Adjustable loop femoral cortical suspension devices for anterior cruciate ligament reconstruction: a systematic review

Background: Anterior cruciate ligament (ACL) injury is a common sports injury. Symptomatic knee instability after this injury is usually treated operatively through ACL reconstruction. The surgery involves a tendon graft being fixed in bony tunnels drilled through femur and tibia. The fixation of the graft is of critical importance to achieving good results. One of the commonest devices used to fix the graft in the femoral bony tunnel is a fixed loop cortical suspensory device. More recently, adjustable loop cortical suspension devices have been introduced, and have gained popularity for ACL reconstruction. These allow for adjusting the length of the suspension loop after insertion. There is currently much debate concerning whether the adjustable loop devices are superior or inferior to the fixed loop devices. Purpose: To critique and review the current biomechanical and clinical evidence on the use of adjustable loop devices in hamstring ACL reconstruction. To our knowledge, there have been no previous reviews of this topic. Study Design: Systematic review. Methods: This systematic review was conducted in accordance with PRISMA. Five databases were searched using multiple search terms and MeSH terms where possible. The following limits were applied: papers published in English and papers published in the last 21 years. Results: Eleven laboratory and six clinical studies were reviewed. The laboratory-based studies have frequently shown elongation of adjustable loop devices to more than 3 mm under loading protocols, whereas the clinical studies have not shown any significant differences between the patients with fixed loop and the ones with adjustable loop devices. Clinical Significance: This review shows a discrepancy between laboratory-based and clinical studies. The review of clinical studies in our paper would give future researchers confidence and act as a prompt to construct randomised clinical trials to investigate these devices further. Conclusion: We feel that more robust clinical randomised studies and trials are needed to evaluate these new devices

A comparison of femoral tunnel placement in ACL reconstruction using a 70° arthroscope through the anterolateral portal versus a 30° arthroscope through the anteromedial portal: a pilot 3D-CT study

Background: Graft malposition is a risk factor for failure of anterior cruciate ligament reconstruction. A 70° arthroscope improves visualisation of the medial wall of the lateral femoral condyle without switching portals. We investigated whether the use of this arthroscope affected the accuracy and precision of femoral tunnel placement. Methods: Fifty consecutive adult patients were recruited. Following one withdrawal and two exclusions, 47 patients (30 in group 1 (70° arthroscope), 17 in group 2 (30° arthroscope)) underwent three-dimensional computed tomography imaging using a grid-based system to measure tunnel position. Results: No difference was found in the accuracy or precision of tunnels (mean position: group 1 = 33.3 ± 6.0% deep-shallow, 27.2 ± 5.2% high-low; group 2 = 31.7 ± 6.9% deep-shallow, 29.0 ± 6.2% high-low; not significant). A post-hoc power analysis suggests a study of 106 patients would be required. Conclusions: This pilot study suggests that tunnel position is not affected by the arthroscope used. An appropriately powered study could investigate this finding alongside other potential benefits of using a 70° arthroscope for this procedure. Trial registration: ClinicalTrials.gov, NCT02816606. Registered on 28 June 2016.This article is freely available via Open Access. Click on the Publisher URL to access it via the publisher's site

The anterolateral ligament of the knee: unwrapping the enigma. Anatomical study and comparison to previous reports.

It has been suggested that the anterolateral ligament (ALL) of the knee may have importance in limiting rotational instability, and reconstruction may prevent a continued pivot-shift following anterior cruciate ligament surgery. However, the anatomy of this ligament has not been consistently reported in recent publications. We describe our experience of cadaveric dissection with reference to other published work.This article is freely available via Open Access. Click on the 'Additional Link' above to access the full-text from the publisher's site.Published (Open Access

Arthroscopic Treatment of Patellar Tendinopathy: Use of 70° Arthroscope and Superolateral Portal

This article is freely available via PubMed Central. Click on the Additional Link above to access the full-text via the publisher's site

Plain radiographs can be used for routine assessment of ACL reconstruction tunnel position with three-dimensional imaging reserved for research and revision surgery.

The position of the osseous tunnels and graft during anterior cruciate ligament (ACL) reconstruction has been the subject of multiple studies aiming for either anatomical placement or an alternative. The assessment of these positions, using post-operative imaging, is therefore of interest to the surgeon in both the evaluation of surgical performance and surveillance of potential complications. The purpose of this review is to identify the optimal use of imaging in both the surveillance of clinical practice and in planning revision surgery

Anterior Cruciate Ligament Mechanoreceptors and their Potential Importance in Remnant-Preserving Reconstruction: A Review of Basic Science and Clinical Findings.

AbstractMechanoreceptors, within the anterior cruciate ligament (ACL), are believed to have importance in proprioception, contributing to dynamic knee stability. The potential for reinnervation of the ACL graft is one of the proposed advantages of remnant-preserving reconstruction. The aim of this review is to summarize advances in the basic science underpinning this function, alongside recent clinical studies, to define the current role for remnant-preservation.A comprehensive systematic review was performed using PubMed and Medline searches. Studies were analyzed with particular focus placed on the methodology used to either identify mechanoreceptors or test proprioception.Contemporary work, using immunohistological staining, has shown mechanoreceptors primarily within proximity to the bony attachments of the ACL (peripherally in the subsynovial layer). The number of these receptors has been shown to decrease rapidly, following rupture, with adhesion to the posterior cruciate ligament slowing this decline. Recent studies have shown proprioceptive deficits, in both the injured and contralateral knees, with the clinical relevance of findings limited by testing methodology and the small differences found. The advantages of remnant-preservation, seen primarily in animal studies, have not been shown in systematic reviews or meta-analysis of clinical studies.The potential for reinnervation of the graft is likely time-dependent and reliant on continued loading of the remnant. Therefore, current clinical use and future research should focus on preserving remnants within 6 months of injury that remain loaded by adherence to the posterior cruciate ligament. Subsequent testing should account for central neurological changes and focus on clinically relevant outcomes.</jats:p

Revisiting the Anterolateral Ligament of the Knee.

Recent research has suggested that the anterolateral ligament (ALL) of the knee may have an important role in preventing persistent rotatory instability following anterior cruciate ligament (ACL) reconstruction.For this review, we performed a thorough literature search and identified the significant steps in the improvement of our understanding. This has progressed from historical reports to accurate characterization of the attachments and dimensions of the ALL through anatomical and histological studies. Alongside this, biomechanical data have demonstrated the role of this structure throughout the range of movement of the knee. Furthermore, the appearance of the ALL on magnetic resonance imaging has been comprehensibly described and radiological markers have been defined as a basis for suggested reconstructive procedures using fluoroscopy.We present a comprehensive review of the evolution of our understanding about this structure. Key advances in our understanding of the dimensions and attachments will guide research into reconstructive options. Further work is needed to determine the biomechanical and clinical outcome of extra-articular reconstruction of the ALL alongside ACL reconstruction.Accepted manuscript - after 12 month embarg

Changes in human articular cartilage following radiofrequency coblation chondroplasty

Aim This study aims to elucidate the effects of radiofrequency chondroplasty (RFC), a surgical technique for the treatment of damaged articular cartilage, at a microscopic scale. Here we report about two aspects of the study – a morphological analysis of the treated surface using nonlinear microscopy and Raman spectroscopy, and an investigation into changes in permeability to large and small molecules. Cartilage samples were obtained from Methods 14 total knee replacement surgeries, which were first treated in vivo with a RFC wand (Arthrocare) using standard arthroscopy technique. Samples for the morphological study were imaged for endogenous fluorescence and collagen, and then imaged using a scanning Raman spectroscope. Samples for the permeability study were incubated in medium containing either Rhodamine or fluorescein labeled albumin, before being sectioned and imaged under a confocal microscope. The morphological study revealed a strong increase in fluorescence in the surface 10 µm, and depletion in collagen signal in the same region, which restores linearly over the adjacent 20–30 µm. Raman spectroscopy showed a spike in β-carrotein in the highly fluorescent surface. Permeability studies show a decrease in permeability to water and an increase in permeability to large molecules, suggesting a remodelling of matrix pores and implications for cell nutrition