Primary Anterior Cruciate Ligament Reconstruction Research Articles

Two-stage revision anterior cruciate ligament reconstruction reduces failure risk but leads to lesser clinical outcomes than single-stage revision after primary anterior cruciate ligament graft failure: a retrospective cohort study

BackgroundThere are no studies that compare the outcomes and complications of single-versus two-stage revision anterior cruciate ligament reconstruction (ACLR) after primary ACLR failure. This purpose of this study is to examine clinical and functional outcomes and complications associated with single and two-stage revision ACLR after primary ACLR failure.MethodsAll patients who underwent single or two-stage revision ACLR after primary ACLR failure between 2012 and 2021 with a minimum of a 2 year follow-up were included. Patients were excluded if they were not treated at our single academic institution, had inadequate follow-up, or had incomplete medical records. Revision intraoperative data, concomitant injuries, and complications were collected by chart review. Return to sport, numerical pain rating scale (NPRS) score, Knee injury and Osteoarthritis Outcome Score (KOOS), and Veteran Rands 12-item health survey (VR-12 scores) were collected.ResultsThe final analysis included 176 patients. A total of 147 (83.5%) had a single-stage revision ACLR (87 male, 60 female), and 29 (16.5%) had a two-stage revision ACLR (13 male, 16 female). Two-stage revision ACLR was significantly associated with anterior knee pain [odds ratio (OR) 4.36; 95% confidence interval (CI) 1.5 to 12.65; P = 0.007] but with lower failure rates (OR 0.12, 95% CI 0.02 to 0.9; P = 0.04). On multivariate analysis, a two-stage revision ACLR reduced the risk of graft failure by 85% (OR 0.15; 95% CI 0.02 to 1.17; P = 0.07). Two-stage revision ACLR was significantly associated with a lower KOOS pain score (OR −11.7; 95% CI −22.35 to −1.04; P = 0.031), KOOS symptoms score (OR −17.11; 95% CI −28.85 to −5.36; P = 0.004), KOOS Activities of Daily Living (ADL) score (OR −11.15; 95% CI −21.71 to −0.59; P = 0.039) and Veterans RAND 12-Item Health Survey (VR-12) physical component score (OR −9.99; 95% CI −15.77 to −4.22; P = 0.001).ConclusionsThe clinical outcomes and subjective patient scores significantly differed between the single-stage and two-stage revision ACLR after primary ACLR failure. Patients with a two-stage revision ACLR had a significantly reduced risk of revision graft failure but higher rates of postoperative anterior knee pain, lower pain scores, and lesser knee functional scores than single-stage revision patients.Study designRetrospective cohort study; level of evidence, 3

Diabetes and Untoward Outcomes after ACL Reconstruction

Background Diabetes affects approximately 536.6 million adults worldwide and 32.2 million in the United States. Prior studies across multiple specialties have reported the presence of diabetes is associated with adverse outcomes following surgical operations. While several studies have identified diabetes as a risk factor for adverse outcomes following ACL reconstruction (ACLR), literature evaluating the relationship between diabetes status and outcomes after ACLR is lacking. Purpose We aimed to study surgical outcomes following primary ACLR among patients with diabetes compared to those without diabetes. Study Design Retrospective Cohort Study Methods We conducted a cohort study using data from an integrated healthcare system’s ACLR registry. Patients aged ≥12 receiving a primary unilateral ACLR were included (2005–2020). Preoperative diabetes status was the exposure of interest. The two primary outcomes were revision surgery and ipsilateral reoperation following primary ACLR, modeled using multivariable Cox proportional hazards regression that followed patients until an adverse event or loss to follow up. We also examined hospital readmission within 90 days post-surgery, modeled using logistic regression. All models compared patients with diabetes to those without diabetes, adjusting for age, gender, race, smoking status, body mass index, American Society of Anesthesiologist’s score, comorbid conditions, education level, income level, exercise, and graft type. Results There were 18,797 primary ACLR in the study sample with 383 (2.0%) occurring in patients with diabetes. The diabetes group exercised about 90 minutes less per week than the non-diabetes group. In unadjusted bivariate descriptive analyses, patients with diabetes had a lower rate of revision surgery (1.6% vs. 3.6%, p = 0.037) but a higher rate of ipsilateral reoperation (10.7% vs. 8.0%, p = 0.051). The 90-day readmission rate was higher among patients with diabetes compared to those without diabetes (1.8% vs. 0.7%, p = 0.016). However, after adjusting for covariates, these associations were no longer statistically significant. Conclusion After controlling for patient characteristics and other risk factors, the presence of diabetes was not associated with a higher risk of adverse events following primary ACLR.

Young age and return to play increase the likelihood of subsequent ACL reconstruction in football players: Data from the Swedish National Knee Ligament Registry.

To compare football players who have undergone one anterior cruciate ligament (ACL) reconstruction (ACLR) with those who have undergone a subsequent ACLR (revision or contralateral) regarding (1) demographics, (2) football-related factors and (3) injury-specific data. Players who voluntarily completed a football-specific questionnaire available at the Swedish National Knee Ligament Registry website between April 2017 and September 2020 at the time of their primary ACL injury were included in the study. The questionnaire covered demographics, football-related activities and injury-specific factors. Subsequent ACLR registrations within 4 years of the primary ACLR were identified in December 2023. Data on game participation post-primary ACLR were retrieved from the Swedish Football Association's administrative system in September 2022. A total of 992 football players (66% men) were included, of whom 99 (10%) were registered for subsequent ACLRs. Univariable analysis showed that the following factors significantly increased the odds of a subsequent ACLR: female sex, younger age, a lower weight and body mass index, fewer years played, use of knee control exercises during warm-up, more likely to plan a return to football, more game participation registered following the primary ACLR, and shorter time between injury and ACLR. Multivariable logistic regression analysis indicated that the odds of undergoing subsequent ACLR decreased significantly with each additional year of age (odds ratio [OR], 0.87; 95% confidence interval [CI], 0.83‒0.92, p < 0.01). Players using knee control exercises during warm-up (OR, 1.71; 95% CI, 1.08‒2.72, p = 0.02), planning to return to football (OR, 2.74; 95% CI, 1.27‒5.91, p = 0.01), and participating in games after primary ACLR (OR, 1.81; 95% CI, 1.13‒2.91, p = 0.01) increased the odds of undergoing a subsequent ACLR. Younger age and returning to play after an ACLR significantly increase the likelihood of undergoing a subsequent ACLR in football players. Level IV.

Comparison of Synovialization and Clinical Outcomes between Anterior Cruciate Ligament Anteromedial Bundle Augmentation and Double-Bundle Anterior Cruciate Ligament Reconstruction.

This study aimed to compare clinical outcomes and second-look arthroscopic findings between double-bundle anterior cruciate ligament (ACL) reconstruction for complete ACL rupture and anteromedial (AM) bundle augmentation with preservation of the posterolateral (PL) bundle in isolated AM bundle rupture. Between 2014 and 2021, we retrospectively analyzed 95 ACL reconstructions with at least 2 years of follow-up. Patients undergoing primary ACL reconstruction from January 2014 to June 2021 were included in the study. Double-bundle ACL reconstruction (group 1) was performed in the cases involving male patients, high activity levels, age below 40 years, or when there was a patient preference for double-bundle reconstruction. In contrast, for partial ACL ruptures with an intact PL bundle confirmed on preoperative magnetic resonance imaging, AM augmentation was performed (group 2). Preoperative and final follow-up clinical outcomes, along with synovial coverage during second-look arthroscopy, were compared between group 1 (65 cases) and group 2 (30 cases). Statistical analysis included correlation coefficients between the groups. The Lysholm score, Tegner activity scores, and International Knee Documentation Committee (IKDC) knee evaluation form score at final follow-up were 81.8 (±5.5), 7.2 (±0.9), and 79.4 (±6.7), respectively, in group 1, and they were 88.0 (±6.4, p = 0.038), 7.9 (±0.5, p = 0.042), and 86.2 (±5.4, p = 0.081), respectively, in group 2. For group 1, the Lachman test (p = 0.093) and the pivot shift test (p = 0.176) at the final follow-up showed no laxity in 57 and 59 knees, and there was plus one laxity in 8 and 6 knees. For group 2, there were no laxity in 27 and 28 knees, and plus one laxity in 3 and 2 knees. Synovial coverage area percentages of the grafted tendon were 74.3 (±10.7) and 86.9 (±7.3, p = 0.002) in groups and group 2, respectively, with superior synovial coverage observed in group 2. The AM bundle augmentation with preservation of the PL bundle in ACL injury yielded better synovial coverage and clinical scores compared with double-bundle ACL reconstruction for complete ACL rupture.

Immunophenotyping of Synovial Tissue in Adolescents Undergoing ACL Reconstruction: What Is the Role of Synovial Inflammation in Arthrofibrosis?

Loss of motion and arthrofibrosis after anterior cruciate ligament (ACL) reconstruction (ACLR) can be devastating complications for athletes. The cellular and molecular pathogenesis of arthrofibrosis is poorly understood, limiting prevention and treatment options. Synovial inflammation may contribute to post-ACLR arthrofibrosis. Higher synovial immune cell infiltration and inflammatory/catabolic gene expression patterns at the time of ACLR would correlate with poorer motion-related outcomes. Case series; Level of evidence, 4. Patients aged 10 to 18 years undergoing primary ACLR were enrolled in a prospective pilot study, and synovial tissue biopsy specimens were obtained during ACLR. Flow cytometry and single-cell RNA sequencing explored synovial cell types/frequencies and gene expression. Principal component analysis was performed, followed by clustering which grouped patients into distinct immunophenotypes based on their synovial cell composition. Clinical follow-up data with knee range of motion (ROM), need for lysis of adhesions, and patient-reported outcome measures were collected and compared between immunophenotypes. Enrolled patients (n = 17) underwent ACLR at a median of 37 days after injury. Analysis revealed 3 distinct immunophenotypes. Type 1 consisted of patients with the longest time between injury and surgery and the lowest hematopoietic and T-cell infiltration. Types 2 and 3 had similar times between injury and surgery; type 2 had intermediate while type 3 had the highest hematopoietic and T-cell percentages. Type 3 was associated with worse ROM at 2 and 6 weeks postoperatively; T-cell prevalence and ROM were inversely correlated at those time points. The only patient requiring lysis of adhesions for arthrofibrosis had a type 3 immunophenotype. Synovial immune infiltration after ACL injury shows variability between patients that clusters into 3 immunophenotypes correlating with early ROM and the risk of arthrofibrosis. T-cell recruitment and infiltration were the strongest factors correlated with ROM outcomes and present an exciting venue for future research on post-ACLR arthrofibrosis.

Multiple secondary stabiliser injuries increase rotational instability in anterior cruciate ligament-deficient knees.

Medial meniscus ramp lesions (MMRLs), lateral meniscus posterior root tears (LMPRTs), and anterolateral complex injuries (ALCIs) are major secondary stabiliser injuries associated with anterior cruciate ligament (ACL) injuries. This study aimed to investigate the effect of the number of secondary stabiliser injuries on knee instability in ACL injuries. Patients who underwent primary ACL reconstruction between January 2017 and May 2023 were enroled in this study. Exclusion criteria encompassed patients with other ligament injuries, a history of contralateral knee injury, hyperextension, flexion contracture and meniscus injuries other than MMRL or LMPRT. Ultimately, 158 patients (mean age: 25.3 years; 81 males and 77 females) were included in this study, and the presence of MMRL, LMPRT and ALCI was investigated. Patients were categorised into four groups based on the number of ACL and secondary stabiliser injuries: single (isolated ACL injury), dual, triad and tetrad. Subsequently, the groups were compared regarding pivot shift grade, quantitative rotational instability measured using an inertial sensor, and anterior tibial translation (ATT). Secondary stabiliser injuries identified included ALCI 85 (53.8%), MMRL 58 (36.7%) and LMPRT 23 (14.6%). The distribution of patients in the single, dual, triad and tetrad groups was 45 (28.5%), 68 (43.0%), 37 (23.4%) and 8 (5.1%), respectively. High-grade pivot shifts were observed in 33.3% (15 out of 45) of the single group, 63.2% (43 out of 68) of the dual group, 67.6% (25 out of 37) of the triad group, and 100% (8 out of 8) of the tetrad group. Quantitative evaluations using the inertial sensor revealed significantly lower acceleration in the isolated ACL injury group compared to the other groups (p < 0.05). No significant difference was observed in ATT measurements (n.s.). The combination of secondary stabiliser injuries led to higher instability. Therefore, it is important to carefully diagnose these injuries and devise appropriate treatment plans, particularly in cases of high knee instability. Level III diagnostic.

Lower ACLR Failure Rates in Bone–Soft Tissue Versus Soft Tissue–Only Allografts in Adults: A Systematic Review and Meta-analysis

Background: While allografts are commonly used for anterior cruciate ligament reconstruction (ACLR), evidence to guide specific allograft selection is lacking. Purpose: To compare clinical and graft failure rates after ACLR using soft tissue–only allografts and bone–soft tissue allografts in adults. Study Design: Systematic review and meta-analysis; Level of evidence, 4. Methods: English-language studies with clinical outcome data on primary and revision ACLR in adults with nonirradiated soft tissue–only and bone–soft tissue grafts were identified in the search. Data extracted included allograft type, patient characteristics, follow-up time, and failure rates. The cumulative failure rate was defined as International Knee Documentation Committee grade C/D, graft retear, grade ≥2+ Lachman, grade ≥2+ pivot shift, and/or side-to-side KT-1000 laxity of &gt;5 mm. The graft rupture rate was defined solely by the proportion of patients who had a graft rupture. Meta-analyses using the inverse variance method were used to estimate the pooled rates with 95% CIs. Subgroup analysis was conducted to compare allograft types and determine whether age, sex, and follow-up time influenced the estimates. Results: A total of 14 studies met the inclusion criteria: 7 investigated bone–soft tissue allografts, 6 investigated soft tissue–only allografts, and 1 investigated both. The comparative study showed a difference in the cumulative failure rate between bone–patellar tendon–bone and soft tissue–only allografts. The pooled cumulative failure rates for bone–soft tissue and soft tissue–only allografts were 11% (95% CI, 7-17) and 20% (95% CI, 14-29), respectively ( P = .05). The pooled graft rupture rates for bone–soft tissue and soft tissue–only allografts were 6% (95% CI, 4-9) and 13% (95% CI, 7-23), respectively ( P = .07). Conclusion: The meta-analysis results showed that bone–soft tissue allografts have lower cumulative failure rates than soft tissue–only allografts. Bone–soft tissue allografts may be the preferred allograft choices for ACLR.

The Impact of Tibial Slope on Anterior Cruciate Ligament Reconstruction Outcomes – University Hospital Study

Anterior cruciate ligament (ACL) injuries are common knee injuries that often require surgical reconstruction to restore knee function and stability. Despite advances in surgical techniques, the failure rate for ACL reconstruction remains approximately 15%, emphasizing the need to understand factors contributing to suboptimal outcomes. One factor that has garnered attention is the tibial slope, particularly the posterior tibial slope (PTS), which may influence ACL injury and graft failure. Biomechanical studies suggest that an increased PTS can elevate anterior tibial translation, potentially increasing stress on the ACL and raising the risk of both primary ACL injury and graft failure. However, the clinical significance of tibial slope in ACL reconstruction outcomes remains debated. This retrospective study investigates whether an increased PTS is associated with a higher likelihood of revision surgery or poor surgical outcomes. A total of 152 patients who underwent primary ACL reconstruction or revision surgery between 2018 and 2022 with at least two years of follow-up were included. Tibial slope measurements were obtained from lateral tibial radiographs, and patients were categorized into three groups based on post-surgical outcomes: Group A (successful return to prior sport levels), Group B (stable knee without return to sport), and Group C (requiring revision surgery). The Mann-Whitney U test was used to compare tibial slope measurements across groups. No significant differences were found in tibial slope between the groups (p &gt; 0.05). Group A had a median tibial slope of 6.08°, Group B had 6.68°, and Group C had 5.85°. These findings suggest that tibial slope may not be a major factor influencing ACL reconstruction success or failure. Other factors, including surgical technique, rehabilitation, and patient-specific characteristics, may play more significant roles. Further research is needed to explore the relationship between tibial slope and ACL ...

Knee proprioception four months after anterior cruciate ligament reconstruction: impact of limb dominance, anterolateral procedure, and association with readiness to return to sport.

BackgroundKnee proprioception may be compromised after anterior cruciate ligament reconstruction (ACLR), but associated factors and impact remain unclear. This study evaluated knee proprioception 4 months after primary ACLR, compared with healthy controls, and explored the impacts of leg dominance, anterolateral procedures (AEAPs), and their association with psychological readiness to return to sports. MethodsThis prospective cohort study included 30 ACLR participants and 20 healthy controls. Isokinetic testing measured knee strength and proprioception, using passive joint position sense (JPS1: detection, JPS2: repositioning) and kinesthesia (threshold to detection of passive motion). At 8 months, ACLR participants completed the ACL-RSI scale to assess psychological readiness to return to sports. ResultsAt 4 months postoperative, kinesthesia was better in the operated limb than the non-operated limb (p= 0.008), but position sense did not differ significantly. There were no significant differences in kinesthesia or position sense between ACLR participants and controls. The operated limb had worse JPS2 if the ACLR was on the non-dominant side. Proprioception was unaffected by AEAPs, and only repositioning showed a moderate, non-significant correlation with ACL-RSI (r= -0.377). ConclusionAt 4 months post-ACLR, kinesthesia improved in the operated leg; dominance influenced position sense, highlighting the need for personalized rehabilitation.

Patient Perception of Return to Sport Level Following ACL Reconstruction with BTB Autograft is 85% or Less Upon Initial Return Back to Sports

Athletes undergoing anterior cruciate ligament reconstruction (ACLR) often aim to return to sport (RTS) at pre-injury levels. Our study examines perceived performance upon return to sport and return to occupation at one-year post ACLR in comparison to pre-injury levels. Patients were 15-43 years old, underwent primary ACLR with BTB-autograft (2016-2020), followed-up for at least one year, and completed pre- and post-operative surveys assessing athletic ability and perceived performance upon return to practice and competition. Knee pain during activity was evaluated alongside return to occupation when applicable. 85 patients met the inclusion criteria, revealing that patients averaged 4.9 weekly practice hours post-operatively compared to 8.6 hours pre-operatively. Cutting sport athletes returned to practice at 293.3 days (reporting 72.8% of their pre-injury level) and full competition at 315 days (82.7% of pre-injury level). Non-cutting athletes returned at 280.8 days (feeling 64.9% of pre-injury level) and competition at 311.7 days (reporting 85%). Out of 100 points (100 being most painful), patients ranked their knee pain as 10.8 for light jogging, 15.1 for high intensity jogging, and 16.4 with cutting moves. Return-to-work averaged 25.86 days for sedentary occupations (n=14), and 34.13 days for walking/standing occupational demands (n=8). Following ACLR using BTB autografts, patients return to cutting sports feeling less than 83% of their pre-injury level, while non-cutting sport patients feel less than 85% of their pre-injury level. Pre-injury perceived performance does not correlate with post-operative return to practice or competition. Sedentary occupations return to work sooner compared to those with consistent walking/standing occupational demands.

Greater Rotational Knee Laxity Observed at Second-Look Arthroscopy in Patients with Failed Meniscal Repair Performed at the Time of Anterior Cruciate Ligament Reconstruction.

To evaluate the healing of meniscal repair performed concomitantly with anterior cruciate ligament reconstruction (ACLR) using second-look arthroscopy, and the relationship between meniscal healing and knee laxity using quantitative evaluation under anesthesia. This retrospective study included patients who underwent primary double-bundle ACLR with meniscal repair between June 2016 and June 2021, with a two-year minimum follow-up. Meniscal healing was evaluated by second-look arthroscopy at least one year postoperatively, and knee laxity was measured under general anesthesia preoperatively, intraoperatively, and at second-look. Of 562 ACLR, 113 knees with 137 meniscal repairs were analyzed. Second-look arthroscopy classified 114 (83.2%) menisci as healed and 23 (16.8%) as failed. The side-to-side difference in anterior tibial translation (ATT) and the side-to-side ratio of tibial acceleration and external rotational angular velocity (ERAV) improved intraoperatively in both groups (ATT: 6.0--1.0 mm; P<.001, 6.0--1.0 mm; P<.001; acceleration: 5.1-1.2, 4.9-1.1; P<.001; ERAV: 3.6-1.3, 3.6-1.6; P<.001). There were no significant differences in ATT and patient-reported outcome measures (PROMs) including Lysholm scores and the Knee Injury and Osteoarthritis Outcome Score (KOOS), between groups. The proportion of patients achieving the minimal clinically important difference for Lysholm scores and KOOS did not differ significantly between the groups. However, at one year postoperatively, acceleration and ERAV were higher in the failed group than in the healed group (P<.001). Patients with failure of meniscal repair performed concomitant to ACLR demonstrated significantly greater rotational knee laxity at the time of second-look arthroscopy. These patients exhibited significantly higher pre-operative and post-operative pivot-shift grades than those who did not experience failure of meniscus repair. There were no significant differences in ATT and PROMs between the groups. Level Ⅲ, retrospective comparative study.

Combined Anterior Cruciate Ligament and Anterolateral Ligament Reconstruction Shows Superior Graft Remodeling, Maturation, and Stability Compared With Isolated Anterior Cruciate Ligament Reconstruction.

To compare graft remodeling, as measured by magnetic resonance imaging (MRI), and clinical outcomes between patients who underwent isolated anterior cruciate ligament reconstruction (ACLR) versus combined anterior cruciate ligament and anterolateral ligament reconstruction (ACLR + ALLR). A retrospective review was conducted on patients who underwent primary ACLR with quadruple hamstring grafts between January 2019 and March 2022, with a minimum follow-up period of 2 years. Patients were categorized into two groups based on the addition of ALLR with tibialis anterior allografts: an isolated ACLR group and an ACLR + ALLR group. Graft ligamentization was assessed using signal-to-noise quotient (SNQ) values obtained from postoperative MRI scans, with lower SNQ values indicating superior graft remodeling. Clinical outcomes were evaluated through knee stability tests (pivot-shift test, side-to-side laxity), functional outcomes, and graft retear rates. The minimal clinically important difference (MCID) for the clinical scores was calculated using the distribution-based method of a half standard deviation of the delta (difference between postoperative and baseline values). Regression analyses identified potential predictive factors for inferior ACL graft remodeling. A total of 122 patients in the isolated ACLR group and 54 in the ACLR + ALLR group were evaluated. The mean follow-up periods were similar between the groups (34.1 ± 7.4 months vs 36.4 ± 9.0 months; P = .755). The mean SNQ values were significantly lower in the ACLR + ALLR group compared to the isolated ACLR group (2.8 ± 1.6 vs 4.7 ± 3.5 mm, respectively; P = .001). Inferior ACL graft maturity was associated with an increased posterior tibial slope (P = .016), narrow notch width (P =.018), and concomitant medial meniscal lesion (P = .017). At the final evaluation, the ACLR + ALLR group demonstrated better rotational stability as indicated by the residual pivot-shift test (P = .005). No statistically significant differences were observed between the two groups in side-to-side laxity, functional outcomes, or graft retear rates. There were no differences in the percentage of patients achieving MCID for the International Knee Documentation Committee subjective score between the groups (P = .536). Combined ACLR and ALLR resulted in superior graft remodeling, demonstrated by a mean SNQ value that was 1.9 lower than in isolated ACLR, along with improved rotational stability. Level III, retrospective, nonrandomized, comparative therapeutic study.

Lack of association between revision ACL reconstruction and preoperative, intraoperative and post-operative factors at primary ACL reconstruction in children and adolescents.

To evaluate factors associated with revision anterior cruciate ligament reconstruction (ACLR) within 5 years of primary ACLR in children and adolescents. Children and adolescents (age <20 years at surgery) who underwent primary hamstring tendon ACLR at the Capio Artro Clinic, Stockholm, Sweden, between January 2005 and December 2018 were identified. Revision ACLR within 5 years of primary ACLR was captured in the Swedish National Knee Ligament Registry. Univariable and multivariable logistic regression analyses were used to evaluate the associations between revision ACLR and preoperative (age, sex, body mass index, time from injury to surgery, pre-injury Tegner activity level, medial collateral ligament injury, passive contralateral knee hyperextension [≤-5°]), intraoperative (medial meniscus and lateral meniscus [LM] resection or repair, cartilage injury and graft diameter) and post-operative (KT-1000 side-to-side anterior knee laxity, limb symmetry index for extension and flexion strength and single-leg-hop (SLH) test performance at 6 months) factors at primary ACLR. A total of 1888 patients (mean age: 16.0 ± 2.0, range: 8-19 years) who underwent primary ACLR were included. The overall incidence of revision ACLR within 5 years was 9.0% (170 out of 1888). Univariable analysis revealed that a time from injury to primary ACLR of <5 months (odds ratio [OR]: 2.27, 95% confidence interval [CI]: 1.61-2.35, p < 0.001) and LM resection (OR: 1.49, 95% CI: 1.00-2.20, p = 0.04) increased the odds of revision ACLR. Multivariable analysis showed that revision ACLR was significantly associated only with a time from injury to primary ACLR of <5 months (OR: 2.56, 95% CI: 1.72-3.70, p < 0.001). There was a lack of association between revision ACLR and preoperative, intraoperative and post-operative factors at primary ACLR in children and adolescents. A time from injury to primary ACLR of <5 months was the only factor associated with revision ACLR within 5 years. Level III.

Bone-patellar tendon-bone vs hamstring tendon autograft for anatomical anterior cruciate ligament reconstruction: outcomes at a mean follow-up of 8 years

Background. Anterior cruciate ligament (ACL) tear is a common ligament injury of the knee joint. Anterior cruciate ligament reconstruction (ACLR) using autografts or allografts is the standard of treatment for complete ACL tear. Anatomical tunnel positioning provides a better rotational as well as anteroposterior stability following ACLR. Nevertheless, a well-performed anatomical ACLR does fail due to various reasons. Graft selection may be one of the contributing factors. The aim of the study is to compare the outcome of anatomical anterior cruciate ligament reconstruction using bone-patellar tendon-bone autograft and hamstring tendon autograft at a mean follow-up of 8 years. Methods. The study enrolled 150 patients who underwent primary anatomical anterior cruciate ligament reconstruction using either bone-patellar tendon-bone (BPTB) or hamstring tendon (HT) autograft. Plain radiography was used to differentiate anatomical and nonanatomical reconstruction. Eighty patients (BPTB — 36, HT — 44) with anatomical reconstruction were then compared for their clinico-radiological outcome at a mean follow-up of 8 years. Results. The BPTB group showed better outcome over the HT group in terms of increased rotational and anteroposterior stability at long-term follow-up (pivot-shift test, p = 0.001; anterior drawer test, p = 0.001; the Lachman’s test, p = 0.001; radiological Lachman’s test, p = 0.001). There was no difference between the groups in terms of objective and subjective IKDC forms (p = 0.363 and p = 0.154, relatively), the Lysholm score (p = 0.894), anterior knee pain (p = 0.678), single-leg hop testing (p = 0.248) and osteoarthritic change (p = 0.550) at a mean follow-up of 8 years. Conclusions. Bone-patellar tendon-bone autograft resulted in superior clinical outcome over hamstring tendon autograft in terms of increased knee stability. No difference was observed between the grafts in other clinical outcomes and osteoarthritic change at a mean follow-up of 8 years.

Preoperative Physical Therapy Is Protective From Construct Failure in Anterior Cruciate Ligament Reconstruction.

Risk factors for anterior cruciate ligament reconstruction (ACLR) construct failure have been studied extensively. However, while some studies account for variables such as activity level, construct types, preoperative physical therapy, or patient demographics individually, comprehensive studies that control for all these factors simultaneously are scarce. By utilizing a robust multivariable analysis, the factors associated with an increased risk of ACLR construct failure can be determined. A single-center, retrospective cohort study was conducted, encompassing patients who underwent primary ACLR between January 2015 and December 2021. Level 3. Eligible patients were identified using the current procedural terminology code 29888. Datapoints collected included demographics, body mass index, injury setting, graft type, graft size, fixation type, concomitant ligamentous injuries, notchplasty, operating surgeon, preoperative physical therapy, and instances of construct failure. The prevalence of construct failure was analyzed using chi-square tests, comparing across all graft and fixation type combinations in ACLR procedures. A mixed-effects logistic regression model was utilized to account for the potential influence of all relevant variables on construct failure. Out of 1245 patients, the construct failure rate was 5.62% (n = 70), with >95% of patients having >2 years of retrospective follow-up (95% CI [4.34-6.90]), with a median failure time of 502.5 days (interquartile range [265.5-1033.8]). The mixed-effect logistic model identified preoperative physical therapy (odds ratio, 0.404, 95% CI [0.193-0.844]) as the only significant factor in possibly preventing construct failure. Contrary to conventional focus on graft and fixation types, this study emphasizes the protective role of preoperative physical therapy in reducing ACLR construct failure. Our findings suggest the integration of preoperative physical therapy in clinical practices to mitigate ACLR construct failure risk, warranting further exploration in future studies.

Males have higher psychological readiness to return to sports than females after anterior cruciate ligament reconstruction: a systematic review and meta-analysis

ObjectivesTo examine sex differences in psychological readiness to return to sport following anterior cruciate ligament (ACL) reconstruction as well as to determine whether males and females separately fulfilled cut-off values...

Short and proximalized interference screw fixation leads to tibial tunnel bone re-growth and better hamstring graft integration in ACL reconstruction.

The stability of the graft in the bony tunnels is of utmost importance in the anterior cruciate ligament reconstruction (ACLR) since it ensures safe healing at the tendon-bone interface. The hypothesis was that when a double tibial fixation was used in ACLR with a short graft of autologous hamstrings, tibial tunnel bone re-growth and better graft integration would be observed at short-term follow-up. The analysis included a cohort of 112 patients after a primary ACLR with hamstring tendons who underwent postoperative magnetic resonance imaging (MRI) 3.0-Tesla (3.0-T) 6 months after the surgery. The patients were divided into three groups based on the tibial fixation technique: 40 had a screw (group S), 35 had a screw and cortical button (group S + B) and 37 had a screw and anchor (group S + A). Two orthopaedic specialists independently evaluated the images, who measured the screw-free tunnel space, and assessed the presence of bone filling in the free tunnel. Furthermore, Ge's protocol was used to determine the graft healing in the tunnel. In 94 patients a screw-free tunnel space was detected, and a filling of the tunnel was reported in 80.85% of the cases (76 patients), being partial in 15.79% (12 patients) and complete in 84.21% (64 patients). Patients who presented better graft integration (Ge1) had significantly higher values of screw-free tunnel length compared to the other ones who had lower graft integration (Ge3)(p < 0.05). At 6 months postoperative MRI, tibial tunnel bone re-growth and graft-tunnel tibial integration after hamstring ACLR is significantly associated with the presence of free space between the anterior tibial cortex and the most distal portion of the interference screw, hence the use of a short and proximalized interference screw is suggested to restore bone stock after hamstring ACLR. Level IV retrospective comparative cohort study.

Cut-off value for the posterior tibial slope indicating the risk for retear of the anterior cruciate ligament.

The significance of the posterior tibial slope (PTS) has increasingly come into focus in anterior cruciate ligament (ACL) reconstruction being a risk factor for ACL graft failure. Nevertheless, inconsistent data on the critical value of the PTS exist. The purpose of this study was to define a cut-off value for the PTS in ACL surgery. In a retrospective cohort study, 350 revision ACL reconstructions (ACL-RR) with a failed ACL hamstring graft and 350 primary ACL reconstructions (ACL-R) were matched according to age, gender, concomitant injuries and graft characteristics and compared to a healthy control group. Using the proximal anatomic axis, lateral knee radiographs were evaluated for the PTS, interrater reliability was defined, ROC curves, Fischer's exact test and Baptista-Pike method were applied to define specificity and the odds ratio for a critical PTS value. Radiographic evaluation proved excellent interrater reliability (intraclass correlation coefficient 0.969). Evaluation of the PTS revealed 10.0 ± 2.2 (5-15) degrees in the ACL-RR group, 7.8 ± 1.8 (4.2-13) degrees in the ACL-R group and 6.6 ± 1.9 (3.6-12) degrees in the control group with significant differences between the groups (p < 0.001). A PTS value of 10.1 degrees proved a specificity of 98% for the prediction of an ACL graft failure and indicated an 11-fold risk for a retear of the ACL. A PTS exceeding 10.1 degrees carries an 11-fold risk for ACL graft failure and, therefore, should be considered in ACL reconstruction. These findings might serve as a cut-off value for the indication of a slope-reducing high tibial osteotomy in ACL surgery. Level III.

Association Between Pediatric International Knee Documentation Committee (Pedi-Ikdc) Score and Sagittal Knee Biomechanical Testing Following Anterior Cruciate Ligament Reconstruction

OBJECTIVE: to compare the Pediatric International Knee Documentation Committee (Pedi-IKDC) scores with sagittal knee kinematics and kinetics during the vertical drop jump test in pediatric athletes who had undergone primary unilateral anterior cruciate ligament reconstruction (ACLR), and determine if the two measures captured overlapping aspects of knee recovery. DESIGN: Retrospective Cohort Study METHODS: Seventy pediatric athletes who recently underwent ACLR completed biomechanical testing and the Pedi-IKDC survey. Limb symmetry for peak knee flexion angle (PKF), peak external knee flexion moment (PEKFM), and integral of power absorption (IPA) were evaluated and compared to Pedi-IKDC score using multivariate linear regressions controlling for time since surgery. Inter-knee symmetry was calculated using a limb symmetry index (LSI) by dividing the scores of the injured knee by the scores of the uninjured knee and multiplying by 100. RESULTS: There was a statistically significant positive relationship between Pedi-IKDC and LSI in PKF (R2=0.163, p=0.001) PEKFM (R2=0.067, p=0.033), and IPA (R2=0.087, p=0.014), indicating that higher Pedi-IKDC scores were associated with greater biomechanical symmetry when controlled for time. There were weak and significant positive relationships between time since surgery and PEKFM (R2=0.172, p&lt;0.001) and IPA (R2=0.255, p&lt;0.001) indicating improved biomechanical testing the further along from surgery, but there was no statistical significance between time since surgery and Pedi-IKDC or PKF. CONCLUSION: Pedi-IKDC and drop jump biomechanics were weakly related but mainly captured different aspects of recovery after ACLR. They can be considered as complementary tools when evaluating patients post-ACLR.

Oval Tunnel Shows Better Rotational Stability Than Round Tunnel in Anatomical Single-Bundle Anterior Cruciate Ligament Reconstruction: Biomechanical Study in a Porcine Model.

To compare knee laxity between the conventional round tunnel and oval tunnel techniques in primary anterior cruciate ligament (ACL) reconstruction in a porcine knee model. Twenty porcine knees were used for evaluating laxity in terms of anterior translation and anterolateral rotation. The study determined porcine knee kinematics on the Instron instruments under simulated Lachman (89 N anterior tibial load) at 15°, 30°, and 60° of flexion and a simulated pivot shift test (89 N anterior tibial load, 10 Nm valgus, and 4 Nm internal tibial torque) at 30° of flexion. Kinematics were recorded for intact (n = 10), ACL-deficient (n = 10), and conventional round (n = 10) or oval tunnel (n = 10) techniques. All measurements were repeated twice, and the average was used for comparison. Under the Lachman test, the conventional round tunnel and oval tunnel both showed significantly larger anterior tibial translation (ATT) at 30° and 60° compared to the intact knee (p < 0.05), but smaller ATT compared to the ACL-deficient knees (p < 0.05). However, there were no differences in ATT between the conventional round tunnel and oval tunnel techniques (p > 0.05). Under simulated pivot shift at 30° flexion, there was a significant difference between the conventional round tunnel and oval tunnel techniques (round vs. oval: 4.27 ± 0.87 mm vs. 3.52 ± 0.49 mm, p = 0.028). Both conventional round tunnel and oval tunnel techniques reduced ATT compared to ACL-deficient knees but failed to restore normal knee stability. However, the oval tunnel technique showed better rotational stability at 30° than the round tunnel technique. These findings suggest that the oval tunnel technique would be a reasonable option in anatomical single-bundle ACL reconstruction.