Anterior Cruciate Ligament Group Research Articles

Peracetic acid sterilized tendon and ligament allografts for knee reconstruction : For anterior cruciate ligament (ACL), posterior cruciate ligament (PCL) and complex knee surgery.

The use of allografts and autografts has been met with mixed views on whether allografts are asuitable alternative to autografts. We aimed to investigate if chemically sterilized allografts show similar rerupture rates to those reported in the literature for allografts and autografts in anterior (ACL) and posterior cruciate ligaments (PCL) and complex knee surgery. Retrospective data on knee reconstructions performed between 2011 and 2015 with tendon/ligamnet allografts sterilized with peracetic acid were collected in the form of aquestionnaire. The inclusion criteria of 2years for each patient were met by 38patients, representing 22ACL reconstructions, 5PCL reconstructions, 3OTHER surgeries, including the Larson technique and medial patellofemoral ligament (MPFL) reconstruction and 8COMPLEX surgeries. The main endpoints were rerupture and complication rate. Secondary endpoints included stability of the knee (Lachman test, Pivot shift test) and the range of motion. The rerupture rate was 7.9% (3grafts). Reruptures only occurred in the ACL group. No reruptures were observed in the PCL, OTHER and COMPLEX surgery groups. Stability improved significantly after surgery and the range of motion returned to values similar to that of healthy knees. Tendon allografts sterilized with peracetic acid show promising low rerupture rates and good clinical scores and the results are comparable to the literature on autografts and other allografts.

Progressive submaximal effort hamstring muscle endurance is reduced after reconstruction of the anterior cruciate ligament

BackgroundEndurance capability in the muscles controlling the knee is poorly understood post anterior cruciate ligament (ACL) reconstruction, despite many sporting activities requiring notable muscle endurance. The hamstring muscles, when active, provide important anatomical support to protect the reconstructed graft. In the absence of good hamstring endurance, fatigue may predispose individuals to re-injury. ObjectiveTo assess whether ACL reconstruction (ACLR) with a hamstring graft leads to reduced hamstring endurance 9–13 months post-surgery. Study designA cross-sectional inter-limb comparison study was undertaken with participants 9–13 months after an ACLR with a hamstring graft, and a group of age, sex, and activity-matched controls. There were 22 participants in each group. MethodSubmaximal hamstring endurance was measured using a progressive fatigue test on an isokinetic dynamometer at a joint angular velocity of 120°/second. The dependant variable was the maximum number of repetitions performed. Statistical comparisons were made across injured, uninjured and control group limbs. ResultsThere was a significant (p < 0.05) deficit in hamstring endurance observed between the injured leg (mean: 111 repetitions, SD 49) and uninjured leg (mean: 136 repetitions, SD 67) of the ACL group, but not between the uninjured and control group legs (mean: 124 repetitions, SD 50). ConclusionThe 18% deficit in submaximal hamstring endurance across the ACL-reconstructed individual's limbs is indicative of a notable loss in muscle performance at 9–13 months post-surgery. These results provide initial evidence for supporting further research examining the inclusion of hamstring endurance training in ACL rehabilitation programmes post-surgery.

How Subtalar Kinematics Affects Knee Laxity in Soccer Players After Anterior Cruciate Ligament Injury?

Purpose The goal of the current study was to ascertain whether there is an association between foot pronation and anterior cruciate ligament (ACL) injury in a group of elite professional soccer players. Methods Two groups of soccer players were studied, all of whom played in the Greek Super League. The ACL group included players who had suffered an ACL injury in the last 2 years. The non-ACL group was composed of players who had never suffered an ACL injury. We used a 3D baropodometric laser scanner to measure pronation or overpronation (navicular drop phenomenon) of the subtalar joint and how this affects the subtalar joint while standing. We assessed ACL laxity using the Genourob Rotab. Results ACL-injured patients, regardless of the mechanism of injury, exhibited greater navicular drop values than a randomly selected group of subjects with no history of ACL injury. Conclusion Greater knee joint laxity and subtalar pronation may be associated with an increased risk of ACL injury. Pronation of the foot appears to be a risk factor for ACL injury. These findings should be integrated into future studies to better define how neuromuscular control related to lower extremity biomechanics is associated with ACL injury.

Genetic factors and anterior cruciate ligament injury risk in professional football players: COL3A1 (rs1800255) and COL5A1 (rs12722) polymorphisms

This study was conducted to investigate the genotype and allele distributions of COL3A1 (rs1800255) and COL5A1 (rs12722) polymorphisms of professional footballers who have suffered at least 2 anterior cruciate ligament (ACL) injuries non-contact and professional footballers who have never had a ligament injury. The research group consists of 108 professional men's football players ACL group (n=45), Control group (n=63) with at least 10 years of football background. The results ACL and control groups were compared by Chi-square or Fischer’s exact test. There were no significant differences noted neither in terms of genotype distribution of COL3A1 (rs1800255) nor A-allele frequency distribution between control (CON) and ACL group. A highly significant difference in the allele distribution was noted for COL5A1 (rs12722) with the T-allele significantly less frequent in CON than ACL. The TT genotype compared to the C alleles (TC + CC) showed significant relationship between the TT genotype and ACL injury potential in the dominant model. However, it was not showing significance in the recessive (TT + TC vs. CC). In conclusion, it can be said that professional football players who have the COL5A1 rs12722 C allele have about 2 times lower risk of anterior cruciate ligament injury. In the COL3A1 rs1800255 polymorphism, there is no relationship between the groups in terms of genotypes and allele distribution.

Neuromuscular Characteristics of Unilateral and Bilateral Maximal Voluntary Isometric Contractions following ACL Reconstruction.

Despite the advancement of diagnostic surgical techniques in anterior cruciate ligament (ACL) reconstruction and rehabilitation protocols following ACL injury, only half of the athletes return to sports at a competitive level. A major concern is neuromechanical dysfunction, which occurs with injuries persisting in operated and non-operated legs following ACL rehabilitation. One of the criteria for a safe return to sports participation is based on the maximal voluntary isometric contraction (MVIC) performed unilaterally and a comparison between the 'healthy knee' and the 'operated knee'. The present study aimed to investigate MVIC in athletes following ACL rehabilitation during open kinetic chain exercise performed unilaterally and bilateral exercises. Twenty subjects participated in the present investigation: 10 male athletes of regional-national level (skiers, rugby, soccer, and volleyball players) who were previously operated on one knee and received a complete rehabilitation protocol (for 6-9 months) were included in the ACL group (age: 23.4 ± 2.11 years; stature: 182.0 ± 9.9 cm; body mass: 78.6 ± 9.9 kg; body mass index: 23.7 ± 1.9 kg/m2), and 10 healthy male athletes formed the control group (CG: age: 24.0 ± 3.4 years; stature: 180.3 ± 10.7 cm; body mass: 74.9 ± 13.5 kg; body mass index: 22.8 ± 2.7 kg/m2). MVICs synchronised with electromyographic (EMG) activity (recorded on the vastus lateralis, vastus medialis, and biceps femoris muscles) were performed during unilateral and bilateral exertions. The rate of force development (RFD) and co-activation index (CI) were also calculated. The differences in the MVIC and RFD between the two legs within each group were not significant (p > 0.05). Vastus lateralis EMG activity during MVIC and biceps femoris EMG activity during RFD were significantly higher in the operated leg than those in the non-operated leg when exertion was performed bilaterally (p < 0.05). The CI was higher in the operated leg than that in the non-operated leg when exertion was performed bilaterally (p < 0.05). Vice versa, vastus medialis EMG activity during RFD was significantly higher in the right leg than that in the left leg when exertion was performed bilaterally (p < 0.05) in the CG. MVICs performed bilaterally represent a reliability modality for highlighting neuromechanical asymmetries. This bilateral exercise should be included in the criteria for a safe return to sports following ACL reconstruction.

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

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

Poster 331: ACL Graft Tear or Contralateral ACL Tear: Which is Worse???

Objectives: Anterior cruciate ligament (ACL) graft tears and contralateral ACL tears are both relatively common following primary ACL reconstruction (ACLR). While some prior studies have combined these injuries as an outcome variable (“subsequent cruciate injury”), there is little prior work comparing the outcomes of these injuries. We hypothesize that patient reported outcome measures (PROMs) and activity level are lower following revision ACLR than following contralateral ACLR. Methods: From a prospective cohort study of 2333 patients who underwent primary, unilateral ACLR, 298 patients were identified who underwent revision ACLR or contralateral ACLR within 5 years of primary ACLR. Following exclusion of 11 patients who had both injuries, 256 patients were eligible for study inclusion, including 124 patients who underwent revision ACLR and 132 patients who underwent contralateral ACLR. Patients were contacted for follow-up at 6 years after the primary ACL reconstruction and PROMs were collected including subjective International Knee Documentation Committee (IKDC) score, Knee Osteoarthritis pain (KOOS-Pain) and knee-related quality of life (KOOS- QOL) subscales, and Marx activity level. Patient demographic and initial injury factors, surgical factors, and PROMs were compared between groups. Multiple regression models were used to determine whether side of subsequent surgery (revision versus contralateral ACLR) was a significant predictor of outcome. Results: Two hundred trenty-three of 256 patients (87%) were contacted and completed PROMs at 6 years following primary ACLR. The median time from primary ACLR to second ACL surgery was lower in the revision group (1.3 years) than the contralateral group (2.0 years, p &lt; 0.001). The revision group also demonstrated a lower incidence of partial lateral meniscectomy and was more likely to have received an allograft for the primary ACLR. There were no significant differences in age, sex, smoking status, pre- operative knee laxity, articular cartilage status at primary ACLR, medial meniscus status at primary ACLR, sport, or pre-operative PROMs between the two groups. At follow-up, the revision ACLR group demonstrated lower Marx activity level and PROMs than the contralateral injury group (Table 1). When controlling for the above factors, the revision ACL group demonstrated a 7.8 point lower IKDC (p&lt;0.001), a 3.2 point lower KOOS-pain (p=0.012), a 10.4 point lower KOOS-QOL (p&lt;0.001), and 2.0 point lower Marx score (p=0.002) than the contralateral ACLR group. Conclusions: Patients who undergo revision ACL R demonstrate with poorer PROMs and lower activity level than those who undergo subsequent revision ACLR. [Table: see text]

Comparison of Physical Therapy Utilization and Motion-Related Re-operations Between Isolated Anterior Cruciate Ligament and Multi-Ligament Knee Injuries.

The increased prevalence of postoperative arthrofibrosis after multi-ligament knee injuries (MLKI) compared to isolated anterior cruciate ligament (ACL) injuries has been proposed to be due, in part, to patient factors limiting physical therapy utilization. The purpose of this study was to compare demographic factors, pre- and postoperative physical therapy utilization, and the need for motion-restoring surgery between MLKI and ACL-injured patients. Using the PearlDiver Mariner 151 database, two cohorts matched by age and sex were identified using current procedural terminology (CPT) codes and included those age 16 or greater that underwent isolated ACL (n=3801) vs. MLKI reconstruction (n=3801). The number of pre- and postoperative physical therapy visits was recorded, as was the need for motion-restoring surgery (arthroscopic lysis of adhesions or manipulation under anesthesia). Demographic factors, physical therapy utilization, and the prevalence of motion-restoring surgery were compared between the MLKI and ACL groups using t-tests or chi-square tests, as appropriate. A significantly greater proportion of those with MLKI underwent subsequent motion-restoring surgery (MLKI=412/3081 (13.4%) vs. ACL=84/3081 (2.7%), p<0.001; odds ratio = 5.5 (95% CI: 4.3, 7.0), p<0.0001). Following surgery, less than half of those with MLKI that underwent subsequent motion-restoring surgery attended physical therapy, which was significantly lower than those who did not require motion-restoring surgery (p<0.0001). The prevalence of motion-restoring surgery was significantly greater after MLKI when compared to an isolated ACL injury. While the etiology of arthrofibrosis after MLKI is likely complex, the current results suggest that demographic factors and physical therapy utilization are not solely responsible for the increased risk of arthrofibrosis after MLKI.

Bone Morphological Characteristics as Risk Factors for Anterior Cruciate Ligament Injury: Comparison Between Contact and Noncontact Injury

Background: Altered bone morphologies are considered risk factors for noncontact anterior cruciate ligament (ACL) injuries. Purpose/Hypothesis: This study aimed to investigate bone morphological characteristics as risk factors for ACL tears in contact injuries and compare these factors with those for noncontact ACL injuries. We hypothesized that altered bone morphologies would also be risk factors for contact ACL injury. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Enrolled were patients who underwent primary ACL reconstructions between January 2000 and December 2021 within 6 weeks after injury. Patients in the ACL group were classified according to injury mechanism (contact vs noncontact). During the same period, a control group of patients matched by age, height, and body mass index to the ACL group was selected. The lateral femoral condylar ratio (LFCR), notch width index (NWI), and lateral posterior tibial slope (PTS) were measured. Measured parameters were compared between the control, contact, and noncontact groups using analysis of variance. Results: There were 86 patients in the control group, 102 patients in the contact ACL group, and 105 patients in the noncontact ACL group. The demographic characteristics of the 3 groups did not differ significantly. The contact group had significantly higher LFCRs and lower NWIs compared with the control group ( P &lt; .001 and P = .001, respectively). The noncontact group had significantly higher LFCRs and PTSs and lower NWIs compared with the control group ( P = .031; P &lt; .001; and P &lt; .001, respectively). The noncontact group had significantly higher PTSs and lower NWIs compared with the contact group ( P = .003 and P =.014, respectively). In the contact group, the LFCR, PTS, and NWI were significant risk factors for ACL tears (odds ratio [OR], 1.25 [ P &lt; .001]; OR, 1.16 [ P = .008]; and OR, 1.27 [ P = .001], respectively), and in the noncontact group, the PTS and NWI were significant risk factors for ACL tears (OR, 1.20 [ P &lt; .001]; OR, 1.59 [ P &lt; .001], respectively). Conclusion: Altered bone morphological characteristics of the knee were found to be risk factors for ACL tears in contact injuries as well as noncontact injuries. Altered morphology has a more significant effect in noncontact ACL injuries.

Leveraging Insurance Claims Data to Identify Risk Factors for Posttraumatic Osteoarthritis After Multiligament Knee Reconstruction

Background: The incidence of subsequent posttraumatic osteoarthritis (OA) diagnosis after surgery and the associated risk factors have been well reported after single-ligament anterior cruciate ligament (ACL) reconstruction; however, to date, the incidence of posttraumatic OA for those who have experienced multiligament knee injury (MLKI) has been reported only in relatively small, single-center studies. Purpose: To compare the incidence of OA diagnoses between patients with ACL injury versus patients with MLKI and to identify risk factors for OA diagnosis after MLKI. Study Design: Cohort study; Level of evidence, 3. Methods: This study used the PearlDiver Mariner database, which contains insurance claims information on >151 million orthopaedic patients. We identified 2 cohorts for this study by using Current Procedural Terminology codes. The cohorts included patients between the ages of 16 and 60 who underwent either isolated ACL reconstruction (n = 114,282) or MLKI reconstruction (n = 3325) between July 1, 2010, and August 30, 2016. MLKI reconstruction was operationally defined as ACL reconstruction plus concurrent surgical treatment of ≥1 additional ligaments. Demographic factors, concomitant meniscal and cartilage procedures, and subsequent reoperation to restore motion were recorded, as was the incidence of knee OA diagnosis within 5 years of the index surgical procedure. OA incidence and demographic and surgical factors were compared (1) between ACL and MLKI groups and (2) between patients with MLKI either with or without OA diagnosis. Results: A significantly greater proportion of patients with MLKI were diagnosed with knee OA within 5 years of surgery (MLKI = 299/3325 [9.0%] vs ACL = 6955/114,282 [6.1%]; P < .0001) (odds ratio [OR], 1.52; 95% CI, 1.35-1.72; P < .001). Factors associated with increased odds of OA diagnosis after MLKI included age ≥30 years (OR, 5.90), reoperation to restore motion (OR, 2.54), obesity (OR, 1.96), mood disorder diagnoses (OR, 1.85), partial meniscectomy (OR, 1.85), and tobacco use (OR, 1.72). Concomitant meniscal repair was protective against OA diagnosis (OR, 0.06). Conclusion: OA incidence was greater after MLKI reconstruction than after isolated ACL reconstruction. Potentially modifiable risk factors for OA after MLKI were identified and include obesity, tobacco use, depression, and the need for motion-restoring surgery.

Small Hamstring Tendon Graft for Anterior Cruciate Ligament Reconstruction Combined With Anterolateral Ligament Reconstruction Results in the Same Failure Rate as Larger Hamstring Tendon Graft Reconstruction Alone

To compare patients undergoing anterior cruciate ligament (ACL) reconstruction with hamstring grafts 7 mm or less in diameter combined with anterolateral ligament (ALL) reconstruction versus isolated ACL reconstruction with grafts greater than 7 mm in diameter. We retrospectively evaluated the descriptive data and clinical outcomes of patients who underwent primary ACL reconstruction with hamstring grafts from June 2013 to January 2020 and had a minimum follow-up period of 2 years. Patients with quadrupled or quintupled semitendinosus and gracilis autograft 7 mm or less in diameter combined with single-strand ALL reconstruction (ACL-ALL group) were matched in a 1:2 propensity ratio to patients who underwent isolated single-bundle ACL reconstruction with hamstring grafts greater than 7 mm (ACL group). We identified 30 patients in our database who met the criteria for the ACL-ALL group. The patients in this group were matched to 60 patients comprising the ACL group. Both groups were similar regarding all preoperative matched and unmatched variables. The mean ACL graft diameter was 6.8 ± 0.4 mm in the ACL-ALL group and 8.6 ± 0.6 mm in the ACL group (P < .001). The ACL-ALL group presented 1 failure (3.3%), and the ACL group presented 3 failures (5%) (P= .717). Postoperative KT-1000 measurements were similar between the groups (2.1 ± 1.1 mm vs 1.9 ± 1.2 mm, P= .114), as were postoperative pivot-shift grades (P= .652). Subjective International Knee Documentation Committee scores and Lysholm scores did not present any differences between the groups (P= .058 and P= .280, respectively). Patients who undergo combined ACL-ALL reconstruction with an ACL graft diameter of 7 mm or less can achieve similar results to patients who undergo isolated ACL reconstruction with a graft diameter greater than 7 mm. An associated ALL reconstruction can be performed to increase knee stability in patients with small-diameter hamstring grafts. Level III, retrospective, comparative therapeutic trial.

Knee anatomic geometry accurately predicts risk of anterior cruciate ligament rupture.

Certain anatomical characteristics of the knee have potential relationships with the risk of anterior cruciate ligament (ACL) rupture. There remains a need for stronger evidence using arthroscopy as well as radiological imaging to accurately clarify these relationships. To compare the anatomic geometry of the knee joint between patients with and without ACL ruptures. Case-controlled study of patients with arthroscopically confirmed ACL ruptures (ACL group) compared to patients with arthroscopically confirmed normal ACLs (control group). Magnetic resonance imaging scans were assessed for a total of 14 quantitative radiological variables including medial and lateral tibial slope angles (bone and cartilage measurements), meniscal height, femoral width, intercondylar notch width and tibial depth. A total of 105 patients were included in the study, 55 in the ACL group and 50 in the control group. There was a significant difference (P < 0.05) of most of the radiological measurements between the two groups. There was also a significant difference (P < 0.05) when comparing the variables between sexes. Multiple logistic regression analysis produced a mathematical model utilizing all the radiological measurements with 92.6% classification accuracy in predicating an ACL rupture with the medial tibial slope angle being the strongest predicator variable (odds ratio = 8.97, P = 0.011). Greater postero-inferior directed slope measurements of bone and cartilage in both the lateral and medial compartments with a narrower intercondylar notch width increase the risk of ACL rupture. Mathematical modelling can accurately predict the risk of ACL rupture.

Composite Score of Readiness (CSR) as a Data Reduction Technique for Monitoring the RTS Process in Footballers following ACL Reconstruction

In recent years, many studies on the safe return to sport (RTS) have been published, but there are still no clear and validated guidelines. After ACL reconstruction between limbs, asymmetry of muscle strength affects knee mechanics during walking and running, and asymmetrical joint kinematics and kinetics are considered as a strong risk factor of musculoskeletal injury. Therefore, proper diagnosis of any motor deficits remaining after ACL reconstruction seems particularly important. The aim of this study was to analyze how many tests should be included in the RTS test battery and which of them are most indicative for functional deficits related to anterior cruciate ligament (ACL) reconstruction. Sixty-five male football players (age 18–25 years) were divided into three groups: ACL group—after ACL rupture and reconstruction, mild injury group—post mild lower limb injuries, and the control group—without injuries. They performed five tests: Functional Movement Screen, Tuck Jump Assessment, Y-balance Test, Hop Test for Distance, and Isokinetic Test. The Composite Score of Readiness (CSR) index was calculated and expressed as the sum of z-scores. The multiple regression model for all tests was calculated, and then redundant variables were excluded. We observed that all tests significantly influenced the final CSR index. The Y-balance Test, Tuck Jump Assessment, and Isokinetic Test for knee flexion influenced the final CSR index the most, which means that these tests are greatly indicative of functional deficits related to ACL reconstruction. The strength of the extensor (quadriceps) muscle and the quadriceps/hamstring ratio appeared to be non-sensitive for testing functional deficits related to ACL reconstruction. If the test battery includes 4–5 tests, it better differentiates the athletes following ACL reconstruction from those after mild injuries, even if they all were cleared to play.

Does posterior tibial slope laterality exist? A matched cohort study between ACL-injured and non-injured knees

PurposeThe purpose of this study is to examine 1) the degree and frequency of laterality in posterior tibial slope (PTS) with control and anterior cruciate ligament (ACL) injury groups and 2) the laterality of PTS between sides of injury and dominant legs in patients with primary ACL injuries.MethodsA total of 187 consecutive patients with clinically diagnosed noncontact ACL injuries and an age- and sex-matched 1:1 control group were identified. PTS was measured using three different methods (aPTS = anterior PTS, mPTS = middle PTS, pPTS = posterior PTS) on a lateral knee radiograph. PTS of the left and right sides were compared between the patients in the control and ACL-injured groups, and between the injured and non-injured and dominant and non-dominant legs among the patients in the ACL-injured group. The patients with a difference in PTS of ≥ 3° in mPTS were selected. The percentages were compared between left and right between and among both groups, and between the injured and non-injured, and non-dominant and dominant leg, for the ACL group. Multiple regression analysis was performed to analyze the factors influencing the degree of mPTS.ResultsBoth control (Right vs Left: aPTS; 9.0 ± 2.5 vs 10.5 ± 3.0, mPTS; 6.6 ± 2.3 vs 8.1 ± 2.7, pPTS; 4.0 ± 2.4 vs 5.6 ± 2.8, respectively, p < 0.01) and ACL injury groups (Right vs Left: aPTS; 10.6 ± 3.0 vs 12.6 ± 2.9, mPTS; 7.6 ± 2.6 vs 9.5 ± 2.6, pPTS; 5.9 ± 3.0 vs 8.0 ± 3.0, respectively, p < 0.01) had a significantly greater PTS on the left than on the right side, and the ACL group had a significantly greater PTS than the control group on both the left and right sides. In the ACL group, PTS was greater on the injured and the non-dominant leg than on the non-injured and the dominant leg. The percentage of patients with a PTS difference of ≥ 3° was significantly greater on the left, injured, and non-dominant leg (95.3% vs 4.7%, 73.8% vs 26.2%, 86.1% vs 13.9%, respectively, p < 0.01). Only the left leg had a significant influence on PTS in the multivariate analysis.ConclusionThere was laterality in PTS within control and ACL injury groups, and this information is of benefit for effective treatment of ACL injuries.Level of evidenceLevel III.

Characterization of microRNA Levels in Synovial Fluid from Knee Osteoarthritis and Anterior Cruciate Ligament Tears.

This study investigated modifications of microRNA expression profiles in knee synovial fluid of patients with osteoarthritis (OA) and rupture of the anterior cruciate ligament (ACL). Twelve microRNAs (26a-5p, 27a-3p, let7a-5p, 140-5p, 146-5p, 155-5p, 16-5p,186-5p, 199a-3p, 210-3p, 205-5p, and 30b-5p) were measured by real-time quantitative polymerase chain reaction (RT-qPCR) in synovial fluids obtained from 30 patients with ACL tear and 18 patients with knee OA. These 12 miRNAs were chosen on the basis of their involvement in pathological processes of bone and cartilage. Our results show that miR-26a-5p, miR-186-5p, and miR-30b-5p were expressed in the majority of OA and ACL tear samples, whereas miR-199a-3p, miR-210-3p, and miR-205-5p were detectable only in a few samples. Interestingly, miR-140-5p was expressed in only one sample of thirty in the ACL tear group. miR-140-5p has been proposed to modulate two genes (BGN and COL5A1100) that are involved in ligamentous homeostasis; their altered expression could be linked with ACL rupture susceptibility. The expression of miR-30b-5p was higher in OA and chronic ACL groups compared to acute ACL samples. We provide evidence that specific miRNAs could be detected not only in synovial fluid of patients with OA, but also in post-traumatic ACL tears.

Evidence of ACL healing on MRI following ACL rupture treated with rehabilitation alone may be associated with better patient-reported outcomes: a secondary analysis from the KANON trial

ObjectivesEvaluate the natural course of anterior cruciate ligament (ACL) healing on MRI within 5 years of acute ACL rupture and compare 2-year and 5-year outcomes based on healing status and...

Benefits of Implementing an Enhanced Recovery After Surgery Protocol in Ambulatory Surgery.

Enhanced recovery after surgery (ERAS) protocols in orthopaedic surgery have garnered significant focus due to their ability to control pain adequately in the immediate postoperative window, allowing for earlier mobilization, shorter hospital stays, and fewer complications. Virginia Commonwealth University created a multimodal pain management approach in which patients receive a preoperative femoral nerve block followed by periarticular intraoperative local injection anesthesia consisting of bupivacaine, ketamine, and ketorolac. We hypothesized that implementation of the ERAS protocol will decrease postoperative pain scores, decrease recovery time in the postanesthesia care unit (PACU), and decrease opioid use in anterior cruciate ligament (ACL) reconstruction. Cohort study; Level of evidence, 3. Two patient cohorts were involved: before ERAS implementation (pre-ERAS) and after (post-ERAS). Patients with ACL reconstruction only and patients with ACL reconstruction with meniscal repair were analyzed separately. Post-ERAS patients received an intraoperative periarticular injection of bupivacaine, ketamine, and ketorolac and a postoperative multimodal pain regimen. Outcomes included time spent in the PACU, short-term and long-term opioid consumption, and pain score at discharge from the PACU. Compared with pre-ERAS patients, post-ERAS patients had decreased pain (2.1 vs 0.84 out of 10, respectively), spent less time in the PACU (79.4 vs 62.8 minutes, respectively), and had less opioid consumption in the immediate postoperative period (4.55 vs 2.26 total morphine milligram equivalents [MMEs], respectively) (P < .001 for all). After ERAS implementation, long-term MME use decreased from 410 to 321 between 0 and 2 weeks postoperatively, 92.6 to 1.69 between 2 and 6 weeks, and 494.5 to 323 between 0 and 6 weeks (P < .001 for all). All domains showed significant improvements for both the ACL and the ACL plus meniscal repair cohorts, with the exception of pain at discharge in the ACL plus meniscal repair group. The study findings suggest that an enhanced recovery pathways protocol that includes a standardized intraoperative periarticular bupivacaine, ketamine, and ketorolac injection improves pain scores in the immediate postoperative window, decreases opioid consumption, and reduces recovery time in the PACU for patients undergoing ACL reconstruction.

No Difference Unicompartmental Knee Arthroplasty for Medial Knee Osteoarthritis With or Without Anterior Cruciate Ligament Deficiency: A Systematic Review and Meta-analysis

BackgroundA functional intact anterior cruciate ligament (ACLI) is considered to be a prerequisite for unicompartmental knee arthroplasty (UKA). However, UKA has been shown to have good clinical efficacy in ACL-deficient (ACLD) knees at 3 to 10 years follow-up. Therefore, the role of ACLD in UKA remains controversial, and more evidence is needed to clarify the role of ACLD in UKA. MethodsPubMed, the Web of Science, EMBASE, and Cochrane Central were queried for articles comparing the results of the ACLD and ACLI groups after UKA. Outcomes of interest included the Tegner Activity Scale, the Oxford Knee Score (OKS), postoperative slope of the implant (PSI), the Knee Injury and Osteoarthritis Outcomes Score (KOOS), the Lysholm score, and revision rate. There were eight studies included. The mean age was 66 years (range 49 to 87 year old) and the mean follow-up time was 6.9 years (range 1.3 to 16.6 years). There was baseline comparability regarding mean age, duration of follow-up, and body mass index (P > .5) between the ACLD and ACLI groups. ResultsThe ACLD and ACLI groups had improved postoperative functional indicators, and that postoperative revision rate (mean difference [MD], 1.24; 95% confidence interval [CI], 0.75 to 2.04; P = .4), Tegner score (MD, −0.1; 95% CI, −0.26 to 0.05; P = .19), and Lysholm score (95% CI, −2.46 to 7.32; P = .33) were similar between the groups, with no significant differences; however, the ACLD groups had significantly better KOOS Activities of Daily Living scores, with a significant difference (MD, 4.53; 95% CI, 1.75 to 7.3; P = .001). Also, there were no significant differences between two groups in the PSI, OKS, KOOS. ConclusionACL deficiency is not always a contraindication for UKA. With correct patient selection, UKA could be considered for medial knee osteoarthritis with ACL deficiency without antero-posterior instability, especially these people over 60 years of age.

The posterior cruciate ligament-posterior femoral cortex angle: a reliable and accurate MRI method to quantify the buckling phenomenon of the PCL in ACL-deficient knees.

The aim was to validate a new MRI method to measure the buckling phenomenon of the PCL, representative of anterior tibial translation, by comparing its reliability and accuracy to identify anterior cruciate ligament (ACL)-deficient knees with existing methods. Patients were selected retrospectively and separated into a group of primary ACL injuries and ACL-intact knees. Exclusion criteria were: skeletal immaturity, PCL or a concomitant collateral ligament injury, signs of osteoarthritis (> 1 Kellgren and Lawrence score), tibial plateau fracture, previous ACL reconstruction or displaced meniscal bucket handle tear. The assessment of the curvature of the anterolateral bundle of the PCL was performed on T2 sagittal MRI slices according to 3 methods: (1) the PCL angle (PCLA), (2) the PCL inclination angle (PCLIA) and (3) a new method: the PCL-posterior cortex angle (PCL-PCA), representing the angle between the vertical part of the PCL-ALB and the posterior diaphyseal cortex of the femur. For each method, the inter- and intra-observer reliability was measured. The ability to discriminate both ACL-deficient and ACL-intact knees was evaluated using ROC curves. Twenty-four patients were included in each group. Intra-observer reliability was excellent for all 3 methods (ICCs > 0.90). Inter-observer reliability was excellent for the PCL-PCA (ICC > 0.90) and good for the PCLA and the PCLIA (ICCs between 0.75 and 0.90). The PCL-PCA had the highest precision (lowest standard error of measurement: 2.7°). It yielded an excellent discrimination between the ACL and CTL groups (AUC 0.80 [0.67-0.93]) with the highest sensitivity (71% [52.8-89.2]) and specificity (88% [75-100]) for a positive threshold when the angle was ≤ 22.7°. The PCLA and PCLIA methods led to acceptable discrimination and lower sensitivities and specificities (PCLA: AUC 0.71, sensitivity 63%, specificity 79%, threshold ≤ 117.9°; PCLIA: AUC 0.62, sensitivity 50%, specificity 83%, threshold ≤ 21.4°). In comparison with previously described methods, the PCL-PCA was the most reliable and accurate method to measure the PCL buckling phenomenon on MRI in anterior cruciate ligament (ACL)-deficient knees. It offers an easy and objective method for the follow-up of ACL-injured patients and can therefore be recommended for routine use. IV.

Different patient and activity-related characteristics result in different injury profiles for patients with anterior cruciate ligament and posterior cruciate ligament injuries

PurposeTo compare patient characteristics including patient sex, age, body mass index (BMI), activities at the time of injury and injury profiles in patients with anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) injuries.MethodsData were obtained from the Swedish National Knee Ligament Registry. Two study groups were created: (1) index ACL reconstruction (ACL group) and (2) index PCL reconstruction (PCL group). Between-group differences were investigated using Fisher’s exact test and Fisher’s non-parametric permutation test for dichotomous variables and continuous variables, respectively.ResultsOf 39,010 patients, 38,904 were ACL injuries. A larger proportion of patients with combined injuries to the PCL, meniscus and cartilage were female, aged > 25 years and with a BMI of > 35 kg/m2 compared with patients with combined injuries to the ACL, meniscus and cartilage. An isolated ACL injury was more commonly found in males, while all other injury profiles of ACL, including combined injuries with meniscus, cartilage and collateral ligament injuries, were more frequently observed in females. The PCL injuries were sustained either during pivoting sports, non-pivoting sports or were traffic-related.ConclusionDifferent patient characteristics (BMI, age and sex), and activities at the time of injury (sport- versus traffic-related activities), resulted in distinct injury profiles for the ACL and PCL groups. These findings provide valuable information of the way specific injury patterns of cruciate ligament injuries occur, and subsequently may help clinicians with the diagnostic process of ACL and PCL injuries.Level of evidenceIII.