Anterior Cruciate Ligament Repair Outcomes: An Updated Systematic Review of Recent Literature

Anterior cruciate ligament primary repair revision rates are increased in skeletally mature patients under the age of 21 compared to reconstruction, while adults (>21 years) show no significant difference: A systematic review and meta-analysis

PURPOSE

To evaluate the impact of age as a risk factor on the revision rates of anterior cruciate ligament (ACL) primary repair (ACLPR), dynamic intraligamentary stabilization (DIS) and bridge-enhanced ACL restoration (BEAR) compared to ACL reconstruction (ACLR).

METHODS

A systematic literature search was performed for comparative studies comparing outcomes for ACLPR, DIS or BEAR to ACLR. A random-effects meta-analysis was performed to assess nondifferentiated and age-differentiated (skeletally mature patients ≤21 and >21 years) ACL revision and reoperation risk, as well as results for subjective outcomes. Methodological study quality was assessed using the Risk of Bias Tool 2.0c and Methodological Index for Nonrandomized Studies tools.

RESULTS

A total of 12 studies (n = 1277) were included. ACLR demonstrated a lower nonage-stratified revision risk at 2 years versus ACLPR, DIS and BEAR, but a similar revision risk at 5 years when compared to DIS. However, an age-stratified analysis demonstrated a significantly increased ACLPR revision risk as compared to ACLR in skeletally mature patients ≤21 years of age (risk ratios [RR], 6.33; 95% confidence interval [CI], 1.18-33.87, p = 0.03), while adults (>21 years) showed no significant difference between groups (RR, 1.48; 95% CI, 0.25-8.91, n.s.). Furthermore, DIS reoperation rates were significantly higher than respective ACLR rates (RR, 2.22; 95% CI, 1.35-3.65, p = 0.002), whereas BEAR (RR, 1.07; 95% CI, 0.41-2.75, n.s.) and ACLPR (RR, 0.81; 95% CI, 0.21-3.09, n.s.) showed no differences. IKDC scores were equivalent for all techniques. However, ACLPR exhibited significantly better FJS (mean difference, 11.93; 95% CI, 6.36-17.51, p < 0.0001) and Knee injury and Osteoarthritis Outcome Score Symptoms (mean difference, 3.01; 95% CI, 0.42-5.60, p = 0.02), along with a lower Tegner activity reduction.

CONCLUSIONS

ACLPR in skeletally mature patients ≤21 years of age is associated with up to a six-fold risk increase for ACL revision surgery compared to ACLR; however, adults (>21 years) present no significant difference. Based on the current data, age emerges as a crucial risk factor and should be considered when deciding on the appropriate treatment option in proximal ACL tears.

LEVEL OF EVIDENCE

Level III.

Anterior Cruciate Ligament Repair-Here to Stay or History Repeating Itself?

Anterior cruciate ligament (ACL) injuries continue to be a prevalent concern among athletes and individuals with an active lifestyle. Traditionally, the standard of care for ACL tears has involved surgical reconstruction using autograft or allograft. This article aims to provide an overview of the evolving landscape of primary ACL repair, examining the current evidence, surgical techniques, patient selection criteria, outcomes, and potential future directions in this field.

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.

Reporting Bias in the Form of Positive Spin Is Highly Prevalent in Abstracts of Systematic Reviews on Primary Repair of the Anterior Cruciate Ligament

PURPOSE

To analyze reporting bias in the form of spin present in systematic reviews and meta-analyses on the topic of primary anterior cruciate ligament (ACL) repair.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were followed throughout this study. Peer-reviewed systematic reviews were collected from 3 databases (PubMed, Scopus, and SPORTDiscus), and their abstracts were assessed for the 15 most common types of spin. Articles were excluded if they were not published in English, had no evidence, were retracted, were published without an abstract, did not have full text available, or included cadaveric or nonhuman subjects. Full text quality was assessed using AMSTAR 2 (A Measurement Tool to Assess Systematic Reviews Version 2). Fisher exact tests were used to examine associations between the different types of spin and other study characteristics such as AMSTAR 2 confidence rating, study design, and level of evidence.

RESULTS

Spin was present in the abstracts of 13 of 15 articles (86.7%). There were significant associations between PRISMA adherence and lower incidences of spin types 3, 6, and 8 (P = .029 for each). A critically low AMSTAR 2 confidence rating was significantly associated with an increased incidence of spin type 9 (P = .01), and a higher AMSTAR 2 score was significantly associated with decreased spin type 4 and type 5 (P = .039 and P = .048, respectively). A more recent year of publication was correlated with a lower incidence of spin type 14 (P = .044).

CONCLUSIONS

Spin is present in most systematic reviews and meta-analyses regarding primary repair of the ACL, with two-thirds of abstracts spinning evidence in favor of ACL repair. Standardized guidelines including the PRISMA guidelines and the AMSTAR 2 assessment tool were negatively correlated with spin. More recently published articles were found to contain significantly less spin, as were articles published in journals with higher Clarivate Impact Factors and Scopus CiteScores.

LEVEL OF EVIDENCE

Level V, systematic review of Level III through V studies.

Correlation between hip muscle strength and the lower quarter Y-balance test in athletes following anterior cruciate ligament reconstruction

INTRODUCTION

The lower quarter Y-balance test (YBT-LQ), which measures dynamic postural control, has been reported to be predictive of lower limb injuries in athletes. It requires subjects to control their body while maintaining a single-leg stance, which necessitates sufficient strength of the hip muscles to maintain stability. The purpose of the study was to investigate the correlation between the performance of the YBT-LQ and the hip abductor or extensor muscle strength in athletes following anterior cruciate ligament reconstruction surgery (ACLR).

METHODS

Fifteen athletes with post-ACLR participated in this cross-sectional study. The participants completed the YBT-LQ, followed by isokinetic measurement of the hip abductor and extensor muscles of both the legs. The peak and average torque of the hip abductor and extensor muscles were tallied with the composite score of the YBT-LQ for each limb.

RESULTS

No correlation was found between the strength of the hip muscles and the YBT-LQ composite score in both injured and non-injured limbs at all velocities except for the eccentric hip abductor and concentric hip extensor torques. The eccentric hip abductor average torque is strongly associated with the YBT-LQ (r = 0.663, p = 0.010) at a speed of 180°/s. The concentric hip extensor peak torque was weakly correlated with balance (r = 0.540, p = 0.046) at a speed of 180°/s.

CONCLUSION

Our study demonstrated a positive correlation between the YBT-LQ and eccentric hip abduction and concentric hip extension at higher velocities. This shows the importance of implementing velocity-oriented rehabilitation in an athletic population following ACLR.

Prospective Comparison of Postoperative Pain and Opioid Consumption Between Primary Repair and Reconstruction of the Anterior Cruciate Ligament

Background

Anterior cruciate ligament (ACL) reconstruction (ACLR) is associated with postoperative pain and necessitates using perioperative nerve blocks and multimodal analgesic plans.

Purpose

To assess postoperative pain and daily opioid use after ACL repair versus ACLR and to assess whether ACL repair could be performed successfully without using long-acting nerve blocks.

Study Design

Cohort study; Level of evidence, 2.

Methods

All eligible patients who underwent ACL surgery between 2019 and 2022 were prospectively enrolled. Patients were treated with primary repair if proximal tears with sufficient tissue quality were present; otherwise, they underwent single-bundle ACLR with either hamstring tendon or quadriceps tendon autograft. The patients were divided into 3 groups: ACLR with adductor canal nerve block (up to 20 mL of 0.25% bupivacaine with 2 mg dexamethasone), primary repair with nerve block, and primary repair without nerve block. Pain visual analog scale and number of opioids used were recorded during the first 14 postoperative days (PODs). Furthermore, patients completed the Quality of Recovery-15 (QoR-15) survey, and range of motion was assessed. Group differences were compared using Mann-Whitney U test and chi-square test.

Results

Seventy-eight patients were included: 30 (39%) underwent ACLR, 19 (24%) ACL repair with nerve block, and 29 (37%) ACL repair without nerve block. Overall, the ACL repair group used significantly fewer opioids than the ACLR group on POD 1 (1 vs 3, P = .027) and POD 2 (1 vs 3, P = .014) while also using fewer opioids in total (3 vs 8, P = .038). This difference was even more marked when only analyzing those patients who received postoperative nerve blocks (1 vs 8, P = .029). Repair patients had significantly higher QoR-15 scores throughout the first postoperative week, and they had greater range of motion (all P < .05). There were no significant differences in pain scores, opioid usage, or QoR-15 scores between patients who underwent repair with versus without nerve block.

Conclusion

The ACL repair group experienced less postoperative pain during the first 2 weeks after surgery and used significantly fewer opioids than the ACLR group. Furthermore, they had improved knee function and higher recovery quality than patients who underwent ACLR during the initial postoperative period. Postoperative nerve blocks may not be necessary after ACL repair.

Distribution of bone tunnel positions and treatment efficacy of bone landmark positioning method for anatomical reconstruction of the anterior cruciate ligament: a case control study

BACKGROUND

This study aimed to investigate the distribution of femoral tunnel and explore the influences of bone tunnel positions on knee functions. The bone landmark positioning method was used to position the femoral tunnel during the anatomical reconstruction surgery in patients with anterior cruciate ligament (ACL) rupture.

METHODS

Data of patients who underwent anatomical reconstruction of the ACL between January 2015 and July 2018, were retrospectively analyzed. The distribution of the femoral tunnel was recorded on 3-D CT after surgery. The tunnel positions were classified into good and poor position groups based on whether the position was in the normal range (24-37% on the x-axis and 28-43% on the y-axis). The Lysholm and IKDC scores, KT-1000 side-to-side difference, pivot shift test and Lachman test results of the knee joints were recorded, and then the differences in knee joint functions between the two groups were analyzed.

RESULTS

84 eligible patients (84 knees) were finally included in this study. Twenty-two and 62 of the patients were categorized in the good and poor position groups, respectively, and the rate of good position was 26.2%. The distribution of bone tunnel was as follows: (x-axis) deep position in 10 patients (12%), normal position in 58 patients (69%), and shallow position in 16 patients (19%); (y-axis) high position in 54 patients (64%), normal position in 26 patients (31%), and low position in 4 patients (5%). 1 year later, the Lysholm and IKDC scores were significantly better in the good position group (P < 0.05), the KT-1000 side to side difference, the pivot shift test and Lachman test results were better in the good position group (P < 0.05).

CONCLUSIONS

The bone tunnels were found to be distributed in and beyond the normal range using the bone landmark method to position the femoral tunnel in the single-bundle anatomical reconstruction of ACL, while the rate of good bone tunnel position was low. The knee joint function scores and stability were lower in patients with poor position of the femoral tunnel.

Clinical Research Progress of Internal Brace Ligament Augmentation Technique in Knee Ligament Injury Repair and Reconstruction: A Narrative Review

Knee ligament injuries are most common in sports injuries. In general, ligament repair or reconstruction is necessary to restore the stability of the knee joint and prevent secondary injuries. Despite advances in ligament repair and reconstruction techniques, a number of patients still experience re-rupture of the graft and suboptimal recovery of motor function. Since Dr. Mackay's introduction of the internal brace technique, there has been continuous research in recent years using the internal brace ligament augmentation technique for knee ligament repair or reconstruction, particularly in the repair or reconstruction of the anterior cruciate ligament. This technique focuses on increasing the strength of autologous or allograft tendon grafts through the use of braided ultra-high-molecular-weight polyethylene suture tapes to facilitate postoperative rehabilitation and avoid re-rupture or failure. The purpose of this review is to present detailed research progress in the internal brace ligament enhancement technique of knee ligament injury repair as well as the reconstruction from biomechanical and histological research and clinical studies and to comprehensively assess the value of the application of this technique.

Failure Rates After Anterior Cruciate Ligament Repair With Suture Tape Augmentation in an Active-Duty Military Population

Background

Anterior cruciate ligament (ACL) repair had previously been considered the standard of care for a ruptured ACL; however, ACL reconstruction has became the standard of care because of poor midterm outcomes after ACL repair. Recently, studies have suggested that the treatment paradigm should shift back to ACL repair.

Purpose/Hypothesis

The purpose of this study was to evaluate the outcomes of ACL repair augmented with suture tape in a high-demand military population. We hypothesized that for proximal ACL avulsions, ACL repair with suture tape augmentation would lead to acceptable failure rates, satisfactory knee stability, excellent functional outcomes, and high rates of return to preinjury activity levels.

Study Design

Case series; Level of evidence, 2.

Methods

Patients who were treated with ACL repair by a single surgeon between March 2017 and June 2019 and who had a minimum of 2 years of follow-up were included. Intraoperatively, all patients first underwent an arthroscopic examination. If an ACL avulsion of the proximal insertion with adequate remaining tissue was visualized, then ACL repair was performed. The primary outcome assessed was ACL repair failure, defined as reruptures or clinical instability requiring revision to ACL reconstruction. Analysis of the risk factors for ACL repair failure was conducted, with age at surgery, sex, body mass index, level of competition, and tobacco use evaluated.

Results

Included were 46 patients (32 male and 14 female; mean age, 28.3 ± 8.4 years) who underwent ACL repair with suture tape augmentation. There were 12 cases of failure (26.1%; 8 male and 4 female). The mean time from injury to surgery in the failure group was 164.1 ± 59.4 days compared to 107.3 ± 98.0 days in the nonfailure group (P = .02). According to multivariate regression analysis, patients aged ≤17 and ≥35 years, elite/competitive/operational patients, and current smokers had a higher chance of ACL repair failure. The mean time to pass a military physical fitness test was 5.0 months. There were no complications other than ACL repair failure.

Conclusion

Primary arthroscopic ACL repair with suture tape augmentation resulted in unacceptably high failure rates at a minimum of 2 years of follow-up in a highly active military population. Age ≤17 and ≥35 years, elite level of competition, time from injury to surgery, and active tobacco use were independent risk factors for ACL repair failure.

Quadriceps Weakness is Associated with Neuroplastic Changes Within Specific Corticospinal Pathways and Brain Areas After Anterior Cruciate Ligament Reconstruction: Theoretical Utility of Motor Imagery-Based Brain-Computer Interface Technology for Rehabilitation

Persistent quadriceps weakness is a problematic sequela of anterior cruciate ligament reconstruction (ACLR). The purposes of this review are to summarize neuroplastic changes after ACL reconstruction; provide an overview of a promising interventions, motor imagery (MI), and its utility in muscle activation; and propose a framework using a brain-computer interface (BCI) to augment quadriceps activation. A literature review of neuroplastic changes, MI training, and BCI-MI technology in postoperative neuromuscular rehabilitation was conducted in PubMed, Embase, and Scopus. Combinations of the following search terms were used to identify articles: "quadriceps muscle," "neurofeedback," "biofeedback," "muscle activation," "motor learning," "anterior cruciate ligament," and "cortical plasticity." We found that ACLR disrupts sensory input from the quadriceps, which results in reduced sensitivity to electrochemical neuronal signals, an increase in central inhibition of neurons regulating quadriceps control and dampening of reflexive motor activity. MI training consists of visualizing an action, without physically engaging in muscle activity. Imagined motor output during MI training increases the sensitivity and conductivity of corticospinal tracts emerging from the primary motor cortex, which helps "exercise" the connections between the brain and target muscle tissues. Motor rehabilitation studies using BCI-MI technology have demonstrated increased excitability of the motor cortex, corticospinal tract, spinal motor neurons, and disinhibition of inhibitory interneurons. This technology has been validated and successfully applied in the recovery of atrophied neuromuscular pathways in stroke patients but has yet to be investigated in peripheral neuromuscular insults, such as ACL injury and reconstruction. Well-designed clinical studies may assess the impact of BCI on clinical outcomes and recovery time. Quadriceps weakness is associated with neuroplastic changes within specific corticospinal pathways and brain areas. BCI-MI shows strong potential for facilitating recovery of atrophied neuromuscular pathways after ACLR and may offer an innovative, multidisciplinary approach to orthopaedic care.

Level of Evidence

V, expert opinion.

Management after acute injury of the anterior cruciate ligament (ACL), part 2: management of the ACL-injured patient

PURPOSE

The aim of this consensus project was to create a treatment algorithm for the management of the ACL-injured patient which can serve as an aid in a shared decision-making process.

METHODS

For this consensus process, a steering and a rating group were formed. In an initial face-to-face meeting, the steering group, together with the expert group, formed various key topic complexes for which various questions were formulated. For each key topic, a structured literature search was performed by the steering group. The results of the literature review were sent to the rating group with the option to give anonymous comments until a final consensus voting was performed. Sufficient consensus was defined as 80% agreement.

RESULTS

During this consensus process, 15 key questions were identified. The literature search for each key question resulted in 24 final statements. Of these 24 final statements, all achieved consensus.

CONCLUSIONS

This consensus process has shown that ACL rupture is a complex injury, and the outcome depends to a large extent on the frequently concomitant injuries (meniscus and/or cartilage damage). These additional injuries as well as various patient-specific factors should play a role in the treatment decision. The present treatment algorithm represents a decision aid within the framework of a shared decision-making process for the ACL-injured patient.

LEVEL OF EVIDENCE

Level V.

Current strategies for enhancement of the bioactivity of artificial ligaments: A mini-review

Background and objective

Anterior cruciate ligament (ACL) reconstruction calls for artificial ligaments with better bioactivity, however systematic reviews regarding bioactivity enhancement strategies, technologies, and perspectives of artificial ligaments have been rarely found.

Methods

Research papers, reviews, and clinical reports related to artificial ligaments were searched and summarized the current status and research trends of artificial ligaments through a systematic analysis.

Results

Having experienced ups and downs since the very first record of clinical application, artificial ligaments differing in material, and fabrication methods have been reported with different clinical performances. Various manufacturing technologies have developed and realized scaffold- and cell-based strategies. Despite encouraging in-vivo and in-vitro test results, the clinical results of such new designs need further clinical examinations.

Conclusion

As the demand for ACL reconstruction dramatically increases, novel artificial ligaments with better osteoinductivity and mechanical performance are promising.

The translational potential of this article

To develop novel artificial ligaments simultaneously possessing excellent osteoinductivity and satisfactory mechanical performance, it is important to grab a glance at recent research advances. This systematic analysis provides researchers and clinicians with comprehensive and comparable information on artificial ligaments, thus being of clinical translational significance.

Comparable Instrumented Knee Joint Laxity and Patient-Reported Outcomes After ACL Repair With Dynamic Intraligamentary Stabilization or ACL Reconstruction: 5-Year Results of a Randomized Controlled Trial

BACKGROUND

Technical innovation has led to the renaissance of anterior cruciate ligament (ACL) repair in the past decade.

PURPOSE/HYPOTHESIS

The present study aimed to compare instrumented knee joint laxity and patient-reported outcomes (PROs) after ACL repair with those after primary ACL reconstruction for acute isolated ACL tears. It was hypothesized that ACL repair would lead to comparable knee joint stability and PROs at 5 years postoperatively in comparison with ACL reconstruction.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

A total of 85 patients with acute ACL tears were randomized to undergo either ACL repair using dynamic intraligamentary stabilization (DIS) or primary ACL reconstruction with a semitendinosus tendon autograft. The primary outcome was the side-to-side difference in anterior tibial translation (ΔATT) assessed by Rolimeter testing at 5 years postoperatively. Follow-up examinations were performed at 1, 2, and 5 years. PROs were assessed using the Tegner activity scale, the International Knee Documentation Committee (IKDC) subjective score, and the Lysholm score. Furthermore, the rates of recurrent instability, other complications, and revision surgery were recorded. A power analysis was performed a priori, and the Friedman test, Mann-Whitney U test, and Bonferroni correction were applied for statistical comparisons with significance set at P < .05.

RESULTS

The mean age at inclusion was 28.3 ± 11.5 years in the ACL repair group and 27.1 ± 11.5 years in the ACL reconstruction group. At 5 years postoperatively, a total of 64 patients (ACL repair: n = 34 of 43 [79%]; ACL reconstruction: n = 30 of 42 [71%]) were available for follow-up. At 5 years, ΔATT was 1.7 ± 1.6 mm in the ACL repair group and 1.4 ± 1.3 mm in the ACL reconstruction group (P = .334). Preinjury PROs were restored as soon as 1 year after surgery and plateaued until 2 and 5 years postoperatively in both groups. At the 5-year follow-up, the mean Lysholm score was 97.0 ± 5.4 versus 94.5 ± 5.5 (P = .322), respectively, and the mean IKDC subjective score was 94.1 ± 9.9 versus 89.9 ± 7.8 (P = .047), respectively, in the ACL repair group versus ACL reconstruction group. At 5 years postoperatively, 12 patients in the ACL repair group (35%; age <25 years: n = 10/12; Tegner score ≥7: n = 10/12) had recurrent instability, of whom 10 underwent single-stage revision ACL reconstruction. In the ACL reconstruction group, there were 6 patients with recurrent instability (20%; age <25 years: n = 6/6; Tegner score ≥7: n = 5/6); however, in 5 patients, staged revision was required. Differences between both groups regarding recurrent instability (P = .09) or ACL revision surgery (P = .118) were not statistically significant. Recurrent instability was associated with age <25 years and Tegner score >7 in both groups.

CONCLUSION

At 5 years after ACL repair with DIS, instrumented knee joint laxity and PROs were comparable with those after ACL reconstruction. Although no significant difference was found between repair and reconstruction, a critical appraisal of the rates of recurrent instability (35% vs 20%, respectively) and revision surgery (38% vs 27%, respectively) is needed. Young age and a high preinjury activity level were the main risk factors for recurrent instability in both groups. However, single-stage revision ACL reconstruction was possible in each case in the ACL repair group. Although ACL reconstruction remains the gold standard in the treatment of ACL tears, the present study supports the use of ACL repair with DIS as a feasible option to treat acute ACL tears in patients aged ≥25 years with low to moderate activity levels (Tegner score <7).

REGISTRATION

DRKS00015466 (German Clinical Trials Register).

Bilateral simultaneous anterior cruciate ligament tears treated with single staged simultaneous primary repair: A case report

Introduction and importance

Simultaneous bilateral anterior cruciate ligament (ACL) injuries are a rare injury pattern within the literature. There is not a consensus optimal management of this injury. Bilateral primary ACL repair in a single stage surgery provides knee stability with a minimally morbid surgery in a single rehabilitation period. This case report offers another option for surgeons to consider in the treatment of this rare injury.

Case presentation

A 45-year-old female skier presented with simultaneous bilateral isolated proximal anterior cruciate ligament injuries. MRI demonstrated bilateral proximal ACL tear patterns which were amenable to primary ACL repair. The patient subsequently underwent acute single-staged arthroscopic primary ACL repair with suture augmentation of both knees. She attained rehabilitation milestones and was fully cleared to return to sporting activities one year post-operatively. Two years post-operatively the patient continues to do well with excellent clinical outcomes.

Clinical discussion

The other treatment modalities reported in the literature were single staged and two staged ACL reconstruction with either autograft or allograft. While single staged procedures are more time and cost efficient, the primary concern is that simultaneous rehabilitation of bilateral ACL reconstructions may lead to severe quadriceps deconditioning. Primary ACL repair poses a potential solution as a minimally morbid surgery with faster rehabilitation from surgery.

Conclusion

Due to the limited invasiveness and morbidity of ACL primary repair with suture augmentation, simultaneous primary repair surgery could be an excellent treatment option for this rare patient population, saving time and cost while providing appropriate knee stability.

Level of evidence

Level IV, Case Report.

•

Single-stage bilateral ACL repair is a viable treatment option in a patient with simultaneous bilateral ACL injuries

•

ACL repair might be an excellent treatment option for this population due to its minimally morbid nature.

•

Simultaneous bilateral ACL repair allows for early return to ambulation and range of motion

Primary repair with suture augmentation for proximal anterior cruciate ligament tears: A systematic review with meta-analysis

PURPOSE

To assess the outcomes of arthroscopic primary repair of proximal anterior cruciate ligament (ACL) tears with suture augmentation in the literature.

METHODS

A systematic search was performed using PubMed, EMBASE, and Cochrane for studies reporting on outcomes of primary repair of proximal ACL tears with suture augmentation between 2015 and 2021. Primary outcomes included failure and reoperation rates, whereas secondary outcomes consisted of functional outcomes. Proportion meta-analysis was performed to assess the overall incidence of failure rates. Outcomes of adults and adolescent were reported separately.

RESULTS

Thirteen studies with 418 patients were included in this study (mean age 32 years, mean follow-up 2.0 years, 49% male). There were no randomized studies and overall grade of recommendation was weak. Overall failure rate for primary repair with suture augmentation was 8% (95% CI 3.9-14.4), but this was higher for younger patients (17%; 95% CI 2.5-63.9) than for older patients (6%; 95% CI 3.8-8.9). The risk for additional reoperations, complications, or hardware removal was low (all <2%), while functional outcomes were good to excellent (all >80% of maximum score).

CONCLUSION

Current literature shows that primary repair with suture augmentation is a reliable treatment option for proximal ACL tears with a failure rate of 8% and good functional outcome scores at short-term follow-up. Although functional outcomes were good irrespective of age, failure rates were higher in young patients (17% vs 6%, respectively). There is a need for high-quality comparative studies with large group of patients to compare these outcomes with ACL reconstruction.

Primary Repair versus Reconstruction in Patients with Bilateral Anterior Cruciate Ligament Injuries: What Do Patients Prefer?

Purpose. The purpose is to evaluate knee preference and functional outcomes of patients with primary anterior cruciate ligament (ACL) repair in one knee and ACL reconstruction in the contralateral side. Methods. All patients who underwent both procedures were retrospectively reviewed at minimum two-year follow-up. Patients were asked to complete questionnaires regarding their operated knees’ preferences during rehabilitation, daily activities, sports activities, and overall function. Furthermore, the Subjective International Knee Documentation Committee, Forgotten Joint Score-12, and Anterior Cruciate Ligament-Return to Sport after Injury were completed. Results. Twenty-one patients were included. All patients underwent ACL reconstruction first, which was displayed at younger age at surgery (24 vs. 33 years, $p=0.010$ ) and longer follow-up (10.2 vs. 2.3 years, $p<0.001$ ), respectively. Thirty-three percent preferred the repaired knee, 11% the reconstructed knee, and 56% had no preference; however, 78% indicated that their repaired knee was less painful during rehabilitation and 83% reported earlier range of motion (ROM) return following repair, which was similar for both knees in 17%. Eighty-three percent of patients indicated better function and progression during rehabilitation with their repaired knee and 11% with their reconstructed knees. No statistical differences were found in patient-reported outcomes between both procedures (all $p>0.4$ ). Objective laxity assessment showed mean side-to-side difference of 0.6 mm between both sides in favor of the reconstructed knee. Conclusion. This study showed that ACL repair and ACL reconstruction lead to similar functional outcomes. However, patients undergoing both procedures may have less pain, earlier ROM return, and faster rehabilitation progression following primary repair.

Failure of primary ACL repair with dynamic intraligamentary stabilization may result in a high risk of two-stage ACL reconstruction: a case series of ten patients

PURPOSE

Dynamic Intraligamentary Stabilization (DIS) is a technique for the repair of acute anterior cruciate ligament (ACL) injuries. The purpose of this study was to investigate the potential challenges of ACL reconstruction (ACLR) following failure of DIS.

METHODS

A retrospective analysis of patients with failure of primary ACL repair performed with DIS was undertaken. Failure was defined as abnormal knee laxity (positive Lachman and/or pivot shift) and/or severely restricted range of motion. Medical and surgical records were reviewed and preoperative standard anteroposterior and lateral X-rays were assessed.

RESULTS

Between July 2015 and May 2022, 10 patients (3 males, 7 females, median age 28 years, range 18-52 years) with failure of DIS were referred to and surgically treated at a single centre. In four patients, single-stage ACLR was performed following the removal of the tibial monoblock. In six patients, arthrofibrosis and excessive tibial tunnel enlargement following the removal of the monoblock prevented single-stage ACLR. These patients underwent arthroscopic arthrolysis and tibial tunnel bone grafting as a first-stage revision procedure.

CONCLUSION

In the present case series, single-stage ACLR was performed in only four (40%) of ten patients following failure of ACL repair with DIS. Arthrofibrosis and excessive tibial tunnel enlargement following the removal of the monoblock prevented single-stage ACLR in six (60%) patients. It is important for clinicians to inform patients that, in the event of failure of ACL repair with DIS, they may run a high risk of undergoing two-stage ACLR.

LEVEL OF EVIDENCE

Level IV, Case Series.

Notchplasty is associated with decreased risk of anterior cruciate ligament graft revision

PURPOSE

Despite influencing knee biomechanics and outcomes, the use of notchplasty at time of anterior cruciate ligament reconstruction (ACLR) has not been evaluated with regards to risk of secondary injury and revision. This study evaluates this association.

METHODS

42 patients (21.7-years, IQR = 19.0-27.5) that underwent primary then revision ACLR at a single institution were contrasted with a case matched control group of patients with grafts that did not fail. Patients were propensity score matched in a 1:2 ratio by age, gender, and date of index procedure. Post-hoc statistical correction was made for post-index procedure sports participation level.

RESULTS

Notchplasty was performed in 2 of 42 cases that went on to revision, and in 31 of 84 cases in the control group (p < 0.001). This was associated with reduced rates of revision ACLR (OR = 0.085, 95%CI = 0.019-0.378). A significant difference was seen in the post-ACLR activity level between groups (p = 0.028), with post-hoc testing highlighting those returning to competitive sport to be more likely to require subsequent revision (OR = 9.647, 95%CI = 1.947-47.795). Notchplasty remained significantly associated with (reduced) risk of revision surgery, despite the observed variation in post-ACLR activity (p = 0.001).

CONCLUSION

Individuals whose graft failed following ACLR were significantly less likely to have had notchplasty performed as part of their surgery than a control group who did not suffer graft reinjury. We propose that this may be due to decreased tensioning of the graft as the knee enters dynamic valgus, which may be of great relevance to athletes undergoing ACLR to enable return to sport.

Returning to Activity After Anterior Cruciate Ligament Revision Surgery: An Analysis of the Multicenter Anterior Cruciate Ligament Revision Study (MARS) Cohort at 2 Years Postoperative

BACKGROUND

Patients with anterior cruciate ligament (ACL) revision report lower outcome scores on validated knee questionnaires postoperatively compared to cohorts with primary ACL reconstruction. In a previously active population, it is unclear if patient-reported outcomes (PROs) are associated with a return to activity (RTA) or vary by sports participation level (higher level vs. recreational athletes).

HYPOTHESES

Individual RTA would be associated with improved outcomes (ie, decreased knee symptoms, pain, function) as measured using validated PROs. Recreational participants would report lower PROs compared with higher level athletes and be less likely to RTA.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

There were 862 patients who underwent a revision ACL reconstruction (rACLR) and self-reported physical activity at any level preoperatively. Those who did not RTA reported no activity 2 years after revision. Baseline data included patient characteristics, surgical history and characteristics, and PROs: International Knee Documentation Committee questionnaire, Marx Activity Rating Scale, Knee injury and Osteoarthritis Outcome Score, and the Western Ontario and McMaster Universities Osteoarthritis Index. A binary indicator was used to identify patients with same/better PROs versus worse outcomes compared with baseline, quantifying the magnitude of change in each direction, respectively. Multivariable regression models were used to evaluate risk factors for not returning to activity, the association of 2-year PROs after rACLR surgery by RTA status, and whether each PRO and RTA status differed by participation level.

RESULTS

At 2 years postoperatively, approximately 15% did not RTA, with current smokers (adjusted odds ratio [aOR] = 3.3; P = .001), female patients (aOR = 2.9; P < .001), recreational participants (aOR = 2.0; P = .016), and those with a previous medial meniscal excision (aOR = 1.9; P = .013) having higher odds of not returning. In multivariate models, not returning to activity was significantly associated with having worse PROs at 2 years; however, no clinically meaningful differences in PROs at 2 years were seen between participation levels.

CONCLUSION

Recreational-level participants were twice as likely to not RTA compared with those participating at higher levels. Within a previously active cohort, no RTA was a significant predictor of lower PROs after rACLR. However, among patients who did RTA after rACLR, approximately 20% reported lower outcome scores. Most patients with rACLR who were active at baseline improved over time; however, patients who reported worse outcomes at 2 years had a clinically meaningful decline across all PROs.

Arthroscopic Anterior Cruciate Ligament Repair Versus Autograft Anterior Cruciate Ligament Reconstruction: A Meta-Analysis of Comparative Studies

Purpose

To compare the clinical outcomes of arthroscopic anterior cruciate ligament (ACL) repair and autograft ACL reconstruction for ACL ruptures.

Methods

PubMed, EMBASE, Scopus, Web of Science and The Cochrane Library were searched for relevant studies from 1 January 1990 to 21 March 2022. Two evaluators independently screened the literature, extracted data and assessed the methodological quality of the enrolled studies. Meta-analysis was conducted using RevMan 5.4 software.

Results

Ten studies with mean follow-up periods from 12 to 36 months were included. For 638 patients with ACL ruptures, arthroscopic ACL repair showed statistically comparable outcomes of failure (p = 0.18), complications (p = 0.29), reoperation other than revision (p = 0.78), Lysholm score (p = 0.78), Tegner score (p = 0.70), and satisfaction (p = 0.45) when compared with autograft ACL reconstruction. A significantly higher rate of hardware removal (p = 0.0008) but greater International Knee Documentation Committee (IKDC) score (p = 0.009) were found in the ACL repair group. The heterogeneity of the side-to-side difference of anterior tibial translation (ΔATT) was high (I²= 80%). After the sensitivity analysis, the I² decreased dramatically (I²= 32%), and the knees with ACL repair showed significantly greater ΔATT (P = 0.04).

Conclusion

For proximal ACL ruptures, arthroscopic ACL repair showed similar clinical outcomes, and even better functional performance when compared to autograft ACL reconstruction. ACL repair has a higher rate of hardware removal, and might be related to greater asymptomatic knee laxity. More high-quality prospective trials are needed to confirm our findings.

Anterior Cruciate Ligament Reconstruction in 107 Competitive Wrestlers: Outcomes, Reoperations, and Return to Play at 6-Year Follow-up

Background

Wrestling is a physically demanding sport, with young athletes prone to anterior cruciate ligament (ACL) injuries. There is a paucity of data evaluating the results of ACL reconstruction (ACLR) in this cohort.

Purpose

To assess return to sport (RTS), patient-reported outcomes, reoperation rates, and graft survival after ACLR in a large cohort of competitive wrestlers at midterm follow-up.

Study Design

Case series; Level of evidence, 4.

Methods

We identified all competitive wrestlers (club, high school, collegiate, or professional) with a history of an ACLR at a single institution between 2000 and 2019. Graft failure was defined as a retear (as determined via clinical or advanced imaging evaluation) and/or revision ACLR. All patients were contacted for determination of reinjury rates; current sport status; and pain visual analog scale, International Knee Documentation Committee, and Tegner activity scores.

Results

Included were 107 knees in 103 wrestlers, with a median follow-up time of 5.9 years (interquartile range [IQR], 3.9-10.3 years). The median age was 17 years (IQR, 15-18 years), with 106 (99%) male patients, and the distribution of bone-patellar tendon-bone (BTB) and hamstring tendon (HT) autografts was 64 (60%) and 43 (40%), respectively. At final follow-up, 80% of athletes were able to RTP at a median of 280 days (IQR, 212-381 days). Graft failure occurred in 14 (13%) knees at a median time of 1.8 years (IQR, 0.7-5.3 years) after the index ACLR. BTB autograft demonstrated a lower failure rate compared with HT autograft (8% vs 21%; P = .044) and was associated with better survival compared with HT autograft up to 15 years after the index ACLR (90.4% vs 76.3%; P = .030). When compared by graft diameter, HT autografts of at least 7.5 mm were not associated with a lower graft failure than BTB constructs of all sizes (P = .205).

Conclusion

Return to competitive wrestling was observed in 80% of athletes after ACLR, with 14% of wrestlers experiencing graft failure. BTB autograft was associated with better survival than HT autograft.

ACL repair for athletes?

Background

The current gold standard treatment for an anterior cruciate ligament (ACL) tear in an athlete is an arthroscopic ACL reconstruction with autografts. This restores the knee stability but is associated with unique complications like graft re-tear, kinesiophobia and graft donor site morbidity. ACL suture repair (ACLSR) is an attractive alternative method of surgical management of this injury.

Current science of ACLSR

The potential advantages of performing a repair are the preservation of native biology and proprioceptive function of ACL, elimination of a graft and preservation of bone stock. The purported benefits are better stability, reduction of kinesiophobia and faster rehabilitation. ACLSR is now performed only for proximal (femoral-sided) tears in the acute phase, when the tissue quality is good and using high-strength nonabsorbable sutures. There are several techniques for performing ACLSR but broadly speaking are either non-augmented, static augmented with suture tape, dynamic augmented or using bio-scaffolds.

Clinical outcome of ACLSR

There is a lot of literature on ACLSRs including case series, cohort studies and randomized controlled trials. The results from these studies are encouraging but mostly pertain to patient reported outcome measures, are in small numbers and in the short-term. The results are also inconsistent across different studies and not specifically performed for the athletic population. Moreover, most of these studies are from the innovator or designer surgeons and groups and have not been independently validated.

Conclusion

Currently, there is insufficient evidence to recommend ACLSR as a preferred method of managing even acute proximal tears in athletes. Improved rates of return to sports, lower retear rate and lesser kinesiophobia needs to be proven in athletes.

Failure and Complication Rates in Common Sports and Arthroscopic Procedures: Reality Check

Expectations following sports medicine and arthroscopic procedures have been elevated because of captivating modern-day media coverage of high-profile athletic injuries, surgery, and rapid return to sports. Unfortunately, this general perception may be misleading, and orthopedic sports medicine physicians must be aware of the harsh reality of the trials and tribulations associated with the subspecialty. The purpose of this review article is to provide an updated brief overview of the complications and failure rates associated with common arthroscopic procedures including rotator cuff repair, biceps tenodesis, Bankart procedure, Latarjet procedure, anterior cruciate ligament reconstruction, anterior cruciate ligament repair, meniscal repair, tibial tubercle osteotomy, and medial patellofemoral ligament reconstruction. Highlighting the complications is the first step toward early recognition, enhancing preventative measures, and successful management.

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.

Current trends in the anterior cruciate ligament part II: evaluation, surgical technique, prevention, and rehabilitation

Clinical evaluation and management of anterior cruciate ligament (ACL) injury is one of the most widely researched topics in orthopedic sports medicine, giving providers ample data on which to base their practices. The ACL is also the most commonly treated knee ligament. This study reports on current topics and research in clinical management of ACL injury, starting with evaluation, operative versus nonoperative management, and considerations in unique populations. Discussion of graft selection and associated procedures follows. Areas of uncertainty, rehabilitation, and prevention are the final topics before a reflection on the current state of ACL research and clinical management of ACL injury. Level of evidence V.

Distal remnant length can be measured reliably and predicts primary repair of proximal anterior cruciate ligament tears

PURPOSE

To assess the reliability and predictive value of quantifying anterior cruciate ligament (ACL) tear location on magnetic resonance imaging (MRI) and assess the predictive value of tear location on the eligibility for arthroscopic primary repair of proximal ACL tears.

METHODS

In this case-control study, all adult patients undergoing acute ACL surgery between 2008 and 2020 were retrospectively reviewed. All patients were treated with the treatment algorithm of undergoing primary repair when proximal tears with sufficient tissue quality were present intraoperatively, and otherwise underwent single-bundle ACL reconstruction. Sagittal MRI images were reviewed to measure proximal and distal remnant lengths along the anterior aspect of the torn ligament, and tear location was calculated as distal remnant divided by total remnant length. Interobserver and intraobserver reliability for remnant measurements were calculated. Then, receiver operating curve analysis (ROC) was performed to calculate the optimal cut-off for the possibility of primary repair with the different measurements.

RESULTS

Two hundred and forty-eight patients were included, of which 151 underwent repair (61%). Inter- and intraobserver reliability ranged between 0.92 and 0.96 [95% confidence interval (CI) 0.55-0.98] and 0.91-0.97 (95% CI 0.78-0.98, respectively). All patients with a tear location of  ≥ 80% on MRI could undergo repair, whereas all patients with tear location of < 60% required reconstruction. The positive predictive value of a proximal quarter tear (≥ 75%) on primary repair was 94%. Older age was correlated with more proximal tear location (p < 0.001), but there was no correlation between tear location and gender, BMI, or timing of surgery (all n.s).

CONCLUSION

This study showed that tear location could reliably be quantified on MRI by assessing distal and proximal remnant lengths. Tear location in the proximal quarter of the ACL was found to have a positive predictive value for repairability of 94%. These findings may assist orthopaedic surgeons in evaluating which patients are eligible for primary ACL repair preoperatively.

LEVEL OF EVIDENCE

III.

REHABILITATION OF NEUROMUSCULAR FUNCTION BY PHYSICAL EXERCISE

ABSTRACT Introduction In long-term sports, especially in explosive sports such as accelerated starting, athletes are prone to rupture the anterior cruciate ligament (ACL). It is the ultimate goal of ACL reconstruction for athletes to restore the stability (static and dynamic) and mechanical structure of the knee joint through reconstruction surgery. Object This article uses ACL reconstruction to repair patients’ ACL and explores the effect of athletes’ nerve recovery after sports. Methods We collected 35 ACL reconstruction athletes and randomly divided them into two groups (experimental group, 18; control group, 17). After reconstruction, the athletes in the experimental group were treated with sports rehabilitation. Results The experimental and control groups had great differences in knee joint exercise indexes and nerve function recovery. Conclusion Sports rehabilitation training can effectively improve the nerve function of the knee joint after ACL reconstruction. Level of evidence II; Therapeutic studies - investigation of treatment results.

Prognostic Factors for Patient-Reported Outcomes at 32 to 37 Years After Surgical or Nonsurgical Management of Anterior Cruciate Ligament Injury

Background:

Knowledge to inform the identification of individuals with a poor long-term prognosis after anterior cruciate ligament (ACL) injury is limited. Identifying prognostic factors for long-term outcomes after ACL injury may inform targeted interventions to improve outcomes for those with a poor long-term prognosis.

Purpose:

To determine whether ACL treatment (early augmented or nonaugmented ACL repair plus rehabilitation, rehabilitation alone, or rehabilitation plus delayed ACL reconstruction [ACLR]) and 4-year measures (quadriceps and hamstrings strength, single-leg hop, knee laxity, flexion and extension deficit, self-reported knee function, activity level) are prognostic factors for patient-reported outcomes at 32 to 37 years after acute ACL injury.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

A total of 251 patients aged 15 to 40 years with acute ACL rupture between 1980 and 1985 were allocated to early ACL repair (augmented or nonaugmented) plus rehabilitation or to rehabilitation alone, based on birth year. One hundred ninety of 234 completed 32- to 37-year follow-up questionnaires (response rate, 81%); 18 people were excluded, resulting in 172 patients available for analysis (mean age, 59 ± 6 years; 28% female). Potential prognostic factors assessed 4 years after ACL injury were ACL treatment (early ACL repair, rehabilitation alone, or delayed ACLR), isokinetic quadriceps and hamstrings strength, single-leg hop performance, knee flexion and extension deficit, knee laxity, Tegner activity scale, and Lysholm score. Outcomes included Knee injury and Osteoarthritis Outcome Score (KOOS) subscales and the Anterior Cruciate Ligament Quality of Life (ACL-QOL) measure. Linear regression adjusted for age, sex, baseline meniscal injury, and contralateral ACL injury was used to assess potential prognostic factors for 32- to 37-year outcomes. Multiple imputation accounted for missing data.

Results:

A fair/poor Lysholm score (vs excellent/good) at 4 years was a prognostic factor for worse KOOS Pain (adjusted regression coefficient, −12 [95% confidence interval (CI), −19 to −4]), KOOS Symptoms (−15 [95% CI, −23 to −7]), KOOS Sport and Recreation (−19 [95% CI, −31 to −8]), and ACL QOL (−9 [95% CI, −18 to −1]) scores. A 4-year single-leg hop limb symmetry index <90% was a prognostic factor for worse KOOS Pain (adjusted regression coefficient, −9 [95% CI, −17 to −1]) and ACL QOL (−13 [95% CI, −22 to −3]) scores at long-term follow-up. A lower activity level, delayed ACLR, and increased knee laxity were prognostic factors in the crude analysis. Rehabilitation alone versus early repair, quadriceps and hamstring strength, and flexion and extension deficit were not related to 32- to 37-year outcomes.

Conclusion:

Reduced self-reported knee function and single-leg hop performance 4 years after ACL injury were prognostic factors for worse 32- to 37-year outcomes. Estimates exceeded clinically important thresholds, highlighting the importance of assessing these constructs when managing individuals with ACL injuries.

Registration:

NCT03182647 (ClinicalTrials.gov identifier).

Diffusion tensor imaging of the anterior cruciate ligament following primary repair with internal bracing: A longitudinal study

Diffusion tensor imaging (DTI) provides information about tissue microstructure and its degree of organization by quantifying water diffusion. We aimed to monitor longitudinal changes in DTI parameters (fractional isotropy, FA; mean diffusivity, MD; axial diffusivity, AD; radial diffusivity, RD) of the anterior cruciate ligament (ACL) following primary repair with internal bracing (IBLA). Fourteen patients undergoing IBLA were enrolled prospectively and scheduled for clinical follow-up, including instrumented laxity testing, and DTI at 3, 6, 12, and 24 months postoperatively. DTI was also performed in seven healthy subjects. Fiber tractography was used for 3D segmentation of the whole ACL volume, from which median DTI parameters were calculated. The posterior cruciate ligament (PCL) served as a control. Longitudinal DTI changes were assessed using a linear mixed model, and repeated measures correlations were calculated between DTI parameters and clinical laxity tests. At follow-up, thirteen patients had a stable knee and one patient sustained an ACL rerupture after 12 months postoperatively. The ACL repair showed a significant decrease of FA within the first 12 months after surgery, followed by stable FA values thereafter, while ACL diffusivities decreased over time returning towards normal values at 24 months postoperatively. For PCL there were no significant DTI changes over time. There was a significant correlation between ACL FA and laxity tests (r = -0.42, P = .017). This study has shown the potential of DTI to longitudinally monitor diffusion changes in the ACL following IBLA. The DTI findings suggest that healing of the ACL repair is incomplete at 24 months postoperatively.

Rupture, reconstruction, and rehabilitation: A multi-disciplinary review of mechanisms for central nervous system adaptations following anterior cruciate ligament injury

BACKGROUND

Despite surgical reconstruction and extensive rehabilitation, persistent quadriceps inhibition, gait asymmetry, and functional impairment remain prevalent in patients after anterior cruciate ligament (ACL) injury. A combination of reports have suggested underlying central nervous system adaptations in those after injury govern long-term neuromuscular impairments. The classic assumption has been to attribute neurophysiologic deficits to components of injury, but other factors across the continuum of care (e.g. surgery, perioperative analgesia, and rehabilitative strategies) have been largely overlooked.

OBJECTIVE

This review provides a multidisciplinary perspective to 1) provide a narrative review of studies reporting neuroplasticity following ACL injury in order to inform clinicians of the current state of literature and 2) provide a mechanistic framework of neurophysiologic deficits with potential clinical implications across all phases of injury and recovery (injury, surgery, and rehabilitation) RESULTS: Studies using a variety of neurophysiologic modalities have demonstrated peripheral and central nervous system adaptations in those with prior ACL injury. Longitudinal investigations suggest neurophysiologic changes at spinal-reflexive and corticospinal pathways follow a unique timecourse across injury, surgery, and rehabilitation.

CONCLUSION

Clinicians should consider the unique injury, surgery, anesthesia, and rehabilitation on central nervous system adaptations. Therapeutic strategies across the continuum of care may be beneficial to mitigate maladaptive neuroplasticity in those after ACL injury.

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.

Reliable Internal Consistency and Adequate Validity of the Forgotten Joint Score-12 after Primary Anterior Cruciate Ligament Repair

Purpose

To validate the Forgotten Joint Score-12 (FJS-12) as a subjective outcome metric for patients undergoing arthroscopic primary anterior cruciate ligament (ACL) repair.

Methods

In this retrospective study, all patients undergoing primary ACL repair for complete isolated proximal tears between 2008 and 2018 were eligible for inclusion. Patients were contacted and asked to complete the FJS-12, Lysholm Knee Score, modified Cincinnati score, Single Assessment Numeric Evaluation (SANE), Subjective International Knee Documentation Committee (IKDC), and Anterior Cruciate Ligament Return to Sport after Injury (ACL-RSI) scale at a minimum of 1 year of follow-up. Internal consistency, convergent validity, and ceiling effects were analyzed.

Results

Ninety-six patients could be included (62%), with a mean FJS-12 score of 86.9 ± 14.0 (range, 31.3-100). The FJS-12 showed reliable internal consistency (Cronbach’s alpha = 0.89). Construct validity was moderate to strong (r = 0. 621-0.702). Ceiling effect for the FJS-12 was 21.9%, which was lower than for the Lysholm (44.6%), modified Cincinnati (45.1%), equal to the IKDC subjective (21.9%), and SANE score (22.0%) but higher compared to the ACL-RSI (12.8%). Furthermore, internal consistency for the other scores was also good to excellent (range Cronbach’s alpha = 0.627-0.953).

Conclusion

The FJS-12 shows high internal consistency and construct validity after primary ACL repair. Furthermore, this metric showed equal or less ceiling effect than most other scores, although still notable. This study suggests that the FJS-12 is an easy and validated outcome metric to evaluate subjective primary repair outcomes.

Level of Evidence

Level III, diagnostic study.

Editorial Commentary: Anterior Cruciate Ligament Suture Repair Could Have High Failure Rates in Active Athletes of All Ages

When it comes to anterior cruciate ligament (ACL) injury and surgery, age is a proxy for early return to strenuous sports. In addition, premature return to sport is a risk factor for reinjury after ACL surgery. Thus, when considering ACL suture repair as an alternative to ACL graft reconstruction, we must consider that failure rates may be influenced by patient demographic variables, particularly age and activity. In the end, treatment options for young patients who are highly active and eager to make a timely return to sport after ACL injury require careful evaluation.

Role of Age on Success of Arthroscopic Primary Repair of Proximal Anterior Cruciate Ligament Tears

PURPOSE

To assess failure rates and patient-reported outcomes measures following arthroscopic primary anterior cruciate ligament (ACL) repair of proximal tears in different age groups.

METHODS

Between 2008 and 2017, the first 113 consecutive patients treated with repair were retrospectively reviewed at minimum of 2 years. Patients were stratified into 3 age groups: ≤21, 22-35, and >35 years. Primary outcomes were ipsilateral reinjury or reoperation, and contralateral injury rates, and secondary outcomes consisted of Lysholm, modified Cincinnati, Single Assessment Numeric Evaluation, International Knee Documentation Committee subjective, pain, and satisfaction scores. Group differences were compared using χ² tests and Mann-Whitney U tests.

RESULTS

Follow-up was obtained in 113 patients (100%). Median age was 35 years (interquartile range [IQR] 23-43) and median follow-up was 2.2 years (IQR 2.0-2.8). Overall, ACL reinjury occurred in 13 patients (11.5%), reoperation in 7 patients (6.2%), complications in 2 patients (1.8%) and contralateral ACL injury in 4 patients (3.5%). Overall, median Lysholm was 95 (IQR 89-100) and International Knee Documentation Committee subjective 92 (IQR 84-99). Treatment failure was significantly greater in the youngest age group (37.0%) as compared with the middle and older groups (4.2% and 3.2%, both P < .005). No significant differences were seen in reoperation, complication, or contralateral injury rates between groups (all P > .2), nor in patient-reported outcomes measures between the groups (all P > .1).

CONCLUSIONS

The failure rate of primary repair of proximal ACL tears is high in patients aged 21 or younger (37.0%), and this should be taken into account when discussing repair in this patient group. In patients older than 21, repair may be an excellent treatment with low failure (3.5%) and complication rates (1.2%) and good subjective scores.

LEVEL OF EVIDENCE

Level III, retrospective comparative therapeutic trial.

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.

Percutaneous Anterior Cruciate Ligament Repair With Needle Arthroscopy and Biological Augmentation

Recent advancements in orthopaedic devices have instilled a renewed interest in repair of the anterior cruciate ligament. Biological augmentation of the repair has also recently been investigated with the hopes of improving repair outcomes and improving biological healing. The advent of needle arthroscopy allows for potentially decreased recovery times and potentially reduced complication rates compared with traditional arthroscopy. The purpose of this article is to present a percutaneous technique to repair the anterior cruciate ligament with suture tape augmentation while also augmenting with the biological byproducts from the native effusion using needle arthroscopy.

Interrater Agreement of an Arthroscopic Anterior Cruciate Ligament Tear Classification System

Background

Anterior cruciate ligament (ACL) rupture is the most common ligament injury treated surgically by orthopaedic surgeons. The gold standard for the treatment of the majority of primary ACL tears is ACL reconstruction. However, novel methods of repair, such as bridge-enhanced ACL repair (BEAR), are currently being investigated as alternatives to reconstruction. To assess patients for midsubstance repair suitability, clarify the prognostic implications of injury location and damage, and evaluate the results of a repair technique, it is important to have a baseline classification system or grading scale that is reproducible across surgeons, particularly for multicenter collaboration. Currently, no such system or scale exists.

Purpose

To develop an arthroscopic ACL tear classification system and to evaluate its interobserver reliability.

Study Design

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

Methods

Eleven fellowship-trained orthopaedic surgeon investigators reviewed 75 video clips containing arthroscopic evaluation of a torn ACL and then completed the 6-question ACL Pathology Evaluation Form. Agreement statistics including exact agreement, Fleiss κ, Gwet agreement coefficient 1 (AC1), and Gwet AC2 were then calculated to assess interobserver reliability.

Results

In aggregate, the multiple assessments of observer reproducibility revealed that surgeon participants in this study, when evaluating the same injury, agreed roughly 80% of the time on whether (1) at least 50% of the tibial footprint remained, (2) the remaining tibial stump was ≥10 mm, and (3) the injury was therefore reparable using the BEAR procedure. Participants also agreed roughly 60% of the time on exactly how many suturable bundles were available. These characteristics are believed to be most important, among those studied, in determining whether a torn ACL is amenable to midsubstance repair.

Conclusion

This study is the first of its kind to demonstrate the interobserver reliability of arthroscopic classification of ACL tears. We have demonstrated that this classification system, though not ideally reproducible, is reliable enough across surgeons at multiple institutions for use in multicenter studies.

Registration

NCT03776162 (ClinicalTrials.gov identifier).

Efficacy of Nonaugmented, Static Augmented, and Dynamic Augmented Suture Repair of the Ruptured Anterior Cruciate Ligament: A Systematic Review of the Literature

BACKGROUND

Anterior cruciate ligament suture repair (ACLSR) was abandoned late last century in favor of anterior cruciate ligament (ACL) reconstruction (ACLR) because of overall disappointing results. However, in recent years there has been renewed and increasing interest in ACLSR for treatment of ACL ruptures. Several contemporary ACLSR techniques are being used, but any difference in effectiveness is unclear.

HYPOTHESIS

Contemporary nonaugmented (NA), static augmented (SA), and dynamic augmented (DA) ACLSR leads to (1) comparable outcomes overall and (2) comparable outcomes between proximal third, middle third, and combined ACL rupture locations (a) within and (b) between ACLSR technique categories.

STUDY DESIGN

Systematic review.

METHODS

An electronic search was performed in the MEDLINE and Embase databases for the period between January 1, 2010, and August 7, 2019. All articles describing clinical and patient-reported outcomes for ACLSR were identified and included, and outcomes for NA, SA, and DA ACLSR categories were compared.

RESULTS

A total of 31 articles and 2422 patients were included. The majority of articles (65%) and patients (89%) reported outcomes of DA ACLSR. Overall, there was high heterogeneity in study characteristics and level as well as quality of evidence (19 level 4; 7 level 3; 3 level 2; and 2 level 1). Most studies indicated excellent patient-reported outcomes. Overall, the variability in (and the maximum of) the reported failure rate was high within all ACLSR categories. The variability in (and the maximum of) the reported rate of all other complications was highest for DA ACLSR. Regarding ACL rupture location, the failure rate was highest in proximal ACL ruptures within the SA and DA ACLSR categories; rates of all other reported complications were highest in combined ACL ruptures within the DA ACLSR category. However, no studies in the NA category and only 1 study in the SA ACLSR category evaluated combined ACL ruptures. The majority of studies comparing ACLSR and ACLR found no differences in outcomes.

CONCLUSION

The amount of high-quality evidence for contemporary ACLSR is poor. This makes it difficult to interpret differences among ACLSR categories and among ACL rupture locations and, though promising, to establish the role of ACLSR in the treatment of ACL ruptures. More high-quality large randomized clinical trials with longer follow-up comparing ACLSR and ACLR are needed.

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.

Large variation in indications, preferred surgical technique and rehabilitation protocol for primary anterior cruciate ligament repair: a survey among ESSKA members

PURPOSE

To assess current surgical preferences and practice patterns regarding primary anterior cruciate ligament (ACL) repair among European Society for Sports Traumatology, Knee Surgery and Arthroscopy (ESSKA) members.

METHODS

A web-based survey was designed, including questions regarding indications for primary repair, outcomes of primary repair, and rehabilitation protocols. An invitation for study participation was sent by email to all ESSKA e-mail contacts. Descriptive statistics were performed.

RESULTS

A total of 169 surgeons responded to the survey (7% response rate of active members). Lack of supporting scientific evidence is the main reason for not using repair as a surgical treatment (63%). Most important indications were proximal avulsion tears (84%), younger age (49%), and older age (34%). Among those currently utilizing repair as a treatment option, transosseous tunnel fixation repair (34%) and repair with internal brace using transosseous tunnel fixation (32%) were the most preferred techniques. Eleven percent indicated dynamic intraligamentary stabilization as their preferred technique. A similar rate of progression for rehabilitation for repair and reconstruction techniques was noted among respondents.

CONCLUSION

This practice survey shows that the majority of surgeons indicated the main reason for not incorporating primary repair in their current practices was a lack of supporting scientific evidence. Among those holding favourable attitudes and beliefs, most surgeons indicated patients with proximal tears, younger-aged, and older-aged patients might be eligible for repair. Prospective studies with higher levels of evidence are warranted to establish guidelines for repair, including indications, optimal surgical technique, and rehabilitation protocols.

LEVEL OF EVIDENCE

V (expert opinion).

Tissue-Engineered Decellularized Allografts for Anterior Cruciate Ligament Reconstruction

Anterior cruciate ligament (ACL) reconstruction with allografts is limited by high immunogenicity, poor cellularization, and delayed tendon-bone healing. Decellularized tendons (DAs) have been used as bioscaffolds to reconstruct ligaments with variable success. In the study, four kinds of decellularized allogeneic hamstring tendons were prepared and their microstructure and cytocompatibility were examined in vitro. The results showed that decellularized allografts neutralized by 5% calcium bicarbonate had typical reticular and porous microstructures with optical cytocompatibility. Tissue-engineering decellularized allografts (TEDAs) were prepared with the selected decellularized allografts and tendon stem/progenitor cells and used for ACL reconstruction in a rabbit model. Histological staining showed that the TEDAs promoted cellular infiltration and new vessel formation significantly and improved tendon-bone healing moderately compared to decellularized allografts. Better macroscopic scores and biomechanical results were observed in TEDA groups, but there were no significant differences between DA and TEDA groups at months 1, 2, and 3 postoperatively. Immunohistochemical data showed that the tissue-engineering decellularized allografts enhanced the expression of collagen I at each timepoint and collagen III at months 1 and 2. ELISA analysis showed that the tissue-engineering decellularized allografts reduced the secretion of IgE and IL-1β within 1 month and promoted the secretion of IL-2, IL-4, IL-10, and IL-17 after 1 month. The results showed that tissue-engineering decellularized allografts strengthened intra-articular graft remodeling significantly and provided moderate improvements in tendon-bone healing by creating more suitable immune responses than decellularized allografts. The study revealed that tissue-engineering decellularized allografts as a promising option for ACL reconstruction could achieve more favorable outcomes.

The vancomycin soaking technique: no differences in autograft re-rupture rate. A comparative study

PURPOSE

The main aim of this study was to evaluate the re-rupture risk after an anterior cruciate ligament reconstruction (ACL-R) using the vancomycin soaking technique and to compare it with the re-rupture risk in patients on whom this technique was not utilized. The secondary purpose was to compare the functional outcomes of those two subsets of patients operated on for ACL-R. The hypotheses are that the vancomycin soaking technique does not affect the re-rupture risk or the functional outcomes.

MATERIAL AND METHODS

A retrospective historical cohort study was conducted. Two groups were compared in terms of the re-rupture rate (traumatic or atraumatic) and functional outcomes (International Knee Documentation Committee (IKDC), Tegner, and Lysholm). Group 1 consisted of patients that received pre-operative IV antibiotics. In group 2, the patients received pre-operative IV antibiotics along with a graft that had been presoaked in a vancomycin solution. A minimum follow-up of five years was required.

RESULTS

There were 17 patients that suffered a re-rupture in group 1 (4.7%) and 15 in group 2 (3.9%) (n.s.). IKDC was 82.0 in group 1 and 83.9 in group 2 (p = 0.049); Tegner scored 4 in both groups (n.s.) and Lysholm was 90.3 in group 1 and 92.0 in group 2 (p = 0.015).

CONCLUSION

The vancomycin soaking technique for ACL autografts is a safe procedure for the daily clinical practice, in terms of re-ruptures. Moreover, it does not impair functional outcomes after an ACL-R.

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.

Return to sports following arthroscopic primary repair of the anterior cruciate ligament in the adult population

BACKGROUND

To assess return to sport (RTS) rates and evaluate the timeline of rehabilitation milestones following arthroscopic primary anterior cruciate ligament (ACL) repair.

METHODS

A retrospective review of all patients treated with primary repair between 2008 and 2018 was conducted. All adult patients with preoperative Tegner of ≥6 and minimum follow-up of two years were included. Patients were seen in clinic or contacted to complete the postoperative Tegner, and report their time to return to work, time to running, and time to RTS. Additionally, they were asked to complete the ACL-Return to Sport After Injury (ACL-RSI). Outcomes were compared using Mann-Whitney U tests and chi-square tests.

RESULTS

Sixty patients treated with repair were included, of which 85% returned to any sports, 70% returned to knee-strenuous sports, and 60% returned to preinjury level. Patients returned to work in seven days (IQR five to 14 days), running in 90 days (IQR 57-120 days), and sports in 180 days (IQR 116-270 days). Overall, ACL-RSI score was 80.0 (IQR 53.0-95.0). Higher return to preinjury rates was found in patients with older age and lower fear of reinjury (all p < .05).

CONCLUSION

Following primary ACL repair, 70% of adult patients returned to knee-strenuous sports and 60% to preinjury levels by 180 days postoperatively. Positive predictors for return to preinjury levels included older age and low fear of reinjury.

LEVEL OF EVIDENCE

Retrospective Case-Series, level IV.

AANA20: The 2020 Annual Meeting of the Arthroscopy Association of North America

Arthroscopy, Arthroscopy Techniques, and Arthroscopy, Sports Medicine, and Rehabilitation will be in attendance in force at the 2020 Annual Meeting of the Arthroscopy Association of North America (AANA20). Program highlights and innovations include surgery simulcasts, "Great Debates," award-winning papers, Feature Lectures, and sessions glimpsing what is On the Horizon-and perhaps over and beyond.