Preoperative magnetic resonance imaging predicts eligibility for arthroscopic primary anterior cruciate ligament repair

Lateral extrarticular tenodesis enhances outcomes in primary anterior cruciate ligament repair with knotless anchor: 24-Month minimum follow up

BACKGROUND

Previous studies have shown that primary repair of proximal ligament avulsion from the femoral condyle may have reasonable recovery and stability rates after repair. As a result, selecting patients more narrowly and more specifically has been recognized to improve short- and medium-term outcomes.

PURPOSE

This study aimed to assess the potential benefits of primary repair for acute anterior cruciate ligament (ACL) tears with a proximal tear and to evaluate the effect of performing lateral extraarticular tenodesis (LET) in addition to primary repair on patient outcomes.

STUDY DESIGN

Retrospective cohort study.

METHODS

This study was a retrospective cohort study. Thirty-eight patients between the ages of 21 and 40 years who underwent ACL repair surgery within the first 3 weeks after injury due to Sherman type 1 proximal ACL tears were evaluated. Group 1 (n = 18) underwent only primary ACL repair with knotless anchor, while Group 2 (n = 20) had LET with iliotibial band autograft in addition to primary repair. Patients were evaluated using various tests and scoring systems at 6, 12, and 24 months postoperatively.

RESULTS

There was no statistically significant difference between the groups in preoperative and postoperative 6- and 12-month visual analog scale (VAS) scores (P >0.05). However, the 24-month VAS score of Group 1 was statistically significantly higher than that of Group 2 (P <0.05). The preoperative International Knee Documentation Committee (IKDC) score of Group 1 was statistically significantly higher than that of Group 2 (p: 0.004; P <0.05). Group 1 had statistically significantly lower IKDC scores at postoperative 6, 12, and 24 months than Group 2. Similarly, Group 1 had statistically significantly lower Single Assessment Numeric Evaluation (SANE) and Tegner-Lysholm scores at postoperative 6, 12, and 24 months than Group 2 (P <0.05). The occurrence rate of Lachman positivity in the preoperative period was 28.6% in Group 1 and 33.3% in Group 2.

CONCLUSION

Our study suggests that performing LET with iliotibial band autograft in addition to primary ACL repair may lead to better outcomes in terms of pain relief, knee function, and stability compared with primary ACL repair alone.

Return to Soccer After Acute Anterior Cruciate Ligament Primary Repair: A 2-Year Minimum Follow-up Study of 50 Amateur Players

BACKGROUND

Return to sport (RTS) after treatment of an anterior cruciate ligament (ACL) tear is a critical parameter to assess the outcome of a surgical procedure. However, few studies have investigated RTS after ACL repair.

PURPOSE

To evaluate RTS of a group of amateur soccer players at a minimum follow-up of 2 years after ACL repair.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A retrospective review of all patients treated with acute ACL repair was conducted. A total of 50 amateur soccer players were included in the study. Patients were examined clinically or contacted to complete postoperative patient-reported outcome measures, namely the Knee injury and Osteoarthritis Outcome Score, the International Knee Documentation Committee questionnaire, the ACL-Return to Sport After Injury scale, and the Forgotten Joint Score-12.

RESULTS

The patients' mean age was 25.8 ± 7.7 years (range, 14-47 years), and the mean follow-up was 34.3 ± 10.7 months (range, 24-51.3 months). The median Tegner Activity Scale score was 9. The ACL repair failure rate was 16% (8/50). The mean time from repair to failure was 23.1 ± 12.7 months (range, 6-44 months), and the mean age of patients who sustained ACL repair failure was 19.9 ± 3.3 years (range, 14-24 years), significantly lower compared with patients who did not experience ACL repair failure (26.9 ± 7.9 years; range, 16-47 years; P = .017). Multivariate analysis showed that age ≤21 years was the only significant risk factor for ACL repair failure (odds ratio, 5.45; confidence interval, 1.24-27.91; P = .041). Excluding the 8 patients who experienced repair failure, 31 of 42 patients (73.8%) returned to soccer after ACL repair, with 29 of the 31 (93.5%) returning at their preinjury level of play. Moreover, patients who played competitive soccer and returned to their preinjury level of play were significantly younger than those who did not return to their preinjury level of play (mean, 21.1 ± 3.4 vs 29.2 ± 9.5 years, respectively; P = .002) and had significantly better ACL-Return to Sport After Injury scores (mean, 96.6 ± 4 vs 87.8 ± 11, respectively; P = .044).

CONCLUSION

In this study, 73.8% (n = 31) of patients returned to playing soccer, of whom 93.5% (n = 29) returned to their preinjury level after ACL repair. The failure rate was 16% (n = 8) and mainly involved patients ≤21 years old.

Bone bruise distribution predicts anterior cruciate ligament tear location in non-contact injuries

Purpose

It is unclear whether different injury mechanisms lead to divergent anterior cruciate ligament (ACL) tear locations. This study aims to analyse the relationship between bone bruise (BB) distribution or depth and ACL tear location.

Methods

A retrospective analysis of 446 consecutive patients with acute non-contact ACL injury was performed. Only patients with complete ACL tears verified during subsequent arthroscopy were included. Magnetic resonance imaging (MRI) was used to classify BB location, BB depth, ACL tear location and concomitant injuries (medial/lateral meniscus and medial/lateral collateral ligament). Demographic characteristics included age, gender, body mass index (BMI), type of sport and time between injury and MRI. Multiple linear regression analysis was used to identify independent predictors of ACL tear location.

Results

One hundred and fifty-eight skeletally mature patients met the inclusion criteria. The presence of BB in the lateral tibial plateau was associated with a more distal ACL tear location (β = -0.27, p < 0.001). Less BB depth in the lateral femoral condyle showed a tendency towards more proximal ACL tears (β = -0.14; p = 0.054). Older age predicted a more proximal ACL tear location (β = 0.31, p < 0.001). No significant relationship was found between ACL tear location and gender, BMI, type of sport, concomitant injuries and time between injury and MRI.

Conclusion

ACL tear location after an acute non-contact injury is associated with distinct patterns of BB distribution, particularly involving the lateral compartment, indicating that different injury mechanisms may lead to different ACL tear locations.

Level of Evidence

Level III.

Arthroscopic repair of proximal anterior cruciate ligament tears in children and adolescents: A systematic review

Purpose

Anterior cruciate ligament repair techniques are of growing interest because they allow for minimally invasive surgery that avoids harvesting of the transplant, without risking growth deficiencies in young patients. The aim of this study is to summarize the published evidence about arthroscopic repair of anterior cruciate ligament proximal tears in skeletally immature patients.

Methods

In total, four studies were included and processed for data extraction after screening for eligibility for this systematic review: one retrospective cohort study and three retrospective case series. Altogether, the four studies included in this review included 61 skeletally immature patients with a mean age of 12.1 years diagnosed with proximal anterior cruciate ligament tear who underwent arthroscopic repair with preservation of the native ligament. The mean follow-up period was 2.8 years.

Results

The most relevant and objective outcome that we considered was re-rupture rate. One study reports a cumulative incidence of graft failure in the first 3 years after surgery of 48.8% while the others report a 0%, 0% and 21.5% re-rupture rate. No growth disturbances were reported in the included studies.

Conclusion

Despite growing interest surrounding anterior cruciate ligament repair techniques, the presence of limited quality studies in the literature means repair cannot be strongly supported at present. Some encouraging data regarding the absence of growth disturbance and functional outcomes does exist, but studies with larger samples are required.

Level of evidence

level IV.

Lightweight Attentive Graph Neural Network with Conditional Random Field for Diagnosis of Anterior Cruciate Ligament Tear

Anterior cruciate ligament (ACL) tears are prevalent orthopedic sports injuries and are difficult to precisely classify. Previous works have demonstrated the ability of deep learning (DL) to provide support for clinicians in ACL tear classification scenarios, but it requires a large quantity of labeled samples and incurs a high computational expense. This study aims to overcome the challenges brought by small and imbalanced data and achieve fast and accurate ACL tear classification based on magnetic resonance imaging (MRI) of the knee. We propose a lightweight attentive graph neural network (GNN) with a conditional random field (CRF), named the ACGNN, to classify ACL ruptures in knee MR images. A metric-based meta-learning strategy is introduced to conduct independent testing through multiple node classification tasks. We design a lightweight feature embedding network using a feature-based knowledge distillation method to extract features from the given images. Then, GNN layers are used to find the dependencies between samples and complete the classification process. The CRF is incorporated into each GNN layer to refine the affinities. To mitigate oversmoothing and overfitting issues, we apply self-boosting attention, node attention, and memory attention for graph initialization, node updating, and correlation across graph layers, respectively. Experiments demonstrated that our model provided excellent performance on both oblique coronal data and sagittal data with accuracies of 92.94% and 91.92%, respectively. Notably, our proposed method exhibited comparable performance to that of orthopedic surgeons during an internal clinical validation. This work shows the potential of our method to advance ACL diagnosis and facilitates the development of computer-aided diagnosis methods for use in clinical practice.

Approaching expert-level accuracy for differentiating ACL tear types on MRI with deep learning

Treatment for anterior cruciate ligament (ACL) tears depends on the condition of the ligament. We aimed to identify different tear statuses from preoperative MRI using deep learning-based radiomics with sex and age. We reviewed 862 patients with preoperative MRI scans reflecting ACL status from Hunan Provincial People's Hospital. Based on sagittal proton density-weighted images, a fully automated approach was developed that consisted of a deep learning model for segmenting ACL tissue (ACL-DNet) and a deep learning-based recognizer for ligament status classification (ACL-SNet). The efficacy of the proposed approach was evaluated by using the sensitivity, specificity and area under the receiver operating characteristic curve (AUC) and compared with that of a group of three orthopedists in the holdout test set. The ACL-DNet model yielded a Dice coefficient of 98% ± 6% on the MRI datasets. Our proposed classification model yielded a sensitivity of 97% and a specificity of 97%. In comparison, the sensitivity of alternative models ranged from 84 to 90%, while the specificity was between 86 and 92%. The AUC of the ACL-SNet model was 99%, demonstrating high overall diagnostic accuracy. The diagnostic performance of the clinical experts as reflected in the AUC was 96%, 92% and 88%, respectively. The fully automated model shows potential as a highly reliable and reproducible tool that allows orthopedists to noninvasively identify the ACL status and may aid in optimizing different techniques, such as ACL remnant preservation, for ACL reconstruction.

Two-Dimensional Magnetic Resonance Imaging in Preparation for Autograft Anterior Cruciate Ligament Reconstruction Demonstrates Quadriceps Tendon Is Thicker Than Patellar Tendon

Purpose

The purpose of this study was to assess patellar tendon (PT) and quadriceps tendon (QT) thickness on preoperative magnetic resonance imaging (MRI), in both the sagittal and axial planes, at multiple points along each tendon, and to correlate these findings to anthropometric patient data before anterior cruciate ligament (ACL) surgery.

Methods

Patients who underwent PT or QT autograft ACL reconstruction between 2020 and 2022 and who had preoperative MRIs with adequate visualization of the proximal QT and distal PT were retrospectively identified. Patient demographics were recorded (age, height, weight, sex, injury side). Preoperative MRI measurements were performed by 3 independent examiners using standardized protocol. Preoperative MRI measurements were the QT anterior-posterior (AP) thickness at 1, 2, and 4 cm from the proximal patella on axial and sagittal MRI images at the central aspect of the tendon, as well as PT AP thickness at 1, 2, and 4 cm from the distal patella on axial and sagittal MRI images at the central aspect of the tendon.

Results

Forty-one patients (21 females, 20 males) were evaluated, with a mean age of 33.4 years. The quadriceps tendon was significantly thicker than the patellar tendon at all measured locations (P < .0001) with average QT versus PT thickness (in mm) at each level sagittal 1 cm (7.13 vs 4.35), sagittal 2 cm (7.41 vs 4.44), sagittal 4 cm (7.26 vs 4.81), axial 1 cm (7.35 vs 4.50), axial 2 cm (7.63 vs 4.47), axial 4 cm (7.46 vs 4.62), respectively. There were no significant correlations between tendon size and patient body mass index.

Conclusions

The quadriceps tendon is significantly thicker than the patellar tendon at 1, 2, and 4 cm from the patella in both males and females based on preoperative MRI before ACL surgery.

Clinical relevance

Investigating the thickness of the tendons available for autograft harvest before surgery will give us a better understanding of tendon anatomy in the setting of ACL reconstruction.

Promising functional outcomes following anterior cruciate ligament repair with suture augmentation

PURPOSE

There has been a renewed interest in the repair of the torn anterior cruciate ligament (ACL). Purpose of this study was to evaluate the functional outcome of arthroscopic ACL repair with additional suture augmentation (SA), hypothesizing that isolated ACL ruptures would yield superior patient-reported outcome measures (PROMs) compared to those with concomitant meniscal and/or ligamentous injuries.

METHODS

This is a retrospective analysis of 93 consecutive patients (67 female, median age 42 years) who underwent arthroscopic ACL repair with SA between January 2017 and March 2019 for an acute traumatic ACL tear confirmed by magnetic resonance imaging (MRI). Patients with pre- or intraoperative mid-substance or distal ACL tears and/or poor tissue quality of the ACL remnant were not considered for ACL repair but were scheduled for an ACL reconstruction with a tendon autograft. In patients who underwent ACL repair with SA, the SA construct was proximally stabilized with a flip-button and distally with a suture anchor. Surgery was preferably performed on the day of injury and all surgeries were performed by the same surgeon. Postoperative rehabilitation included partial weight-bearing (20 kg) for 6 weeks and immobilization in a brace limited at 90-degrees of knee flexion for 4 weeks. Patient-reported outcome measures (PROMs) were determined using International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form, Lysholm Score (LS), Tegner Activity Score (TS) and Forgotten Joint Score (FJS). Knee-laxity was assessed using the KT-1000 arthrometer (Med Metrics Corp. Inc., San Diego, USA).

RESULTS

Nine patients underwent revision surgery for a traumatic re-tear (four patients) and chronic instability (five patients) and were excluded from further functional analysis. Functional results of 77 patients (54 female) with a median age of 44 years (IQR 33-51) on the day of surgery were available for follow-up after a median time of 35 months (IQR 33-44). Concomitant injuries were observed in 66 Patients (86%), meniscal injuries in 43 patients (55%) and ligamentous injuries in 50 patients (65%). Median interval from injury to surgery was 1 day (IQR 0-1) with 81% (62/77) of patients being treated within 24 h of injury. The median IKDC was 92 (IQR 86-99), the median LS was 95 (IQR 86-100), the median pre-traumatic TS was 7 (IQR 6-7), the median post-traumatic TS was 6 (IQR 5-7) with a non-significant median difference (TS_Diff) of 0 (IQR 0-1). The median FJS was 95 (IQR 78-98). KT-1000 measurements were available in 34 of 77 patients with a median postoperative laxity compared to the uninjured side of 1 mm (IQR 0-2). Interval from injury to surgery, patients' age, body mass index (BMI), knee laxity and concomitant ligamentous or meniscal injuries had no statistically significant impact on postoperative PROMs (n.s.).

CONCLUSION

Following arthroscopic ACL repair with SA good-to-excellent functional results were observed. However, a failure rate of 10% cannot be neglected and warrants further attention. Concomitant injuries to the meniscus and/or collateral ligaments do not seem to be associated with inferior PROMs.

LEVEL OF EVIDENCE

Level IV.

A deep learning approach for anterior cruciate ligament rupture localization on knee MR images

Purpose: To develop and evaluate a deep learning-based method to localize and classify anterior cruciate ligament (ACL) ruptures on knee MR images by using arthroscopy as the reference standard.

Methods: We proposed a fully automated ACL rupture localization system to localize and classify ACL ruptures. The classification of ACL ruptures was based on the projection coordinates of the ACL rupture point on the line connecting the center coordinates of the femoral and tibial footprints. The line was divided into three equal parts and the position of the projection coordinates indicated the classification of the ACL ruptures (femoral side, middle and tibial side). In total, 85 patients (mean age: 27; male: 56) who underwent ACL reconstruction surgery under arthroscopy were included. Three clinical readers evaluated the datasets separately and their diagnostic performances were compared with those of the model. The performance metrics included the accuracy, error rate, sensitivity, specificity, precision, and F1-score. A one-way ANOVA was used to evaluate the performance of the convolutional neural networks (CNNs) and clinical readers. Intraclass correlation coefficients (ICC) were used to assess interobserver agreement between the clinical readers.

Results: The accuracy of ACL localization was 3.77 ± 2.74 and 4.68 ± 3.92 (mm) for three-dimensional (3D) and two-dimensional (2D) CNNs, respectively. There was no significant difference in the ACL rupture location performance between the 3D and 2D CNNs or among the clinical readers (Accuracy, p < 0.01). The 3D CNNs performed best among the five evaluators in classifying the femoral side (sensitivity of 0.86 and specificity of 0.79), middle side (sensitivity of 0.71 and specificity of 0.84) and tibial side ACL rupture (sensitivity of 0.71 and specificity of 0.99), and the overall accuracy for sides classifying of ACL rupture achieved 0.79.

Conclusion: The proposed deep learning-based model achieved high diagnostic performances in locating and classifying ACL fractures on knee MR images.

In-office needle arthroscopic assessment after primary ACL repair: short-term results in 15 patients

Purpose

In-office needle arthroscopy has been reported as a diagnostic tool for different knee pathologies. In addition, ACL repair has seen a resurgence with the advent of innovative orthopedic devices. The aim of this study was to assess clinical, radiological, and in-office needle arthroscopic findings in 15 adult patients who underwent acute (within 14 days from injury) anterior cruciate ligament (ACL) repair.

Methods

Fifteen patients voluntarily participated in the study. A second-look arthroscopy was performed with an in-office needle arthroscopy at an average of 7.2 months after the primary repair. The parameters included in the investigation were the continuity of the anatomical footprint of the repaired ACL, subjective assessment of the ACL tension with the probe, and synovial coverage of the ACL. All patients had a Magnetic Resonance Imaging (MRI) at 6 months after repair and an arthrometric evaluation with the KT-1000. Clinical evaluation with the scores, Tegner Lysholm Knee Scoring Scale (TLKSS), the Knee Injury and Osteoarthritis Outcome Score (KOOS), and International Knee Documentation Committee (IKDC) was performed at the final follow-up of 2 years. Moreover, a correlation between the characteristics of ACL appearance at the time of the second look in-office needle arthroscopy, MRI and KT-1000 was performed.

Results

The mean TLKSS was 97.86, the mean KOOS was 98.08 and the mean subjective IKDC was 96.71. The objective IKDC was A in 10 patients and B in 5 patients. ACL healing was graded as A in 11 patients and B in 4 patients. Synovial coverage was graded as good in 10 patients and fair in 5 while MRI assessment showed a type I ACL in 10 patients, type II in 4 patients and type III in 1 patient.

Conclusion

In-office needle arthroscopy is a reliable tool to assess the condition of a repaired ACL. In addition, ACL repair performed in acute proximal tears demonstrated excellent clinical results.

Differential regional perfusion of the human anterior cruciate ligament: quantitative magnetic resonance imaging assessment

Purpose

Surgical reconstruction is the current standard for ACL rupture treatment in active individuals. Recently, there is renewed interest in primary repair of proximal ACL tears. Despite this, ACL biology and healing potential are currently not well understood. Vascularity is paramount in ACL healing; however, previous ACL vascularity studies have been limited to qualitative histological and dissection-based techniques. The study objective was to use contrast-enhanced quantitative-MRI to compare relative perfusion of proximal, middle, and distal thirds of the in situ ACL. We hypothesized perfusion would be greatest in the proximal third.

Methods

Fourteen cadaveric knees were studied (8 females, 6 males), age 25–61 years. Superficial femoral, anterior tibial, and posterior tibial arteries were cannulated; without intraarticular dissection. Contrast-enhanced quantitative-MRI was performed using a previously established protocol. ACL regions corresponding to proximal, middle, and distal thirds were identified on sagittal-oblique pre-contrast images. Signal enhancement (normalized to tibial plateau cartilage) was quantified to represent regional perfusion as a percentage of total ACL perfusion. Comparative statistics were computed using repeated measures ANOVA, and pairwise comparisons performed using the Bonferroni method.

Results

Relative perfusion to proximal, middle, and distal ACL zones were 56.0% ±17.4%, 28.2% ±14.6%, and 15.8% ±16.3%, respectively (p = 0.002). Relative perfusion to the proximal third was significantly greater than middle (p = 0.007) and distal (p = 0.001). No statistically relevant difference in relative perfusion was found to middle and distal thirds (p = 0.281). Post-hoc subgroup analysis demonstrated greater proximal perfusion in males (66.9% ± 17.3%) than females (47.8% ± 13.0%), p = 0.036.

Conclusion

Using quantitative-MRI, in situ adult ACL demonstrated greatest relative perfusion to the proximal third, nearly 2 times greater than the middle third and 3 times greater than the distal third. Knowledge of differential ACL vascular supply is important for understanding pathogenesis of ACL injury and the process of biological healing following various forms of surgical treatment.

Anterior cruciate ligament repair with internal brace augmentation: A systematic review

BACKGROUND

Primary repair of anterior cruciate ligament (ACL) ruptures has re-emerged as a treatment option for proximal tears, with internal brace augmentation often utilised. The aim of this study is to provide an overview of the current evidence presenting outcomes of ACL repair with internal bracing to assess the safety and efficacy of this technique.

METHODS

All studies reporting outcomes of arthroscopic primary repair of proximal ACL tears, augmented with internal bracing from 2014-2021 were included. Primary outcome was failure rate and secondary outcomes were subjective patient reported outcome measures (PROMs) and objective assessment of anteroposterior knee laxity.

RESULTS

Nine studies were included, consisting of 347 patients, mean age 32.5 years, mean minimum follow up 2 years. There were 36 failures (10.4%, CI 7.4% - 14.1%). PROMs reporting was variable across studies. KOOS, Lysholm and IKDC scores were most frequently used with mean scores > 87%. The mean Tegner and Marx scores at follow-up were 6.1 and 7.8 respectively. The mean side to side difference measured for anteroposterior knee laxity was 1.2mm.

CONCLUSIONS

This systematic review with meta-analysis shows that ACL repair with internal bracing is a safe technique for treatment of proximal ruptures, with a failure rate of 10.4%. Subjective scores and clinical laxity testing also revealed satisfactory results. This suggests that ACL repair with internal bracing should be considered as an alternative to ACL reconstruction for acute proximal tears, with the potential benefits of retained native tissue and proprioception, as well as negating the need for graft harvest.

Treatment of knee sprains in children

The incidence of knee sprains in children is steadily increasing. Skeletal immaturity and anatomical features of the child's ligamentous structures explain the frequency of bone avulsions in young children. Peripheral ligament injuries are the most common and often benign. Nevertheless, associated injuries of the cruciate or patellofemoral ligament(s) are not rare and must not be missed. Age is a determining factor in diagnostic guidance. Anterior intercondylar tibial eminence fractures, otherwise known as tibial spine fractures (TSF), usually occur in young children. Ligamentous distension at the time of the accident would explain the residual laxity that can affect the prognosis of these fractures. The treatment of interstitial ruptures of the ACL follows recommendations that are becoming clearer through multicentric studies. Reparation techniques, historically rejected as ineffective, have again become topical under specific conditions with the aim of preserving the native ACL and its proprioceptive receptors, which are essential in children. ACL reconstruction techniques have made progress in children, especially with techniques adapted from adults. Preservation of growth plates remains pertinent, especially at the femur to avoid growth disorders, thus highlighting the important role paediatric orthopaedic surgeons have in the management of these knee sprains.

Arthroscopic Primary Repair for Partial Proximal Anterior Cruciate Ligament Tear in Military Personnel

OBJECTIVE

To evaluate the short-term clinical outcomes of arthroscopic primary repair for partial proximal anterior cruciate ligament (ACL) tear in a young, active duty military population.

DESIGN

Retrospective cohort study.

SETTING

A national tertiary-level medical and academic institution.

PATIENTS

Nineteen active duty military patients with partial proximal ACL tears and excellent tissue quality were included and 18 were finally analyzed.

INTERVENTIONS

All patients underwent arthroscopic primary repair using a suture anchor technique between March 2014 and June 2016.

MAIN OUTCOME MEASURES

Clinical outcomes were evaluated using anterior drawer test (ADT), Lachman test, pivot shift test, 3-km run test, 10 m × 5 shuttle run test, physical readiness test (PRT) score, Tegner activity score, Lysholm score, modified Cincinnati score, International Knee Documentation Committee (IKDC) subjective score, and magnetic resonance imaging.

RESULTS

At final follow-up, 17 patients had negative ADT, Lachman, and pivot shift examination findings, and 1 patient had a 1+ ADT, negative Lachman, and pivot shift result. Mean 3-km run time at final follow-up was not statistically different from that preinjury (12:55 vs 12:39, P = 0.071), nor were the 10 m × 5 shuttle run time (23.4 vs 22.9, P = 0.235), PRT score (82.5 vs 85.1, P = 0.086), and Tegner activity score (7.8 vs 7.9, P = 0.083). Mean Lysholm score at final follow-up was significantly improved compared with that preoperative (93.1 vs 70.7, P < 0.001), so were the modified Cincinnati score (90.4 vs 58.6, P < 0.001) and IKDC subjective score (88.3 vs 67.4, P < 0.001).

CONCLUSIONS

Arthroscopic primary repair can achieve short-term clinical success in high-demand military patients with partial proximal ACL tears and excellent tissue quality.

Combined ACL and Segond Repair in Combined Acute Proximal ACL Tears and Segond Fracture

A renewed interest in anterior cruciate ligament preservation has been noted using arthroscopic primary repair in patients with proximal tears, but the main concern remained the control of the rotational instability. Segond fracture occurs in less than 10% of cases of acute anterolateral instability, but it can result in continued rotation instability. The aim of this study is to describe the surgical technique to acutely repair both the anterior cruciate ligament and Segond fracture in the acute setting.

Primary anterior cruciate ligament repair: magnetic resonance imaging characterisation of reparable lesions and correlation with arthroscopy

OBJECTIVES

A recent treatment algorithm suggests that proximal anterior cruciate ligament (ACL) tears with good-to-excellent tissue quality are amenable to primary repair. Our primary objective was to assess the ability of MRI to determine the exact tear location and tissue quality, using arthroscopy as a reference standard.

METHODS

In an initial sample of 71 patients with prior ACL surgery (repair or reconstruction), the diagnostic accuracy of MRI was assessed using arthroscopy as a reference standard. Each native ACL tear was graded according to Sherman's arthroscopic classifications during the surgical procedure. MRI scans were retrospectively reviewed for grading, blinded to arthroscopic findings and in consensus by two musculoskeletal radiologists. Tear location and tissue quality were graded using the MRI Sherman tear location (MSTL), MRI Sherman tissue quality (MSTQ) and simplified MRI Sherman tissue quality (S-MSTQ) classifications. Intra- and inter-observer agreement was assessed on a second sample of 77 patients. MRI classification accuracy was compared by McNemar's tests. Intra- and inter-observer agreement was assessed using Cohen's kappa coefficient.

RESULTS

Regarding tear location, diagnostic accuracy was 70% (50/71) based on the MSTL classification. Diagnostic accuracy for tissue quality was 52% (15/29) based on the MSTQ classification and 90% (26/29) for the S-MSTQ classification (p = 0.003). Inter-observer agreement was good for MSTL (κ = 0.78) and moderate-to-good for the MSTQ and S-MSTQ classifications (κ = 0.44 and 0.63 respectively).

CONCLUSIONS

MRI seems to be accurate in assessing tear location and tissue quality and may help clinicians to predict the reparability of ACL tears.

KEY POINTS

• MRI seems to be accurate in assessing tear location and tissue quality and may help clinicians to predict the reparability of ACL tears. • High intra-observer agreement was demonstrated when grading the tear location into one of five types. • The diagnostic accuracy of the simplified MRI tissue quality classification, involving deletion of the ligament stump signal criterion, was better than that observed with the MRI Sherman tissue quality classification, but was moderate to good in terms of inter- and intra-observer agreement.

Acute Primary Repair of the Anterior Cruciate Ligament With Anterolateral Ligament Augmentation

Acute injuries of the anterior cruciate ligament are often associated with concurrent injuries to the structures of the anterolateral complex, specifically the anterolateral ligament. Some injury patterns of the anterior cruciate ligament involve tearing of the majority of the ligament from the femoral origin, leaving a large, viable ligament remnant. In these patients, a repair of the anterior cruciate ligament back to the femoral origin can be undertaken. Subsequently, percutaneous repair of the anterolateral ligament can be performed through anatomical, percutaneous suture tape augmentation. The combined technique of anterior cruciate ligament repair with anterolateral ligament reinforcement is presented.

Repair versus reconstruction for proximal anterior cruciate ligament tears: a study protocol for a prospective multicenter randomized controlled trial

Background

For active patients with a tear of the anterior cruciate ligament (ACL) who would like to return to active level of sports, the current surgical gold standard is reconstruction of the ACL. Recently, there has been renewed interest in repairing the ACL in selected patients with a proximally torn ligament. Repair of the ligament has (potential) advantages over reconstruction of the ligament such as decreased surgical morbidity, faster return of range of motion, and potentially decreased awareness of the knee. Studies comparing both treatments in a prospective randomized method are currently lacking.

Methods

This study is a multicenter prospective block randomized controlled trial. A total of 74 patients with acute proximal isolated ACL tears will be assigned in a 1:1 allocation ratio to either (I) ACL repair using cortical button fixation and additional suture augmentation or (II) ACL reconstruction using an all-inside autologous hamstring graft technique. The primary objective is to assess if ACL repair is non-inferior to ACL reconstruction regarding the subjective International Knee Documentation Committee (IKDC) score at two-years postoperatively. The secondary objectives are to assess if ACL repair is non-inferior with regards to (I) other patient-reported outcomes measures (i.e. Knee Injury and Osteoarthritis Outcome Score, Lysholm score, Forgotten Joint Score, patient satisfaction and pain), (II) objective outcome measures (i.e. failure of repair or graft defined as rerupture or symptomatic instability, reoperation, contralateral injury, and stability using the objective IKDC score and Rollimeter/KT-2000), (III) return to sports assessed by Tegner activity score and the ACL-Return to Sports Index at two-year follow-up, and (IV) long-term osteoarthritis at 10-year follow-up.

Discussion

Over the last decade there has been a resurgence of interest in repair of proximally torn ACLs. Several cohort studies have shown encouraging short-term and mid-term results using these techniques, but prospective randomized studies are lacking. Therefore, this randomized controlled trial has been designed to assess whether ACL repair is at least equivalent to the current gold standard of ACL reconstruction in both subjective and objective outcome scores.

Trial registration

Registered at Netherlands Trial Register (NL9072) on 25th of November 2020.

Arthroscopic Primary Repair of the Posterior Cruciate Ligament

The posterior cruciate ligament (PCL) is one of the four major stabilizers of the knee joint and functions as the primary restraint to posterior tibial translation. PCL tears rarely occur in isolation and most commonly presents in the setting of multiligamentous knee injuries. Several treatment strategies for these injuries have been proposed over the last decades, including ligament reconstruction and primary repair. Arthroscopic primary PCL repair has the potential to preserve native tissue using a more minimally invasive approach, thereby avoiding donor-site morbidity and allowing early mobilization. While arthroscopic PCL repair is certainly not an effective surgical approach for all patients, this procedure may be a reasonable and less morbid alternative to PCL reconstruction in selected patients treated for proximal or distal avulsion tears, with low failure rates, good knee stability, and good to excellent subjective outcomes. The surgical indications, surgical techniques, postoperative management, and outcomes for arthroscopic primary repair of proximal and distal PCL tears will be discussed in this review.

Standard MRI May Not Predict Specific Acute Anterior Cruciate Ligament Rupture Characteristics

Background

There has been renewed interest in the concept of anterior cruciate ligament (ACL) suture repair (ACLSR). Morphologic characteristics of the ruptured ACL remnant play a role in deciding whether a patient is eligible for ACLSR. However, no classification of these characteristics of ACL rupture on magnetic resonance imaging (MRI) scans has yet been compared with intraoperative findings in the context of ACLSR.

Purpose

To investigate the value of using preoperative MRI to predict specific characteristics of acute complete ACL rupture.

Study Design

Cohort study (diagnostic); Level of evidence, 2.

Methods

A total of 25 patients were included. Two radiologists classified ACL rupture location and pattern on preoperative 1.5-T MRI scans with a standard sequence; the results were compared with the corresponding findings at arthroscopy conducted by a single surgeon. The agreement between the MRI and surgical findings was calculated using Cohen κ values. Furthermore, the reliability coefficients of the MRI classifications within and between radiologists were calculated.

Results

The agreement between MRI classification and arthroscopic findings for ACL rupture location was slight (Cohen κ, 0.016 [radiologist 1] and 0.087 [radiologist 2]), and for ACL rupture pattern, this was poor to slight (Cohen κ, <0 and 0.074). The intraobserver reliability of MRI classification for ACL rupture location was moderate for radiologist 1 and slight for radiologist 2 (Cohen κ, 0.526 and 0.061, respectively), and for ACL rupture pattern, this was slight for radiologist 1 and 2 (Cohen κ, 0.051 and 0.093, respectively). The interobserver reliability of MRI classification for ACL rupture location and pattern was slight between radiologists (Cohen κ, 0.172 and 0.040, respectively).

Conclusion

In the current study, we found poor to slight agreement between MRI classification and arthroscopic findings of specific ACL rupture characteristics. In addition, the intra- and interobserver reliability for MRI classification of the ACL rupture characteristics was slight to moderate.

ACL Repair: A Game Changer or Will History Repeat Itself? A Critical Appraisal

Until the past decade the common thought was that the anterior cruciate ligament (ACL) was not able to heal and restore knee stability. In this manuscript a brief review of studies of the developers and the early adaptors of four different modern ACL repair techniques are presented. The present status and considerations for the future of ACL repair and its research are shared. After promising short- to midterm ACL healing results by the developers, the results of the early adaptors show more variety in terms of rerupture and reintervention for other reasons. Risk factors for failure are a young age, high preinjury sports activity level, midsubstance ruptures and impaired integrity of the ACL bundles and the synovial sheath. There is a call for more clinical data and randomized clinical trials. Conclusion: an important finding of the past decade is that the ACL is able to heal and subsequently restabilize the knee. Patient selection is emphasized: the ideal patient is a non-high athlete older than 25 and has an acute proximal one bundle ACL rupture. Further research will have to show if ACL repair could be a game changer or if history will repeat itself.

Anterior Cruciate Ligament Repair: Historical Perspective, Indications, Techniques, and Outcomes

Anterior cruciate ligament (ACL) repair was first reported in 1895 by Sir Arthur Mayo-Robson. Open primary ACL repair was performed throughout the 1970s and 1980s; however, rerupture rates were as high as 50% at mid-term follow-up. Throughout the 1980s and 1990s, synthetic graft materials received consideration; however, the outcomes were abysmal. Recently, with a better understanding of ACL healing and improvement in technique, there has been renewed interest in ACL repair. The potential advantages of ACL repair include improvements in knee kinematics and proprioception, avoiding graft harvest, and preserving bone stock. Although recent data on short-term outcomes suggest potential in properly indicated patients, medium- and long-term outcomes are largely unknown. ACL repair has the greatest potential in cases of proximal ACL rupture (modified Sherman type I and II proximal tears). Repair of midsubstance tears (modified Sherman type III tears) should be avoided. Caution is advised in athletes and younger patients because of higher failure rates. Today, ACL repair remains controversial and should be performed with caution because of limited medium- and long-term outcomes.

Inter- and Intraobserver Reliability Between Orthopaedic Surgeons for Reparability of the Anterior Cruciate Ligament Using MRI

Background

Anterior cruciate ligament (ACL) reconstruction is the standard of care for patients after an ACL tear, as poor historical outcomes were observed after primary ACL repair. Certain subgroups of patients, however, have been shown to have outcomes equivalent to reconstruction after undergoing ACL repair and therefore may benefit from the potential advantages offered by avoiding reconstruction. It is important to accurately and consistently identify and indicate these candidates for ACL repair.

Purpose/Hypothesis

The purpose of this study was to determine the inter- and intraobserver reliability of magnetic resonance imaging (MRI) evaluation for the reparability of ACL tears and to identify imaging factors that may lead to surgeon uncertainty or disagreement in decision making. Our hypothesis was that the orthopaedic surgeons surveyed would not be able to reliably agree on the reparability of an ACL using MRI scans alone.

Study Design

Cohort study (diagnosis); Level of evidence, 3.

Methods

We administered 2 surveys to 6 fellowship-trained orthopaedic sports medicine surgeons. Each surgeon reviewed preoperative MRI scans for 20 patients and answered a series of questions, ultimately determining whether they would choose an ACL reconstruction or repair for the patient based on the imaging alone. The same survey was repeated 6 weeks later. Kappa values for inter- and intraobserver reliability of their decision making were then calculated.

Results

The average kappa for interobserver reliability in the 2 surveys was 0.22, and the average kappa for intraobserver reliability was 0.34. Interobserver reliability among the surgeons in this group was poor to moderate; intraobserver reliability was slightly better. The choice for ACL repair was significantly correlated with proximal tear locations (r = 0.854; P < .001), good-quality ACL tissue remnant (r = 0.929; P < .001), and how many surgeons believed that the tear only involved a single bundle (r = 0.590; P = .006).

Conclusion

The surgeons surveyed in this study did not consistently agree on candidates for ACL repair using MRI alone.

The healing potential of an acutely repaired ACL: a sequential MRI study

Background

Recently, there has been renewed interest in primary anterior cruciate ligament (ACL) repair. The aim of this study is to report early clinical and radiological results of a consecutive series of acute ACL tears treated with arthroscopic primary ACL repair within 14 days from injury.

Patients and methods

A consecutive series of patients with acute ACL tears were prospectively included in the study. Based on MRI appearance, ACL tears were classified into five types, and tissue quality was graded as good, fair, and poor. Patients with type I, II, and III tears and at least 50% of ACL tibial remnant intact with good tissue quality were ultimately included. Clinical outcomes were measured using the Tegner Lysholm Knee Scoring Scale (TLKSS), the Knee Injury and Osteoarthritis Outcome Score (KOOS), subjective and objective International Knee Documentation Committee (IKDC) scores, and KT-1000. Patients were also followed up with MRI evaluations at 1, 3, and 6 months postoperatively. ACL appearance was graded based on morphology (normal or abnormal) and signal intensity (isointense, intermediate, and hyperintense).

Results

The mean TLKSS was 98.1, the mean subjective IKDC was 97.6, and the mean KOOS was 98.2. The objective IKDC score was A in eight of ten patients and B in two patients. KT-1000 measurements showed a maximum manual side-to-side difference of less than 2 mm in eight of ten patients, whereas two patients showed a difference of 3 mm. The morphology of the repaired ACL was normal (grade 1) at 1 month follow-up in ten of ten cases, and this appearance persisted at 3 and 6 months postoperatively. The signal intensity at 1 month postoperatively was graded as isointense (grade 1) in four of ten patients, intermediate (grade 2) in five of ten patients, and hyperintense (grade 3) in one of ten patients. At both 3 and 6 months postoperatively, the signal intensity was graded as isointense (grade 1) in nine of ten patients and intermediate (grade 2) in one of ten patients.

Conclusions

Arthroscopic primary ACL repair performed acutely in a carefully selected group of patients with proximal ACL tears and good tissue quality showed good early clinical and radiological results.

Level of evidence

Level 4.

Is Primary Arthroscopic Repair Using the Pulley Technique an Effective Treatment for Partial Proximal ACL Tears?

BACKGROUND

Attention has recently been paid to primary arthroscopic repair to treat ACL tears because of the disadvantages associated with reconstruction. However, there remain many unanswered questions and concerns about its application in the treatment of ACL tears.

QUESTIONS/PURPOSES

(1) Does primary arthroscopic repair using the pulley technique result in satisfactory ROM (a functional ROM with a flexion contracture of 30° or less), knee stability, and functional scores in patients with partial proximal ACL tears? (2) What complications are associated with primary arthroscopic repair using the pulley technique in patients with partial proximal ACL tears?

METHODS

Between January 2014 and March 2016, we treated 23 patients surgically who had partial proximal ACL tears and excellent tissue quality (defined as a remnant with mild interstitial tearing and the ability to hold sutures). All patients meeting those two criteria were treated using primary arthroscopic repair using the pulley technique. During that period, this represented 13% (23 of 183) of the patients we treated surgically for an ACL tear. Patients were excluded if they had other ACL tear types, insufficient tissue quality (defined as a severely torn remnant that was not strong enough to hold sutures), multi-ligamentous injuries, or substantial arthrosis (chondromalacia greater than Outerbridge grade 3, most of which underwent conversion to ACL reconstruction). Clinical outcomes were assessed using ROM, the anterior drawer test, the Lachman test, Lysholm score, Tegner activity score, IKDC subjective score, and radiographs. Twenty-one patients were observed for a mean (range) period of 36 months (25-49), and two were lost to follow-up.

RESULTS

At the most-recent follow-up examination, all patients achieved full extension and only one patient lacked full flexion, with a flexion contracture of 10°. Twenty patients had no instability on the anterior drawer test and Lachman test findings, and one patient had a 1 + anterior drawer test. The mean Lysholm score improved from a mean ± SD of 71 ± 9 before surgery to 94 ± 6 (mean difference 23 points [95% CI 20 to 25]; p < 0.001) at latest follow-up. The IKDC subjective score improved from 64 ± 10 to 86 ± 11 points (mean difference 22 points; p < 0.001). We found no difference in the Tegner score from before surgery to latest follow-up (6.3 ± 1.2 versus 6.1 ± 1.2; mean difference 0.2; p = 0.056). One patient re-ruptured his ACL 2 months after surgery in military training during an obstacle race. No complications such as infection, thrombosis, stiffness, patellofemoral pain, or implant failure were observed.

CONCLUSIONS

Primary arthroscopic repair using the pulley technique can achieve short-term clinical success in a carefully selected (the selection process includes first identifying the ACL injury pattern preoperatively with MRI, then confirming the diagnosis under arthroscopy, and deciding whether to perform a repair intraoperatively) subset of patients with partial proximal ACL tears and excellent tissue quality (defined as a remnant with mild interstitial tearing and the ability to hold sutures). Despite the promising clinical outcomes of our study, this technique should not be widely adopted unless it has been compared directly with ACL reconstruction, so future studies should be conducted to compare the clinical outcomes between this technique and ACL reconstruction, and longer-term follow-up is necessary to identify whether there is deterioration in the clinical outcomes over time.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Arthroscopic primary repair of proximal anterior cruciate ligament tears seems safe but higher level of evidence is needed: a systematic review and meta-analysis of recent literature

PURPOSE

To assess the outcomes of the various techniques of primary repair of proximal anterior cruciate ligament (ACL) tears in the recent literature using a systematic review with meta-analysis.

METHODS

PRISMA guidelines were followed. All studies reporting outcomes of arthroscopic primary repair of proximal ACL tears using primary repair, repair with static (suture) augmentation and dynamic augmentation between January 2014 and July 2019 in PubMed, Embase and Cochrane were identified and included. Primary outcomes were failure rates and reoperation rates, and secondary outcomes were patient-reported outcome scores.

RESULTS

A total of 13 studies and 1,101 patients (mean age 31 years, mean follow-up 2.1 years, 60% male) were included. Nearly all studies were retrospective studies without a control group and only one randomized study was identified. Grade of recommendation for primary repair was weak. There were 9 out of 74 failures following primary repair (10%), 6 out of 69 following repair with static augmentation (7%) and 106 out of 958 following dynamic augmentation (11%). Repair with dynamic augmentation had more reoperations (99; 10%), and more hardware removal (255; 29%) compared to the other procedures. All functional outcome scores were > 85% of maximum scores.

CONCLUSIONS

This systematic review with meta-analysis found that the different techniques of primary repair are safe with failure rates of 7-11%, no complications and functional outcome scores of > 85% of maximum scores. There was a high risk of bias and follow-up was short with 2.1 years. Prospective studies comparing the outcomes to ACL reconstruction with sufficient follow-up are needed prior to widespread implementation.

LEVEL OF EVIDENCE

IV.

Primary Arthroscopic Repair of the Anterior Cruciate Ligament: A Systematic Review of Clinical Outcomes

PURPOSE

To describe the clinical outcomes after primary arthroscopic anterior cruciate ligament (ACL) repair.

METHODS

A systematic review of the PubMed, Embase, and Cochrane Library databases was performed according to the PRISMA guidelines. All English-language literature published from 2000 to 2018 that reported the clinical outcomes after primary arthroscopic repair (AR) of complete tear of the ACL (without augmentation) with a minimum 2-year follow-up was reviewed by 2 independent reviewers. Outcomes included repair failure, reoperation, postoperative knee stability, and patient-reported outcomes. Descriptive statistics are presented. Study quality was evaluated with the Modified Coleman Methodology Score (MCMS) and the Methodological Index for Nonrandomized Studies (MINORS) score.

RESULTS

Six studies (2 level III, 4 level IV) were included. The mean MCMS was 62.2. The mean MINORS score for noncomparative studies was 11.8, and for comparative studies, 18. Six studies reported outcomes of 89 patients who underwent AR of the ACL from 2007 to 2016 (age, 8 to 67 years; follow-up, 24 to 110 months). All 6 studies included exclusively proximal avulsion tears. Overall, 0% to 25.0% of patients experienced repair failure (I² = 23.7%; 95% confidence interval, 0% to 67.6%), and 0% to 20.0% of patients had a subsequent reoperation (I² = 12.1%; 95% confidence interval, 0% to 77.7%). Similar inconsistent results were shown for postoperative knee stability measures and patient-reported outcomes.

CONCLUSIONS

The literature on clinical outcomes of primary arthroscopic ACL repair is limited. The reported rates of repair failure and reoperation are highly inconsistent. Most studies report relatively high failure rates.

LEVEL OF EVIDENCE

IV, systematic review of level III and IV studies.

Arthroscopic primary repair of the anterior cruciate ligament in adults: a systematic review

BACKGROUND

The most common procedure to manage a torn anterior cruciate ligament (ACL) is surgical reconstruction. Primary repair of the ACL is returning on the forefront in the management of acute ACL, aiming to be less invasive and preserve the original ligament. Several techniques have been reported; the present systematic review investigates the clinical outcomes of ACL primary repair in adults.

SOURCES OF DATA

Following an electronic search through Medline, Cochrane and Google Scholar databases, articles of interest were retrieved and evaluated, including case series, retrospective studies, case-control studies and randomized controlled trials. The main outcome data were extracted and summarized in tables and text. The methodology of the studies was assessed using the Coleman methodology score (CMS).

AREAS OF AGREEMENT

Of the articles included, one was of level I, two of level III and the remaining of level IV. The direct intraligamentary stabilization technique was the most widely and accurately reported technique, with acceptable success and improvement of functional outcomes. The CMS averaged 58.75 (range 48 to 69), with no significant association with year of publication (Pearson's regression r = -0.397, P = 0.207).

AREAS OF CONTROVERSY

Concerning stump sutures and suture anchors repair, although leading to good results, also in comparison with ACL reconstruction, no sufficient evidence was available to support these techniques.

GROWING POINTS

The overall good results were reported also for other techniques are not supported by adequate evidence. More and better trials are required to improve our knowledge and understanding in this controversial area.

Figure-of-4 Cruciate Remnant Objective Assessment Test Reducibility of Anterior Cruciate Ligament Stump for Feasibility of Arthroscopic Primary Anterior Cruciate Ligament Repair

Suture of the anterior cruciate ligament (ACL) has reemerged as a treatment option for proximal ACL tears. Preoperative imaging can provide insight into the feasibility of performing arthroscopic primary ACL repair, but the final decision is taken only after confirming with arthroscopy that the ACL remnant is reducible. We describe a test called the Figure-of-4 Cruciate Remnant Objective Assessment test that objectively interprets the reducibility of the ACL remnant for arthroscopic primary ACL repair.

Identifying candidates for arthroscopic primary repair of the anterior cruciate ligament: A case-control study

INTRODUCTION

There has been a recent resurgence of interest in arthroscopic primary repair of proximal anterior cruciate ligament (ACL) tears. Patient selection is critical but not much is currently known on what predicts the possibility of repair. Goal of this study was therefore to assess predictive factors for the possibility of arthroscopic primary ACL repair.

METHODS

In this retrospective case-control study, all patients undergoing ACL surgery in a ten-year interval were included. Patients were treated with primary repair if there was a proximal tear and good tissue quality, or otherwise underwent ACL reconstruction. Collected data were age, gender, BMI, injury-to-surgery delay, injury mechanism and concomitant injuries. Receiver operating characteristic curves were used to find cutoff values, and all significant dependent variables were used in multivariate logistic analysis to assess independent predictors for the possibility of primary repair.

RESULTS

Three hundred sixty-one patients were included, of which in 158 patients (44%) primary repair was possible. Multivariate analysis (R² = 0.340, p < 0.001) showed that age > 35 years (Odds ratio [OR] 4.2, 95% CI 2.4-7.5,p < 0.001), surgery within 28 days (OR 3.3, 95% CI 1.9-5.7, p < 0.001), and BMI <26 (OR 1.9, 95% CI 1.1-3.3,p = 0.029) were predictive for the possibility of primary repair, and lateral meniscus injury presence decreased the likelihood of repair (OR 0.5, 95% CI 0.3-0.8, p = 0.008).

CONCLUSION

In this large cohort study, it was noted that 44% of patients had repairable ACL tears. Primary repair was more likely to be possible in older patients, patients with lower BMI and when surgery was performed within four weeks of injury.

Short-Term Outcome of Multi-Ligament Knee Injury among Sudanese Patients

BACKGROUND:

Multi-ligament knee injury is the state of having two or more of the major knee ligaments, namely: the anterior cruciate ligament (ACL), the posterior cruciate ligament (PCL), the medial collateral ligament (MCL), the lateral collateral ligament (LCL), the posteromedial corner (PMC), and the posterolateral corner (PLC). The knee is a hinge joint; this dictates two direction movements on the y-axis plane. The knee joints carry the weight load of the body uniquely. The role of the knee ligaments is not conserved only to maintain knee in a rigid position while standing, but also orchestrates the biomechanics of knee motion in harmony. Multi-ligament knee injury is very rare (incidence < 10:10,000 of trauma cases). Patients with multiple ligaments injuries of the knee become disabled for a long period. This disability rises from the pain and stiffness of the knee joint. A disability that might be associated with increased frequencies of sick leave from work, or much more dire consequences, such as quitting a job or being relieved of duty.

AIM:

To assess the functional outcome of the knee of patients with a multi-ligament knee injury after treatment using a standard scoring system and to determine the recovery rates of each treatment option to a multi-ligament knee injury.

METHODS:

it is a cross-sectional study conducted from January 2018 to January 2019. All patients with multi-ligament knee injuries that were diagnosed by MRI, and underwent reconstruction surgeries or on the waiting list, at Ribat University Hospital and Alyaa Specialized Hospital, Alkuwiti specialised hospital, and Haj Alsafi Hospital for the past 2 years were included. Lyshlome knee scoring scale was used to assess the functional outcome of each patient.

RESULTS:

24 patients were enrolled in this study (16 had reconstruction surgery, 8 did not). 3 had excellent outcome (LKSS = 95 – 100), 8 of them had good score (LKSS = 84-94), 5 had fair outcome (LKSS = 65-83). All those who did not have reconstruction had a poor score (LKSS < 64).

CONCLUSION:

Reconstruction of multi-ligament knee injury shows a good outcome than it was left alone. Post-operative physiotherapy increases the potential of reconstruction. While our data is limited because of the rare condition, we plan to expand our study area to include a larger sample size. We also recommend extending the post-operative physiotherapy to improve the outcome of a multi-ligament knee injury.

Multiligament Repair With Suture Augmentation in a Knee Dislocation With Medial-Sided Injury

Knee dislocations often result in a severe multiligament injured knee (MLIK) with complex instability. Multiligament reconstruction can successfully restore knee stability and is commonly recommended, although surgical morbidity is induced by graft harvesting and tunnel drilling, and convergence of multiple tunnels can complicate the surgery. Therefore, as an alternative, primary repair of knee ligaments is currently reconsidered. The main advantages of primary repair consist of tissue preservation and decrease of surgical morbidity, which might improve knee functionality. Techniques in which avulsed ligaments are reapproximated to their anatomic origin have resulted in good clinical outcomes in selected patients over the past decade. More recently, repaired ligaments have been augmented with suture tape, to protect them from excessive stretch, which can improve healing and allows early rehabilitation. The surgical technique of primary repair in the multiligament injured knee has not yet been described. The purpose of this Technical Note is to explain suture augmented primary repair in KDIII-M injury, including the anterior cruciate ligament, posterior cruciate ligament, and medial collateral ligament.

Validation of Noncontact Anterior Cruciate Ligament Tears Produced by a Mechanical Impact Simulator Against the Clinical Presentation of Injury

BACKGROUND

Anterior cruciate ligament (ACL) injuries are catastrophic events that affect athletic careers and lead to long-term degenerative knee changes. As injuries are believed to occur within the first 50 milliseconds after initial contact during a rapid deceleration task, impact simulators that rapidly deliver impulse loads to cadaveric specimens have been developed. However, no impactor has reproducibly and reliably created ACL injures in a distribution that mimics clinical observation.

PURPOSE

To better understand ACL injury patterns through a cadaveric investigation that applied in vivo-measured external loads to the knee during simulated landings.

STUDY DESIGN

Controlled laboratory study.

METHODS

A novel mechanical impact simulator reproduced kinetics from in vivo-recorded drop landing tasks on 45 cadaveric knees. Specimens were exposed to a randomized order of variable knee abduction moment, anterior tibial shear, and internal tibial rotation loads before the introduction of an impulse load at the foot. This process was repeated until a hard or soft tissue injury was induced on the joint. Injuries were assessed by an orthopaedic surgeon, and ligament strain was recorded by implanted strain gauges.

RESULTS

The mechanical impact simulator induced ACL injuries in 87% of specimens, with medial collateral ligament (MCL) injuries in 31%. ACL tear locations were 71% femoral side, 21% midsubstance, and 9% tibial side. Peak strain before failure for ACL-injured specimens was 15.3% ± 8.7% for the ACL and 5.1% ± 5.6% for the MCL ( P < .001).

CONCLUSION

The ACL injuries induced by the mechanical impact simulator in the present study have provided clinically relevant in vitro representations of in vivo ACL injury patterns as cited in the literature. Additionally, current ligament strains corroborate the literature to support disproportionate loading of the ACL relative to the MCL during athletic tasks.

CLINICAL RELEVANCE

These findings indicate that the mechanical impact simulator is an appropriate model for examining independent mechanical variables, treatment techniques, and preventive interventions during athletic tasks leading up to and including an ACL injury. Accordingly, this system can be utilized to further parse out contributing factors to an ACL injury as well as assess the shortcomings of ACL reconstruction techniques in a dynamic, simulated environment that is better representative of in vivo injury scenarios.

Arthroscopic primary repair of the anterior cruciate ligament: what the radiologist needs to know

Recently, there has been a renewed interest in primary repair of proximal anterior cruciate ligament (ACL) tears. Magnetic resonance imaging (MRI) plays an important role in preoperative patient selection and in postoperative ligament assessment. Knowledge of the imaging factors that make patients candidates for primary ACL repair, namely proximal tear location and good tissue quality, can help radiologists provide information that is meaningful for surgical decision making. Furthermore, an understanding of the surgical techniques can prevent misinterpretation of the postoperative MRI. This article reviews preoperative MRI characterization of ACL injuries, techniques of arthroscopic primary ACL repair surgery and examples of postoperative MRI findings.

Ligament Strain Response Between Lower Extremity Contralateral Pairs During In Vitro Landing Simulation

Background:

Limb asymmetries, as determined through in vivo biomechanical measures, are known risk factors for anterior cruciate ligament (ACL) injury. Previous cadaveric studies have shown a lack of significant differences in ligament strain between contralateral lower extremities when identical kinematics were simulated on specimens. Recent methodological developments have applied in vivo knee kinetics to exert landing forces on cadaveric lower extremities to mimic ACL injury events, but it is unknown whether contralateral limbs fail in a consistent manner during impact simulator testing.

Hypothesis:

It was hypothesized that contralateral lower extremities would not exhibit side-to-side differences in ligament strains. Furthermore, it was hypothesized that failure loads and failure locations would be independent of limb dominance.

Study Design:

Controlled laboratory study.

Methods:

Fourteen pairs of cadaveric lower extremities were obtained from an anatomic donations program (8 female, 6 male; mean ± SD: age, 41.7 ± 8.1 years; mass, 86.8 ± 27.0 kg; body mass index, 29.4 ± 9.0 kg/m²). A mechanical impact simulator was used to re-create the impulse ground-reaction force generated during an in vivo landing task. Ligament strains were recorded by differential variable force transducers implanted on the ACL and medial collateral ligament (MCL).

Results:

No significant differences were observed in peak ACL or peak MCL strain for 5 loading conditions. Fisher exact tests of independence revealed that limb dominance was independent of both load at failure and failure location.

Conclusion:

There were no significant differences in ACL and MCL strain values between limb sides during in vitro impact simulation testing. This finding indicates that limb dominance does not influence the failure threshold of the ACL, since there was no significant difference in failure strains. The functional mechanics of the ACL are comparable between contralateral pairs from the same healthy specimen.

Clinical Relevance:

Injury mechanisms and intra-articular mechanics cannot be ethically studied in an in vivo setting. The current study provides additional insight into limb asymmetry that is observed among athletes in clinical sports medicine settings.

Clinical Outcomes of Arthroscopic Primary Repair of Proximal Anterior Cruciate Ligament Tears Are Maintained at Mid-term Follow-up

PURPOSE

To assess the mid-term clinical outcomes in patients with proximal avulsion anterior cruciate ligament (ACL) tears undergoing arthroscopic primary repair with suture anchors.

METHODS

The first 11 consecutive patients with proximal avulsion tears treated with arthroscopic primary repair were evaluated at mid-term (minimum 5-year) follow-up. Physical examination was performed; laxity examination consisting of the Lachman, pivot-shift, and anterior drawer tests was performed; and patients were asked to complete the Lysholm, modified Cincinnati, Single Assessment Numeric Evaluation, and International Knee Documentation Committee (IKDC) questionnaires.

RESULTS

Of the 11 patients, 10 were seen at a mean follow-up of 6.0 ± 1.5 years (range, 4.8-9.2 years). One patient was lost to follow-up, in whom failure had already occurred at short-term follow-up. One additional patient underwent reoperation for a medial meniscus tear and also had a partial ACL tear; this patient was clinically stable at last follow-up. All patients had full range of motion. Nine patients had negative Lachman and negative pivot-shift examination findings (IKDC score of A), and 1 patient had a 1A Lachman result and 1+ pivot-shift result (IKDC score of B). The mean Lysholm score was 96.0 ± 4.5 (range, 88-100); modified Cincinnati score, 95.6 ± 7.4 (range, 80-100); Single Assessment Numeric Evaluation score, 95.4 ± 5.4 (range, 85-100); preinjury Tegner score, 7.2 ± 1.2 (range, 5-9); postoperative Tegner score, 6.6 ± 1.8 (range, 3-9); and IKDC subjective score, 92.3 ± 11.3 (range, 64-100).

CONCLUSIONS

The clinical outcomes of arthroscopic primary repair of proximal ACL tears with suture anchors are excellent and are maintained at mid-term follow-up in a carefully selected subset of patients with proximal tears and excellent tissue quality.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.