Traumatic graft rupture after primary and revision anterior cruciate ligament reconstruction: retrospective analysis of incidence and risk factors in 2915 cases

Return to Sport and Graft Failure Rates After Primary Anterior Cruciate Ligament Reconstruction With a Bone-Patellar Tendon-Bone Versus Hamstring Tendon Autograft: A Systematic Review and Meta-analysis

BACKGROUND

Anterior cruciate ligament (ACL) tears are frequent injuries in athletes that often require surgical reconstruction so that patients may return to their previous levels of performance. While existing data on patient-reported outcomes are similar between bone-patellar tendon-bone (BTB) and hamstring tendon (HT) autografts, the literature regarding return to sport (RTS), return to previous levels of sport activity, and graft failure rate remains limited.

PURPOSE

To compare rates of RTS, return to previous activity levels, and graft retears among athletes undergoing primary ACL reconstruction using a BTB versus HT autograft.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

The MEDLINE, Embase, and Cochrane Library databases were queried, and studies reporting on RTS after primary ACL reconstruction using a BTB or HT autograft were included. Exclusion criteria included revision reconstruction, ACL repair, quadriceps tendon autografts, allografts, graft augmentation, or double-bundle autografts. Rates of RTS, return to previous levels of activity, and retears were extracted and analyzed across included studies.

RESULTS

A total of 33 articles met inclusion criteria, with a patient cohort of 4810 athletes. The overall RTS rate for all athletes was 80.4% (95% CI, 75.3%-84.6%) at a mean follow-up of 35.7 months, with 54.6% (95% CI, 48.5%-60.6%) returning to preinjury levels of activity. No significant difference was found between BTB and HT autografts with respect to rates of RTS, return to preinjury activity levels, or reruptures. The overall RTS rate in patients after primary ACL reconstruction with a BTB autograft was 83.3% (95% CI, 77.0%-88.2%), with 56.1% (95% CI, 49.3%-62.7%) returning to preinjury levels of activity. Conversely, the overall RTS rate in patients after primary ACL reconstruction with an HT autograft was 77.9% (95% CI, 70.3%-84.0%), with 53.5% (95% CI, 42.8%-63.9%) returning to preinjury levels of activity. The overall graft rerupture rate for the entire patient cohort was 3.6% (95% CI, 2.5%-5.1%), for patients with BTB grafts was 3.2% (95% CI, 1.9%-5.3%), and for patients with HT grafts was 4.4% (95% CI, 2.8%-6.8%).

CONCLUSION

Primary ACL reconstruction using BTB autografts demonstrated similar rates of RTS, return to previous activity levels, and reruptures compared with reconstruction using HT autografts.

Graft Type and Diameter Are Predictors of Reinjury After Transphyseal Anterior Cruciate Ligament Reconstruction in Pediatric and Adolescent Patients

Purpose

To report the rate of anterior cruciate ligament (ACL) graft failure by physis status (open, closing, closed) and to analyze which factors were associated with higher risk of ACL graft failure.

Methods

Patients younger than 18 years who underwent transphyseal ACL reconstruction (ACLR) between 2000 and 2018 at a single institution were reviewed at minimum 2 years after ACLR. Patient records were reviewed for anthropometrics, surgical techniques, and ACL graft failure. Patients were subsequently stratified based on physis status (open, closing, closed) and analyzed.

Results

A total of 272 patients (mean age of 15.4 ± 1.3 years) were assessed. The transtibial technique was used in 63.6% of cases. A hamstring autograft was used exclusively in the open physis group. A patellar tendon autograft was used in 65.9% of patients with a closing physis and 80.9% of patients with a closed physis. The overall graft failure rate was 13.2%, with a contralateral ACL injury rate of 11.0%. Kaplan-Maier analysis by physis status showed different injury free from ACL reinjury (P < .001). An open physis was associated with increased risk of ACL reinjury (hazard ratio, 5.2; P < .001) when compared to a closed physis. A closing physis presented a higher hazard ratio but was not statistically significant (hazard ratio, 2.6; P = .08). Hamstring graft type (P = .03) and lower graft diameter (P = .04) were significantly related to higher ACL reinjury after adjusting for physis status.

Conclusions

Transphyseal ACLR is a safe procedure in pediatric patients. The rate of reinjury was 13.2%. This rate decreases with skeletal maturity, use of patellar tendon autograft, and a larger graft diameter.

Level of Evidence

Level III, retrospective cohort study.

No Clinical Advantage of Harvesting a Patellar Bone Block Compared With All Soft-Tissue Graft in Primary Quadriceps Tendon Anterior Cruciate Ligament Reconstruction

PURPOSE

To compare patient-reported outcomes measurements and subsequent surgical interventions in patients treated with anterior cruciate ligament reconstruction (ACLR) using either quadriceps tendon autograft with a patellar bone block (bQT) or soft tissue only (sQT).

METHODS

All ACLRs performed between January 2010 and March 2022 were prospectively followed for 24 months and retrospectively evaluated. All primary ACLRs with full 24 months of follow-up data, without any previous surgery or any additional ligamentous interventions, were matched for major ACL risk factors, including sex, age, Tegner activity level [TAL], pivoting sports, and concomitant injuries. Patient-reported outcomes measurements (Lysholm score, visual analog scale for pain, and TAL) and subsequent surgical interventions were registered after 6, 12, and 24 months postoperatively. Binary logistic regression was used to assess the influence of graft type, age, preinjury TAL, sex, pivoting sports, and concomitant interventions on the need to undergo subsequent surgery.

RESULTS

After matching, 246 patients were included in the final analysis. Both groups did not differ regarding any preoperative patient demographics or intraoperative details. At final follow-up, no significant differences in mean Lysholm score (sQT: 90.8 ± 10.6, bQT: 91.8 ± 10.6, P = .46), median TAL (sQT: 6 [1-10], bQT: 6 [1-10], P = .53), and visual analog scale for pain (sQT: 0.7 ± 1.1, bQT: 0.7 ± 1.2, P = .70) were reported between both groups. A total of 70.3% (sQT-A: 70.7%, bQT: 69.9%, P = .89) of patients returned to or exceeded their preinjury activity level. In terms of revision ACLR, there was no statistically significant difference between bQT (3.3%) and sQT (4.1%). Similarly, no difference was observed in contralateral ACLR (bQT: 7.3% sQT: 11.4%). Regression analysis indicated that none of the studied factors, including the use of a patellar bone block, influenced subsequent surgery, revision ACLR, or contralateral ACLR.

CONCLUSIONS

Harvesting an additional patellar bone block in quadriceps tendon ACLR does not seem to affect postoperative patient-reported outcomes, ACL revision, or contralateral ACL reconstruction rates.

LEVEL OF EVIDENCE

Level III, cohort study.

Ensemble Algorithm for Risk Prediction of Clinical Failure After Anterior Cruciate Ligament Reconstruction

Background

Patient-specific risk profiles of clinical failure after anterior cruciate ligament reconstruction (ACLR) are meaningful for preoperative surgical planning and postoperative rehabilitation guidance.

Purpose

To create an ensemble algorithm machine learning (ML) model and ML-based web-based tool that can predict the patient-specific risk of clinical failure after ACLR.

Study Design

Cohort study; Level of evidence, 3.

Methods

Included were 432 patients (mean age, 26.8 ± 8.4 years; 74.1% male) who underwent anatomic double-bundle ACLR with hamstring tendon autograft between January 2010 and February 2019. The primary outcome was the probability of clinical failure at a minimum 2-year follow-up. The authors included 24 independent variables for feature selection and model development. The data set was split randomly into training sets (75%) and test sets (25%). Models were built using 4 ML algorithms: extreme gradient boosting, random forest, light gradient boosting machine, and adaptive boosting. In addition, a weighted-average voting (WAV) ensemble model was constructed using the ensemble-voting technique to predict clinical failure after ACLR. Concordance (area under the receiver operating characteristic curve [AUC]), calibration, and decision curve analysis were used to evaluate predictive performances of the 5 models.

Results

Clinical failure occurred in 73 of the 432 patients (16.9%). The 8 most important predictors for clinical failure were follow-up period, high-grade preoperative knee laxity, time from injury to ACLR, participation in competitive sports, posterior tibial slope, graft diameter, age at surgery, and medial meniscus resection. The WAV ensemble algorithm achieved the best predictive performance based on concordance (AUC, 0.9139), calibration (calibration intercept, -0.1806; calibration slope, 1.2794; Brier score, 0.0888), and decision curve analysis (greatest net benefits) and was used to develop an web-based application to predict a patient's clinical failure risk of ACLR.

Conclusion

The WAV ensemble algorithm was able to accurately predict patient-specific risk of clinical failure after ACLR. Clinicians and patients can use the web-based application during preoperative consultation to understand individual prediction outcomes.

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.

Reduction in re-rupture rates following implementation of return-to-sport testing after anterior cruciate ligament reconstruction in 313 patients with a mean follow-up of 50 months

OBJECTIVES

The objective of this study was to assess the mid-term effectiveness of a return to sport (RTS) test in relation to preventing anterior cruciate ligament (ACL) re-rupture and contralateral ACL injury following ACL reconstruction (ACLR). Furthermore, this study aimed to assess the timing of passing a, RTS-test after surgery, and the effect age has on RTS outcomes.

METHODS

Patients undergoing ACLR between August 2014 and December 2018 took an RTS-test following rehabilitation. The RTS-test consisted of the Anterior Cruciate Ligament Return to Sport After Injury Scale, a single-leg hop, a single-leg triple hop, a single-leg triple cross-over hop, a box-drop vertical jump down, a single-leg 4-rep max-incline leg press, and a modified agility T test. RTS-passing criteria were ≥90% limb symmetry index in addition to defined takeoff and landing parameters. Mid-term review assessed sporting level, ACL re-injury, and contralateral ACL injury.

RESULTS

A total of 352 patients underwent RTS-testing, following ACLR with 313 (89%) contactable at follow-up, a mean of 50 months (standard deviation: 11.41, range: 28-76) after surgery. The re-rupture rate was 6.6% after passing the RTS-test and 10.3% following failure (p ​= ​0.24), representing a 36% reduction. Contralateral ACL injury rate after surgery was 6% and was 19% lower in those passing the RTS test. The mean age of patients passing their first RTS-test was significantly higher than that of those who failed (p ​= ​0.0027). Re-ruptures in those who passed the RTS test first time occurred late (>34 months), compared to those who failed first time, which all occurred early (<33 months) (p ​= ​0.0015). The mean age of re-rupture was significantly less than those who did not sustain a re-rupture (p ​= ​0.025).

CONCLUSION

Passing a RTS-test following ACLR reduces ACL re-rupture by 36.21% and contralateral ACL injury by 19.15% at mid-term follow-up. Younger patients are more likely to fail a RTS-test and are at higher risk of contralateral ACL rupture.

LEVEL III EVIDENCE

Difference of Knee Strength Recovery Between Revision and Primary ACL Reconstruction

Different grafting procedures are available to restore knee stability after revision anterior cruciate ligament (ACL) reconstruction. We compared knee strength recovery between ACL revision surgery and primary reconstruction. One hundred and ten patients with ACL revision surgery were matched with 110 patients with primary reconstruction based on the graft procedure. The isokinetic knee strength had been assessed for the first 9 months post-surgery. Knee laxity, function, and activity score were also evaluated. Limb symmetry index for knee extensor and flexor strength was not different at 4-, 6- and 9-months post-surgery between revision surgery and primary reconstruction. These results depended on ipsilateral or contralateral graft choice. Ipsilateral hamstring tendon (HT) and contralateral bone-patellar-tendon-bone (BPTB) graft procedures were similar for a revision of a BPTB graft failure. Contralateral HT procedure was better than ipsilateral BPTB procedure for a revision of a HT graft failure. The early recovery of isokinetic knee strength after ACL revision surgery regardless of the HT or BPTB procedures, was similar to the recovery after primary ACL reconstruction with the same graft technique. These results apparently depended on a temporary quadriceps arthrogenic muscle inhibition and on a persistent donor site morbidity, concerning the new and the previous grafts, respectively.

Evaluation of Failed ACL Reconstruction: An Updated Review

Failure rates among primary Anterior Cruciate Ligament Reconstruction (ACLR) range from 3.2% to 11.1%. Recently, there has been increased focus on surgical and anatomic considerations which predispose patients to failure, including excessive posterior tibial slope (PTS), unaddressed high-grade pivot shift, and improper tunnel placement. The purpose of this review was to provide a current summary and analysis of the literature regarding patient-related and technical factors surrounding revision ACLR, rehabilitation considerations, overall outcomes and return to sport (RTS) for patients who undergo revision ACLR. There is a convincingly higher re-tear and revision rate in patients who undergo ACLR with allograft than autograft, especially amongst the young, athletic population. Unrecognized Posterior Cruciate Ligament (PLC) injury is a common cause of ACLR failure and current literature suggests concurrent operative management of high-grade PLC injuries. Given the high rates of revision surgery in young active patients who return to pivoting sports, the authors recommend strong consideration of a combined ACLR + Anterolateral Ligament (ALL) or Lateral extra-articular tenodesis (LET) procedure in this population. Excessive PTS has been identified as an independent risk factor for ACL graft failure. Careful consideration of patient-specific factors such as age and activity level may influence the success of ACL reconstruction. Additional technical considerations including graft choice and fixation method, tunnel position, evaluation of concomitant posterolateral corner and high-grade pivot shift injuries, and the role of excessive posterior tibial slope may play a significant role in preventing failure.

Estimation of Diameter of Quadrupled Hamstring Graft for ACL Reconstruction using Pre-operative MRI Measurement as a Predictive Tool

Introduction

The diameter of the quadrupled Hamstring graft plays a significant role in the incidence of graft failures for ACL reconstruction. The ability to predict the graft size pre-operatively can prepare the surgeon for alternatives in the event of an inadequate graft diameter.

Materials and methods

We retrospectively measured the diameter of the Semitendinosus tendon (ST) on the MRI in all patients who underwent arthroscopic ACL reconstruction using quadrupled Semitendinosus as their graft. We also estimated any correlation between various anthropometric data with pre-operative MRI based Cross Sectional Area (CSA) of the Hamstring tendon and final graft diameter in the South Asian population. The patients were included from Jan 2018 - Dec 2020.

Results

The minimum CSA of ST to predict an eventual graft diameter of 7.5mm was 10.7mm2. The MRI based cross-sectional area measurement showed moderate correlation with the intra-operative graft diameter obtained. (r=0.62, p<0.001). The intra-class correlation coefficient between the radiologist and the surgeon was 0.82, 95% CI (0.57, 0.92) and a p-value <0.001.

Conclusion

Pre-operative MRI can be a useful tool to predict the graft diameter. This coupled with the anthropometric data of the patient can be used as an adjunct to estimate the probable graft diameter. Thus, the surgeon can be better prepared for the surgery and can seek alternate graft options if the graft size is deemed inadequate pre-operatively.

Quadriceps tendon autograft has similar clinical outcomes when compared to hamstring tendon and bone-patellar tendon-bone autografts for revision ACL reconstruction: a systematic review and meta-analysis

PURPOSE

Research regarding revision anterior cruciate ligament reconstruction (RACLR) with quadriceps tendon (QT) autografts is lacking. The purpose of this study was to perform a systematic review and meta-analysis of RACLR with QT and compare its patient outcomes to RACLR with hamstring tendon (HT) and bone-patellar tendon-bone (BTB) autografts.

METHODS

Adhering to PRISMA guidelines, a search for studies using QT in RACLR was performed within PubMed, Scopus, and CINAHL from database date of inception through December 26, 2022. Primary outcomes sought included: failure rate, Lysholm scores, International Knee Documentation Committee (IKDC) scores, IKDC grades, arthrometric knee side-to-side differences (STSD), pivot shift grade, donor site morbidity, return to sport, visual analog scale (VAS) pain scores.

RESULTS

Nine studies were included consisting of 606 RACLR: 349 QT, 169 HT, and 88 BTB. Overall failure rates were 7.6% QT, 13.3% HT, and 8.7% BTB. Mean weighted Lysholm scores were 85.8 ± 3.8 QT, 82.5 ± 3.8 HT and 86.6 ± 4.5 BTB. IKDC average scores were 82.3 ± 1.6 QT, 80.1 ± 1.7 HT, and 81.7 ± 5.5BTB. Combined rates of IKDC A/B grades were 88.4% and 80.0% for QT and HT, respectively. VAS average scores were 0.9 ± 1.1 QT, 1.4 ± 0.2 HT, and 0.7 ± 0.8 for BTB. Side-to-side difference was reported for QT and HT with average values of 1.7 ± 0.6 mm and 2.1 ± 0.5 mm, respectively. Grade 0 or 1 pivot shifts were reported in 96.2% of QT patients and 91.3% of HT. Donor site morbidity, only reported for QT and HT, was 14.6 ± 9.7% and 23.6 ± 14.1%, respectively. QT resulted in a mean Tegner score of 5.9 ± 1.5 versus HT 5.7 ± 1.5. Rate of return to pivoting sports was 38.0% QT, 48.6% HT, and 76.9% BTB. Across all outcomes, there was no significant difference when comparing QT to HT, QT to BTB, and QT compared to HT and BTB combined.

CONCLUSIONS

RACLR with QT yields satisfactory patient reported outcomes, satisfactory improvement in knee laxity, expected return to sport rates, and has an overall 7.6% failure rate. Outcomes are comparative to those of HT and BTB making it an acceptable graft choice for RACLR. Surgeons should consider using QT autograft for RACLR, especially when other autografts are unavailable.

LEVEL OF EVIDENCE

IV.

Return to Sports After ACL Augmentation With Anterolateral Reconstruction (ALR) Harvesting Gracilis Only Compared With ACL Reconstruction With ALR Harvesting Both Hamstring Tendons

BACKGROUND

Anterior cruciate ligament (ACL) repair (ACL-Rp) is known to be a valuable alternative to ACL reconstruction (ACL-Rc) in selected indications. The majority of the ACL-Rp techniques recommend the use of a synthetic brace. The use of the gracilis allows both a biological internal brace and anterolateral ligament reconstruction (ALR).

PURPOSE

The primary objective was to compare the early ability to return to sports between patients who underwent ACL-Rp using a gracilis autograft as an internal brace augmentation with ALR and patients who underwent the conventional ACL-Rc with ALR technique sacrificing both the gracilis and the semitendinosus. The secondary objective was to compare the failure rate, clinical scores, and return to sports at a minimum follow-up of 2 years.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A retrospective analysis was undertaken. A total of 49 patients who underwent ACL-Rp with ALR between December 2018 and May 2019 were propensity matched at a 1:1 ratio to those who underwent ACL-Rc with ALR during the same period. The decision to perform ACL-Rp with ALR was based on preoperative selection and intraoperative arthroscopic findings: proximal avulsion tear, partial ACL tear, low- to midlevel sports participation, and good tissue quality. The ability to return to sports was assessed using isokinetic tests and the Knee Santy Athletic Return to Sport test functional test at 6 months postoperatively. At the final follow-up, knee laxity parameters, return to sports, and clinical outcome (Lysholm score, Tegner Activity Scale score, International Knee Documentation Committee score, Knee injury and Osteoarthritis Outcome Score, and Anterior Cruciate Ligament-Return to Sport after Injury score) were recorded.

RESULTS

The ACL-Rp group had significantly less hamstring strength deficit when compared with their counterparts who underwent ACL-Rc (0.2% vs 10.2% in concentric, P < .001; 2.5% vs 14% in eccentric, P < .001). The mean Knee Santy Athletic Return to Sport test score was significantly higher in the ACL-Rc group (69.7% ± 16.6% [range, 19%-100%] vs 61% ± 16.8% [range, 19%-100%]; P = .001). In the ACL-Rp group, 61% (30/49) of the patients were authorized to return to pivot sports versus 41% (20/49) in the ACL-Rc group (P = .04). At a mean final follow-up of 31.4 ± 3.5 months, no significant differences were demonstrated between groups with respect to clinical scores and knee laxity parameters. There was a trend for a higher failure rate in the ACL-Rp group without any significance (ACL-Rp: 6.1% [3/49] vs ACL-Rc: 0%; P = .08).

CONCLUSION

At 6 months after operation, harvesting only the gracilis with this ACL-Rp and augmentation with ALR technique was linked to a better early ability to return to sports compared with the ACL-Rc with ALR technique harvesting both the gracilis and semitendinosus. This technique had a limited effect on early flexion strength and provided a satisfactory rerupture rate.

Synthetic grafts for anterior cruciate ligament reconstructive surgery

The quest for a good and durable substitute to anterior cruciate ligament (ACL) is driving scientists to explore new promising areas of research. Autologous and allogenic ligament reconstruction bring satisfactory results in managing ACL surgery although their use is associated with significant drawbacks. To overcome the limitations of biologic grafts, many artificial devices have been developed and implanted as a substitute to the native ACL over the past decades. Although many synthetic grafts used in the past have been withdrawn from the market due to early mechanical failures ultimately leading to synovitis and osteoarthritis, there is recently a resurgence of interest in the use of synthetic ligaments for ACL reconstruction. However, this new generation of artificial ligaments, despite promising initial results, have shown to produce serious side effects such as high rupture rates, insufficient tendon-bone healing and loosening. For these reasons, recent advancements in biomedical engineering are focusing on improving technical features of artificial ligaments combining mechanical properties to biocompatibility. Bioactive coatings and surface modification methods have been proposed to enhance synthetic ligament biocompatibility and promote osseointegration. The path to the development of a safe and effective artificial ligament is still full of challenges, however recent advancements are leading the way towards a tissue-engineered substitute to the native ACL.

Nonoperative Treatment for Traumatic Partial Graft Rupture After Anterior Cruciate Ligament Reconstruction: A 2-Year Follow-up Study

Background

There are no studies on the nonoperative treatment of traumatic partial anterior cruciate ligament (ACL) graft rupture.

Purpose/Hypothesis

The purpose of this study was to compare the clinical and radiological outcomes and failure rates between nonoperative treatment and revision ACL reconstruction for traumatic partial ACL graft rupture. We hypothesized that the outcomes and failure rates would be comparable and that nonoperative treatment of traumatic partial ACL graft rupture can produce satisfactory outcomes.

Study Design

Cohort study; Level of evidence, 3.

Methods

We retrospectively evaluated 2114 patients treated for isolated ACL rupture between January 2000 and June 2020. Patients with traumatic partial graft rupture after ACL reconstruction with minimum 2-year follow-up data were included. Patients who met all the following conditions were candidates for nonoperative treatment: (1) Lachman or pivot-shift grade 0 or 1 at 6 months after ACL reconstruction, (2) ACL graft with low to intermediate signal intensity on 1-year postoperative magnetic resonance imaging (MRI), and (3) MRI after reinjury showing definite evidence of trauma, some fibers remaining in continuity of the ACL graft, and no anterior tibial subluxation in the sagittal plane. The patients were divided into 2 groups according to treatment method: nonoperative treatment (group A) and revision ACL reconstruction (group B). Clinical scores, laxity test results, radiological outcomes, and graft failures were compared between the groups.

Results

In total, 47 patients had traumatic partial graft rupture (group A, n = 10; group B, n = 37). There were no significant differences between the 2 groups in terms of clinical scores, laxity tests, radiological outcomes, or graft failure.

Conclusion

The clinical and radiological outcomes of nonoperative treatment of traumatic partial graft rupture after ACL reconstruction were comparable with those of revision ACL reconstruction. Nonoperative treatment of traumatic partial ACL graft rupture can produce satisfactory outcomes in selected patients.

Double-bundle non-anatomic ACL revision reconstruction with allograft resulted in a low revision rate at 10 years

PURPOSE

This study aimed at reporting the long-term second revision rate and subjective clinical outcomes from a cohort of patients who underwent a double-bundle (DB) ACLR first revision with allograft at a single institution.

METHODS

The Institutional database was searched according to the following inclusion criteria: (1) patients that underwent DB-ACL first revision with Achilles tendon allograft, (2) surgery performed between January 2000 and December 2012, (3) age at revision ≥ 18 y/o. Patients' general information, history, surgical data, and personal contacts were extracted from charts. An online survey platform was implemented to collect responses via email. The survey questions included: date of surgeries, surgical data, date of graft failure and subsequent second ACL revision surgery, any other surgery of the index knee, contralateral ACLR, KOOS score, and Tegner scores.

RESULTS

Eighty-one patients were included in the survival analysis, mean age at revision 32 ± 9.2 y/o, 71 males, mean BMI 24.7 ± 2.7, mean time from ACL to revision 6.8 ± 5.4 years, mean follow-up time 10.7 ± 1.4 years. There were 12 (15%) second ACL revisions during the follow-up period, three females and nine males, at a mean of 4.5 ± 3 years after the index surgery. The overall survival rates were 85% from a second ACL revision and 68% from all reoperations of the index knee. Considering only the successful procedures (61 patients), at final follow-up, the mean values for the KOOS subscales were 84 ± 15.5 for Pain, 88.1 ± 13.6 for Symptoms, 93 ± 11.6 for ADL, 75 ± 24.5 for Sport, and 71 ± 19.6 for Qol. Twenty-nine (48%) patients performed sports activity at the same level as before ACLR failure.

CONCLUSIONS

Double-bundle ACL revision with fresh-frozen Achilles allograft yields satisfactory results at long-term follow-up, with an 85% survival rate from a second ACL revision at mean 10 years' follow-up and good patient-reported clinical scores.

LEVEL OF EVIDENCE

Level IV.

Return to Sports: A Risky Business? A Systematic Review with Meta-Analysis of Risk Factors for Graft Rupture Following ACL Reconstruction

BACKGROUND

The risk of sustaining a graft rupture after anterior cruciate ligament reconstruction (ACLR) is high. Contributing risk factors are, however, still not clearly identified.

OBJECTIVE

The aim of this systematic review was to identify and quantify risk factors for graft rupture after ACLR.

METHODS

A systematic review with meta-analysis (PROSPERO CRD42020140129) based on PRISMA guidelines was performed. MEDLINE, CINAHL and EMBASE were searched from inception to September 2021. Prospective and retrospective studies addressing risk factors for graft rupture after ACLR in males/females of all ages were considered. Meta-analyses using a random effect model (effect measure: odds ratio [OR] with 95% confidence interval [CI]) were performed. The GRADE tool was used to assess evidence quality.

RESULTS

Following full-text screening of 310 relevant papers, 117 were eventually included, incorporating up to 133,000 individuals in each meta-analysis. Higher Tegner activity level (≥ 7 vs < 7) at primary injury (OR 3.91, 95% CI 1.69-9.04), increased tibial slope (degrees) (OR 2.21, 95% CI 1.26-3.86), lower psychological readiness to return to sport (RTS) (OR 2.18, 95% CI 1.32-3.61), early surgery (< 12 vs ≥ 12 months) (OR 1.87, 95% CI 1.58-2.22), RTS (pre-injury level) (OR 1.87, 95% CI 1.21-2.91) and family history of ACL injury (OR 1.76, 95% CI 1.34-2.31) were all associated with increased odds of graft rupture. Higher age (OR 0.47, 95% CI 0.39-0.59), female sex (OR 0.88, 95% CI 0.79-0.98), fewer self-reported knee symptoms pre-reconstruction (OR 0.81, 95% CI 0.69-0.95) and concomitant cartilage injuries (OR 0.70, 95% CI 0.62-0.79) instead decreased the odds. Meta-analysis revealed no association between body mass index, smoking, joint laxity, RTS time, knee kinematics, muscle strength or hop performance and graft rupture.

CONCLUSION

Conspicuous risk factors for graft rupture were mainly sports and hereditary related. Few studies investigated function-related modifiable factors or included sports exposure data.

How limb dominance influences limb symmetry in ACL patients: effects on functional performance

BACKGROUND

Timing for return to sport (RTS) after anterior cruciate ligament (ACL) injury is paramount for the avoidance of a secondary injury. A common criterion in RTS decision-making is the limb symmetry index (LSI) which quantifies (a)symmetries between the affected and unaffected limb. Limb dominance is one of many factors that may contribute to the recovery of the LSI after ACL reconstruction. The purpose of this study was to examine how limb dominance affects the LSI of functional performance tasks nine months following ACL reconstruction (time of RTS).

METHODS

At time of return to sport, n = 100 patients (n = 48 injured the dominant limb, n = 52 injured the non-dominant limb, n = 34 female, n = 66 male) with ACL reconstruction surgery performed isokinetic strength measurements of the knee extensors and flexors, and drop jumps (DJ), single leg hop for distance (SHD) and 6 m timed hop (6MTH) testings.

RESULTS

The findings indicated that injury of the dominant leg led to significantly higher LSI values in maximal isokinetic knee extensor strength (p = 0.030). No significant differences were observed for maximal isokinetic knee flexor strength, DJ, SHD or 6MTH performance. Stratifying for sex revealed no significant differences. Simple regression analyses demonstrated that LSI in maximal knee extensor strength significantly predicted LSIs in DJ and SHD while explaining 14% and 18% of the respective variance.

CONCLUSIONS

Given that limb dominance affects the LSI of muscle strength suggests that a differentiated interpretation of the LSI with respect to limb dominance should be considered for a safe return to sport. Monoarticular knee extensor strength and multiarticular hop test performance are interrelated and thus can show asymmetries which are not maladaptive but established during years of habituation or training.

Etiology of Failed Anterior Cruciate Ligament Reconstruction: a Scoping Review

PURPOSE OF REVIEW

Recent literature was reviewed to identify and summarize the etiology of primary anterior cruciate ligament (ACL) reconstruction (ACLR) failure reported.

METHODS

The databases Embase, PubMed, and Medline were searched on March 10, 2022, for English-language, clinical studies that reported on the etiology of failure of primary ACLR. The studies were systematically screened in duplicate and data abstracted.

RECENT FINDINGS

Forty-three studies were identified that reported mode of failure in primary ACLR. Trauma (43 studies), technical error (11 studies), and biology (9 studies) remain the most reported etiologies of ACLR failure. A combination of causes was listed in three studies. No reported cause or "other" was listed in 22 studies. Many clinical studies fail to report etiology of ACLR failure. Level of detail provided regarding mode of failure varies widely. Trauma, technical error, and biological failure remain the leading etiologies of ACLR failure reported in recent literature. Technical error is likely underreported and a contributing factor in traumatic failures.

Good Short-Term Clinical Outcomes and Low Rates of Return to Sports after Repeat Revision ACL Reconstruction

Repeat revision anterior cruciate ligament reconstruction (ACL-R) is a rare, demanding procedure and, as such, has not been well studied. Most of the available literature shows improved functional outcomes compared with preoperative state but inferior results when compared with primary ACL-R, particularly regarding return to preinjury level of sports. The purpose of this study was to assess functional outcomes in patients who had undergone repeat revision ACL-R. The secondary aims were to register return to sports, associated meniscal and/or chondral lesions, and evaluate radiological anatomical parameters. Nine patients between 2011 and 2017 were evaluated, who had a minimum follow-up of 2 years. Median age at repeat ACL-R was 32 years (interquartile range [IQR], 30-34 years) and the median follow-up was 27 months (IQR, 24-39 months). Data collected prior to surgery and at last follow-up included patient demographics, operative findings, physical examination findings including pivot shift and KT-1000 arthrometer measurement; Lysholm and International Knee Documentation Committee (IKDC) subjective scores; and return to sports and level using the Tegner score. Knee Injury and Osteoarthritis Outcome Score (KOOS) subjective score and radiographic anatomical parameters were recorded at last follow-up. Mean IKDC and Lysholm score improvement was 25 points (confidence interval [CI] 12-37) and 25 points (CI 11-39), respectively (p < 0.001). The median postoperative KOOS score was pain: 93 (IQR, 64-96); symptoms: 94 (IQR, 83-97); activities of daily life: 96 (IQR, 90-100); sports: 75 (IQR, 50-90); and quality of life: 50 (IQR, 43-81). Postoperative median side-to-side KT-1000 arthrometer difference was 2 mm (IQR, 1-8 mm). The median radiographic posterior tibial slope was 10 degrees (IQR, 9-10). One patient was considered a failure at 16 months postoperative. Only 44% (four out of nine) patients were able to return to their sports. None of these patients had a cartilage injury, while three out of five patients who did not return to their sports had International Cartilage Regeneration & Joint Preservation Society grade III or IV cartilage injury. Patients should be counseled on the challenging outcomes of repeat revision ACL-R. This is Level IV, therapeutic case series.

The Use of Five-Strand Hamstring Autograft to Increase the Graft Size in Anterior Cruciate Ligament Reconstruction-A Prospective Cohort Study With Satisfactory Early Clinical Results

Objectives

To report on the outcomes of using 5-strand hamstring autograft to increase the graft size for anterior cruciate ligament (ACL) reconstruction and to determine whether the clinical results are comparable to using conventional 4-strand graft.

Methods

A prospective cohort study of patients with arthroscopic-assisted single-bundle ACL reconstruction using hamstring autograft from January 2019 to June 2021.The patients were prospectively recruited to undergo ACL reconstruction with either 5-strand hamstring graft (group A) or 4-strand hamstring graft (group B).

Results

In total, 45 patients were included into the study. The mean diameter of the final graft was 8.9 ± 0.6 cm in the 5-strand group and 7.5 ± 0.8 cm in the 4-strand group (P < .001). Four-strand graft diameter measurements were taken intraoperatively in the 5-strand group before preparation of the 5-strand graft. The mean graft diameter of the 4-strand grafts was similar in both groups: 7.3 ± 0.3 mm in group A and 7.5 ± 0.8 mm in group B (P = .72). There was no statistically significant difference between the 2 groups of patients in terms of the Lysholm score, Knee Injury and Osteoarthritis Outcome Score (KOOS) Symptoms, KOOS Pain, KOOS Activities of Daily Living, KOOS Sports and KOOS Quality of Life scores. There were no postoperative complications of wound infection in both groups of patients. There was one case of graft rupture (4.8%) in the 4-strand group, which required revision reconstruction with patellar tendon graft 9 months postoperatively. There was no case of graft rupture in the 5-strand group (P = .29).

Conclusions

The 5-strand hamstring graft technique provides a graft with significantly larger graft diameter than the quadrupled graft technique, with satisfactory short- to medium-term outcomes. The 5-strand graft is therefore a useful technique to increase the graft size when faced with the problem of small hamstring graft.

Level of Evidence

Level II, prospective cohort study.

Latin American formal consensus on the appropriate indications of extra-articular lateral procedures in primary anterior cruciate ligament reconstruction

OBJECTIVES

To create a practice guideline for the appropriate indications of an extra-articular procedure in primary anterior cruciate ligament reconstruction (ACLR).

METHODS

The formal consensus method described by the Haute Autorité de Santé was used. The Latin American Society of Arthroscopy, Articular Replacement, and Sports Injuries (SLARD) recruited three groups of experts on ACLR. Initially, the steering group, consisting of eight surgeons, performed a systematic review of the literature and elaborated on 192 scenarios for primary ACLR. The rating group, composed of 23 surgeons, rated each scenario in two rounds, with an in-between in-person meeting for discussion. Median scores and agreement levels were estimated to classify each scenario as inappropriate, uncertain or appropriate for adding anterolateral reconstruction. Finally, the lecture group, consisting of 10 surgeons, revised each stage of the method, results and interpretation.

RESULTS

Of the scenarios, 11.97% were rated as appropriate for adding an extra-articular lateral procedure, 7.81% as inappropriate and 80.21% as uncertain. The key recommendations for the addition of extra-articular lateral techniques were as follows: it is appropriate when the patient is under 25 years of age, has high-grade physical examination findings, practises a pivoting sport and has hyperlaxity; meanwhile, it is inappropriate when the patient has low-grade physical examination findings, has normal laxity and does not practise a pivoting sport.

CONCLUSIONS

The appropriate indications of extra-articular lateral procedures in primary ACLR were determined on the basis of the best available evidence and expert opinion following a formal consensus method.

LEVEL OF EVIDENCE

V.

Rates of Anterior Cruciate Ligament Rerupture in Adolescent Patients with and without Patella Alta

The objective of this study was to compare rates of anterior cruciate ligament (ACL) failure among adolescent patients to evaluate patella alta as a high-risk variable. Demographic and surgical data were retrospectively queried for patients ≤18 years of age with primary ACL reconstruction performed at a single academic center between 2011 and 2016 and minimum of 2-year clinical surveillance. Patellar height indices, including Caton-Deschamps index (CDI) and Insall-Salvati index (ISI), were retrospectively calculated from preoperative imaging to assess the presence of patella alta. Failure was defined as (1) ACL graft rerupture, (2) Lachman's grade 2 + , (3) presence of pivot shift, and (4) side-to-side difference of 3 mm on KT-1000 arthrometer. A total of 184 patients (84 females and 100 males) and 192 knees were identified, with an average age of 16.2 ± 1.8 years. Of these, 30 (15.63%) experienced ACL failure. Male sex was the only significant risk factor for rerupture (p = 0.026). The mean CDI was 1.06 ± 0.17 and mean ISI was 1.04 ± 0.15. Of the 49 knees that met criteria for patella alta on radiographic evaluation, rerupture occurred in seven (14.29%). Patella alta was not a significant risk factor for ACL failure among adolescent patients (p = 0.359 and 0.277). Only male sex was associated with increased rates of ACL failure. Age, graft selection technique, fixation construct, and presence of patella alta were not risk factors for reinjury. This study is a therapeutic case series and reflects level of evidence IV.

Correlation of Isokinetic Testing and ACL Failure With the Short Graft Tape Suspension Technique at Six Months

Purpose

The objective of this study was to correlate the data of the 6-month postoperative isokinetic muscle evaluation before resuming sports activities with the occurrence of ACL reconstruction rerupture after semitendinosus short graft.

Methods

From 2015 to 2018, all patients who were operated for an ACL reconstruction with a short semitendinosus autograft (TLS System) and who performed isokinetic tests on dynamometer at their 6th postoperative month were included in this study. The follow-up was prospective with the measurement of epidemiological, radiographic, and isokinetic parameters at 6 months of the ACL reconstruction. The cohort was divided into 2 groups: one group without an ACL reconstruction rerupture (Group 1) and the second group with a rerupture (Group 2).

Results

One hundred and four patients were analyzed with an average follow-up of 42.3 months (Minimum: 24; Maximum: 63.5), of which 11 patients (10.6%) had an ACL reconstruction rerupture. Group 1 consisted of 93 patients with an average age of 26.5 ± 9.0 years old who did not have an ACL reconstruction rerupture with an average follow-up of 41.6 ± 12.1 months. Group 2 consisted of 11 patients with an average age of 22.7 ± 6.1 years old, who had an ACL reconstruction rerupture with an average follow-up of 44.8 ± 11.3 months. Concerning extension force recovery, the ratio between operated and healthy knee was 81.8% ± 32.0 for Group 1, and 53.4% ± 20.6 for Group 2 (P = .035). A statistically significant difference was also found (P = .0017) during 60°/s flexion isokinetic test between the two groups.

Conclusions

This study revealed a significant link between muscle weakness in flexion and extension during 60°/s isokinetic test at 6 months of ACL reconstruction and semitendinosus autograft rerupture. Patients with an ACL reconstruction retear had inferior muscle dynamometric recovery results at 6 months before resuming sports activities.

Level of Evidence

Level III, prognostic, retrospective cohort study.

State of the mineralized tissue comprising the femoral ACL enthesis in young women with an ACL failure

Despite poor graft integration among some patients that undergo an anterior cruciate ligament (ACL) reconstruction, there has been little consideration of the bone quality into which the ACL femoral tunnel is drilled and the graft is placed. Bone mineral density of the knee decreases following ACL injury. However, trabecular and cortical architecture differences between injured and non-injured femoral ACL entheses have not been reported. We hypothesize that injured femoral ACL entheses will show significantly less cortical and trabecular mass compared with non-injured controls. Femoral ACL enthesis explants from 54 female patients (13-25 years) were collected during ACL reconstructive surgery. Control explants (n = 12) were collected from seven donors (18-36 years). Injured (I) femoral explants differed from those of non-injured (NI) controls with significantly less (p ≤ 0.001) cortical volumetric bone mineral density (vBMD) (NI: 736.1-867.6 mg/cm3 ; I: 451.2-891.9 mg/cm3 ), relative bone volume (BV/TV) (NI: 0.674-0.867; I: 0.401-0.792) and porosity (Ct.Po) (NI: 0.133-0.326; I: 0.209-0.600). Injured explants showed significantly less trabecular vBMD (p = 0.013) but not trabecular BV/TV (p = 0.314), thickness (p = 0.412), or separation (p = 0.828). We found significantly less cortical bone within injured femoral entheses compared to NI controls. Lower cortical and trabecular bone mass within patient femoral ACL entheses may help explain poor ACL graft osseointegration outcomes in the young and may be a contributor to the osteolytic phenomenon that often occurs within the graft tunnel following ACL reconstruction.

Minimizing the risk of graft failure after anterior cruciate ligament reconstruction in athletes. A narrative review of the current evidence

Anterior cruciate ligament (ACL) tear is one of the most common sport-related injuries and the request for ACL reconstructions is increasing nowadays. Unfortunately, ACL graft failures are reported in up to 34.2% in athletes, representing a traumatic and career-threatening event. It can be convenient to understand the various risk factors for ACL failure, in order to properly inform the patients about the expected outcomes and to minimize the chance of poor results. In literature, a multitude of studies have been performed on the failure risks after ACL reconstruction, but the huge amount of data may generate much confusion.The aim of this review is to resume the data collected from literature on the risk of graft failure after ACL reconstruction in athletes, focusing on the following three key points: individuate the predisposing factors to ACL reconstruction failure, analyze surgical aspects which may have significant impact on outcomes, highlight the current criteria regarding safe return to sport after ACL reconstruction.

Disparities in ACL Reconstruction: the Influence of Gender and Race on Incidence, Treatment, and Outcomes

PURPOSE OF REVIEW

Anterior cruciate ligament (ACL) rupture is a common injury that has important clinical and economic implications. We aimed to review the literature to identify gender, racial and ethnic disparities in incidence, treatment, and outcomes of ACL injury.

RECENT FINDINGS

Females are at increased risk for ACL injury compared to males. Intrinsic differences such as increased quadriceps angle and increased posterior tibial slope may be contributing factors. Despite lower rates of injury, males undergo ACL reconstruction (ACLR) more frequently. There is conflicting evidence regarding gender differences in graft failure and ACL revision rates, but males demonstrate higher return to sport (RTS) rates. Females report worse functional outcome scores and have worse biomechanical metrics following ACLR. Direct evidence of racial and ethnic disparities is limited, but present. White athletes have greater risk of ACL injury compared to Black athletes. Non-White and Spanish-speaking patients are less likely to undergo ACLR after ACL tear. Black and Hispanic youth have greater surgical delay to ACLR, increased risk for loss to clinical follow-up, and less physical therapy sessions, thereby leading to greater deficits in knee extensor strength during rehabilitation. Hispanic and Black patients also have greater risk for hospital admission after ACLR, though this disparity is improving. Females have higher rates of ACL injury with inconclusive evidence on anatomic predisposition and ACL failure rate differences between genders. Recent literature has suggested inferior RTS and functional outcomes following ACLR in females. Though there is limited and mixed data on incidence and outcome differences between races and ethnic groups, recent studies suggest there may be disparities in those who undergo ACLR and time to treatment.

Good Validity and High Internal Consistency of the Forgotten Joint Score-12 in Patients After Medial Opening Wedge High Tibial Osteotomy

BACKGROUND

The Forgotten Joint Score-12 (FJS-12) was originally developed to assess awareness of an artificial joint. Medial opening wedge high tibial osteotomy (MOWHTO), an alternative surgical method of knee replacement, is a joint-preservation surgery; therefore, joint awareness should be used to evaluate its clinical results. However, FJS-12 has not been validated as a tool to evaluate the postoperative results of MOWHTO. This study aimed to validate FJS-12 in MOWHTO.

METHODS

Patients with bilateral knee surgery, previous knee surgery, flexion contracture >15°, varus alignment >20°, and patients without plate removal surgery were excluded. Finally, 71 knees of 71 patients were analyzed, with a mean follow-up of 34.5 months. The FJS-12 score and Knee Injury and Osteoarthritis Outcome Score (KOOS) were obtained, and the floor and ceiling effect of each score was investigated. Cronbach's α was calculated to determine the internal consistency of FJS-12. Spearman's correlation coefficients between FJS-12 and KOOS were calculated to assess convergent validity.

RESULTS

There were ceiling effects in 3 KOOS subscales (symptoms [25.4%], pain [15.5%], and activities of daily living [25.4%]) but not in FJS-12 (8.5%). No floor effect was noted in any patient-reported outcome measures. The total Cronbach's α was 0.9457 in FJS-12. FJS-12 showed moderate-to-strong positive correlations with all KOOS subscales (r = 0.64-0.72).

CONCLUSION

FJS-12 showed a lower ceiling effect than KOOS and high internal consistency and convergent validity in patients following MOWHTO. With its low ceiling effect, FJS-12 was found to be useful for evaluating patients following MOWHTO.

The role of magnetic resonance imaging in evaluating postoperative ACL reconstruction healing and graft mechanical properties: a new criterion for return to play?

Background: Disruption of the anterior cruciate ligament (ACL) is a common injury. In active patients, it is routinely treated with ACL reconstruction surgery. Following reconstruction, one of the critical decisions that must be made is the optimal timing of return to sport. While many biomechanical, biological, and functional criteria have been proposed to determine return to play, these methods are limited at best.Reasoning: As criteria for return to play are multifactorial, there is a growing need for noninvasive technologies, such as magnetic resonance imaging (MRI), to objectively track graft healing, to better assess the graft itself. Measuring the changes in the strength of the healing ligament has been shown to be a reliable means of objectively documenting graft healing in preclinical studies. While the initial studies of MR-based modeling of ACL graft healing are promising, this technology is still in its infancy and requires optimization.Purpose: The goals of this review are: 1) to outline the shortcomings of current return to play criteria, 2) to highlight the ability of MRI to determine the status of ACL graft healing, and 3) to discuss the future of imaging technology to determine return to play and its potential role in the clinical evaluation of patientsConclusion: There continues to be a wide variabiltiy regarding adequate return to play criteria, most of which are subjective in nature.

Effect of Leg Dominance on Medium- to Long-Term Functional Outcomes, Quality of Life, and Revision Rates After Isolated ACL Reconstruction

Background:

The effect of leg dominance on short-term functional outcomes and return to sports after arthroscopic anterior cruciate ligament reconstruction (ACLR) has been evaluated. However, postoperative medium- to long-term recovery and revision rates are not well known.

Purpose:

To investigate whether leg dominance affects medium- to long-term clinical and functional scores and revision rates after ACLR.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Included in this study were 235 patients (205 male and 30 female) who underwent isolated arthroscopic ACLR. Patients were divided according to the leg dominance status of their injured limb into 2 groups: dominant leg injured (120 patients) and nondominant leg injured (115 patients). Preoperative and postoperative functional outcomes and health-related quality of life (HRQoL) were evaluated using the visual analog scale for pain, Tegner activity scale, Lysholm knee score, International Knee Documentation Committee (IKDC) subjective knee evaluation form, 36-Item Short Form Health Survey (SF-36), and overall patient satisfaction. Moreover, the revision rates of the 2 groups were compared according to leg dominance, patient characteristics, and operative features.

Results:

The mean follow-up period was 8.0 ± 2.3 years (range, 5-13 years). A significant preoperative to postoperative improvement in range of motion and functional scores was noticed in both groups (P < .001 for all). However, the improvement was significantly higher in the dominant leg group for the Tegner (P = .001), Lysholm (P = .006), and IKDC (P < .001) scores as well as for the SF-36 domain scores for general health (P = .009), social role (P = .048), and emotional role (P = .032). Also, patient satisfaction was significantly higher in the dominant leg group (P = .007). The dominant leg group was associated with a lower revision rate compared with the nondominant leg group (5.8% vs 15.7%, respectively; P = .015).

Conclusion:

High recovery rates were seen after arthroscopic ACLR, regardless of leg dominance. However, leg dominance had a significant effect on postoperative medium- to long-term functional outcomes, HRQoL, and revision rates.

A Systematic Review of Risk Factors for Anterior Cruciate Ligament Reconstruction Failure

Although most studies have introduced risk factors related to anterior cruciate ligament reconstruction failure, studies on combinations of high-risk factors are rare. To provide a systematic review of the risk factors of anterior cruciate ligament reconstruction failure to guide surgeons through the decision-making process, an extensive literature search was performed of the Medline, Embase and Cochrane Library databases. Studies published between January 1, 2009, and September 19, 2019, regarding the existing evidence for risk factors of anterior cruciate ligament reconstruction failure or graft failure were included in this review. Study quality was evaluated with the quality index. Ultimately, 66 articles met our criteria. There were 46 cases classified as technical factors, 21 cases as patient-related risk factors, and 14 cases as status of the knee joint. Quality assessment scores ranged from 14 to 24. This systematic review provides a comprehensive summary of the risk factors for anterior cruciate ligament reconstruction failure, including technical factors, patient-related factors, and the factors associated with the status of the knee joint. Emphasis should be placed on avoiding these high-risk combinations or correcting modifiable risk factors during preoperative planning to reduce the rate of graft rupture and anterior cruciate ligament reconstruction failure.

Low Rate of Return to Preinjury Tegner Activity Level Among Recreational Athletes: Results at 1 Year After Primary ACL Reconstruction

Background

There is limited information about the functional recovery and rate of return to preinjury levels of sports among recreational athletes after anterior cruciate ligament reconstruction (ACLR).

Purpose

To investigate the recovery of quadriceps or hamstring strength, assess functional performance, and determine the rate of return to preinjury sports levels among recreational athletes at 1 year after ACLR.

Study Design

Cohort study; Level of evidence, 3.

Methods

A total of 91 recreational-level athletes who underwent anatomic single-bundle ACLR were enrolled. We evaluated the limb symmetry index (LSI) of the quadriceps and hamstring peak torque strength at 60°, in addition to hop test performance (single-leg, triple, crossover, and 6-m timed), patient-reported outcomes, and pre- versus postoperative Tegner activity levels. Outcomes were compared between younger (age <25 years) and older patients (age ≥25 years).

Results

There were 48 patients in the younger group and 43 patients in the older group. At 1-year follow-up, the overall LSIs for quadriceps strength and hamstring strength were 77% and 86%, respectively, and the LSIs of the hop tests were 79% for single-leg, 81% for triple, 84% for crossover, and 85% for 6-m timed hop. Overall, only 24% patients returned to their preinjury Tegner level, and only 8% of patients met the criteria for return to pivoting, cutting, and jumping sports. At 1-year follow-up, the younger group showed significantly more quadriceps strength than the older group (85% vs 64%; P = .0001), better single, triple, crossover, and 6-m timed hop test results (85% vs 69%, P = .003; 84% vs 75%, P = .046; 91% vs. 74%, P < .001; and 91% vs 76%, P = .003, respectively), higher Lysholm score (87 vs 74; P < 0.001) and International Knee Document Committee score (82 vs 66; P < .001), and a higher rate of return to preinjury Tegner level (35% vs 12%; P = .009).

Conclusion

Only 24% of patients returned to the preinjury Tegner level at 1 year after ACLR (35% younger group vs 12% older group; P = .009). This information might be helpful in setting realistic expectations for recreational athletes after surgery.

Anterior Cruciate Ligament Reconstruction Using Bone-Patellar Tendon-Bone Autograft With Suture Tape Augmentation

The anterior cruciate ligament (ACL) is the most commonly injured ligament in the knee, with injury usually occurring as a result of multidirectional sports. The incidence of ACL injury has continued to increase, with most patients opting for surgery to improve stability as well as permit a return to sport. Traditional methods of ACL reconstruction can achieve this but are not without their problems, including graft rupture, residual laxity, and donor-site morbidity. There is therefore a requirement for further research into newer, innovative surgical techniques to help improve complication rates. This article describes, with video illustration, ACL reconstruction using a reduced-size bone-patellar tendon-bone autograft with suture tape augmentation. The augmentation acts as a stabilizer during the early stages of graft incorporation while resisting against reinjury during an accelerated recovery. The ability to use a reduced-size graft decreases the donor-site burden, and retention of residual native ACL tissue, when possible, may help with proprioception.

Insufficient evidence to support peroneus longus tendon over other autografts for primary anterior cruciate ligament reconstruction: a systematic review

IMPORTANCE

Graft choice for anterior cruciate ligament reconstruction (ACLR) remains a subject of interest among orthopaedic surgeons because no ideal graft has yet been found. Peroneus longus tendon (PLT) has emerged as an alternative autograft for reconstruction in kneeling populations and in simultaneous anterior cruciate ligament (ACL) and medial collateral ligament (MCL) injuries.

OBJECTIVE

To evaluate the current evidence on the outcome of primary ACLR with PLT autograft in adults and donor ankle morbidity, in addition to determining the average PLT graft dimensions from published studies.

EVIDENCE REVIEW

Two independent reviewers searched PubMed, CENTRAL, EMBASE, Scopus and Virtual Health Library databases using the terms "anterior cruciate ligament," "peroneus longus" and "fibularis longus" alone and in combination with Boolean operators AND/OR. Studies evaluating clinical and stability outcomes, graft-donor ankle morbidity and graft dimensions of PLT in ACLR were included. Methodological quality was assessed using the Modified Coleman Methodology Score (mCMS). A narrative analysis is presented using frequency-weighted means wherever feasible. Publication bias was assessed using the ROBIS tool.

FINDINGS

Twelve articles with intermediate-level methodological quality were included. Eight studies assessing the clinical and stability outcomes of reconstruction with PLT showed satisfactory outcomes, similar to those of hamstring tendons (HT). No studies assessed anterior knee pain as an outcome. Six studies evaluated the graft-donor ankle morbidity using general functional foot and ankle scores and non-validated tools, showing favourable outcomes. Nine studies assessed PLT graft diameter, revealing grafts consistently larger than 7 mm among the different preparation techniques, which is comparable with reports of HT grafts.

CONCLUSIONS AND RELEVANCE

The clinical and stability outcomes of ACLR with different PLT autograft preparation techniques are comparable with those of HT during short-term follow-up; however, there is insufficient evidence to support its use in the populations that motivated its implementation. Thus, stronger evidence obtained with the use of validated tools reporting negligible donor-graft ankle morbidity after PLT harvesting is required prior to recommending its routine use, despite the consistency of its dimensions.

LEVEL OF EVIDENCE

Level III.

Return to Sport After ACL Reconstruction With a BTB Versus Hamstring Tendon Autograft: A Systematic Review and Meta-analysis

Background

Anterior cruciate ligament (ACL) tears are debilitating injuries frequently suffered by athletes. ACL reconstruction is indicated to restore knee stability and allow patients to return to prior levels of athletic performance. While existing literature suggests that patient-reported outcomes are similar between bone-patellar tendon-bone (BTB) and hamstring tendon (HT) autografts, there is less information comparing return-to-sport (RTS) rates between the 2 graft types.

Purpose

To compare RTS rates among athletes undergoing primary ACL reconstruction using a BTB versus HT autograft.

Study Design

Systematic review; Level of evidence, 4.

Methods

The MEDLINE, Embase, and Cochrane Library databases were searched, and studies that reported on RTS after primary ACL reconstruction using a BTB or HT autograft were included. Studies that utilized ACL repair techniques, quadriceps tendon autografts, graft augmentation, double-bundle autografts, allografts, or revision ACL reconstruction were excluded. RTS information was extracted and analyzed from all included studies.

Results

Included in the review were 20 articles investigating a total of 2348 athletes. The overall RTS rate in our cohort was 73.2%, with 48.9% returning to preinjury levels of performance and a rerupture rate of 2.4%. The overall RTS rate in patients after primary ACL reconstruction with a BTB autograft was 81.0%, with 50.0% of athletes returning to preinjury levels of performance and a rerupture rate of 2.2%. Patients after primary ACL reconstruction with an HT autograft had an overall RTS rate of 70.6%, with 48.5% of athletes returning to preinjury levels of performance and a rerupture rate of 2.5%.

Conclusion

ACL reconstruction using BTB autografts demonstrated higher overall RTS rates when compared with HT autografts. However, BTB and HT autografts had similar rates of return to preinjury levels of performance and rerupture rates. Less than half of the athletes were able to return to preinjury sport levels after ACL reconstruction with either an HT or BTB autograft.

Trauma and femoral tunnel position are the most common failure modes of anterior cruciate ligament reconstruction: a systematic review

PURPOSE

To improve outcomes of anterior cruciate ligament reconstruction (ACLR), it is important to understand the reasons for failure of this procedure. This systematic review was performed to identify current failure modes of ACLR.

METHODS

A systematic search was performed using PubMed, EMBASE, Cochrane, and annual registries for ACLR failures. Studies were included when failure modes were reported (I) of ≥ 10 patients and (II) at a minimum of two-year follow-up. Modes of failure were also compared between different graft types and in femoral tunnel positions.

RESULTS

This review included 24 cohort studies and 4 registry-based studies (1 level I, 1 level II, 10 level III, and 16 level IV studies). Overall, a total of 3657 failures were identified. The most common single failure mode of ACLR was new trauma (38%), followed by technical errors (22%), combined causes (i.e. multiple failure mechanisms; 19%), and biological failures (i.e. failure due to infection or laxity without traumatic or technical considerations; 8%). Technical causes also played a contributing role in 17% of all failures. Femoral tunnel malposition was the most common cause of technical failure (63%). When specifically looking at the bone-patellar tendon-bone (BPTB) or hamstring (HT) autografts, trauma was the most common failure mode in both, whereas biological failure was more pronounced in the HT group (4% vs. 22%, respectively). Technical errors were more common following transtibial as compared to anteromedial portal techniques (49% vs. 26%).

CONCLUSION

Trauma is the single leading cause of ACLR failure, followed by technical errors, and combined causes. Technical errors seemed to play a major or contributing role in large part of reported failures, with femoral tunnel malposition being the leading cause of failure. Trauma was also the most common failure mode in both BPTB and HT grafts. Technical errors were a more common failure mode following transtibial than anteromedial portal technique.

LEVEL OF EVIDENCE

IV.

Influence of hamstring autograft diameter on graft failure rate in Chinese population after anterior cruciate ligament reconstruction

Background

There has been limited literature regarding the influence of hamstring autograft diameter on the outcome of anterior cruciate ligament (ACL) reconstruction in Asian population. This study was undertaken to investigate the failure rate after ACL reconstruction among Chinese patients treated with hamstring tendon autografts of different diameters. Our hypothesis was that an increase in hamstring tendon autograft diameter would reduce the risk of graft failure.

Methods

A retrospective review of 394 consecutive patients who underwent ACL reconstruction using quadrupled semitendinous and gracillis autografts from 2009 to 2018 at our centre was performed. Logistic regression analysis was used to determine the relationship between graft failure rate and predictor variables, including hamstring graft diameter, gender and age.

Results

Hamstring graft diameter of 8.0 mm or more was found to be associated with significant reduction of risk in graft failure rate (P = 0.001, Relative Risk 0.19). No significant association was found between graft failure rate and gender or age.

Conclusion

Hamstring graft diameter 8.0 mm or greater is associated with decreased graft failure rate and revision rate in our local Chinese population.

Anterior Cruciate Ligament Reconstructions With Quadriceps Tendon Autograft Result in Lower Graft Rupture Rates but Similar Patient-Reported Outcomes as Compared With Hamstring Tendon Autograft: A Comparison of 875 Patients

BACKGROUND

Graft rupture is a devastating outcome after anterior cruciate ligament (ACL) reconstruction (ACLR). Little is known about graft rupture rates as well as clinical and functional outcomes after ACLR with quadriceps tendon (QT) autografts.

PURPOSE

To compare QT with hamstring tendon (HT) autografts in terms of the rates of graft and contralateral ACL rupture as well as patient-reported outcome measures.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

All primary ACLRs performed between 2010 and 2016 were followed prospectively for 24 months through the recording of graft ruptures and contralateral ACL injuries as well as patient-administered questionnaires.

RESULTS

A total of 875 patients were included in the study. Three factors-graft type, age group, and activity level-had a significant value in predicting the need for revision surgery. The odds of revision surgery were 5.5 times greater in children younger than 15 years than in adults older than 45 years, 3.6 times greater in patients with high activity levels than low activity levels, and 2.7 times greater in patients receiving an HT autograft as compared with a QT autograft. A significantly higher rate of ipsilateral graft ruptures versus contralateral ACL injuries was observed in the HT group (4.9% vs 2.3%; odds ratio, 2.1; P = .01) but not in the QT group (2.8% vs 2.3%). The difference in the ratios of graft and contralateral ACL ruptures was even more pronounced in highly active patients treated with HT autografts (11.1% vs 4.2%; odds ratio, 2.6; P = .01) as compared with QT autografts (5.0% vs 2.8%; P = .48). Two-year measures of Lysholm scores (mean ± SD: QT, 86.0 ± 22.3; HT, 89.4 ± 16.4) and Tegner activity scores (QT, 6.1 ± 2.0; HT, 5.7 ± 1.9) as well as visual analog scale pain (QT, 0.8 ± 1.3; HT, 0.7 ± 1.1) did not differ between grafts.

CONCLUSION

Graft choice does not influence clinical and functional outcomes 2 years after ACLR. However, 3 factors-graft type, age group, and activity level-have a significant value in predicting the need for revision surgery. Patients treated with HT autografts have a significantly higher, activity-dependent risk of revision surgery and experience more ipsilateral graft ruptures than subsequent contralateral ACL injuries when compared with patients treated with QT autografts. Young age and high activity level are significant predictors for ACL revision surgery.

Rates of revision and surgeon-reported graft rupture following ACL reconstruction: early results from the New Zealand ACL Registry

PURPOSE

There remains a lack of consensus on the patient factors associated with graft rupture following anterior cruciate ligament (ACL) reconstruction. This study aimed to identify the rate of revision and surgeon-reported graft rupture and clarify the patient risk factors for failure.

METHODS

Analysis was conducted on prospective data captured by the New Zealand ACL registry. All primary isolated ACL reconstructions recorded between April 2014 and December 2018 were reviewed to identify the rate of revision and surgeon-reported graft rupture. Univariate and multivariate survival analysis was performed to identify patient factors associated with revision and graft rupture.

RESULTS

A total of 7402 primary isolated ACL reconstructions were reviewed and had a mean follow-up time of 23.1 (SD ± 13.9) months. There were 258 surgeon-reported graft ruptures (3.5%) of which 175 patients underwent subsequent revision ACL reconstruction (2.4%). Patients younger than 18 years had the highest risk of revision (adjusted HR = 7.29, p < 0.001) and graft rupture (adjusted HR = 4.26, p < 0.001) when compared to patients aged over 36 years. Male patients had a higher risk of revision (adjusted HR = 2.00, p < 0.001) and graft rupture (adjusted HR = 1.70, p < 0.001) when compared to their female counterparts. Patients who underwent ACL reconstruction within 6 months of their injury had a two times increased risk of revision compared to patients who had surgery after 12 months (adjusted HR = 2.15, p = 0.016).

CONCLUSION

Younger age, male sex and a shorter injury-to-surgery time interval increased the risk of revision, while younger age and male sex increased the risk of surgeon-reported graft rupture.

LEVEL OF EVIDENCE

II.

One in 5 Athletes Sustain Reinjury Upon Return to High-Risk Sports After ACL Reconstruction: A Systematic Review in 1239 Athletes Younger Than 20 Years

CONTEXT

Anterior cruciate ligament (ACL) reconstruction (ACLR) is frequently performed in patients younger than 20 years whose goal is to return to sport (RTS). Varying reinjury rates have been reported, and the factors responsible are unclear. Studies differ with regard to age, graft type, surgical techniques, postoperative rehabilitation, RTS guidelines, and methods used to determine ACL failures.

OBJECTIVE

To determine RTS rates; the effect of participation in high-risk sports, sex, and graft type on ACL reinjury rates; and whether objective test criteria before RTS correlate with lower reinjury rates.

DATA SOURCES

A systematic review of the literature from inception to May 31, 2019, was conducted using the PubMed and Cochrane databases.

STUDY SELECTION

Studies on transphyseal ACLR in athletes <20 years old with a minimum mean follow-up of 2 years that reported reinjury rates, the number that RTS, and detailed the type of sport were included.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 4.

RESULTS

A total of 1239 patients in 8 studies were included; 87% returned to sport and 80% resumed high-risk activities. Of the patients, 18% reinjured the ACL graft and/or the contralateral ACL. Nine percent of patellar tendon autografts and 15% of hamstring autografts failed (odds ratio [OR], 0.52; P = 0.002). Of reinjuries, 90% occurred during high-risk sports. Male patients had a significantly higher rate of ACL graft failure than female patients (OR, 1.64; P = 0.01). There was no sex-based effect on contralateral ACL injuries. Only 1 study cited objective criteria for RTS.

CONCLUSION

A high percentage of athletes returned to sport, but 1 in 5 suffered reinjuries to either knee. Male patients were more likely to reinjure the ACL graft. Objective criteria for RTS were rarely mentioned or not detailed. The need for testing of knee stability, strength, neuromuscular control, agility, and psychological measures before RTS remains paramount in young athletes.

Repair With Dynamic Intraligamentary Stabilization Versus Primary Reconstruction of Acute Anterior Cruciate Ligament Tears: 2-Year Results From a Prospective Randomized Study

BACKGROUND

Anterior cruciate ligament (ACL) repair has once again become a focus of research because of the development of new techniques.

PURPOSE/HYPOTHESIS

The purpose was to compare the functional results and recurrent instability rates in patients undergoing ACL repair with dynamic intraligamentary stabilization (DIS) versus primary ACL reconstruction (ACLR) for acute isolated ACL tears. The hypothesis was that functional results and knee joint stability after ACL repair with DIS would be comparable with that after ACLR.

STUDY DESIGN

Randomized clinical trial; Level of evidence, 1.

METHODS

A total of 85 patients with acute ACL tears were randomized to undergo either ACL repair with DIS or primary ACLR. The preinjury activity level and function were recorded. Follow-up examinations were performed at 6 weeks and 6, 12, and 24 months postoperatively. Anterior tibial translation (ATT) was evaluated using Rolimeter testing. The Tegner activity scale, International Knee Documentation Committee (IKDC) subjective form, and Lysholm knee scoring scale scores were obtained. Clinical failure was defined as ΔATT >3 mm in combination with subjective instability. Recurrent instability and other complications were recorded.

RESULTS

There were 83 patients (97.6%) who were successfully followed until 2 years. ATT was significantly increased in the DIS group compared with the ACLR group (ΔATT, 1.9 vs 0.9 mm, respectively; P = .0086). A total of 7 patients (16.3%) in the DIS group had clinical failure and underwent single-stage revision. In the ACLR group, 5 patients (12.5%) had failure of the reconstruction procedure; 4 of these patients required 2-stage revision. The difference in the failure rate was not significant (P = .432). There were 4 patients (3 in the DIS group and 1 in the ACLR group) who showed increased laxity (ΔATT >3 mm) without subjective instability and did not require revision. Recurrent instability was associated with young age (<25 years) and high Tegner scores (>6) in both groups. No significant differences between ACL repair with DIS and ACLR were found for the Tegner, IKDC, and Lysholm scores at any time.

CONCLUSION

Whereas ATT measured by Rolimeter testing was significantly increased after ACL repair with DIS, clinical failure was similar to that after ACLR. In addition, functional results after ACL repair with DIS for acute tears were comparable with those after ACLR. The current study supports the use of ACL repair with DIS as an option to treat acute ACL tears.

REGISTRATION

DRKS00015466 (German Clinical Trials Register).

Comparing Hamstring Autograft With Hybrid Graft for Anterior Cruciate Ligament Reconstruction: A Systematic Review

PURPOSE

To systematically review the literature in an effort to compare the demographics and clinical outcomes of patients undergoing anterior cruciate ligament reconstruction (ACLR) with a hamstring tendon autograft (HT) versus an irradiated or nonirradiated hybrid autograft-allograft.

METHODS

A systematic review of the PubMed, Cochrane Library, and Embase databases was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. All English-language literature that reported general demographics and compared the clinical outcomes of patients undergoing primary ACLR with autograft versus hybrid graft (HG) with a minimum 2-year follow-up was reviewed by 2 independent reviewers. Search terms used were "anterior cruciate ligament" and "hybrid graft." Patients were assessed based on graft failure, anteroposterior laxity, and patient-reported outcomes (Knee Injury and Osteoarthritis Outcome Score, visual analog scale, Subjective International Knee Documentation Committee score, Lysholm, and Tegner scores). Study quality was evaluated with the Modified Coleman Methodology Score and ROBINS-I risk of bias tool.

RESULTS

Twelve studies (1 level II, 11 level III) met inclusion criteria (follow-up, 2.0-8.9 years), including 471 patients undergoing ACLR with an irradiated hybrid graft (IH), 89 patients with a nonirradiated hybrid graft, and 829 patients with HT. Graft diameter ranged from 7.5 to 10.0 mm and from 6.5 to 10.0 mm in HG and HT patients, respectively. Overall, graft failure ranged from 0% to 30.0% and from 0% to 28.3% in HG and HT patients, respectively (I² = 35.9%; 95% confidence interval 0%-74.8%). Among HG patients, graft failure ranged from 0%-30.0% and from 2.4%-4.2% in IH and nonirradiated hybrid graft groups, respectively (I² = 33.6%; 95% confidence interval, 0%-71.8%). Results for postoperative anteroposterior laxity and patient-reported outcomes were also inconsistent.

CONCLUSIONS

Patients undergoing ACLR with HT demonstrate inconsistent differences in clinical outcomes at midterm follow-up compared with IH patients.

LEVEL OF EVIDENCE

III, systematic review of level II and III studies.

Factors associated with revision following anterior cruciate ligament reconstruction: A systematic review of registry data

BACKGROUND

To identify the patient and surgical factors associated with revision anterior cruciate ligament (ACL) reconstruction as reported by all national and community ACL registries.

METHODS

A systematic review was performed on the MEDLINE, Embase and Cochrane Library databases. Eligibility criteria included English studies published by national or community ACL registries reporting on primary ACL reconstruction and risk factors associated with revision ACL reconstruction.

RESULTS

Thirty-three studies from the Swedish, Norwegian, Danish and Kaiser Permanente registries were included for review. Fourteen studies from all four registries reported younger age as a risk factor for revision ACL reconstruction. In addition, the Swedish registry reported concomitant medial collateral ligament (MCL) injury, undergoing earlier surgery, lower Knee Injury and Osteoarthritis Outcome Score (KOOS), smaller graft diameter and an anteromedial portal drilling technique as risk factors for revision. The risk factors reported by the Norwegian registry included lower body mass index (BMI), lower KOOS, hamstring tendon grafts and suspensory fixation. The Danish registry reported hamstring tendon grafts, anteromedial portal drilling and suspensory fixation as risk factors. The Kaiser Permanente registry reported male sex, lower BMI, ethnicity, hamstring tendon grafts, allografts, smaller graft diameter and an anteromedial portal technique as risk factors for revision.

CONCLUSION

Multiple patient and surgical factors were associated with increased risk of revision ACL reconstruction in registries. Younger age and the use of hamstring tendon grafts were consistently reported as risk factors for failure.

Higher frequency of osteoarthritis in patients with ACL graft rupture than in those with intact ACL grafts 30 years after reconstruction

PURPOSE

The aim was to assess the results of anterior cruciate ligament (ACL) reconstruction regarding graft failure, knee laxity, and osteoarthritis (OA) from a longterm perspective. It was hypothesized that intact ACL graft reduces the risk for increased OA development.

METHODS

The cohort comprised 60 patients with a median follow-up 31 (range 28-33) years after ACL reconstruction. They were evaluated with magnetic resonance imaging, radiography, KT-1000 arthrometer and the pivot shift test.

RESULTS

Out of the 60 patients, 30 (50%) showed an intact ACL graft and 30 (50%) a ruptured or absent ACL graft. Patients with ruptured ACL grafts had more medial tibiofemoral compartment OA than those with an intact ACL graft (p = 0.0003). OA was asymmetric in patients with ruptured ACL grafts with more OA in the medial than in the lateral tibiofemoral compartment (p = 0.013) and the patellofemoral compartment (p = 0.002). The distribution of OA between compartments was similar in patients with an intact ACL graft. KT-1000 values of anterior knee laxity were higher in patients with ruptured compared to those with intact ACL grafts (p = 0.012). Side-to-side comparisons of anterior knee laxity showed higher KT-1000 values in patients with ruptured ACL graft (p = 0.0003) and similar results in those with intact graft (p = 0.09). The pivot shift grade was higher in the group with a ruptured ACL graft (p < 0.0001).

CONCLUSIONS

Median 31 (range 28-33) years after ACL reconstruction, 50% of the patients showed an intact ACL graft and no side-to-side difference regarding anterior knee laxity. Patients with ruptured ACL grafts had more OA of the medial tibiofemoral compartment than those with intact ACL grafts.

LEVEL OF EVIDENCE

Retrospective cohort study, Level III.

Anterior Cruciate Ligament Reconstruction With Suture Tape Augmentation: A Surgical Technique

The anterior cruciate ligament (ACL) is the most common ligamentous knee injury and often is encountered in those participating in multidirectional sports. ACL reconstruction is the most commonly performed knee ligament reconstruction and employs a variety of surgical techniques but still is challenged by residual laxity and graft rupture. To help address and prevent future ACL failures, new repair and reconstruction techniques have been employed that incorporate suture augmentation (InternalBrace; Arthrex, Naples, FL), which protects the graft during healing and ligamentization. Our goal of this article is to provide a surgical technique of suture augmentation with ACL reconstruction.

Risk Factors for Revision Anterior Cruciate Ligament Reconstruction and Frequency With Which Patients Change Surgeons

Background:

Revision surgery is a known complication after anterior cruciate ligament (ACL) reconstruction (ACLR), but the proportion of patients who seek a different surgeon for their revision procedure is unknown.

Purpose:

To determine the rate and risk factors for revision ACLR in New Zealand and to find the proportion of patients undergoing revision ACLR who see a different surgeon compared with their primary procedure as well as the factors that may influence this decision.

Study Design:

Case series; Level of evidence, 4.

Methods:

Data from New Zealand’s single government insurer, the Accident Compensation Corporation (ACC), were analyzed. All primary ACLR procedures performed between January 1, 2009, and December 31, 2014 were evaluated, and revision ACLR procedures performed between January 1, 2009, and December 31, 2016, were evaluated to allow for a minimum 2-year follow-up period. Cases undergoing subsequent revision were divided into those with the same or a different surgeon compared with the primary procedure. Risk factors for revision and change of surgeons were assessed, including age, sex, time from injury to surgery, time between primary and revision procedures, surgeon volume, and ethnicity.

Results:

A total of 15,212 primary ACLR procedures were recorded in 14,926 patients. The mean patient age was 29.2 years, and 61% were male patients. There were 676 subsequent revision procedures and 510 contralateral procedures during the study period, resulting in a 5-year survival rate of 95.5% for the ACL graft and 96.5% for the contralateral ACL. Risk factors for revision surgery included male sex, age <20 years, and <1 year from injury to surgery. Of the revision procedures, 44.5% (n = 301) were performed by a different surgeon compared with primary ACLR. For primary ACLR procedures performed by low-volume surgeons, 75.0% of patients requiring revision ACLR changed surgeons, compared with 21.5% for high-volume surgeons (≤10 vs >50 primary ACLR/y; hazard ratio, 10.70 [95% CI, 6.01-19.05]; P < .001). Other factors associated with change of surgeons included older age, longer time between primary and revision surgery, and Asian and Maori ethnicities.

Conclusion:

A significant proportion of patients change surgeons when requiring revision ACLR. In the absence of formal follow-up systems such as registries, surgeons, particularly those with a low volume of ACLRs, may underestimate their personal revision rate.

Peroneus longus autograft can be recommended as a superior graft to hamstring tendon in single-bundle ACL reconstruction

PURPOSE

A peroneus longus tendon autograft is used in many orthopaedic procedures and it is biomechanically comparable to a hamstring tendon autograft. Despite its potential, there are few studies that have evaluated the use of the peroneus longus tendon in ACL reconstruction. The aim of this study was to compare the clinical outcome and donor site morbidity of ACL reconstruction with hamstring tendon autografts versus peroneus longus tendon autografts in patients with an isolated ACL injury.

METHODS

Patients who underwent isolated single-bundle ACL reconstruction were allocated to two groups (hamstring and peroneus longus) and observed prospectively. Graft diameter was measured intraoperatively. Functional scores (IKDC, modified Cincinnati and Lysholm scores) were recorded preoperatively and 1 year after surgery. Donor site morbidities were assessed with thigh circumference measurements and ankle scoring with the AOFAS and FADI.

RESULTS

Fifty-two patients (hamstring n = 28, peroneus n = 24) met the inclusion criteria. The peroneus longus graft diameter (8.8 ± 0.7 mm) was significantly larger than the hamstring diameter (8.2 ± 0.8 mm) (p = 0.012). There were no significant differences between the pre- and 1-year postoperative score between the hamstring and peroneus longus groups in the IKDC (n.s), modified Cincinnati (n.s), and Lysholm (n.s). The mean for the AOFAS was 97.3 ± 4.2 and for the FADI 98 ± 3.4 in the peroneus longus group, with a significant decrease in thigh circumference in the hamstring group (p = 0.002).

CONCLUSION

Anterior cruciate ligament reconstruction with peroneus longus autografts produces a functional score (IKDC, modified Cincinnati, Lysholm) comparable to that of hamstring autografts at a 1-year follow-up, with the advantages of larger graft diameter, less thigh hypotrophy and excellent ankle function based on AOFAS and FADI scores.

LEVEL OF EVIDENCE

Prospective cohort study, Level II.

Hand-held dynamometer identifies asymmetries in torque of the quadriceps muscle after anterior cruciate ligament reconstruction

PURPOSE

To verify the validity and diagnostic accuracy of the hand-held dynamometer (HHD) with the isokinetic dynamometer for evaluating the quadriceps strength of subjects who have undergone ACL reconstruction (ACLR).

METHODS

This validity and diagnostic accuracy study was conducted prospectively by examining 70 consecutive participants who had undergone ACLR at least 6 months previously. All participants performed strength evaluation of the quadriceps muscle using the HHD and isokinetic dynamometer.

RESULTS

The HHD presented high test-retest reliability [intraclass correlation coefficient (ICC) = 0.98], moderate to good validity with the isokinetic dynamometer when compared for the quadriceps strength (r = 0.62), 100% perfect specificity [LR + infinity, 95% confidence interval (CI) 81.4%-100%] to identify those with LSI > 10%, and a sensitivity of 63.4% (48.9%-76.3%).

CONCLUSION

The HHD is an instrument valid and reliable of low cost and easy handling compared to the isokinetic dynamometer to evaluate the quadriceps torque and the limb symmetry index after the ACLR with high diagnostic accuracy.

LEVEL OF EVIDENCE

I.

Re-revision Anterior Cruciate Ligament Reconstruction: An Evaluation From the Norwegian Knee Ligament Registry

PURPOSE

To identify the rate of re-revision anterior cruciate ligament reconstruction (ACLR) to estimate the influence of patient-related factors on the risk of re-revision ACLR. The secondary aim of the study was to report the intra-articular findings and patient-related factors at the time of revision ACLR and to compare these with the findings in a matched controlled group of primary ACLR.

METHODS

Patients with primary ACLR without a subsequent need of revision and patients with a revision ACLR identified in the Norwegian Knee Ligament Registry from June 2004 through September 2016 were included. Using age at operation, sex, activity at injury, and year of ACLR as covariates, a propensity score matched control group of primary ACLR patients for the revision ACLR patients was identified. For the revision ACLR patients, re-revision ACLR rates at 1, 2, 5, and 8 years were estimated with Kaplan-Meier analysis; the hazard ratio for a re-revision ACLR was estimated using a multivariable Cox regression model.

RESULTS

The cumulative estimated proportion of patients undergoing a re-revision ACLR at 1, 2, 5, and 8 years after the original revision ACLR was 0.4%, 3.0%, 6.5%, and 9.0% respectively. There was no significant difference between the control and revision ACLR groups regarding cartilage injury (P = .72) or associated ligament injury (P = .17). Revision ACLR patients did have fewer meniscal injuries (P < .001). There were no intraoperative findings or surgical techniques identified as a predictor for a higher risk of re-revision ACLR.

CONCLUSIONS

Based on a review of a large ligament reconstruction registry,one can expect 9% of patients to undergo a re-revision ALCR at 8 years of follow up. Revision ACLR did not have an increase in cartilage injuries or associated ligament injuries and had significantly fewer meniscal injuries compared with a primary ACLR control group.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Improved results of ACL primary repair in one-part tears with intact synovial coverage

PURPOSE

It was the aim to assess the influence of synovial sheath disruption on early failure of primary anterior cruciate ligament (ACL) repair. It was hypothesized that more-part ACL tears with disruption of the synovial sheath are associated with a higher risk of failure after primary ACL repair.

METHODS

A cohort study was conducted comprising patients with primal ACL tears undergoing primary ACL repair and dynamic intraligamentary stabilization (DIS). The patients were stratified into three groups: A-one-part rupture with intact synovial membrane (n = 50), B-two-part ruptures resultant to separation of the ACL into two main bundles with synovial membrane tearing (n = 52) and C-more parts involving multilacerated ruptures with membrane disruption (n = 22). Failure was defined as a retear or residual laxity (anterior posterior translation > 5 mm compared to healthy knee). Adjustment for potential risk factors was performed using a multivariate logistic-regression model.

RESULTS

The overall failure rate was 17.7% throughout the mean follow-up period of 2.3 ± 0.8 years. The failure rate in patients with one-part ACL tears with an intact synovial membrane was 4% (n = 2) (Group A), which was significantly lower than the failure rates in groups B and C, 26.9% (n = 14) (p = 0.001) and 27.3% (n = 6) (p = 0.003), respectively. Disruption of the synovial sheath in two- or more-part tears was identified as an independent factor influencing treatment failure in primary ACL repair (OR 8.9; 95% CI 2.0-40.0).

CONCLUSION

The integrity of the ACL bundles and synovial sheath is a factor that influences the success of ACL repair. This needs to be considered intra-operatively when deciding about repair.

LEVEL OF EVIDENCE

IV.

Surgeon experience with dynamic intraligamentary stabilization does not influence risk of failure

PURPOSE

Studies on dynamic intraligamentary stabilization (DIS) of acute anterior cruciate ligament (ACL) ruptures reported failure rates similar to those of conventional ACL reconstruction. This study aimed to determine whether surgeon experience with DIS is associated with revision rates or patient-reported outcomes. The hypothesis was that more experienced surgeons achieved better outcomes following DIS due to substantial learning curve.

METHODS

The authors prospectively enrolled 110 consecutive patients that underwent DIS and evaluated them at a minimum of 2 years. The effects of independent variables (surgeon experience, gender, age, adjuvant procedures, tear location, preinjury Tegner score, time from injury to surgery, and follow-up) on four principal outcomes (revision ACL surgery, any re-operation, IKDC and Lysholm score) were analyzed using univariable and multivariable regressions.

RESULTS

From the 110 patients enrolled, 14 patients (13%) were lost to follow-up. Of the remaining 96 patients, 11 underwent revision ACL surgery, leaving 85 patients for clinical assessment at a mean of 2.2 ± 0.4 years (range 2.0-3.8). Arthroscopic reoperations were performed in 26 (27%) patients, including 11 (11%) revision ACL surgeries. Multivariable regressions revealed: (1) no associations between the reoperation rate and the independent variables, (2) better IKDC scores for 'designer surgeons' (b = 10.7; CI 4.9-16.5; p < 0.001), higher preinjury Tegner scores (b = 2.5, CI 0.8-4.2; p = 0.005), and younger patients (b = 0.3, CI 0.0-0.6; p = 0.039), and (3) better Lysholm scores for 'designer surgeons' (b = 7.8, CI 2.8-12.8; p = 0.005) and preinjury Tegner score (b = 1.9, CI 0.5-3.4; p = 0.010).

CONCLUSION

Surgeon experience with DIS was not associated with rates of revision ACL surgery or general re-operations. Future, larger-scaled studies are needed to confirm these findings. Patients operated by 'designer surgeons' had slightly better IKDC and Lysholm scores, which could be due to better patient selection and/or positively biased attitudes of both surgeons and patients.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

One-Stage Revision Anterior Cruciate Ligament Reconstruction: Results According to Preoperative Bone Tunnel Diameter: Five to Fifteen-Year Follow-up

BACKGROUND

Bone tunnel enlargement is one of the important factors that determine whether a revision anterior cruciate ligament reconstruction (ACLR) should be performed in 1 or 2 stages. The goal of this retrospective cohort study was to compare the mid-term to long-term outcomes of 1-stage revision ACLR according to the amount of preoperative tunnel enlargement.

METHODS

Between January 2002 and January 2012, 88 patients who underwent revision ACLR were enrolled. The patients were divided into 2 groups based on the tunnel diameter (group A, <12 mm; group B, ≥12 mm). Clinical scores (International Knee Documentation Committee [IKDC] subjective score, Lysholm score, and Tegner score) and knee joint stability (as measured with the anterior drawer test, Lachman test, pivot-shift test, and measurement of the side-to-side difference in anterior tibial translation on Telos stress radiographs) were evaluated preoperatively and 5 to 15 years postoperatively. The failure rate and survivorship were compared between groups A and B.

RESULTS

The mean time to final follow-up was 7.9 ± 2.6 years. There were 44 patients in each of the 2 groups. There were no significant differences in the postoperative IKDC subjective scores, Lysholm scores, or Tegner activity scores between the groups. However, group A showed superior results on all knee joint stability tests except for the anterior drawer test. There were 3 failures in group A (7%) and 6 in group B (14%). The overall survival rates with failure as the end point were 93.1% and 84.6%, respectively, at 15 years.

CONCLUSIONS

The 5 to 15-year clinical scores following revision ACLR did not differ significantly according to the preoperative amount of tunnel widening. However, the results of the postoperative Lachman and pivot-shift tests as well as the side-to-side difference in anterior tibial translation on Telos stress radiographs were significantly superior in the group with a preoperative tunnel diameter of <12 mm compared with the group with a tunnel diameter of ≥12 mm.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.