral ACL tears were assessed clinico-radiologically in the preoperative period to quantify the knee hyperextension, which was then compared with the uninjured contralateral knee of the same patient. Posterior tibial slope and notch width index were also assessed to rule out bias in our study. RESULTS: The mean age of patients in our study was 27.3 years. Out of 80 patients, 70 were male and 10 were female. The Pearson coefficient for clinically and radiologically assessed hyperextension was 0.919 (p-value 0.001) and 0.910 (p-value 0.001), respectively. Posterior tibial slope and notch width index assessment showed Pearson coefficients of -0.018 (p-value 0.887) and -0.068 (p-value 0.547), respectively. CONCLUSION: Anterior cruciate ligament complete tear or deficiency produces knee hyperextension, which varies from patient to patient. Though the amount of hyperextension produced is mild (less than five degrees in most patients), it can cause a significant amount of knee instability. Hence, correction of knee hyperextension is crucial while performing ACL reconstruction.

A Comparative Analysis of Quadriceps Tendon, Patellar Tendon Bone Allograft, and Cadaver Graft in Anterior Cruciate Ligament (ACL) Repair and Reconstructive Surgery.

Anterior cruciate ligament (ACL) injuries are a common occurrence among athletes and active individuals, often necessitating surgical intervention for optimal recovery. The choice of graft material for ACL reconstruction remains a topic of debate, with various options available, including quadriceps tendon (QT), patellar tendon bone allograft (PTBA), and cadaver graft (CG). This paper aims to provide an extensive review and comparison of the efficacy, outcomes, and complications associated with these graft types based on recent research. A systematic literature search following PRISMA guidelines was conducted to identify relevant studies published in the past six years. The findings suggest that while each graft type has its advantages and limitations, there is no definitive superior choice. Factors such as patient age, activity level, comorbidities, and surgeon preference should be considered when selecting the most appropriate graft for ACL repair surgery. QT grafts are associated with lower donor-site morbidity compared to patellar tendon grafts. However, QT grafts may have a higher risk of graft rupture and decreased knee flexion strength. PTBA grafts, compared to QT grafts, have a higher risk of donor-site morbidity but a lower risk of graft rupture and improved knee stability. CG grafts have lower donor-site morbidity compared to PTBA grafts but may have a higher risk of graft rupture and decreased knee flexion strength compared to PTBA grafts. In conclusion, the choice of graft material for ACL reconstruction is a complex decision that requires careful consideration of various factors, including patient age, activity level, comorbidities, and surgeon preference. While each graft type has its advantages and limitations, there is no definitive superior choice. Therefore, it is essential to carefully weigh the risks and benefits of each graft type to ensure optimal outcomes for patients undergoing ACL repair surgery.

Rehabilitation Following ACL Repair with Internal Brace Ligament Augmentation in Female Gymnast: A Resident's Case Report.

Introduction: Anterior Cruciate Ligament (ACL) injuries continue to be a major source of morbidity in gymnastics. The gold standard is to perform an ACL Reconstruction (ACLR). However, injuries to the proximal femoral attachment of the ACL have demonstrated an ability to regenerate. An alternative surgical intervention to the ACLR in this ACL tear subgroup is an ACL repair. The purpose of this case report is to provide a rehabilitation progression for a female gymnast after an ACL repair with Internal Brace Ligament Augmentation (IBLA). Case Description: The subject was a 16-year-old female who presented with a Sherman Type 1 proximal avulsion of her ACL. She underwent an ACL repair with IBLA. Physical therapy interventions followed a sequential and multi-phased approach based on time for tissue physiologic healing and individual progression. Patient reported outcomes including the International Knee Documentation Committee (IKDC), the Anterior Cruciate Ligament Return to Sport After Injury (ACL-RSI) and the Optimal Screening for Prediction of Referral and Outcome Yellow Flag (OSPRO-YF) were assessed in conjunction with isokinetic strength and hop performance testing to determine return to sport readiness. Outcomes: The subject completed 42 sessions over the course of 26 weeks in addition to a home exercise program. At return to sport, clinically meaningful improvement was observed in patient reported outcomes including the IKDC, ACL-RSI, and OSPRO-YF. Additionally, strength and hop performance surpassed established thresholds of clinical significance. The subject returned to sport at six months post-operatively. Conclusion: The subject in this case report returned to full participation in gymnastics six months after an ACL repair with internal bracing following a sequential and multi-phased rehabilitation. The primary ACL repair with IBLA appeared beneficial to this patient and could benefit from additional study in other athletes and athletic populations. Level of Evidence: Level 5.