Anterior cruciate ligament (ACL) repair using cortical or anchor fixation with suture tape augmentation vs ACL reconstruction: A comparative biomechanical analysis

ACL Repair with Suture Tape Augmentation of Proximal Tears and Early ACL Reconstruction with Suture Tape Augmentation Result in Comparable Clinical Outcomes to ACL Reconstruction at 2-year Follow-up

PURPOSE

The purpose of this study is to compare the post-operative side-to-side laxity and short-term clinical outcomes of patients who received primary ACL repair with suturetape augmentation, acute ACL reconstruction with suture tape augmentation performed within 8 weeks of injury (ACLRacute), or ACL reconstruction (ACLR) beyond 8 weeks of injury.

METHODS

Following IRB approval, 100 patients were enrolled in this prospective trial: n=34 primary ACL repair with suture tape augmentation, n=33 ACL reconstruction performed within 8 weeks of injury (ACLRacute), and n=33 ACL Reconstruction (ACLR). Patients were allocated to ACL repair if a proximal avulsion was present with good tissue quality (Sherman type 1), confirmed by intraoperative diagnostic arthroscopy. Preoperative side-to-side AP knee laxity was assessed with KT-1000 arthrometer and patient-reported outcomes (PROs) including visual analog scale (VAS), Marx activity scale, Veterans RAND 12-item health survey (VR-12 physical & mental), Single Assessment Numeric Evaluation (SANE), Knee Injury and Osteoarthritis Outcome Score (KOOS) survey subscales, and range of motion (ROM) were collected. These objective and subjective measures were repeated at regular intervals post-operatively through 2 years. Minimal clinically important differences (MCID) calculations were performed assessing post-operative PRO changes at 2 years compared to preoperative.

RESULTS

The average time from injury to surgery was 5.03±1.2 weeks for the ACL repair group, 5.09±0.74 weeks for the ACLRacute, and 43.22±33.5 weeks for the ACLR group. Postoperatively, the KT-1000 side-to-side laxity difference for 30lbs was determined to be 0.1±0.37, 95% CI: [-0.7,0.8] for ACL repair vs ACLR (p<0.0001), -0.8±0.35, 95% CI: [-1.5,-0.1] for ACLRacute vs ACLR (p<0.0001), and 0.8±0.40, 95% CI: [0.0,1.6] for ACL repair vs ACLRacute (p<0.0001). The data reveals ACL repair and ACLRacute are non-inferior to ACLR at 2-year follow-up. The post-operative difference from baseline for all PROs demonstrated improvement for all PROs. MRI at 1-year revealed tissue healing for the three ACL injury treatment groups.

CONCLUSION

Patients who underwent ACL repair of proximal tears with suture tape augmentation or ACL reconstruction within 8 weeks from injury resulted in non-inferior side-to-side knee laxity, comparable PROs, and similar range of motion at 2-year follow-up, compared to ACL reconstruction.

Editorial Commentary: Noninferiority of Anterior Cruciate Ligament Repair With Dynamic Intraligamentary Stabilization at Short- to Mid-Term Follow-Up Does Not Justify Superseding Anterior Cruciate Ligament Reconstruction as the "Gold Standard" for Anterior Cruciate Ligament Surgery

With advances in surgical technology, including the introduction of some kind of mechanical augmentation, there has been a resurgence of interest in primary repair of the anterior cruciate ligament (ACL). If successful, ACL repairs may provide several advantages over reconstruction resulting from the preservation of the native anatomy and proprioception. Recently, augmentation of ACL repair using dynamic intraligamentary stabilization (DIS) has been proposed, to create an optimal biomechanical environment for healing. In the DIS technique, an additional nonresorbable cord is placed along the ACL and attached to a dynamic spring fixed in the proximal tibia, keeping the tibia in a posterior drawer position at every degree of flexion. The analyzed randomized controlled trials comparing ACL repair with DIS to ACL reconstruction found overall similar failure and revision rates, whereas the few observed statistically significant differences in functional scores or knee stability favoring either of the techniques were clearly not clinically relevant. Of course, repair of a torn ACL should be limited to a specific subset of patients presenting with an acute femoral avulsion tear with minimal retraction and good tissue quality. However, the present short- to mid-term results do not justify ACL reconstruction to be superseded by ACL repair with DIS as the "gold standard" for surgical treatment of ACL tears in the future, even in this subset of patients.

Objective Clinical Measurement Tools for Functional Evaluation of the Surgical Patient

Following knee surgery, clinicians have traditionally used visually rated or time-based assessments of lower extremity movement quality to measure surgical outcomes, plan rehabilitation interventions, and measure success. These methods of assessment are prone to error and do not fully capture a patient's inefficient movement patterns post surgery. Further, currently available systems which objectively measure kinematics during these tasks are expensive and unidimensional. For these reasons, recent research has called for the development of objective and low-cost precision rehabilitation tools to improve clinical measurement of movement tasks. The purpose of this article is to highlight two such tools and their applications to knee surgery. The systems highlighted within this article are the Mizzou Point-of-Care Assessment System (MPASS) and the Mizzou Knee Arthrometer Testing System (MKATS). MPASS has demonstrated high levels of agreement with the gold-standard Vicon system in measuring kinematics during sit-to-stand (R > 0.71), lateral step-down (intraclass correlation coefficient [ICC] > 0.55, apart from ankle flexion), and drop vertical jump tasks (ICC > 0.62), as well as gait (R > 0.87). MKATS has been used to quantify differences in tibiofemoral motion between groups during lateral step-down, step-up-and-over, and step-up/step-down tasks. Objective measurement of clinical tasks using portable and inexpensive instruments, such as the MPASS and MKATS, can help clinicians identify inefficient movement patterns and asymmetries which may damage and wear down supporting structures within the knee and throughout the kinetic chain causing pain and discomfort. Identifying these issues can help clinicians to plan interventions and measure their progress at a lower cost than currently available systems. The MPASS and MKATS are useful tools which have many applications to knee surgery.

Anterior Cruciate Ligament Repair Augmented With Dynamic Intraligamentary Stabilization Is Equivalent to Hamstring Autograft Reconstruction at Short- and Mid-Term Follow-Up: A Systematic Review

PURPOSE

To compare clinical outcomes, knee stability and complications, failure, and revision rates after anterior cruciate ligament repair (ACLr) with dynamic intraligamentary stabilization (DIS) versus anterior cruciate ligament reconstruction (ACLR) with hamstring autograft for primary ACL ruptures at short and mid-term follow-up.

METHODS

A Preferred Reporting Items for Systematic Reviews and Meta-Analyses-compliant systematic review of PubMed/MEDLINE and Scopus was performed. Studies that evaluated patients undergoing ACLr with DIS or ACLR with hamstring autograft were considered for inclusion. Studies were excluded if patients were affected by concomitant meniscal, ligamentous, or chondral injuries needing surgical treatment, because of their potential confounding effect on postoperative outcomes. The Risk of Bias-2 tool was used to assess the risk of bias in the included studies. The quality of available evidence was rated according to Grading of Recommendations Assessment, Development, and Evaluation recommendations. The study protocol was registered in the PROSPERO database (ID: CRD42023394558).

RESULTS

Five randomized controlled trials comparing the outcomes of ACLr with DIS versus ACLR with hamstring autograft met the inclusion criteria. No major differences in terms of patient-reported outcomes (International Knee Documentation Committee subjective form, Lysholm score, Tegner activity scale, Knee injury and Osteoarthritis Outcome Score, visual analog scale satisfaction) or rates of complications, revisions, and failures were found in included studies at all time points. Repair showed greater International Knee Documentation Committee subjective form scores at 5 years in one study, whereas ACLR displayed significantly increased knee stability at 6 months and 5 years in 2 different studies, although the clinical relevance of these differences is doubtful.

CONCLUSIONS

The results of this study suggest that ACLr with DIS is not inferior to ACLR with hamstring autograft in terms of rates of clinical outcomes, knee stability, risk of failure, complications, and revision surgery. Therefore, ACLr with DIS may be a viable alternative to ACLR with hamstring autograft in selected patients.

LEVEL OF EVIDENCE

Level I, systematic review of Level I studies.

Comparative efficacy and safety of different surgical approaches for the treatment of anterior cruciate ligament injury: a Bayesian network meta-analysis protocol

INTRODUCTION

Anterior cruciate ligament (ACL) rupture can be treated surgically or non-surgically, with several surgical interventions available at present. However, the comparatively effective surgical intervention with relatively fewer side effects remains unknown. This study aims to fill in this gap by conducting a Bayesian network meta-analysis (NMA) and provide a theoretical basis for the clinical application.

METHOD AND ANALYSIS

We will perform a Bayesian NMA and will include randomised controlled trials (RCTs) published in English or Chinese that compare surgical intervention (ie, standard ACL reconstruction, ACL remnant-preserving reconstruction and ACL repair with suture augmentation to conservative therapy or studies that compare one surgical intervention to another for the symptom relief and function recovery of patients with ACL rupture. Primary outcome will be the proportion of patients with symptomatic and functional improvement measured by the Knee Injury and Osteoarthritis Outcome Score before and 6 months after treatment, with scores ranging from 0 (worst) to 100 (best). Secondary outcomes will be knee-specific quality of life (ACL QoL), return to activity and level of sport participation (Tegner or modified Tegner score), health-related QoL (EuroQol Group 5-Dimension 5-Level, EQ-5D-5L), resource use, intervention-related complications and patient satisfaction. We have developed search strategies for PubMed, Embase, the Cochrane Library and Web of Science, retrieving RCTs that meet the inclusion criteria from database inception to 1 December 2023. The methodological quality of the included RCTs will be assessed based on the Cochrane risk of bias table. The relative ranking probability of the best intervention will be estimated using the surface under the cumulative ranking curve. The Bayesian NMA will be conducted by using WinBUGS V.1.4.3. The Grading of Recommendations Assessment, Development and Evaluation approach will be applied to determine our confidence in an overall treatment ranking from the NMA.

ETHICS AND DISSEMINATION

Ethical approval for this study is not required because no private or confidential patient data will be used in this study. Findings of this study would be disseminated through the publication in a peer-reviewed medical journal.

PROSPERO REGISTRATION NUMBER

CRD42023437115.

Suture Anchor Technique for Bridge Enhanced Anterior Cruciate Ligament Restoration

Anterior cruciate ligament (ACL) injuries are common in the athletic population. ACL repair with bridge enhancement is an emerging technology with promising clinical outcomes in patients with a proximal to midsubstance ACL tears. Currently, there are a variety of fixation methods described for isolated ACL repair, including suspensory and anchor techniques. This Technical Note describes a bridge enhanced ACL restoration procedure technique, using suture anchors for the femoral fixation. Advantages of this technique include more rigid fixation and avoiding need for accessory over-the-top incision. Additionally, the surgical workflow is more similar to an ACL reconstruction with intra-articular screw fixation, which may be more readily adopted by some surgeons.

Arthroscopic Anatomic Anterior Cruciate Ligament Primary Repair Restores Anterior Tibial Translation Intraoperatively at Time Zero With No Additional Effect of Suture Augmentation

PURPOSE

To intraoperatively evaluate the ability of anterior cruciate ligament (ACL) primary repair (ACLPR) to restore anterior tibial translation (ATT) at time zero and to assess the influence of additional suture augmentation (SA) on ATT.

METHODS

Patients with proximal ACL tears undergoing arthroscopic ACLPR with dual-suture anchor fixation were included in this time-zero clinical study. Laxity measurements were taken with a digital arthrometer to evaluate ATT stability preoperatively in the office (T0) as a standardized diagnostic tool, preoperatively under anesthesia (T1), at time zero intraoperatively after ACLPR but prior to SA fixation (T2), and after SA fixation (T3).

RESULTS

A total of 27 patients (mean age ± standard deviation [SD], 35.1 ± 12.0 years) with proximal ACL tears and significant preoperative (T0) ATT side-to-side differences (SSDs) (mean ± SD, 4.1 ± 1.5 mm) were evaluated. ACLPR was shown to restore ATT SSD at time zero (mean ± SD, 0.2 ± 1.1 mm) given that a significant reduction in ATT SSD (mean difference ± standard error, -4.7 ± 0.21 mm; P < .001) was achieved when comparing preoperative and intraoperative measurements after separate refixation of both ACL bundles with suture anchors. Additional SA fixation did not further decrease ATT when comparing measurements of the ipsilateral leg after ACL refixation and after SA fixation (mean difference ± SD, 0.03 ± 0.22 mm; P = .496).

CONCLUSIONS

ACLPR with dual-suture anchor fixation restores time-zero ATT laxity in adults with proximal ACL tears. Additional SA fixation in full knee extension does not further decrease ATT.

CLINICAL RELEVANCE

This study provides important information about the effectiveness of ACLPR in restoring ATT. SA with the knee fixed in full knee extension does not further decrease ATT; therefore, augmentation may not lead to overconstraint of the knee or stress shielding of the repaired ACL.

Stabilization and Gap Formation of Adjustable Versus Fixed Primary ACL Repair With Internal Brace: An in Vitro Full-Construct Biomechanical Cadaveric Study

Background

A knotless, tensionable primary anterior cruciate ligament (ACL) repair system preloaded with an internal brace has been released. Currently, there is no biomechanical data on the stabilization and gap formation behavior of the adjustable system when compared with fixed repairs in human ACL tissue.

Hypothesis

That knotless adjustable suture repair with an internal brace would provide overall higher construct stability and greater load share on the ACL with less gap formation compared with fixed repair.

Study Design

Controlled laboratory study.

Methods

Human cadaveric knees were utilized for internal braced ACL repair constructs (each group n = 16). Two fixed groups consisting of a single-cinch loop (SCL), cortical button (SCL group), and knotless suture-anchor (anchor group) were compared with an SCL-adjustable loop device (SCL-ALD) group. Testing was performed at 4 different peak loads (50, 150, 250, 350 N) over 4000 cycles at 0.75 Hz including suture repair preconditioning (10 cycles at 0.5 Hz) for SCL-ALD. Specimens were ultimately pulled to failure with a cut internal brace. The final loading situation of the construct and ACL repair with gap formation and ultimate strength were evaluated.

Results

Peak elongation at various peak loads showed a significantly higher (P < .001) stabilization of SCL-ALD when compared with both fixed groups. There was a significantly higher (P < .001) load share of SCL-ALD, especially at lower loads (48% of 50 N), and the gap formation remained restricted up to 250 N. With only a little load share on the fixed constructs (<6%) at lower loads (50, 150 N), gap formation in these groups started at a load of 150 N, leading to significantly higher gaps (P < .001). The ultimate failure load for SCL-ALD and anchor groups was significantly increased (P < .001) as compared with SCL. The stiffness of SCL-ALD (62.9 ± 10.6 N/mm) was significantly increased (P < .001).

Conclusion

Internal braced knotless adjustable fixation for ACL repair with preconditioning of the suture repaired ligament increased the overall stabilization with higher load share on the ACL and restricted gap formation (<0.5 mm up to 350 N) compared with fixed suture repair. All internal braced repairs restored stability according to native ACL function.

Clinical Relevance

Adjustable ACL repair improved the mechanical characteristics and reduced gap formation, but the overall clinical significance on healing remains unclear.

Postless Tape Augmentation for Anterior Cruciate Ligament (ACL) Reconstruction

Suture or tape augmentation for anterior cruciate ligament (ACL) reconstruction has been described as a technique to increase biomechanical strength and potentially improve clinical outcomes. However, the suture or tape used for augmentation usually requires independent tibial fixation from the ACL graft in the form of an anchor or post. This may introduce the potential for graft and augment tension mismatch, while increasing surgical cost. We present our technique for ACL reconstruction with postless tape augmentation. The ACL graft and tape are fixed at the same tension with interference fixation using a single tibial sheath and screw construct, which allows for ACL augmentation without the need for an additional post or implant.