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

Anterior Cruciate Ligament Repair Results in Similar Patient Reported Outcome Measures as Anterior Cruciate Ligament Reconstruction: A Systematic Review of Prospective Comparative Studies

PURPOSE

To investigate the patient-reported outcomes (PROs), knee stability, and complications in prospective comparative studies of patients undergoing augmented anterior cruciate ligament (ACL) repair compared to ACL reconstruction (ACLR).

METHODS

A literature search was performed according to the 2020 PRISMA guidelines. Human clinical studies of level I-II evidence comparing PROs, knee stability and complications following ACL repair and reconstruction were included, and a qualitative analysis was performed. Excluded studies included those lacking reporting outcomes, studies that performed open ACLR or repair, studies published prior to the year 2000 and studies with evidence levels III-IV. Study quality was assessed using the Cochrane Collaboration's risk of bias tool.

RESULTS

Seven level of evidence I-II studies were retained including 190 ACLR and 221 repairs (75 Bridge-Enhanced ACL Repair (BEAR), 49 Suture Augmentation (SA), and 97 Dynamic Intraligamentary Stabilization (DIS)). At final follow-up, re-rupture rates varied between 0-14% (BEAR) vs 0-6% (ACLR) and mean side-to-side differences measured using KT-1000 testing ranged from 1.6-1.9mm (BEAR) vs 1.7-3.14mm (ACLR). For DIS vs ACLR, mean anterior tibial translation values at final follow-up were 1.7mm (DIS) vs. 1.4mm (ACLR), and re-rupture rates ranged from 20.8%-29% (DIS) vs. 17%-27.2% (ACLR). For SA vs ACLR, the mean side to side difference ranged from 0.2-0.39mm (SA) vs 0.33-0.4mm (ALCR), while the re-rupture rates were 10% (SA) vs. 0% (ACLR). International Knee Documentation Committee (IKDC), Tegner, Lysholm and Knee Injury and Osteoarthritis Outcome (KOOS) scores across both cohorts exhibited statistically significant, and comparable improvement, from baseline to final follow-up ranging from 1 to 5 years.

CONCLUSION

Augmented ACL repair results in similar patient reported outcomes measures in comparison to ACL reconstruction. However, augmented ACL repair may be associated with higher rates of failure given re-rupture rates of up to 14%, 29% and 10% for BEAR, DIS and SA, respectively.

LEVEL OF EVIDENCE

II; Systematic review of level I-II studies.

ACL reconstruction demonstrates better stability compared to ACL repair for patients with Schenck III and IV knee dislocations

PURPOSE

This study compared mid-term outcomes of two anterior cruciate ligament (ACL) restoration techniques within an early total surgical care of acute knee dislocation: repair with additional internal bracing (ACLIB) and reconstruction with autograft (ACLR). Initial results at 12 months demonstrated that ACLR offered superior stability compared to ACLIB.

METHODS

Retrospective clinical study of patients with acute type III or IV KD. ACLIB or ACLR procedures were performed accompanied by simultaneous suture and internal bracing of the posterior cruciate ligament (PCL) and repair with lateral augmentation of the medial and lateral complex injuries utilizing Arciero's reconstruction technique. Patient-reported outcome measurements (PROMs), instrumental stability assessment via the Rolimeter-Test, and stress radiographs were analyzed.

RESULTS

The study involved 20 patients (5 IIIM, 5 IIIL, and 10 IV injuries) with an average follow-up of 35.2 ± 7.4 months. Notable differences in anterior tibial translation on stress radiography favouring ACLR persisted at 24-month follow-up in side-to-side difference (SSD) (ACLIB 2.8 ± 2.5 mm vs. ACLR 0.3 ± 2.6 mm; p = 0.0487), but Rolimeter test variance diminished (SSD ACLIB 2.5 ± 0.9 mm vs. ACLR 1.8 ± 1.7 mm). Both groups showed excellent PROMs (Lysholm Score: ACLIB 84.4 ± 15.8 vs. ACLR 89.9 ± 9.0; IKDC Score: ACLIB 77.1 ± 16.2 vs. ACLR 77.7 ± 8.6).

CONCLUSION

Our results indicate improved anterior stability at 12 months, which persisted at 24 months after ACL reconstruction compared with ACL repair by stress radiography. Both groups showed favourable patient-reported outcomes throughout the follow-up period. Notable rates of postoperative knee stiffness were observed in both groups. These were successfully managed with early, one-time arthroscopic arthrolysis within the first seven months of treatment, resulting in no major range of motion limitations at the 24-month follow-up.

LEVEL OF EVIDENCE

Retrospective cohort study, III.

All-Inside Anterior Cruciate Ligament Reconstruction Had Clinical Outcome Similar to the Transtibial Technique Except for Improved Side-to-Side Difference and Tegner Activity Scale: A Systematic Review and Meta-analysis

PURPOSE

To compare clinical outcomes of the all-inside technique with the transtibial technique in anterior cruciate ligament reconstruction based on available literature on this topic.

METHODS

According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist, we conducted a systematic search for randomized controlled trials and cohort studies. Our comprehensive search encompassed PubMed, Embase, Cochrane Library, and Web of Science. We included randomized controlled trials (RCTs) and cohort studies that compared the 2 techniques with a minimal 1-year follow-up. Two independent authors assessed RCTs using the risk of bias tool developed by the Cochrane Collaboration and evaluated the quality of cohort studies using the Newcastle-Ottawa Scale for Assessing the Quality of Nonrandomized Comparative Trials. The subjective and objective outcomes, complications, and graft failure were obtained. R software was used to perform the analysis.

RESULTS

The present analysis enrolled 9 RCTs (n = 687) and 11 cohort studies (n = 910). After a minimal 1-year follow-up in RCTs, functional outcomes such as International Knee Documentation Committee (IKDC) subjective score, Lysholm score, Tegner activity scale, Knee Society Score, and hop test were found to be similar between 2 techniques. The laxity outcomes, including the IKDC objective grade and pivot-shift test, were suggested to be comparable. There was a significant difference favoring the transtibial technique in terms of side-to-side difference (P = .04; 95% confidence interval [CI], 0.08-0.90). The pooled data from cohort studies indicated equivalent results in terms of IKDC subjective score, Lysholm score, side-to-side difference, IKDC objective grade, complications, and graft failure, with the exception of statistical difference in the Tegner activity scale (P = .03; 95% CI, -0.50 to -0.04).

CONCLUSIONS

Our findings suggest that there is no difference in most outcome scores between the all-inside and transtibial techniques for anterior cruciate ligament reconstruction. There are statistically significant differences in side-to-side difference and Tegner activity scale favoring the all-inside technique.

LEVEL OF EVIDENCE

Level IV, meta-analysis of Level I to IV studies.

Incidence of Osteoarthritis Between ACL Reconstruction With Different Graft Types and Between ACL Reconstruction and Repair: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Background

Variation in stiffness, fixation methods, and donor-site morbidity after anterior cruciate ligament reconstruction (ACLR) with different graft types and with anterior cruciate ligament suture repair (ACLSR) can lead to differences in dynamic knee laxity and consequent differences in posttraumatic osteoarthritis (PTOA) development.

Purpose

To compare the incidence of PTOA between different graft types used for primary ACLR and between primary ACLR and ACLSR. It was hypothesized that the incidence of PTOA would vary between ACLR with different autografts and allografts and between ACLR and ACLSR.

Study Design

Systematic review; Level of evidence, 1.

Methods

A search of the literature was performed to identify all randomized controlled trials (RCTs) comparing radiographic evidence of PTOA after ACLR between different graft types-hamstring tendon (HT) autograft, bone-patellar tendon-bone (BPTB) autograft, quadriceps tendon autograft, and allograft-and between ACLR and ACLSR. The minimum follow-up was 2 years. Study quality was assessed using the modified Coleman Methodology Score. A meta-analysis was performed to determine whether there was a difference in the incidence of PTOA between the different graft types and between ACLR and ACLSR.

Results

Eleven randomized controlled trials were included in the meta-analysis-HT: 440 patients (mean follow-up, 9.7 years); BPTB: 307 patients (mean follow-up, 11.8 years); allograft: 246 patients (mean follow-up, 5 years); ACLSR, 22 patients (5 years). No study reporting the incidence after ACLR with quadriceps tendon was included. The study quality ranged from 70 to 88. The meta-analysis indicated no significant difference in the incidence of PTOA between graft types used for ACLR and between ACLR and ACLSR (risk ratios: HT vs BPTB, 1.05; HT vs allograft, 0.81; BPTB vs allograft, 0.82; HT vs ACLSR, not estimable [P > .05 for all]). The combined number of patients with PTOA in all studies per graft type showed that patients who underwent ACLR with a BPTB autograft had the highest percentage of PTOA (HT, 23.4%; BPTB, 29.6%; allograft, 8.1%; ACLSR, 0%). However, excluding studies with a follow-up <5 years resulted in similar outcomes for patients with an HT autograft and a BPTB autograft.

Conclusion

This meta-analysis reported no difference in the incidence of PTOA between graft types used for ACLR and between ACLR and ACLSR. More research is necessary to make a reliable conclusion about which technique is associated with the lowest incidence of PTOA after ACL surgery.

Not all patient-reported outcome measures are equivalent at two years compared to one year after anterior cruciate ligament reconstruction based on a retrospective analysis

OBJECTIVE

This article aims to assess for clinically important differences in patient-reported outcome measures (PROMs) at one and two years post anterior cruciate ligament reconstruction (ACLR).

METHODS

A retrospective comparison of prospectively collected PROMs for a single cohort who underwent a primary ACLR with or without associated meniscal surgery from 2016 to 2020 was assessed. Six externally validated PROMs were collected preoperatively and at standardized times postoperatively. Descriptive statistics and paired equivalence testing of PROMs at one and two years after surgery was completed using previously published or calculated minimal clinically important differences as upper and lower equivalence limits. A repeated measures analysis of PROMs that were not clinically equivalent at one and two years after surgery was completed to assess for a clinically significant difference. Subgroup analyses based on sex, age and associated meniscal injury were completed.

RESULTS

One-hundred and forty-five participants with a mean age of 28.7 years (standard deviation: 9.9 years) were included in the final analysis. All PROMs were clinically equivalent at two years compared to one year after ACLR except the quality of life and sport and recreation domains of the Knee Injury and Osteoarthritis Outcome Score (KOOS). The quality of life (mean difference (MD):12.3, P ​< ​0.01, effect size (η2): 0.65) and sport and recreation (MD: 8.78, P ​< ​0.01, η2: 0.50) domains of the KOOS were clinically different at two years compared to one year postoperatively. No major differences were found in the subgroup analyses compared to the entire included sample.

CONCLUSION

While most PROMs were equivalent at two years compared to one year after ACLR, the quality of life and sport and recreation domains of the KOOS, which reflect knee performance during higher demand activities, exhibited a clinically significant difference.

LEVEL OF EVIDENCE

IV.

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.

ChatGPT Provides Unsatisfactory Responses to Frequently Asked Questions Regarding Anterior Cruciate Ligament Reconstruction

PURPOSE

To determine whether the free online artificial intelligence platform ChatGPT could accurately, adequately, and appropriately answer questions regarding anterior cruciate ligament (ACL) reconstruction surgery.

METHODS

A list of 10 questions about ACL surgery was created based on a review of frequently asked questions that appeared on websites of various orthopaedic institutions. Each question was separately entered into ChatGPT (version 3.5), and responses were recorded, scored, and graded independently by 3 authors. The reading level of the ChatGPT response was calculated using the WordCalc software package, and readability was assessed using the Flesch-Kincaid grade level, Simple Measure of Gobbledygook index, Coleman-Liau index, Gunning fog index, and automated readability index.

RESULTS

Of the 10 frequently asked questions entered into ChatGPT, 6 were deemed as unsatisfactory and requiring substantial clarification; 1, as adequate and requiring moderate clarification; 1, as adequate and requiring minor clarification; and 2, as satisfactory and requiring minimal clarification. The mean DISCERN score was 41 (inter-rater reliability, 0.721), indicating the responses to the questions were average. According to the readability assessments, a full understanding of the ChatGPT responses required 13.4 years of education, which corresponds to the reading level of a college sophomore.

CONCLUSIONS

Most of the ChatGPT-generated responses were outdated and failed to provide an adequate foundation for patients' understanding regarding their injury and treatment options. The reading level required to understand the responses was too advanced for some patients, leading to potential misunderstanding and misinterpretation of information. ChatGPT lacks the ability to differentiate and prioritize information that is presented to patients.

CLINICAL RELEVANCE

Recognizing the shortcomings in artificial intelligence platforms may equip surgeons to better set expectations and provide support for patients considering and preparing for 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.

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.

Acute anterior cruciate ligament rupture: can repair become an alternative to reconstruction: a meta-analysis of randomized controlled trials and cohort studies

PURPOSE

To perform a meta-analysis to compare clinical outcomes of anterior cruciate ligament (ACL) repair and ACL reconstruction for acute ACL rupture.

METHOD

We searched Pubmed, Embase, the Cochrane Library, and Web of Science databases to seek relevant studies. Clinical outcomes included failure rate, hardware removal rate, anteroposterior (AP) knee laxity, and patient-reported outcomes. In addition, subgroup analysis was carried out according to repair techniques, rupture locations, and study designs. Funnel plots were used to detect publication bias. All statistical analysis was performed using STATA (version 14.2, StataCorp).

RESULTS

A total of 10 articles were included in this study, comprising 5 randomized controlled trials (RCTs) and 5 cohort studies, involving a total of 549 patients. We found no statistical differences between the ACL repair and ACL reconstruction in the following outcomes: failure rate, AP knee laxity, International Knee Documentation Committee (IKDC) score, Lysholm score, Knee Injury and Osteoarthritis Outcome (KOOS) Score, and Tegner score. However, the ACL repair group had a higher hardware removal rate. Except for AP knee laxity results on different repair techniques, there was no statistical difference in other subgroup analyses.

CONCLUSION

Compared with ACL reconstruction, ACL repair shows similar results in clinical outcomes, and it is promising to be an effective alternative treatment for acute ACL rupture. Larger samples and higher-quality studies are needed to support our results and further explore the advantages of ACL repair in other aspects.

LEVEL OF EVIDENCE

Level III.

Clinical Results of Primary Repair Versus Reconstruction of the Anterior Cruciate Ligament: A Systematic Review and Meta-analysis of Contemporary Trials

Background

Primary anterior cruciate ligament (ACL) repair has gained renewed interest in select centers for patients with proximal or midsubstance ACL tears. Therefore, it is important to reassess contemporary clinical outcomes of ACL repair to determine whether a clinical benefit exists over the gold standard of ACL reconstruction (ACLR).

Purpose

To (1) perform a meta-analysis of comparative trials to determine whether differences in clinical outcomes and adverse events exist between ACL repair versus ACLR and (2) synthesize the midterm outcomes of available trials.

Study Design

Systematic review; Level of evidence, 3.

Methods

The PubMed, OVID/Medline, and Cochrane databases were queried in August 2023 for prospective and retrospective clinical trials comparing ACL repair and ACLR. Data pertaining to tear location, surgical technique, adverse events, and clinical outcome measures were recorded. DerSimonian-Laird random-effects models were constructed to quantitatively evaluate the association between ACL repair/ACLR, adverse events, and clinical outcomes. A subanalysis of minimum 5-year outcomes was performed.

Results

Twelve studies (893 patients; 464 ACLR and 429 ACL repair) were included. Random-effects models demonstrated a higher relative risk (RR) of recurrent instability/clinical failure (RR = 1.64; 95% confidence interval [CI], 1.04-2.57; P = .032), revision ACLR (RR = 1.63; 95% CI, 1.03-2.59; P = .039), and hardware removal (RR = 4.94; 95% CI, 2.10-11.61; P = .0003) in patients who underwent primary ACL repair versus ACLR. The RR of reoperations and complications (knee-related) were not significantly different between groups. No significant differences were observed when comparing patient-reported outcome scores. In studies with minimum 5-year outcomes, no significant differences in adverse events or Lysholm scores were observed.

Conclusion

In contemporary comparative trials of ACL repair versus ACLR, the RR of clinical failure, revision surgery due to ACL rerupture, and hardware removal was greater for primary ACL repair compared with ACLR. There were no observed differences in patient-reported outcome scores, reoperations, or knee-related complications between approaches. In the limited literature reporting on minimum 5-year outcomes, significant differences in adverse events or the International Knee Documentation Committee score were not observed.

Outcomes of Primary Anterior Cruciate Ligament (ACL) Repair for Proximal Tears: A Systematic Review and Meta-Analysis

The purpose of this study is to compare failure rates among different techniques of primary anterior cruciate ligament (ACL) repair for the treatment of proximal ACL ruptures. Meta-analysis and systematic review were completed, and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Studies from Embase, Cochrane, and PubMed published between June 2011 and June 2022 reporting outcomes of primary ACL repair on proximal tears with a minimum two-year follow-up were included. Primary ACL repair was divided into dynamic, static, and non-augmented repair. The primary outcome was failure rates, and the secondary outcomes included patient-reported outcomes (PROs) and anterior tibial stability (ATT). Eighteen studies on primary ACL repair were included, with a total of 614 patients (ages ranging from 6 to 65, 60% male). Only two studies were level 1 randomized controlled clinical trials. The static repair had a failure rate of 33 out of 261 (12.6%), non-augmented was 17 out of 179 (9.4%), and dynamic repair was 31 out of 174 (17.8%); no statistically significant difference was found comparing the failure rates (p = 0.090). PROs using the International Knee Documentation Committee (IKDC) and Lysholm scores had weighted averages of 91.7 (95% confidence interval (CI): 89.6-93.8) and 94.7 (95% CI: 92.7-96.7), respectively. ATT had a weighted average of 1.668 mm (95% CI: 1.002-2.334). The primary findings of this paper include a 12.6% combined failure rate for primary proximal ACL repair with no significant difference in failure rate or PROs when accounting for the methodology of repair at a minimum two-year follow-up. It is important to note the lack of high-quality randomized controlled trials, the heterogeneity of included studies, and the lack of long-term data. Despite these limitations, the findings of the current analysis suggest that primary repair may be a useful treatment option for indicated candidates with proximal ACL ruptures. Further long-term and higher-quality comparative studies on ACL reconstruction are warranted.

Patients With More Than 6.5° of Knee Hyperextension are 14.6 Times More Likely to Have Anterior Cruciate Ligament Hamstring Graft Rupture and Worse Knee Stability and Functional Outcomes

PURPOSE

To create a cut-off point for hyperextension that best discriminates retear and to verify whether this cut-off point can predict retear regardless of other characteristics after primary anterior cruciate ligament (ACL) reconstruction with hamstrings autograft.

METHODS

A cohort of patients submitted to primary isolated ACL reconstruction with hamstrings autografts was retrospectively evaluated. Patients were stratified according to the degree of passive knee hyperextension measured in the normal contralateral knee. The following data were collected: patient age and sex, time from injury to surgery, knee hyperextension, KT-1000 and pivot-shift, associated meniscus injury, intra-articular graft size, follow-up time, graft failure, and postoperative Lysholm and subjective International Knee Documentation Committee scores.

RESULTS

Data from 457 patients were evaluated. Median age was 31 years. Thirty-two (7.0%) presented with retear. There was a significant difference in hyperextension between patients with and without retear (P < .001), with the cut-off point established by the receiver operating characteristic curve from 6.5°. Patients with greater hyperextension had a statistically greater frequency of women, longer injury time, greater intra-articular graft diameter, greater postoperative KT-1000, and greater frequency of retear, whereas the subjective International Knee Documentation Committee and Lysholm scores were statistically lower in patients with greater hyperextension. Only hyperextension showed a statistically significant association with re-rupture (P < .001). The odds of retear in patients with hyperextension greater than 6.5 was 14.65 times the odds of patients with hyperextension less than 6.5.

CONCLUSIONS

Patients with more than 6.5° of hyperextension are 14.6 times more likely to have a graft rupture than patients with lower hyperextension when submitted to ACL reconstruction with hamstring tendons. Also, they present worse knee stability by the KT-1000 test and worse functional outcomes. Therefore, patients with this degree of hyperextension should not have isolated reconstruction with hamstrings as their first choice.

LEVEL OF EVIDENCE

Level III, retrospective comparative prognostic trial.

Comparison of Clinical Outcomes Between Modern Augmented ACL Repair and Autograft ACL Reconstruction: A Systematic Review and Meta-analysis of Studies With Minimum 2-Year Follow-up

Background

Anterior cruciate ligament (ACL) reconstruction has been the gold standard for primary ACL rupture since the 1990s. In the past decade, ACL repair has received renewed attention and increased research.

Purpose

To compare the clinical outcomes of modern augmented ACL repair versus autograft reconstruction for ACL ruptures.

Study Design

Systematic review; Level of evidence, 3.

Methods

A search of the PubMed, EMBASE, Scopus, Web of Science, and the Cochrane Library databases was conducted for prospective or retrospective comparative studies published between January 1, 2010, and January 3, 2023, with a minimum 2-year follow-up. Two independent reviewers performed data extraction and methodological quality assessment. Sensitivity analysis was performed to maintain the stability of results.

Results

Nine studies were included (minimum follow-up period, 24-60 months). The total sample size was 833 patients (augmented repair group: 358 patients; autograft ACL reconstruction group: 475 patients). There were 4 randomized controlled trials (level 1), 1 prospective comparative study (level 2), 2 retrospective comparative studies (level 3), and 2 case-control studies (level 3). The augmented ACL repair group attained significantly higher Lysholm score (weighted mean difference [WMD] = 1.57; 95% confidence interval [CI], 0.14-3.01; P = .03) and hamstring strength (WMD = 36.69; 95% CI, 29.07-44.31; P < .01) but had higher rates of hardware removal (odds ratio [OR] = 6.30; 95% CI, 2.44-16.23; P = .0001), reoperation (OR = 1.87; 95% CI, 1.33-2.62; P = .0003), and failure (OR = 1.58; 95% CI, 1.03-2.43; P = .0003) compared with the autograft ACL reconstruction group. No significant differences were observed between the repair and reconstruction groups regarding postoperative International Knee Documentation Committee scores, Tegner scores, knee laxity, satisfaction, ACL revisions, complications, and reoperation rather than revision.

Conclusion

Augmented ACL repair was associated with higher rates of reoperation, hardware removal, and failure compared with autograft ACL reconstruction in studies with minimum 2-year follow-up data. However, augmented ACL repair had higher Lysholm scores and hamstring strength versus autograft ACL reconstruction.

Refixation of the anterior cruciate ligament: A biomechanical analysis of suture techniques in a porcine model

Purpose

Refixation of acute anterior cruciate ligament (ACL) tears represents an increasingly popular treatment option. Systematic evaluations of various suture technique parameters are still pending. We therefore aimed to evaluate the mechanical pull-out outcomes of various suture methods for optimization of ACL refixation.

Methods

Sixty fresh knees from mature domestic pigs were dissected and the femoral attachment of the ACL was peeled off. The 60 knees were divided in 10 groups and sutured as follows: (A) one suture (1, 2, 4 and 6 passes), (B) two sutures (2, 4 and 6 passes each; sutures knotted together as a loop) and (C) two sutures (2, 4 and 6 passes each, sutures knotted separately). The pull-out test was conducted using a validated electrodynamic testing machine. First occurrence of failure, maximum pull-out load and stiffness were measured. Suture failure was defined as pull-out of the ACL.

Results

Two-point fixation, using two sutures, with at least two passes, showed the most favourable biomechanical stability. The maximum pull-out load was significantly higher with two sutures (529.5 N) used compared to one (310.4 N), p < 0.001. No significant differences were found for maximum pull-out loads between two-point fixation versus one-point fixation but stiffness was significantly higher with two-point fixation (107.4 N/mm vs. 79.4 N/mm, p < 0.001). More passes resulted in higher maximum pull-out loads.

Conclusion

The results suggest using two independent sutures, refixed separately and at least two suture passes, is appropriate for ACL refixation. More suture passes provide additional strength but are technically challenging to achieve during surgery.

Level of Evidence

Level IV.

Primary anterior cruciate ligament repair: Current concepts

The renewed interest in ACL repair over the last two decades stems from advances in modern arthroscopic techniques and clinical studies that have provided evidence that the ACL can reliably heal, and patients can return to sport at a comparable rate to ACL reconstruction patients. The ability to maintain and utilize native ACL tissue, with proprioceptive capabilities, and the smaller drill tunnels needed to repair an ACL leads to an overall less invasive procedure and improved early rehabilitation. Additionally, repair avoids a variety of comorbidities associated with autograft harvest. This current concept review details modern techniques of ACL repair and their current studies, a review on the use of biologic enhancement in ACL repair, and other considerations to appropriately integrate ACL repair into the sports medicine orthopaedic surgeon's practice.

ACL reconstruction provides superior stability than ACL repair in patients with Schenck III and IV knee joint dislocations: first results of a 12 month follow-up study

PURPOSE

Acute knee dislocation is a rare but devastating multi-ligamentous knee injury with only limited evidence-based surgical technique recommendations. The aim of this study was a comparison of two different anterior cruciate ligament (ACL) restoration techniques as part of an early total surgical care concept: (1) repair of ACL with additional internal bracing (ACLIB) compared to; (2) ACL reconstruction with autograft (ACLR).

METHODS

Retrospective, clinical-study of patients with an acute type III or IV knee dislocation (according to Schenck classification), in which the ACL was treated with ACLIB or ACLR within 12 days. The PCL was sutured and internally braced in all cases. Medial and lateral complex injuries were repaired and additionally laterally augmented by an Arciero reconstruction. After a minimum 12 months follow-up different patient-reported outcome measurements (IKDC, Lysholm, VAS, Tegner Score) and instrumental stability assessment by Rolimeter -test and stress radiographs (Telos™) were analyzed. Groups were compared by t test with p < 0.05 considered significant.

RESULTS

In total, 20 patients (5 IIIM, 5 IIIL and 10 IV) were included in this study with an average follow-up of 13.7 ± 2.6 months. There were significant differences in instrumental stability testing (side-to-side difference (SSD) of anterior tibial translation: ACLIB 2.7 ± 1.5 mm vs. ACLR 1.3 ± 1.3; p = 0.0339) and stress radiography (SSD ACL: ACLIB 3.4 ± 2.2 mm vs. ACLR 0.4 ± 2.7; p = 0.0249) between groups. ACLIB group showed greater ROM in terms of flexion (SSD Flexion: ACLIB 7.8 ± 9.9° vs. ACLR 16 ± 7.0°; p = 0.0466; Total Flexion overall 125.5 ± 11.8°). No clinically relevant differences in patient-reported outcome scores (Lysholm Score: ACLIB 82 ± 16.4 vs. ACLR 85 ± 10.4; IKDC subjective score: ACLIB 70.4 ± 17 vs. ACLR 76.6 ± 8.3) were determined.

CONCLUSION

ACLR provides superior translational stability than ACLIB in terms of instrumental testing and stress radiography. Both techniques were equivalent with respect to PROMS and led to good and excellent clinical results.

LEVEL OF EVIDENCE

Retrospective cohort study, III.

Graft failure and revision rate after ACL repair with dynamic intraligamentary stabilization. One-year results of a prospective case series of 155 patients

PURPOSE

The aim of this study was to assess graft failure, revision rate, and functional outcomes after treatment of acute ACL rupture with dynamic intraligamentary stabilization (DIS) Ligamys device one year post surgery. Additionally, differences in functional outcome between patients with and without anteroposterior laxity were assessed. It was hypothesized that the failure rate of DIS was non-inferior to that of previously reported ACL reconstruction (10%).

METHODS

In this prospectively designed multicenter study, including patients with an acute ACL rupture, DIS was performed within 21 days after rupture. Primary outcome was failure of the graft at 1 year post surgery, defined as 1) re-rupture of the graft, 2) revision of DIS, or 3) a > 3 mm side-to-side difference in anterior tibial translation compared to the non-operated knee (∆ATT), measured by the KT1000 device. Additional analysis was performed using a 5 mm threshold. The subjective International Knee Documentation Committee Score (IKDC) and Numerical Rating Scales (NRS) for pain and confidence were used to evaluate functional outcome.

RESULTS

A total of 155 patients were included with a mean age at surgery of 27.8 years (SD 9.4). The mean interval from rupture to DIS was 16.4 days (SD 5.2). At a median follow-up of 13 months (IQR 12-18) the failure rate of the graft was 30.2% (95%CI:22.0-39.4); 11 patients (7%) required secondary reconstructive surgery and of the 105 patients who attended ATT measurement, 24 patients (23%) had an ∆ATT > 3 mm. Secondary analysis, based on a 5 mm threshold, revealed a failure rate of 22.4% (95%CI: 15.2; 31.1). A total of 39 patients (25%) reported at least one complication, comprising mainly arthrofibrosis, traumatic re-rupture and pain. In these patients, removal of the monoblock was performed in 21 cases (13.5%). At follow-up no significant differences in functional outcomes between patients with ∆ATT > 3 mm and stable ATT were observed.

CONCLUSION

This prospective multicenter study found a high failure rate at one year follow-up of 30% (7% revision surgery and 23% > 3 mm side-to-side difference in anterior tibial translation) in patients treated by primary repair of the ACL with DIS, and did therefore not demonstrate non-inferiority to ACL reconstruction. For patients who did not require secondary reconstructive surgery, this study found good functional outcomes, also in case of persistent anteroposterior knee laxity (∆ATT > 3 mm).

LEVEL OF EVIDENCE

Level IV.

Clinical outcomes in dynamic intraligamentary stabilization technique for anterior cruciate ligament tear: A meta-analysis

BACKGROUND

To compare the clinical outcome between dynamic intraligamentary stabilization (DIS) and anterior cruciate ligament (ACL) reconstruction in ACL tears.

METHODS

PubMed, the Cochrane Library, and Embase databases were searched to identify published articles on clinical studies comparing DIS versus ACL reconstruction. The results of the eligible studies were analyzed in terms of anteroposterior knee laxity translation (ΔATT) between the injured and contralateral knees, and subjective International Knee Documentation Committee (IKDC), Lysholm score, Tegner score, and ipsilateral ACL failure, implant removal, and ACL revision.

RESULTS

Five clinical studies including 429 patients with ACL tears met the inclusion criteria. DIS showed statistically comparable outcomes of ΔATT (P = .12), IKDC (P = .38), Tegner (P = .82), ACL failure (P = .50), ACL revision (P = .29) with ACL reconstruction. A significantly higher rate of implant removal (odds ratio for DIS vs ACL reconstruction, 7.73; 95% confidence interval [CI], 2.72-22.00; P = .0001) but statistically higher Lysholm score (mean difference between DIS and ACL reconstruction, 1.59; 95% CI, 0.24-2.93; P = .02) were found in DIS group.

CONCLUSION

Five clinical studies including 429 patients with ACL tears met the inclusion criteria. DIS showed statistically comparable outcomes of ΔATT (P = .12), IKDC (P = .38), Tegner (P = .82), ACL failure (P = .50), ACL revision (P = .29) with ACL reconstruction. A significantly higher rate of implant removal (odds ratio for DIS vs ACL reconstruction, 7.73; 95% CI, 2.72-22.00; P = .0001) but statistically higher Lysholm score (mean difference between DIS and ACL reconstruction, 1.59; 95% CI, 0.24-2.93; P = .02) were found in DIS group.