Anterior cruciate ligament reconstruction related complications: 2D and 3D high-resolution magnetic resonance imaging evaluation

Comparison of a New Radiographic Technique with MRI Measurements for Tibial Tunnel Evaluation in ACL Reconstruction

Background/Objectives: The correct angular placement of the tibial tunnel is crucial to ensure graft tension, maintain knee stability, and ensure optimal clinical outcomes after anterior cruciate ligament (ACL) reconstruction. While 3D imaging methods such as MRI and CT are the gold standard for evaluating tunnel positioning, their routine use is limited by cost, availability, and time constraints. In clinical practice, 2D radiographs are more accessible but lack established reliability in accurately estimating tunnel angles. The aim of this study was to convert 2D radiographic angular measurements used in the evaluation of patients undergoing anterior cruciate ligament reconstruction into 3D values with a simple method and to compare these measurements with three-dimensional angles calculated using conventional MRI and CT. Methods: This retrospective study included 38 patients who underwent anatomic anterior cruciate ligament reconstruction. Postoperative radiographs and MR images were analyzed to determine the tibial tunnel angles. The angles calculated from 2D radiographs were statistically analyzed for their correlation with the actual 3D angles measured by MRI. Results: The analysis showed a strong correlation between tibial tunnel angles from radiographs and MRI, with minimal, non-significant differences. This suggests that radiographs can provide a reliable estimate of tibial tunnel angles. Conclusions: These findings suggest that radiographs can predict tibial tunnel angles in ACL reconstruction as accurately as MRI. This method can guide the correct tunnel angle and facilitate postoperative evaluation. Further studies are needed to confirm these results across various populations and techniques.

Can MRI predict return to sport after anterior cruciate ligament reconstruction? A systematic review of the literature

PURPOSE

To analyze whether magnetic resonance imaging (MRI) can predict return to sport after anterior cruciate ligament (ACL) reconstruction and whether a correlation exists between return to sports, level of activity and MRI signals.

METHODS

The search terms selected for inclusion in the title, abstract, and keyword fields were as follows: 'anterior cruciate ligament' OR 'ACL' AND 'graft maturation' OR 'MRI' AND 'return to sport' OR 'sports activity.' For each study, patient data and the MRI protocol used to assess graft maturation were extracted. An analysis of the correlations between MRI and ACL reconstruction was performed.

RESULTS

A total of 394 patients were included from 7 studies. The mean radiological follow-up was 19.06 ± 11.02 months. Three studies reported no correlations between graft bending angle, signal/noise ratio, signal intensity or Howell score and return to sport. One study revealed that T2* was correlated with return to sport. A further investigation demonstrated that those who were able to regain their preinjury athletic performance exhibited considerably lower ACL/PCL ratio and ACL/muscle ratio of the ACL mid-substance compared to those who were unable to attain the same level of athletic performance. Only one study reported correlations between 12-month SNRs and 60-month Cincinnati, Lysholm and Tegner activity scales, whereas Biercevicz revealed that the combination of volume and the SI predicted the KOOS score at the 5-year follow-up.

CONCLUSIONS

There are no reliable radiological parameters available that correlate with return to sport after anterior cruciate ligament reconstruction, but MRI can potentially play a key role in closing this gap.

LEVEL OF EVIDENCE

Systematic review of level IV.

STUDY REGISTRATION

PROSPERO-CRD42024574365.

Comparative efficacy of different lengths of anterior cruciate ligament stump during reconstruction with peroneus longus tendon

BACKGROUND

Anterior cruciate ligament (ACL) injury affects individuals, and successful ACL helps patients return to an active lifestyle. This study compared the clinical effects of two treatment schemes of retention length ≥ 1/2 and < 1/2 of ACL stump in patients under reconstruction with peroneus longus tendon (PLT).

METHODS

A total of 34 patients with ACL injury of knee joint treated by unilateral ACL reconstruction with PLT were recruited in this study. They were divided into N1 (retention length of ACL stump ≥ 1/2) and N2 (retention length of ACL stump < 1/2) groups (n = 17 in each group). The knee joint proprioceptive threshold of passive motor perception was used to evaluate recovery of proprioception. The international knee documentation committee (IKDC) score, Lysholm score, and Tegner activity score (TAS) were used to evaluate knee joint functions. Lachman test, anterior drawer test (ADT), and pivot shift test (PST) were used to evaluate the stability of knee joint. Single-legged hop test and return-to-sport ratio were used to evaluate the movement ability.

RESULTS

In 6th month and 12th month after operation, the passive motor perception threshold in N1 group was better than than that in N2 group (p < 0.05). In 12th month after the operation, the return-to-sport ratio in N1 group was increased compared to the N2 group (p < 0.05). There were no significant differences in results of IKDC score, Lysholm score, TAS, Lachman test, ADT, or PST between the two groups in 6th month and 12th month after the operation (p > 0.05). In addition, no significant difference was found in the single-legged hop test between the two groups in the 12th month after operation (p > 0.05).

CONCLUSION

During ACL reconstruction with PLT, treatment strategy of ACL stump retention length ≥ 1/2 is more effective than treatment strategy of length < 1/2 for patients with ACL injury of the knee joint.

Assessment of the advantages and limitations of an innovative silk fibroin scaffold for the reconstruction of the anterior cruciate ligament with preclinical in vitro and in vivo evaluations

The gold standard treatment in anterior cruciate ligament (ACL) reconstruction involves autologous tissue transplantation, but this can have complications. Artificial grafts are an alternative, but the best option is debated. This study aimed to assess the biocompatibility and integration of a silk fibroin textile prosthesis (SF-TP) with peri-implant bone tissue and the native ACL. Twenty-six sheep underwent ACL reconstruction with SF-TP or autologous femoral fascia lata (FFL). Sheep were divided into two groups (3 and 6 months) and retrieved joints processed for histological, morphometrical and mechanical analysis. In vitro, SF-TP showed no cytotoxicity and good cell interaction up to 14 days. Histology revealed fibro-vascular tissue around SF-TP, with a progressive attempt of ligamentous-like tissue formation at 6 months. However, SF-TP group had higher joint damage scores. Micro-CT showed tunnel enlargement in SF-TP group, while FFL group had a decrease. SF-TP reconstructions had lower stiffness and strength (44 % and 64 % decrease) than those of autologous FFL reconstruction and often failed by pull-out from the bone tunnel due to tunnel enlargement. These results indicate poor osteointegration and graft motion with SF-TP, leading to joint damage/bone resorption and reduced mechanical competence. These results do not support the use of SF-TP for ACL reconstruction.

3D isotropic MRI of ankle: review of literature with comparison to 2D MRI

The ankle joint has complex anatomy with different tissue structures and is commonly involved in traumatic injuries. Magnetic resonance imaging (MRI) is the primary imaging modality used to assess the soft tissue structures around the ankle joint including the ligaments, tendons, and articular cartilage. Two-dimensional (2D) fast spin echo/turbo spin echo (FSE/TSE) sequences are routinely used for ankle joint imaging. While the 2D sequences provide a good signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) with high spatial resolution, there are some limitations to their use owing to the thick slices, interslice gaps leading to partial volume effects, limited fluid contrast, and the need to acquire separate images in different orthogonal planes. The 3D MR imaging can overcome these limitations and recent advances have led to technical improvements that enable its widespread clinical use in acceptable time periods. The volume imaging renders the advantage of reconstructing into thin continuous slices with isotropic voxels enabling multiplanar reconstructions that helps in visualizing complex anatomy of the structure of interest throughout their course with improved sharpness, definition of anatomic variants, and fluid conspicuity of lesions and injuries. Recent advances have also reduced the acquisition time of the 3D datasets making it more efficient than 2D sequences. This article reviews the recent technical developments in the domain 3D MRI, compares imaging with 3D versus 2D sequences, and demonstrates the use-case scenarios with interesting cases, and benefits of 3D MRI in evaluating various ankle joint components and their lesions.

Cruciate and Collateral Ligaments: 2-Dimensional and 3-Dimensional MR Imaging-Aid to Knee Preservation Surgery

Being a major load-bearing and dynamic functional joint of the body, the knee joint is prone to injuries to the menisci and ligaments. Injury to one or more of these structures leads to accelerated or premature osteoarthritis and chronic debilitation. The estimated cost of these injuries in terms of diagnosis, treatment, rehabilitation, and person-hours lost amounts to over a billion dollars annually. Understanding the relevant anatomy of knee cruciate and collateral ligaments, their biomechanical functional role, and imaging considerations are essential to assist multi-disciplinary communications and timely patient treatments for improved management. MRI is considered the gold standard over other imaging modalities like X-ray, ultrasound (US), and Computed Tomography (CT) for diagnosing and assessing such injuries. High-resolution 2D and 3D MRI are considerably helpful in planning for knee preservation surgery, and this article reviews the role of such imaging as a valuable aid to knee preservation surgery in pre-and post-operative states. Relevant arthroscopy correlations have been illustrated.

MR Imaging of Acute Knee Injuries: Systematic Evaluation and Reporting

Acute knee injury ranges among the most common joint injuries in professional and recreational athletes. Radiographs can detect joint effusion, fractures, deformities, and malalignment; however, MR imaging is most accurate for radiographically occult fractures, chondral injury, and soft tissue injuries. Using a structured checklist approach for systematic MR imaging evaluation and reporting, this article reviews the MR imaging appearances of the spectrum of traumatic knee injuries, including osteochondral injuries, cruciate ligament tears, meniscus tears and ramp lesions, anterolateral complex and collateral ligament injuries, patellofemoral translation, extensor mechanism tears, and nerve and vascular injuries.