ACL Reconstruction Research Articles

Preoperative knee hyperextension is the most relevant predictor for ACL reconstruction objective failure: a machine learning analysis of 680 patients

Objectives To evaluate the predictive performance of different machine learning algorithms for the occurrence of objective failure in ACL reconstruction and to identify the most relevant predictors associated with this outcome. Methods We evaluated 680 patients submitted submitted to ACL reconstruction between January 2012 and July 2021. The study outcome was ACL objective failure, defined as a complete tear confirmed by MRI or arthroscopy evaluation or clinically ACL insufficiency. Routinely collected imaging, clinical, and demographic data were used to train 9 machine learning algorithms (k-nearest neighbors (KNN) classifier, decision tree classifier, random forest classifier, extra trees classifier, gradient boosting classifier, Light Gradient Boosting Machine (LightGBM), eXtreme Gradient Boosting (XGBoost), CatBoost classifier, and logistic regression). We used a random sample of 70% of patients to train the algorithms, and 30% were left for performance assessment, simulating new data. The performance of the models was evaluated with the area under the receiver operating characteristic curve (AUC). Results The predictive performance of all models was good, with AUC’s ranging from 0.81 to 0.88. The models with the best AUC metric were the Gradient Boosting Classifier (0.88 [95% CI, 0.81 to 0.92]) and Random Forest Classifier (0.88 [ 95% CI, 0.81 to 0.92). Knee hyperextension consistently emerged as the primary predictor across all models subjected to our analysis. Conclusion Machine learning algorithms demonstrated good performance to predict ACL reconstruction objective failure. Additionally, knee hyperextension consistently emerged as the primary predictor across all models subjected to our analysis.

Combined Anterior Cruciate Ligament and Anterolateral Ligament Reconstruction Using the Rectus Femoris Tendon: Surgical Technique

Objectives: Present a combined ACL and anterolateral ligament (ALL) reconstruction technique using a rectus femoris tendon graft harvested in a minimally invasive approach without specialized instruments. Methods: The graft is harvested from the lateral portion of the rectus femoris tendon. The distal end is detached from the patella, and dissection is extended proximally by 8 cm, ensuring preservation of the intermediate and deep layers of the quadriceps tendon (QT). A closed tendon stripper is carefully pushed with the knee at 20 degrees of flexion. The graft is folded asymmetrically, with the distal portion forming a double or triple graft for the ACL, and the proximal portion remaining unfolded for the ALL. The femoral tunnel is made using an outside-in technique, replicating both the ACL and ALL footprints. Results: The graft length typically ranges from 28 to 35 cm, and the ACL portion diameter ranges from 8 to 10 mm. The technique showed a low rate of complications and provided adequate control of pivot shift. Advantages include predictable graft diameter, use of standard instruments, and preservation of hamstring strength. Disadvantages include potential quadriceps strength reduction, risk of hematoma, an additional incision, and the need for an extra screw for ligament fixation. Conclusion: To our knowledge, this is the first report of a combined ACL and ALL reconstruction technique using a QT graft. The minimally invasive rectus femoris graft approach offers a viable alternative for combined ACL and ALL reconstruction in both primary and revision surgeries.

Functional Outcomes in ACL Reconstruction: A Randomized Controlled Trial Comparing All-Inside and Transportal Techniques.

The two techniques to fix a torn ACL are the Transportal and All-Inside Techniques. However, the argument about which method is better for functional outcomes keeps going on. The aim was to look at how well these two treatments worked and their effects. We hypothesized that All-Inside and Transportal ACL reconstruction procedures would yield similar functional results. The study included 45 patients with ACL insufficiency from AIIMS, Raipur, India. Half of each ACL approach was represented by 22 AI and 23 TP participants, randomly assigned to each group. Preoperative and post-operative VAS, IKDC, and range of motion were determined at 1, 3, and 6 months. The study used IBM SPSS v20 for Data Analysis, comparing two groups using a t-test. P < 0.05 was fixed for Statistical significance. The study was dominated by young males (86.7%, 18-30 years), mainly students (44.4%). Comparable IKDC scores over time (P = 0.628); significant VAS score difference (P = 0.001). A similar movement range (P = 0.153) was observed. AI group had slightly smaller grafts (non-significant, P = 0.235). Similar Lachmann Grade distributions pre- and post-surgery; no significant post-operative complication in either group. When comparing the methods' functionalities, no statistically significant gaps emerged. All-Inside approach preserves bone and gracilis tendon, reduces post-operative pain, and strengthens knee flexors. Although, early rehabilitation favors all inside, both methods are equally effective over time. In comparison to the traditional Transportal Technique, All Inside has a greater learning curve and costs more.

Is a Pre-Operative MRI Anterolateral Ligament Injury Related to Anterior Cruciate Ligament Reconstruction Failure? A Prospective Cohort Study with Minimum 5 Year Follow Up

Objectives To evaluate the clinical outcomes and failure rate of ACL reconstruction in patients with and without ALL injury diagnosed by magnetic resonance imaging (MRI) at a minimum five year follow up Methods A prospective cohort of patients with acute ACL injury was divided into 2 groups based on the presence (ALL injury group) or absence (Control group) of ALL injury on preoperative MRI. Both groups underwent reconstruction of the ACL with autologous hamstrings grafts. The Lysholm and subjective International Knee Documentation Committee (IKDC) scores, KT-1000 and pivot shift tests, reconstruction failure rate, incidence of contralateral ACL injury, presence of associated meniscal injury and presence of knee hyperextension were evaluated. Results A total of 156 patients were evaluated. No significant preoperative differences were found between the groups. In the postoperative evaluation, patients in the control group had a lower reconstruction failure rate (14.3% vs 4.6%; P = .049) and better clinical outcomes according to the Lysholm scores (85.0 ± 10.3 vs 92.3 ± 6.3; P &lt; .0001). Although the pivot shift was similar, KT-1000 revealed worse results for the ALL injury group (2.8 +/- 1.4 mm) compared to the control group (1.9 +/- 1.3 mm) (p = 0.00018). Patients in the ALL injury group also presented a worsening of the knee instability from two to five years according to the KT-1000 (2.4 +/- 1.6 vs 2.8 +/- 1.4; p=0.038). Conclusion Combined ACL and ALL injuries were associated with significantly less favorable outcomes than were isolated ACL injuries at a minimum follow-up of 5 years after ACL reconstruction. Patients with concomitant ALL injury showed a higher rerupture rate and worse functional scores. Also, knee stability tends to worsen from 2 to 5 years in cases of associated ALL injury.

Early Surgical Intervention Results in Better Patient-Reported Outcomes Than Delayed Treatment in Patients Undergoing Anterior Cruciate Ligament Reconstruction in the Presence of Concomitant Medial Collateral Ligament Injury

PurposeTo investigate the influence of the timing of ACL reconstruction (ACLR) on patient-reported outcomes, comparing those with and without concomitant medial collateral ligament (MCL) injury. MethodsThis study included patients who underwent ACLR between September 2015 and October 2020. Inclusion criteria required patients to have preoperative and postoperative patient-reported outcome measures (PROMs) and a follow-up period of at least 2 years. Patients who sustained a grade 2 or 3 MCL injury with an ACL tear were compared to patients with no MCL injury as a control. All patients underwent ACL reconstruction using either bone-tendon-bone (BTB) autograft or BTB Allograft. Patient-reported outcomes (International Knee Documentation Committee (IKDC), Lysholm, and Knee Osteoarthritis and Score (KOOS)) were recorded, and outcomes were analyzed by sex and time from index injury. A stratified linear mixed-effects regression analysis was conducted. ResultsA total of 253 eligible patients with 2-year outcomes were enrolled. Combined ACL/MCL injury had lower IKDC (β=-6.1 vs β=-8.3, p=0.003), KOOS QOL (β=-9.3 vs β=-11, p=0.004), and KOOS Sport (β=-12 vs β=-13 , p=0.08) if performed after 6 weeks from index injury. Isolated ACL injuries showed lower KOOS ADL (β=-2.4, p=0.045) if surgery performed between 3-6 months. For combined ACL/MCL injury, autograft (compared to allograft) was found to have worse IKDC (β=-11 (-18, -4.2), p=0.002), Lysholm (β=-9.2 (-15, -3.1), p=0.004), KOOS QOL(β=-11 (-20, -1.6), p=0.023), KOOS Pain (β=-5.1 (-10, -0.03), p=0.049), KOOS Symptoms (β=-7.6 (-10, -0.03), p=0.02), and KOOS Sports (β=-21 (-32, -10), p=<0.001). ConclusionPatients undergoing ACL reconstruction with a grade 2 or 3 MCL injury have improved patient-reported outcomes if surgery is performed within 6 weeks from the time of injury. In this cohort, allografts resulted in better outcome scores compared with autografts. Level of EvidenceLevel III Retrospective Cohort Study

Advanced Neuromuscular Training Differentially Changes Performance on Visuomotor Reaction Tests and Single-leg Hop Tests in Patients with ACL Reconstruction.

Advanced neuromuscular training prepares patients with anterior cruciate ligament reconstruction (ACLR) for sport participation. Return-to-sport testing often includes single-leg hop tests, yet combining motor and cognitive tasks (i.e., dual-task) might reveal neurocognitive reliance. This study examined changes in performance on visuomotor reactions tests and single-leg hop tests following advanced neuromuscular training in patients with ACLR. The hypothesis was that performance would improve less on reaction tests than on single-leg hop tests. Quasi experimental, Pretest-Posttest. Twenty-five patients with ACLR (11 males) completed 10 sessions of advanced neuromuscular training and pre-and post-training testing. Reaction tests outcomes were from a platform and visual display. The double-leg reaction test involved touching target dots with either leg for 20 seconds; correct touches and errors were recorded. The single-leg reaction test involved hopping on the test leg to 10 target dots; hop time and errors were recorded. Single-leg hop tests included forward, triple, crossover triple, and timed hop; limb symmetry index was recorded. Effect sizes were calculated for corrected touches on the double-leg reaction test, surgical side hop time on the single-leg reaction test, and surgical side hop distance or time on single-leg hop tests. Correct touches on the double-leg reaction test significantly increased from pre- to post-training (20.4 +/- 4.3 vs.23.9 +/- 2.8, p<0.001). Hop time on the single-leg reaction test significantly decreased from pre- to post-training (Surgical leg 13.2 vs.12.3 seconds, non-surgical leg 13.0 vs.12.1 seconds, p=0.003). Mean errors did not significantly change on either reaction test (p> 0.05). Cohens d effect sizes in descending order was single-leg hop tests (d=0.9 to 1.3), double-leg reaction test (d=0.9), and single-leg reaction test (d=0.5). Motor performance improved after advanced neuromuscular training, but the effect size was less on visuomotor reaction tests than single-leg hop tests. The results suggest persistence of neurocognitive reliance after ACLR and a need for more dual-task challenges in training. 3.

Youth Soccer Players Undergoing Anterior Cruciate Ligament Reconstruction Demonstrate High Rates of Continuation of Sport and Progression to Professional Level Soccer: A Seven Season Analysis in Twenty-Nine Brazilian Professional Soccer Teams

Objectives To evaluate the progression of youth male soccer athletes who undergo ACL reconstruction and track their progression from youth up to professional level play Methods 163 male players from 29 soccer teams underwent ACL reconstruction and were followed from 2015 to 2023. They were evaluated regarding category progression (under-13 to professional), type of graft used, presence of re- rupture, and return to sport/continuation of sport. Results Most injuries occurred in players in the under-17 (31.3%) and under-20 (47.2%) categories. A total of 111 patients continued playing after ligament reconstruction (68.1%), and 52 patients discontinued their careers (31.9%). Of the 163 athletes who underwent ACL reconstruction, 40 still play professionally (24.5%) and 71 are continuing participation in youth soccer and may still become professionals (43.6%). Among the professionals, 8 underwent an ACL revision reconstruction. The graft of choice in 77.3% of the reconstructions were the hamstring tendons. Conclusion Athletes from professional soccer teams who underwent ACL reconstruction while still playing in the youth teams of their clubs demonstrated a return to sport rate of 68.1%. Among players who returned to sport and became adult league professionals, 40 (83.3%) continued to play at the adult professional level, and 8 (16.7%) have discontinued their careers.

MCL pie crusting for concomitant medial meniscal surgery does not appear to adversely influence primary ACL reconstruction functional outcomes

ObjectivesMedial collateral ligament “pie-crusting” (MCLPC), selective release of the superficial MCL, has been shown to improve the arthroscopic access to the posterior horn of the medial meniscus without adversely affecting the outcomes of isolated meniscal surgery. However, whether MCL PC, to address concomitant meniscal lesions during anterior cruciate ligament reconstruction (ACLR) surgery, adversely affects ACLR outcomes is unknown. The aim of this study was to assess whether patients who had undergone MCLPC at the time of ACLR had similar post outcomes to patients undergoing isolated ACLR. Methods55 consecutive patients (33 male and 22 female), with minimum 2-year follow-up, who had undergone MCLPC with concomitant primary ACLR (PC group) were retrospectively matched on the basis of age, sex and follow-up with 55 patients who underwent isolated primary ACLR. Post-operative outcome measures (PROMs) included the Knee injury and Osteoarthritis Outcome Score, the International Knee Documentation Committee score, Tegner activity score, the EuroQol five-dimension health questionnaire and EuroQol visual analogue scale. ResultsThe two groups’ median postoperative EQ 5D-VAS, EQ 5D-index and Tegner scores were similar. The difference between pre-operative and post-operative KOOS scores was similar for the two group for all subscales except the ADL subscale which was higher in the MCLPC group (24, IQR ​= ​6–32) than in the isolated ACLR group (5, IQR ​= ​0–9.74). The median post op IKDC score was 84 in the MCLPC group and compared with 90 in the isolated ACLR group. However, the difference between pre-operative and post-operative IKDC scores was higher in patients in the MCLPC group (40, IQR ​= ​25–49) than in the isolated ACLR group (32, IQR ​= ​19.6–46.8). ConclusionsMCLPC, performed at the time of ACLR does not appear to adversely affect the functional post-operative outcomes. Level of evidenceIV.

A Novel Machine Learning Model to Predict Revision ACL Reconstruction Failure in the MARS Cohort.

As machine learning becomes increasingly utilized in orthopaedic clinical research, the application of machine learning methodology to cohort data from the Multicenter ACL Revision Study (MARS) presents a valuable opportunity to translate data into patient-specific insights. To apply novel machine learning methodology to MARS cohort data to determine a predictive model of revision anterior cruciate ligament reconstruction (rACLR) graft failure and features most predictive of failure. Cohort study; Level of evidence, 3. The authors prospectively recruited patients undergoing rACLR from the MARS cohort and obtained preoperative radiographs, surgeon-reported intraoperative findings, and 2- and 6-year follow-up data on patient-reported outcomes, additional surgeries, and graft failure. Machine learning models including logistic regression (LR), XGBoost, gradient boosting (GB), random forest (RF), and a validated ensemble algorithm (AutoPrognosis) were built to predict graft failure by 6 years postoperatively. Validated performance metrics and feature importance measures were used to evaluate model performance. The cohort included 960 patients who completed 6-year follow-up, with 5.7% (n = 55) experiencing graft failure. AutoPrognosis demonstrated the highest discriminative power (model area under the receiver operating characteristic curve: AutoPrognosis, 0.703; RF, 0.618; GB, 0.660; XGBoost, 0.680; LR, 0.592), with well-calibrated scores (model Brier score: AutoPrognosis, 0.053; RF, 0.054; GB, 0.057; XGBoost, 0.058; LR, 0.111). The most important features for AutoPrognosis model performance were prior compromised femoral and tibial tunnels (placement and size) and allograft graft type used in current rACLR. The present study demonstrated the ability of the novel AutoPrognosis machine learning model to best predict the risk of graft failure in patients undergoing rACLR at 6 years postoperatively with moderate predictive ability. Femoral and tibial tunnel size and position in prior ACLR and allograft use in current rACLR were all risk factors for rACLR failure in the context of the AutoPrognosis model. This study describes a unique model that can be externally validated with larger data sets and contribute toward the creation of a robust rACLR bedside risk calculator in future studies. NCT00625885 (ClinicalTrials.gov identifier).

The relationship between knee joint effusion and quadriceps strength and activation after anterior cruciate ligament (ACL) injury and reconstruction.

Knee joint effusion and quadriceps strength and activation deficits are common consequences of anterior cruciate ligament (ACL) injury and reconstruction. The presence of an effusion may initiate or worsen the quadriceps dysfunction present after ACL trauma. In simulated effusion studies, evidence indicates an inverse relationship between effusion size and quadriceps dysfunction. While this relationship was not found in patients after ACL injury, prior research was limited by a subjective clinical assessment of effusion grade. The purpose of this study was to determine if the size of the knee joint effusion, measured via ultrasound, after ACL injury and reconstruction influences quadriceps strength and activation. Descriptive Laboratory Study. Research Laboratory. 41 individuals (23 females, age=21.8±7.5years, height =171.7±7.9cm, 15 mass =72.3±14.2kg), with an ACL injury reported for 2 sessions [one before 16 reconstruction and one ∽16 weeks after ACL reconstruction]. Three ultrasound images of the suprapatellar pouch and three trials of quadriceps strength and activation using the interpolated twitch technique were gathered from the ACL knee. Effusion cross-sectional area was measured using ImageJ, averaged and inputted into linear regression models to predict muscle strength and interpolated twitch activation. Analyses were considered significant at p≤0.05. No relationship was found between effusion size and strength (R2 = 0.086) or activation (R2=0.056) after ACL injury (p>0.05). After reconstruction, however, there was a small negative relationship between effusion size 24 and activation (R2=0.122; Standardized β=-0.349; p=0.025), while no relationship was found for effusion size and strength (R2=0.000; p≤0.05). The size of the effusion after ACL injury does not influence strength or activation. However, after ACL reconstruction, effusion size does have a small influence on quadriceps activation, with a larger effusion being related to lower activation. Prior research using simulated effusions appear to overestimate the effects of effusion on quadriceps function.

A comparative study of functional and radiological outcome on aperture versus suspensory femoral fixation in Arthroscopic ACL reconstruction

Objectives To compare and find the superiority between aperture and suspensory of femoral fixation in ACL reconstruction. Material and Methods A comparative study with a study population with 30 in each group with Tengner Lyscholm and International Knee Documentation Committee (IKDC) subjective scoring between each group for a followup of 3 years. Results No statistically significant difference between two groups functionally and radiologically. Conclusion Both methods are equally good if correct surgical techniques are followed in both groups.

Comparison of blood flow restriction training rehabilitation and general rehabilitation exercise after anterior cruciate ligament reconstruction: A meta-analysis of randomized controlled trials.

Blood flow restriction training (BFRT) has been found to reduce quadriceps atrophy and weakness after anterior cruciate ligament (ACL) surgery. However, the clinical benefit of BFRT as compared to general rehabilitation exercise (GRE) alone remains uncertain. This study aimed to compare the effects of BFRT and GRE on ACL reconstruction rehabilitation through a meta-analysis of randomized controlled trials. PubMed, Web of Science, EMBASE, Elsevier and Biosis were searched for randomized controlled trials comparing BFRT and GRE following ACL reconstruction. Primary outcomes included muscle strength (extensor and flexor muscle general strength), Lysholm score, the International Knee Documentation Committee (IKDC) score, extensor muscle torque (peak torque and average torque) and muscle cross-sectional area (CSA). The secondary outcomes included a range of motion (ROM), pain, Y-balance and the Patient-Reported Outcomes Measurement Information System (PROMIS). Thirteen randomized controlled trials involving 376 participants were included. The change in muscle strength (Mean difference, MD: 12.96, 95% confidence interval, [95% CI]: 7.02-18.91, heterogeneity, I2 = 39%), Lysholm score (MD: 9.41, 95% CI: 8.93-9.88, I2 = 40%) and IKDC score (MD: 9.88, 95% CI: 0.57-19.19, I2 = 87%) of the BFRT group were superior to that of the GRE group at the time of last follow-up. However, no significant difference was found between the BFRT and the GRE groups regarding the change in muscle CSA, ROM, extensor muscle torque, pain score, Y-balance and PROMIS. BFRT seems to perform better than GRE in terms of functional improvement and muscle strength following ACL reconstruction, but there seems to be no significant difference between them in terms of joint mobility, pain relief, stability improvement and patient's perception of their disease and treatment. Level II.

The Impact of Anterior Cruciate Ligament Tear on Player Performance and Longevity in La Liga League Soccer Players

AbstractAnterior cruciate ligament (ACL) rupture is among the most studied sports injuries. We investigate the impact of ACL reconstruction (ACLR) on performance and longevity in La Liga to elucidate performance parameters impacted after surgery in professional soccer players and variables impacting return-to-play (RTP).Demographic and performance data for La Liga players with ACLR between 1993 and 2020 were collected three seasons before and after injury and compared with two healthy controls. Analysis was conducted between and within ACLR and control groups. Pearson's correlation coefficients and a multiple linear regression model analyzed relationships between demographic variables and RTP.After exclusion, 23 professional soccer players were identified for the ACLR group. One year after index, ACLR had lower goals, shots on-target, assists, pass percentage, tackles, tackle success percentage, blocks, and clearances compared with control (p &lt; 0.05). Two years after index, ACLR had lower assists, pass percentage, and tackle success percentage than control (p &lt; 0.05). Three years after index, ACLR had fewer matches and blocks versus control (p &lt; 0.05). Pearson's correlation showed a positive correlation between experience and RTP (p = 0.001). Multiple linear regression found RTP to increase 32.66 days for each additional year of experience (p &lt; 0.001).With performance metrics showing significant decreases up to 2 years post-ACLR but largely recovering within 3 years of RTP, results support that soccer players undergoing ACLR eventually recover to preinjury levels of play. Players should be counseled on initial declines in performance metrics the first few years after RTP.

Lower limbs kinematic analysis during a jump landing task in soccer players with unilateral anterior cruciate ligament reconstruction

BackgroundFatigue leads to an acute decline in muscle strength, altered patterns of lower extremity muscle activation, changes in hip and knee kinematics. In terms of the effects of fatigue on knee joint kinematics during plyometric training, there is still a lack of knowledge regarding kinematic differences between athletes who passed the ACL reconstructions rehabilitation period and healthy athletes. Therefore, this study aimed to compare lower limb joint kinematic parameters between reconstructed cruciate ligament and healthy control soccer players during jump landing in a fatigued setting.MethodsLower limb kinematic parameters were recorded in 20 professional soccer players (age, 24.95 ± 2.92 years; body mass, 77.20 ± 12.88 kg; height, 1.77 ± 3.19 m) during jump landing task before and after the fatigue protocol. The control group consisted of healthy subjects and the experimental group consisted of subjects with ACL reconstruction by thigh transplantation. Kinematic data was recorded with 4 cameras to measure lower limb angles at first foot contact and maximum range of motion.ResultsThe results showed that before fatigue, there was only a significant difference between the two groups in the maximum range of motion of the non-involved hip joint (P = 0.022) and angle of the involved hip at first contact (P = 0.049). In other data on joint range of motion or initial contact angle, no significant difference was observed between the two groups (P > 0.05). After fatigue protocol, there was a significant difference in initial foot contact in non-involved (P = 0.030), and involved (P = 0.020) hip joint angles between the two groups. However, no significant difference in initial contact angle or range of motion of other joints was observed between the groups.ConclusionsThis study shows that plyometric fatigue does not contribute to numerous changes in contact angles and range of motion in lower extremity joints in healthy soccer players and those with a history of cruciate ligament repairs.

An ultrastructure analysis of the developing human anterior cruciate ligament tibial enthesis.

This study aimed to investigate the ultrastructural anatomy of the developing ACL tibial enthesis. We hypothesized that enthesis architecture would progressively mature and remodel, eventually resembling that of the adult by the early postnatal stage. Five fresh-frozen human pediatric cadaveric knees aged 1-36 months underwent anatomical dissection to harvest the ACL insertion and underlying tibial chondroepiphysis. The samples were prepared for scanning electron microscopy (SEM) to examine the ultrastructural anatomy of the enthesis and underwent histological staining for circular polarized light (CPL) and light microscopy imaging. SEM analysis of the 1- and 8-month-old samples revealed a shallow interdigitation between the dense fibrous (ligamentous) tissue and unmineralized chondrogenic tissues, with a minimal transition zone. By 11-month, a more complex transition zone was present. By age 19- and 36-month-old, a progressively more complex and defined fibrocartilage zone was observed. CPL analysis revealed distinct collagen fiber continuity, alignment, and organization changes over time. By 19 and 36 months, the samples exhibited complex fiber arrangements and a progression toward uniform fiber orientation. Similarly, histological analysis demonstrated progressive remodeling of the enthesis with increasing age. Our results suggest that the ACL enthesis of the developing knee begins to mimic that of an adult as early as 19 months of age, as a more complex transition between ligamentous and chondro-epiphyseal tissue can be appreciated. We hypothesize that the observed changes are likely due to mechanical loading of the enthesis with the onset of weightbearing. Future investigations of ACL reconstruction and repair will benefit from improved understanding of the chondro-epiphyseal/ACL regions.

Never Assume Successful Treatment of Septic Arthritis: Bacteria Isolated at Revision ACL Reconstruction 3 Years After Primary ACL Reconstruction "Successfully" Treated for Infection.

Level IV.

Magnetic Resonance Imaging Can Predict Hamstring or Quadriceps Tendon Autograft Diameter in Pediatric or Adolescent Anterior Cruciate Ligament Reconstruction: A Systematic Review.

Insufficient graft diameter is an important factor that contributes to failure rates after anterior cruciate ligament reconstruction (ACLR). Although modalities, such as magnetic resonance imaging (MRI), have been well investigated in the adult population to predict graft diameter preoperatively, it is unclear whether similar strategies can be used in the pediatric population. This review aims to evaluate the utility of MRI in the preoperative estimation of autograft parameters in pediatric or adolescent patients undergoing ACLR. Three databases were searched on January 31, 2024. The authors adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Revised Assessment of Multiple Systematic Reviews guidelines and the Cochrane Handbook for Systematic Reviews of Interventions. Data on demographics, graft characteristics, MRI imaging techniques, and statistical analyses correlating MRI parameters with graft length or diameter were recorded. Five studies consisting of 450 patients were included in this review (48.4% females). The mean (SD) age at ACLR was 14.7 (6.8) years. Three studies using hamstring tendon (HT) autografts found that combined semitendinosus and gracilis tendon cross-sectional area (ST+GT CSA) were able to predict graft diameter. One study reported an ST+GT CSA cutoff of 31.2mm2 to have an 80% and 74% sensitivity and specificity, respectively, in predicting HT autograft diameter above 8mm. Two studies using quadriceps tendon (QT) autografts found that tendon thickness on sagittal MRI view was able to predict graft diameter. One study reported a QT cutoff of 6.7mm to have 97.5% and 46.6% sensitivity and specificity, respectively, in predicting the diameter of the QT graft to be above 8mm. Associations between MRI parameters and graft length were not reported. Although there is limited evidence, ST+GT CSA and QT thickness on sagittal view on MRI can be used to predict intraoperative HT and QT autograft diameter, respectively, in pediatric or adolescent ACLR. Future investigations should investigate correlations between imaging parameters and graft length, especially when using QT autografts in the pediatric population. Level III.

Limb dominance influences landing mechanics and neuromuscular control during drop vertical jump in patients with ACL reconstruction.

The purpose of this study was to compare the interlimb biomechanical differences in patients who had undergone anterior cruciate ligament reconstruction (ACLR) in either dominant (ACLR-D) or nondominant (ACLR-ND) limbs and healthy controls (CON) during drop vertical jump (DVJ) task. To investigate whether the dominant or nondominant limb influences the risk of re-injury in ACLR patients. Thirty-three ACLR patients were divided into ACLR-D and ACLR-ND groups according to whether the surgical limb was dominant or nondominant. Seventeen healthy individuals were selected as the CON group. Three-dimensional kinematic data, ground reaction force (GRF) data, and surface electromyographic (EMG) data from the bilateral lower limbs of all participants were collected during the DVJ task. Two-way repeated-measures ANOVAs (limb × group) were performed on the variables of interest to examine the main effects of limb (dominant vs. nondominant) and group (ACLR-D, ACLR-ND, and CON), as well as the interaction between limb and group. The nonsurgical limbs of ACLR group had significantly greater knee valgus angles, knee extension and valgus moments, peak posterior GRF (PPGRF), and peak vertical GRF (PVGRF) compared to the surgical limbs. The nonsurgical limbs of ACLR-ND patients demonstrated significantly greater knee extension and valgus moments, greater PPGRF and PVGRF, and reduced muscle activity in the vastus medialis and vastus lateralis compared to the CON group. The ACLR patients had reduced muscle activity in the quadriceps of the surgical limb and the hamstrings of the bilateral limbs compared to controls. The nonsurgical limbs of ACLR patients may suffer an increased risk of ACL injury due to altered landing mechanics and neuromuscular control strategies compared to the surgical limbs. Additionally, limb dominance influences movement patterns and neuromuscular control during DVJ task, the nonsurgical limbs of the ACLR-ND might be at higher risk of ACL injury compared to the ACLR-D group.

The Incidence and Rate of Return to Competitive Sport Post ACL Reconstruction: Literature Review

ACL injuries are common in competitive team-ball athletes and are frequently career ending or compromising. The rate of return to competitive sport after ACL injury/management is debatable as well as the surgical and rehabilitation factors that should be considered while managing ACL injuries in order to optimize the return of the athlete to competition. The aim of this research was to investigate the incidence and the rate of return to competitive sport after ACL injury and to explore the various factors which need to be considered in ACL surgery and rehabilitation to support the process of successful return to competitive play. Research aims were met through extensive review of relevant ACL management literature. The rate of return to competitive sport averages around half of the athletes operated for ACL injury with a high rate of re-injuries especially within the first six months after surgery. Proper tunneling technique is an important surgical factor in relation to return to sport and surgery should be done as early as the knee is fully extended addressing all the concomitant injuries. Rehabilitation should be individualized, gradual and comprehensive, covering all the biopsychosocial aspects of the athlete. Decisions of when and how to return to sport are complex and should be team-based and preferably whole- model-based. The rate of return to competitive sport after ACL injury management is relatively low and not as commonly used to be thought of. Many factors are to be considered to optimize the return to competitive sport after ACL injury management.

The Relationship Between Active Coping Skills and Self-Reported Knee Function in Individuals with Anterior Cruciate Ligament Reconstruction.

Individuals with anterior cruciate ligament (ACL) injury commonly experience injury related stressors which can adversely impact subjective knee function after ACL reconstruction (ACLR). Due to the positive effect of active coping skills on perceived stressors, use of such strategies may influence clinical outcomes in individuals with ACLR, such as self-reported knee function. However, it is unknown whether active coping skills are associated with self-reported knee function in this population. Examine the relationship between active coping skills and self-reported knee function in individuals with ACLR. Cross-Sectional Study. Laboratory. Forty-five participants (34 females; age=20.0[3.3] years) 4-months to 5-years post-unilateral ACLR (time since ACLR=12.0[16.0] months). The Athlete Coping Skills Inventory (ACSI) Confidence and Achievement Motivation (ACSI Confid), Goal Setting/Mental Preparation (ACSI Goal/Prep), and Coping with Adversity (ACSI Coping) subscales were used to measure active coping skill facets. The Knee Injury and Osteoarthritis Outcome Score (KOOS) was used to measure self reported knee function across 5 subscales: pain (KOOS-Pain), symptoms (KOOS-Symptoms), activities of daily living (KOOS-ADL), quality of life (KOOS-QOL), and sports/recreation (KOOS-Sport). Partial Spearman's correlations were used to examine relationships between active coping skills and self-reported knee function after controlling for time since ACLR and age. Moderate positive correlations were observed between the ACSI Confid and KOOS Pain (r=0.493, P=0.001), ACSI Confid and KOOS-QOL (r=0.505, P<0.001), ACSI Confid and KOOS-Sport (r=0.422, P=0.007), and ACSI Goal/Prep and KOOS-Pain (r=0.441, P=0.004). Weak positive correlations were observed between the ACSI Goal/Prep and KOOS-ADL (r=0.373, P=0.018) and ACSI Goal/Prep and KOOS-QOL (r=0.374, P=0.017). Individuals with ACLR who exhibited greater active coping skill facets reported better knee-related function. Assessing active coping skills among individuals with ACLR and poor self-reported knee function may provide clinicians with insight into the role of coping in perceived function and potential treatment approaches.