This study aimed to compare functional outcomes sequentially up to 1 year after combined anterior cruciate ligament reconstruction (ACLR) and anterolateral ligament reconstruction (ALLR) and isolated ...ACLR. Fifty patients who underwent ACLR with versus without ALLR were analyzed at four different time points (preoperatively and 3, 6, and 12 months postoperatively). For the functional outcomes, muscle strength and acceleration time (AT) were measured using an isokinetic dynamometer. Proprioception was evaluated using joint position sense and dynamic postural stability. Patient-reported outcomes were measured using the Tampa Scale for Kinesiophobia (TSK-11) scores. Functional performance was assessed using single-leg hop distance (SLHD) and Limb Symmetry Index. In the operated knees, quadriceps (at 6 months postoperatively, p = 0.003) and hamstring (at 6 and 12 months postoperatively, p < 0.001) strength were significantly higher in the combined ACLR and ALLR group than the isolated ACLR group. The TSK-11 (at 6 and 12 months postoperatively, p < 0.001) was significantly lower in the combined ACLR and ALLR group than the isolated ACLR group. SLHD was significantly higher in the combined ACLR and ALLR group than the isolated ACLR group (at 6 months, p = 0.022 and at 12 months, p = 0.024). The addition of ALLR to primary ACLR yielded better muscle performance, fear of movement, and functional performance than isolated ACLR.
Background
The factors that contribute to the abnormal knee kinematics after anterior cruciate ligament (ACL) injury and ACL reconstruction remain unclear. Bone shape has been implicated in the ...development of hip and knee osteoarthritis, although there is little knowledge about the effects of bone shape on knee kinematics after ACL injury and after ACL reconstruction.
Questions/questions
(1) What is the relationship between bony morphology with alterations in knee kinematics after ACL injury? (2) Are baseline bone shape features related to abnormal knee kinematics at 12 months after ACL reconstruction?
Methods
Thirty-eight patients (29 ± 8 years, 21 men) were prospectively followed after acute ACL injury and before ligamentous reconstruction. Patients were excluded if there was a history of prior knee ligamentous injury, a history of inflammatory arthritis, associated meniscal tears that would require repair, or any prior knee surgery on either the injured or contralateral side. In total, 54 patients were recruited with 42 (78%) patients completing 1-year followup and four patients excluded as a result of incomplete or unusable imaging data. MR images were obtained for the bilateral knees at two time points 1 year apart for both the injured (after injury but before reconstruction and 1 year after reconstruction) and contralateral uninjured knees. Kinematic MRI was performed with the knee loaded with 25% of total body weight, and static images were obtained in full extension and in 30° of flexion. The side-to-side difference (SSD) between tibial position in the extended and flexed positions was determined for each patient. Twenty shape features, referred to as modes, for the tibia and femur each were extracted independently from presurgery scans with the principal component analysis-based statistical shape modeling algorithm. Spearman rank correlations were used to evaluate the relationship between the SSD in tibial position and bone shape features with significance defined as p < 0.05. Each of the shape features (referred to as the bone and mode number such as Femur 18 for the 18th unique femoral bone shape) associated with differences in tibial position was then investigated by modeling the mean shape ± 3 SDs.
Results
Two of the 20 specific femur bone shape features (Femur 10, Femur 18) and two of the 20 specific tibial bone shape features (Tibia 19, Tibia 20) were associated with an increasingly anterior SSD in the tibial position for the patients with ACL injury before surgical treatment. The shape features described by these modes include the superoinferior height of the medial femoral condyle (Femur 18; ρ = 0.33, p = 0.040); the length of the anterior aspect of the lateral tibial plateau (Tibia 20; ρ = −0.35, p = 0.034); the sphericity of the medial femoral condyle (Femur 10; ρ = −0.52, p < 0.001); and tibial slope (Tibia 19; ρ = 0.34; p = 0.036). One year after surgical treatment, there were two of 20 femoral shape features that were associated with SSD in the tibial position in extension (Femur 10, Femur 18), one of 20 femoral shape features associated with SSD in the tibial position in flexion (Femur 10), and three of 20 tibial shape features associated with SSD in the tibial position in flexion (Tibia 2, Tibia 4, Tibia 19). The shape features described by these modes include the sphericity of the medial femoral condyle (Femur 10; ρ = −0.38, p = 0.020); the superoinferior height of the medial femoral condyle (Femur 18; ρ = 0.34, p = 0.035); the height of the medial tibial plateau (Tibia 2; ρ = −0.32, p = 0.048); the AP length of the lateral tibial plateau (Tibia 4; ρ = −0.37, p = 0.021); and tibial slope (Tibia 19; ρ = 0.34, p = 0.038).
Conclusions
We have observed multiple bone shape features in the tibia and the femur that may be associated with abnormal knee kinematics after ACL injury and ACL reconstruction. Future directions of research will include the influence of bony morphology on clinical symptoms of instability in patients with and without ACL reconstruction and the long-term evaluation of these shape factors to better determine specific contributions to posttraumatic arthritis and graft failure.
Level of Evidence
Level II, therapeutic study.
Purpose
To describe individuals’ expectations, motivation, and satisfaction before, during, and after rehabilitation for ACL reconstruction and to explore how these factors were associated with ...return to pre-injury sport activity at 1-year follow-up.
Methods
Sixty-five individuals (34 males), median age 22 (15–45) years, scheduled for ACL reconstruction participated. Participants completed the International Knee Documentation Committee Subjective Knee Form (IKDC-SKF) and questions about expectations, satisfaction, and motivation pre-operatively and at 16 and 52 weeks after surgery.
Results
Prior to surgery, 86 % of participants stated that their goal was to return to their pre-injury sport activity. Those who had returned to their pre-injury sport activity at 52 weeks were more motivated during rehabilitation to return to their pre-injury activity level, more satisfied with their activity level and knee function at 52 weeks, and scored significantly higher on the IKDC-SKF median 92.0 (range 66.7–100.0) at 52 weeks, compared to those who had not returned median 77.6 (range 50.6–97.7).
Conclusion
Prior to ACL reconstruction, most participants expected to return to their pre-injury activity level. Higher motivation during rehabilitation was associated with returning to the pre-injury sport activity. The participants who had returned to their pre-injury sport activity were more satisfied with their activity level and knee function 1 year after the ACL reconstruction. Facilitating motivation might be important to support individuals in achieving their participation goals after ACL reconstruction.
Level of evidence
Prospective cohort study, Level II.
Injury to the anterior cruciate ligament (ACL) of the knee is potentially devastating for the patient and can result in both acute and long-term clinical problems. Consequently, the ACL has always ...been and continues to be of great interest to orthopaedic scientists and clinicians worldwide. Major advancements in ACL surgery have been made in the past few years. ACL reconstruction has shifted from an open to arthroscopic procedure, in which a two- and later one-incision technique was applied. Studies have found that traditional, transtibial arthroscopic single-bundle reconstruction does not fully restore rotational stability of the knee joint, and as such, a more anatomic approach to ACL reconstruction has emerged. The goal of
anatomic
ACL reconstruction is to replicate the knee’s normal anatomy and restore its normal kinematics, all while protecting long-term knee health. This manuscript describes the research that has changed the paradigm of ACL reconstruction from traditional techniques to present day anatomic and individualized concepts.
Background:
Anterior cruciate ligament (ACL) rupture is a well-known risk factor for development of knee osteoarthritis. Early identification of those patients at risk and early identification of the ...process of ACL rupture leading to osteoarthritis may aid in preventing the onset or progression of osteoarthritis.
Purpose:
To identify early degenerative changes as assessed on magnetic resonance imaging (MRI) after 2-year follow-up in patients with a recent ACL rupture and to evaluate which determinants are related to these changes.
Study Design:
Cohort study; Level of evidence, 2.
Methods:
Included in this study were 154 adults aged between 18 and 45 years with acute ACL rupture diagnosed by physical examination and MRI, without previous knee trauma or surgery, and without osteoarthritic changes on radiographs. A total of 143 patients completed the 2-year follow-up, and the results in this study apply to these 143 patients. All patients were treated according to the Dutch guideline on ACL injury. Of the 143 patients, 50 patients were treated nonoperatively during the 2-year follow-up period. Main outcome was early degenerative changes assessed on MRI defined as progression of cartilage defects and osteophytes in tibiofemoral and patellofemoral compartments. Patient characteristics, activity level, functional instability, treatment type, and trauma-related variables were evaluated as determinants.
Results:
The median time between MRI at baseline and MRI at 2-year follow-up was 25.9 months (interquartile range, 24.7-26.9 months). Progression of cartilage defects in the medial and lateral tibiofemoral compartments was present in 12% and 27% of patients, and progression of osteophytes in tibiofemoral and patellofemoral compartments was present in 10% and 8% of patients, respectively. The following determinants were positively significantly associated with early degenerative changes: male sex (odds ratio OR, 4.43; 95% CI, 1.43-13.66; P = .010), cartilage defect in the medial tibiofemoral compartment at baseline (OR, 3.66; 95% CI, 1.04-12.95; P = .044), presence of bone marrow lesions in the medial tibiofemoral compartment 1 year after trauma (OR, 5.19; 95% CI, 1.56-17.25; P = .007), joint effusion 1 year after trauma (OR, 4.19; 95% CI, 1.05-16.72; P = .042), and presence of meniscal tears (OR, 6.37; 95% CI, 1.94-20.88; P = .002). When the patients were categorized into 3 treatment groups (nonoperative, reconstruction <6 months after ACL rupture, and reconstruction ≥6 months after ACL rupture), there was no significant relationship between the treatment options and the development of early degenerative changes.
Conclusion:
Two years after ACL rupture, early degenerative changes were assessed on MRI. Concomitant medial cartilage defect and meniscal injury, male sex, persistent bone marrow lesions in the medial tibiofemoral compartment, and joint effusion are risk factors for degenerative changes.
Background:
Meaningful change scores in the Knee injury and Osteoarthritis Outcome Score (KOOS) in patients undergoing anterior cruciate ligament (ACL) reconstruction have not yet been established.
...Purpose:
To define the minimal important change (MIC) for the KOOS after ACL reconstruction.
Study Design:
Cohort study (diagnosis); Level of evidence, 2.
Methods:
KOOS and anchor questions with 7-point scales ranging from “better, an important improvement” to “worse, an important worsening” were completed postoperatively by randomly chosen participants from the Norwegian Knee Ligament Registry. Presurgery KOOS scores were retrieved from the registry. The MIC for improvement was calculated with anchor-based approaches using the predictive modeling method adjusted for the proportion of improved patients, the mean change method, and the receiver operating characteristic (ROC) method.
Results:
Complete data for at least one of the KOOS subscales were obtained from 542 (45.3%) participants. Predictive modeling MIC values were 12.1 for the KOOS subscales of Sport and Recreational Function and 18.3 for Knee-Related Quality of Life. These values aid in interpreting within-group improvement over time and can be used as responder criteria when comparing groups. The corresponding and much lower values for the subscales of Pain (2.5), Symptoms (–1.2), and Activities of Daily Living (2.4) are the results from patients reporting, on average, only mild problems with these domains preoperatively. Although 4% to 10% of patients reported subscale-specific worsening, MIC deterioration calculations were not possible. The ROC MIC values were associated with high degrees of misclassification. Values obtained by the mean change method were considered less reliable because these estimates are derived from subgroups of patients. Average KOOS change scores were approximately similar for patients reporting acceptable symptoms postoperatively and patients reporting important improvements on the anchor items after surgery.
Conclusion:
KOOS users should apply subscale-specific cutoffs for meaningful improvement. Our results confirm using the subscales of Sport and Recreational Function and Knee-Related Quality of Life as primary patient-reported outcomes after ACL reconstruction. The predictive modeling approach gave the most robust estimates of MIC values. Our data suggest that reporting acceptable symptoms postoperatively corresponds to reporting an important improvement after ACL reconstruction.
Disease-modifying osteoarthritis drugs (DMOADs) should reach their intra-tissue target sites at optimal doses for clinical efficacy. The dense, negatively charged matrix of cartilage poses a major ...hindrance to the transport of potential therapeutics. In this work, electrostatic interactions were utilised to overcome this challenge and enable higher uptake, full-thickness penetration and enhanced retention of dexamethasone (Dex) inside rabbit cartilage. This was accomplished by using the positively charged glycoprotein avidin as nanocarrier, conjugated to Dex by releasable linkers. Therapeutic effects of a single intra-articular injection of low dose avidin-Dex (0.5 mg Dex) were evaluated in rabbits 3 weeks after anterior cruciate ligament transection (ACLT). Immunostaining confirmed that avidin penetrated the full cartilage thickness and was retained for at least 3 weeks. Avidin-Dex suppressed injury-induced joint swelling and catabolic gene expression to a greater extent than free Dex. It also significantly improved the histological score of cell infiltration and morphogenesis within the periarticular synovium. Micro-computed tomography confirmed the reduced incidence and volume of osteophytes following avidin-Dex treatment. However, neither treatment restored the loss of cartilage stiffness following ACLT, suggesting the need for a combinational therapy with a pro-anabolic factor for enhancing matrix biosynthesis. The avidin dose used caused significant glycosaminoglycan (GAG) loss, suggesting the use of higher Dex : avidin ratios in future formulations, such that the delivered avidin dose could be much less than that shown to affect GAGs. This charge-based delivery system converted cartilage into a drug depot that could also be employed for delivery to nearby synovium, menisci and ligaments, enabling clinical translation of a variety of DMOADs.
Quantitative magnetic resonance imaging enables quantitative assessment of the healing anterior cruciate ligament or graft post‐surgery, but its use is constrained by the need for time consuming ...manual image segmentation. The goal of this study was to validate a deep learning model for automatic segmentation of repaired and reconstructed anterior cruciate ligaments. We hypothesized that (1) a deep learning model would segment repaired ligaments and grafts with comparable anatomical similarity to intact ligaments, and (2) automatically derived quantitative features (i.e., signal intensity and volume) would not be significantly different from those obtained by manual segmentation. Constructive Interference in Steady State sequences were acquired of ACL repairs (n = 238) and grafts (n = 120). A previously validated model for intact ACLs was retrained on both surgical groups using transfer learning. Anatomical performance was measured with Dice coefficient, sensitivity, and precision. Quantitative features were compared to ground truth manual segmentation. Automatic segmentation of both surgical groups resulted in decreased anatomical performance compared to intact ACL automatic segmentation (repairs/grafts: Dice coefficient = .80/.78, precision = .79/.78, sensitivity = .82/.80), but neither decrease was statistically significant (Kruskal‐Wallis: Dice coefficient p = .02, precision p = .09, sensitivity p = .17; Dunn post‐hoc test for Dice coefficient: repairs/grafts p = .054/.051). There were no significant differences in quantitative features between the ground truth and automatic segmentation of repairs/grafts (0.82/2.7% signal intensity difference, p = .57/.26; 1.7/2.7% volume difference, p = .68/.72). The anatomical similarity performance and statistical similarities of quantitative features supports the use of this automated segmentation model in quantitative magnetic resonance imaging pipelines, which will accelerate research and provide a step towards clinical applicability.
Background:
Although anterior cruciate ligament (ACL) reconstruction is the treatment gold standard for ACL injury, it does not reduce the risk of posttraumatic osteoarthritis. Therefore, new ...treatments that minimize this postoperative complication are of interest. Bioenhanced ACL repair, in which a bioactive scaffold is used to stimulate healing of an ACL transection, has shown considerable promise in short-term studies. The long-term results of this technique and the effects of the bioenhancement on the articular cartilage have not been previously evaluated in a large animal model.
Hypotheses:
(1) The structural (tensile) properties of the porcine ACL at 6 and 12 months after injury are similar when treated with bioenhanced ACL repair, bioenhanced ACL reconstruction, or conventional ACL reconstruction, and all treatments yield results superior to untreated ACL transection. (2) After 1 year, macroscopic cartilage damage following bioenhanced ACL repair is similar to that in bioenhanced ACL reconstruction and less than in conventional ACL reconstruction and untreated ACL transection.
Study Design:
Controlled laboratory study.
Methods:
A total of 64 Yucatan mini-pigs underwent ACL transection and randomization to 4 experimental groups: no treatment, conventional ACL reconstruction, bioenhanced ACL reconstruction using a bioactive scaffold, and bioenhanced ACL repair using a bioactive scaffold. The biomechanical properties of the ligament or graft were examined and macroscopic assessments of the cartilage surfaces were performed after 6 and 12 months of healing.
Results:
The structural properties (ie, linear stiffness, yield, and maximum loads) of the ligament after bioenhanced ACL repair were not significantly different from those in bioenhanced ACL reconstruction or conventional ACL reconstruction but were significantly greater than those in untreated ACL transection after 12 months of healing. Macroscopic cartilage damage after bioenhanced ACL repair was significantly less than that in untreated ACL transection and bioenhanced ACL reconstruction, and there was a strong trend (P = .068) for less macroscopic cartilage damage than in conventional ACL reconstruction in the porcine model at 12 months.
Conclusion:
Bioenhanced ACL repair produces a ligament that is biomechanically similar to an ACL graft and provides chondroprotection to the joint after ACL surgery.
Clinical Relevance:
Bioenhanced ACL repair may provide a new, less invasive treatment option that reduces cartilage damage following joint injury.
BACKGROUND:All-epiphyseal anterior cruciate ligament (ACL) reconstruction is a well-described technique for skeletally immature patients. The purpose of this study was to elucidate the early ...complication rate and identify associated risk factors for rerupture after this procedure in children.
METHODS:We retrospectively reviewed patients who underwent all-epiphyseal ACL reconstructions performed at a large, tertiary care children’s hospital between January 2007 and April 2013. Relevant postoperative data including the development of leg-length discrepancy, angular deformity, rerupture, infection, knee range of motion, arthrofibrosis, and other complications were recorded. Independent variables analyzed for association with rerupture included age, body mass index, graft type, graft size, and associated injuries addressed at surgery.
RESULTS:A total of 103 patients (average 12.1 y old; range, 6.3 to 15.7) were analyzed. The mean follow-up was 21 months. The overall complication rate was 16.5% (17/103), including 11 reruptures (10.7%), 1 case (<1.0%) of clinical leg-length discrepancy of <1 cm, and 2 cases (1.9%) of arthrofibrosis requiring manipulation under anesthesia. Two patients (1.9%) sustained contralateral ACL ruptures and 3 (2.9%) sustained subsequent ipsilateral meniscus tears during the study period. There were no associations found between age, sex, graft type, graft thickness, body mass index, or associated injuries addressed during surgery and rerupture rate. Knee flexion continued to improve by 20 degrees on an average between the 6 weeks and 6 months postoperative visits (P<0.001; paired samples Studentʼs t test).
CONCLUSIONS:When taken in the context of known risk of future injury in an ACL-deficient knee, all-epiphyseal ACL reconstruction in children is safe. The rate of growth disturbance in this study is similar to previous reports in this patient demographic. The rerupture rate in this cohort is slightly higher compared with ACL reconstruction in older patients.
LEVEL OF EVIDENCE:Level IV—retrospective case series.
PDF
