Good mid-term outcomes and low rates of residual rotatory laxity, complications and failures after revision anterior cruciate ligament reconstruction (ACL) and lateral extra-articular tenodesis (LET)

Considerations for revision anterior cruciate ligament reconstruction: A review of the current literature

Background

Failure rates among primary Anterior cruciate ligament reconstruction 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.

Methods

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.

Results

In revision ACLR patients, those receiving autografts are 2.78 times less likely to experience a re-rupture compared to patients who receive allografts. Additionally, individuals with properly positioned tunnels and removable implants are considered strong candidates for one-stage revision procedures. Conversely, cases involving primary tunnel widening of approximately 15 mm are typically indicative of two-stage revision ACLR. These findings underscore the importance of graft selection and surgical approach in optimizing outcomes for patients undergoing revision ACLR.

Conclusion

Given the high rates of revision surgery in young, active patients who return to pivoting sports, the literature recommends strong consideration of a combined ACLR + anterolateral ligament (ALL) or lateral extra-articular tenodesis (LET) procedure in this population. Unrecognized posterolateral corner (PLC) injury is a common cause of ACLR failure and current literature suggests concurrent operative management of high-grade PLC injuries. Excessive PTS has been identified as an independent risk factor for ACL graft failure. Consider revision ACLR with combined slope-reducing tibial osteotomy in cases of posterior tibial slope greater than 12°.

Combined Anterolateral Ligament Reconstruction Results in Better Knee Stability and More Satisfactory Subjective Outcomes in Non-Athlete Patients Undergoing Revision Anterior Cruciate Ligament Reconstruction

Background: Consensus has not yet been reached regarding combined anterior cruciate ligament reconstruction (ALLR) with revisional anterior cruciate ligament reconstruction (RACLR). We aimed to compare the clinical outcomes between patients who underwent isolated RACLR and those who underwent RACLR combined with ALLR. Methods: Between June 2010 and June 2021, 49 patients who underwent RACLR were retrospectively reviewed over a 24-month follow-up. Patients were categorized into the isolated RACLR (n = 37, group 1) or combined ALLR group (n = 12, group 2). Clinical outcomes were evaluated with several patient-reported outcome measures (PROMs) and minimal clinically important differences (MCIDs) for each PROM. The side-to-side difference (SSD) of the anterior instability was measured. The pivot-shift test was performed. Results: Baseline characteristics showed no differences between the groups. PROMs showed no significant differences between the groups at the 2-year follow-up. Group 2 was superior to group 1 in the MCID achievement rate for Lysholm knee and International Knee Documentation Committee (IKDC) subjective scores at 24 months postoperatively. At the final follow-up, the proportion of IKDC grade A in SSD for anterior laxity was higher in group 2 than in group 1 (58.3% versus [vs.] 18.3%, p = 0.009), and the proportion of pivot-shift grade 0 was also higher in group 2 (66.7% vs. 27.0%, p = 0.013). The "near return to activity" rate was also higher in group 2 than in group 1 (83.3% vs. 45.9%, p = 0.043). Conclusions: Combining ALLR with RACLR in non-athletes results in a higher proportion of patients with less mechanical graft failure and satisfactory clinical outcomes.

Revision Anterior Cruciate Ligament Reconstruction and Associated Procedures

Failure of anterior cruciate ligament reconstruction (ACLR) is a common yet devastating complication due to inferior clinical outcomes associated with revision ACLR. Identifying the cause and associated risk factors for failure is the most important consideration during preoperative planning. Special attention to tunnel quality, concomitant injuries, and modifiable risk factors will help determine the optimal approach and staging for revision ACLR. Additional procedures including lateral extra-articular tenodesis and osteotomy may be considered for at-risk populations. The purpose of this review is to explore causes of ACLR failure, clinical indications and appropriate patient evaluation, and technical considerations when performing revision ACLR.

Lateral extra-articular tenodesis does not enhance ACL graft healing, however, does reduce graft tunnel widening

PURPOSE

The study hypothesized that the addition of lateral extra-articular tenodesis (LEAT) in anterior cruciate ligament reconstruction (ACLR) had a significant effect on ACL graft healing.

METHODS

A total of 80 patients were divided into two cohorts matched for gender, age, body mass index, time from surgery to post-operative MRI and graft diameter. Forty patients underwent ACL reconstruction alone, while 40 underwent ACLR in addition to LEAT. Patients underwent a magnetic resonance imaging scan at 12 months post-surgery; tunnel apertures were measured using multiplanar reformation, graft healing was assessed using signal-to-noise quotient (SNQ) in three regions of interest and finally graft maturity and integration were classified using the Howell and Ge scale, respectively. In addition, clinical evaluation and patient-reported outcome measures were collected.

RESULTS

The mean femoral tunnel widening at 12 months post-surgery was 39.8 ± 14.0% in the ACLR + LEAT group and 55.2 ± 12.7% in the ACLR alone group (p < 0.05). The mean tibial tunnel widening was 29.3 ± 12.7% in the ACLR + LEAT group and 44.4 ± 12.1% in the ACLR group (p < 0.05). The mean adjusted graft SNQ was 9.0 ± 14.9 in the ACLR + LEAT group and 9.5 ± 11.4 in the ACLR group (n.s.).

CONCLUSION

At 1 year post-operatively, we noted significantly less femoral and tibial tunnel widening in the ACLR + LEAT group. LEAT did not result in a statistically significant effect on graft healing.

LEVEL OF EVIDENCE

Level III.

Meniscal allograft transplantation (MAT) combined with revision ACL reconstruction and lateral extra-articular tenodesis results in significantly improved outcomes, but patient-reported knee function is inferior compared to an isolated MAT

PURPOSE

Meniscal allograft transplantation (MAT) is a valuable option for postmeniscectomy syndrome in young and active patients, which can successfully improve symptoms, function and quality of life. This study aimed to report outcomes and complications in patients treated with isolated MAT or MAT combined with revision anterior cruciate ligament reconstruction (ACLR) and lateral extra-articular tenodesis (LET).

METHODS

In total, 18 patients who were treated with MAT using a soft tissue fixation technique were retrospectively analysed. Patients were allocated into two groups, the isolated MAT group and the MAT plus revision ACLR + LET group (MAT+ group). Both groups were assessed using the following Patient-Reported Outcome Measures (PROMs): Knee Injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee (IKDC), Tegner Activity Scale, Lysholm score, EuroQol 5-Dimension 5-level (EQ-5D-5L) questionnaire and a patient acceptable symptom state (PASS) statement.

RESULTS

The mean follow-up was 3.2 years and the mean age of patients was 29 (±7.6) years. Ten patients were treated with isolated MAT and eight patients were treated with MAT combined with revision ACLR and LET. No complications and no reoperations were reported. In both groups, all PROMs significantly improved postoperatively (p < 0.05), except for the Tegner score in the MAT+ group, which did not reach statistical significance (not significant [n.s.]). No significant difference was found postoperatively in PROMs between the MAT and the MAT+ group; however, differences in the KOOS Symptoms, Sports and Quality-of-life subscales reached the minimal clinically important threshold. Mean values were: IKDC 61.2 (±13.9) versus 64.7 (±23.2), KOOS Total 72.8 (±14.9) versus 68.0 (±16.7), Lysholm score 83.2 (±11) versus 84.2 (±8.7) and EQ-5D-5L 71.8 (±14.9) versus 72.2 (±22.4). Median values for the Tegner Activity Scale were 4 versus 3. PASS statement was negative in 37.5% of the MAT+ group in comparison to 20% of the MAT group (n.s.).

CONCLUSION

In terms of patient-reported outcomes, MAT is an effective and safe procedure, even when combined with revision ACLR + LET. Compared to the preoperative assessment, a significant improvement of the postoperative PROMs can be expected either when MAT is performed isolated or in combination with ACLR + LET. However, clinically important differences between the two groups can be noted in favour of the isolated MAT procedure, especially regarding symptoms and sporting activity.

LEVEL OF EVIDENCE

Level III.

Evaluation of Anterior Tibial Translation Under Physiological Axial Load After ACL Reconstruction With Lateral Extra-articular Tenodesis

Background

Postoperative laxity correlates with negative clinical outcomes after anterior cruciate ligament reconstruction (ACLR). The influence of lateral extra-articular tenodesis (LET) on anteroposterior translation is unclear.

Purpose/Hypothesis

This study aimed to evaluate the reduction in radiographic static anterior tibial translation (SATT) and dynamic anterior tibial translation (DATT) after LET as an adjunctive procedure to ACLR. It was hypothesized that adding a LET procedure would have no effect on postoperative SATT and DATT.

Study Design

Cohort study; Level of evidence, 3.

Methods

Patients who underwent primary ACLR with hamstring tendon autografts between 2020 and 2022 were reviewed, and those who underwent ACLR and LET as an anterolateral associate procedure were paired 1 to 1 with those who underwent isolated ACLR (control) based on age, sex, preoperative SATT, and posterior tibial slope (PTS). The indications for LET were age <18 years and anterolateral rotary instability (grade ≥2 pivot shift). A previously validated technique was used to measure SATT, DATT, and PTS on lateral weightbearing and lateral stress knee radiographs. Preoperative and 9-month postoperative radiographs were compared between the 2 groups.

Results

A total of 72 patients were included in the analysis (n = 36 patients in each group). The inter- and intraobserver reliability of the SATT, DATT, and PTS measurements was excellent (intraclass correlation coefficients, 0.88-0.99). The mean pre- and postoperative SATT in the ACLR+LET group was 2.44 ± 2.90 mm and 2.44 ± 2.38 mm, respectively, compared with 2.60 ± 2.99 mm and 2.12 ± 2.74 mm, respectively, in the control group. The mean pre- and postoperative reduction in side-to-side DATT in the ACLR+LET group was 5.44 ± 4.65 mm and 1.13 ± 2.95 mm, respectively, compared with 5.03 ± 3.66 mm and 2 ± 3.12 mm, respectively, in the control group. There was no pre- to postoperative difference in SATT (P = .51). However, the side-to-side DATT was reduced by 3.66 ± 3.37 mm postoperatively (P < .001), without significant differences between groups (P = .24).

Conclusion

Including a LET procedure for patients undergoing ACLR did not reduce SATT; that is, it did not decrease the amount of tibial translation due to physiological axial load.

Can lateral tenodesis improve the rotational stability of the ACL reconstruction? A finite element analysis

One of the most common knee injuries is the Anterior Cruciate Ligament (ACL) rupture with severe implications on knee stability. The usual treatment is the ACL Reconstruction (ACLR) surgery where the surgeon replaces the torn ligament with a graft in an effort to restore knee kinematics. In case of excessive rotatory instability, Lateral Extra-Articular Tenodesis (LET) can be performed in combination with ACLR. Additionally, LET appears to reduce ACLR graft forces minimizing graft failure chances. However, there are concerns about overconstraining physiological rotation. To gain insight in this controversial topic, we developed an automatic, open-source tool to create a series of Finite Element (FE) models attempting to investigate the interactions of ACLR and LET through simulation. We started by creating a validated model of the healthy knee joint that served as reference for subsequent FE simulations. Then, we created FE models of standalone ACLR and combined ACLR-LET. Each model was assessed by applying a loading profile that resembles the reduction phase of the Pivot-Shift clinical exam. We measured the External Tibia Rotation (ETR), the Posterior Tibia Translation (PTT) of the lateral tibial compartment, and the ACLR graft stress developed around the femoral tunnel insertion site. We observed the following: a) LET reduces ETR and PTT compared to isolated ACLR, b) combined ACLR-LET is more sensitive to LET graft pretension with lower values showcasing performance closer to the healthy joint, c) LET reduces ACLR graft forces for the same pretension values, d) LET exhibits significant overconstraint for higher pretension values. In general, these findings are in agreement with relevant clinical studies and accentuate the potential of the developed framework as a tool that can assist orthopaedists during surgery planning. We provide open access for the FE models of this study to enhance research transparency, reproducibility and extensibility.

The Role of Anterolateral Ligament Reconstruction or Lateral Extra-articular Tenodesis for Revision Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-analysis of Comparative Clinical Studies

BACKGROUND

After its success in restoring rotational stability and reducing failure rates in primary anterior cruciate ligament reconstruction (ACLR), lateral extra-articular tenodesis (LET) or anterolateral ligament reconstruction (ALLR) has been endorsed for use in revision ACLR surgery, where failure rates are historically higher.

PURPOSE

To perform a systematic review and meta-analysis on whether the addition of a LET or ALLR results in superior clinical outcomes and stability compared with isolated revision ACLR (iACLR).

STUDY DESIGN

Meta-analysis; Level of evidence, 4.

METHODS

The Cochrane Controlled Register of Trials, PubMed, Medline, and Embase were used to perform a systematic review and meta-analysis of comparative studies using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) criteria with the following search terms: ("extra-articular" OR "tenodesis" OR "anterolateral ligament" OR "iliotibial") AND ("anterior cruciate ligament") AND ("revision" OR "re-operation"). Data pertaining to all patient-reported outcome measures (PROMs), rotational stability, and postoperative complications were extracted from each study.

RESULTS

After abstract and full-text screening, 10 clinical comparative studies were included. There were 793 patients, of whom 390 had an iACLR while 403 had an ACLR augmented with a LET or an ALLR (augmented ACLR [aACLR]). The mean time for assessment of PROMs was 35 months. The aACLR group had superior International Knee Documentation Committee (IKDC) scores (standardized mean difference [SMD], 0.27; 95% CI, 0.01 to 0.54; P = .04), rotational stability (odds ratio [OR], 2.77; 95% CI, 1.91 to 4.01; P < .00001), and lower side-to-side difference (OR, -0.53; 95% CI, -0.81 to -0.24; P = .0003) than those without the augmentation. Furthermore, they were less likely to fail (OR, 0.44; 95% CI, 0.24 to 0.80; P = .007). Subgroup analysis in the higher-grade laxity cohort (grade ≥2) revealed an even greater IKDC score (SMD, 0.51; 95% CI, 0.16 to 0.86; P = .005) and an improved Lysholm score (SMD, 0.45; 95% CI, 0.24 to 0.67; P < .0001) in the aACLR group.

CONCLUSION

Revision aACLR with a LET or an ALLR can improve subjective IKDC scores, restore rotational stability, and reduce failure rates compared with iACLR. Although controversy remains on the necessity of augmenting all revision ACLRs, the present meta-analysis advocates adding a lateral procedure, particularly in those with a higher-grade pivot shift.

Management of anterior cruciate ligament revision in adults: the 2022 ESSKA consensus: part II-surgical strategy

PURPOSE

The aim of this ESSKA consensus is to give recommendations based on scientific evidence and expert opinion to improve the diagnosis, preoperative planning, indication and surgical strategy in Anterior Cruciate Ligament revision.

METHODS

Part 2, presented herein, followed exactly the same methodology as Part 1: the so-called ESSKA formal consensus derived from the Delphi method. Eighteen questions were ultimately asked. The quality of the answers received the following grades of recommendation: Grade A (high level scientific support), Grade B (scientific presumption), Grade C (low level scientific support) or Grade D (expert opinion). All answers were scored from 1 to 9 by the raters. Once a general consensus had been reached between the steering and rating groups, the question-answer sets were submitted to the peer-review group. A final combined meeting of all the members of the consensus was then held to ratify the document.

RESULTS

The review of the literature revealed a rather low scientific quality of studies examining the surgical strategy in cases of ACL reconstruction failure. Of the 18 questions, only 1 received a Grade A rating; 5, a Grade B rating; and 9, grades of C or D. The three remaining complex questions received further evaluations for each portion of the question and were looked at in more detail for the following grades: B and D; A, C and D; or A, B, C and D. The mean rating of all questions by the rating group was 8.0 + - 1.1. The questions and recommendations are listed in the article.

CONCLUSION

ACL revision surgery, especially the surgical strategy, is a widely debated subject with many different opinions and techniques. The literature reveals a poor level of standardization. Therefore, this international European consensus project is of great importance and clinical relevance for guiding the management of ACL revision in adults.

LEVEL OF EVIDENCE

Level II.

Combined anterior cruciate ligament revision with reconstruction of the antero-lateral ligament does not improve outcome at 2-year follow-up compared to isolated acl revision; a randomized controlled trial

PURPOSE

It is essential to obtain rotational stability of the knee after anterior cruciate ligament reconstruction (ACL-R) and it is suggested that a supplementary reconstruction of the antero-lateral ligament (ALL-R) may supports this. Theoretically, ALL-R may be particularly advantageous to support revision of failed ACL-Rs. It was hypothesized that ACL revision combined with ALL-R will result in superior outcome compared to isolated ACL revision.

METHODS

The study was designed as a randomized controlled trial. Patients eligible for first time ACL revision were randomized to either isolated ACL revision (- ALL group) or ACL revision combined with a single-stranded allograft ALL-reconstruction (+ ALL group). Patient reported outcomes and function were evaluated at two-year follow-up by KNEES-ACL, KOOS, and Tegner activity scale. Objective knee laxity was evaluated at one-year follow-up using an instrumented Rolimeter test, the pivot shift test, and a manual Lachman test.

RESULTS

A total of 103 patients were enrolled with 49 patients randomized to the + ALL group and 54 patients in the - ALL group. There were no differences at baseline between groups regarding age, gender, body mass index, preoperative patient reported outcome scores and concomitant meniscus or cartilage injury. The ACL revision was performed with an allograft in 10 patients (20%) in the + ALL group and 8 patients (15%) in the -ALL group. At follow-up there was no significant difference between the groups in patient reported outcome scores and clinical knee laxity.

CONCLUSION

Supplementary ALL-R does not improve subjective outcome of first time ACL revision at two-years and clinical knee stability at one-year follow-up compared to isolated ACL revision.

LEVEL OF EVIDENCE

Level I.

Good rates of return-to-sport in athletes after revision anterior cruciate ligament reconstruction using autologous patellar tendon and lateral extra-articular tenodesis: a 2-year follow-up prospective study

BACKGROUND

Most athletes who undergo revision of the anterior cruciate ligament reconstruction (ACLR) aim to return to their preinjury sport at a similar level of performance while minimizing the risk for reinjury. Additional lateral extra-articular tenodesis (LET) has recently been correlated with improved outcomes and low complication rate. Yet, there are few series evaluating return-to-sport (RTS) and clinical outcomes after revision ACLR using bone-patellar tendon-bone (BPTB) and LET in athletes.

METHODS

The study cohort consisted of 19 eligible athletes who had undergone their first revision ACLR using BPTB and LET (modified Lemaire) between January 2019 and 2020. Patients were prospectively followed and interviewed in a sports activity survey during a 2-year follow-up.

RESULTS

Despite all patients returning to sports after revision ACLR surgery, 52.6% resumed playing at their preinjury level. Furthermore, patient-reported functional outcomes improved significantly following revision surgery, as evidenced by improvements in IKDC [64.4 (± 12) to 87.8 (± 6)], Lysholm [71.27 (± 12) to 84.2 (± 9.7)], and SF-12 scales [Physical: 53.3 (± 3) 57 (± 1.2); Mental: 50.2 (± 3.3) to 52.7 (± 2.4)]. One case (5.3%) experienced persistent pain and underwent reoperation for a partial meniscectomy.

CONCLUSION

After revision ACLR using autologous BPTB and LET, all active individuals are expected to RTS, similar to primary ACLR. The difference comes down to returning to the preinjury level, where the levels are lower depending on the sport and initial level of play. Good mid-term functional outcomes with a low complication rate can be expected in most cases.

STUDY DESIGN

Case series; Level of evidence IV.

ETHICAL COMMITTEE APPROVAL NUMBER

PR(ATR)79/2021 and HCB/2023/0173.

Additional Anterolateral Ligament Reconstruction Helps Patients Improve Dynamic Postural Stability in Revision Anterior Cruciate Ligament Reconstruction

Background and Objectives: The goal in treating anterior cruciate ligament (ACL) injury especially in revision cases is return to sports activity by regaining dynamic postural stability. Among various methods to achieve this goal, additional anterolateral ligament reconstruction (ALLR) is gaining attention. The purpose of this study was to evaluate the effects of additional ALLR in revision ACL reconstruction (RACLR). Materials and Methods: Patients who underwent RACLR between July 2015 and June 2018 were enrolled. The exclusion criteria were less than 1-year follow-up, age older than 45 years, concomitant multiple ligament injuries, contralateral knee injury, subtotal or total meniscectomized state, and articular cartilage lesions worse than Outerbridge grade 3. Thirty-nine patients (20 patients; RACLR only (Group A), 19 patients; RACLR with additional ALLR (Group B)) were included. Clinical scores (Lysholm score, subjective International Knee Documentation Committee (IKDC) score, Tegner activity scale), isokinetic strength test, single-leg-hop for distance test (SLHDT), Y-balance test (YBT) were checked preoperatively and 1-year postoperatively. Results: Limb symmetry index values in YBT showed significantly better result in Group B 1-year postoperatively (Group A: 97.2 ± 4.0, Group B: 100.3 ± 2.9, p = 0.010), although there were no differences preoperatively between groups (Group A: 90.4 ± 6.7, Group B: 89.3 ± 5.5, p = 0.594). Regarding clinical scores, isokinetic strength tests, and SLHDT, there were no differences between groups preoperatively nor 1-year postoperatively. Conclusions: Additional ALLR in RACLR helped patients gain better dynamic postural stability at 1-year postoperative follow-up.

Clinical outcomes and return to sport after single-stage revision anterior cruciate ligament reconstruction by bone-patellar tendon autograft combined with lateral extra-articular tenodesis

PURPOSE

The anterior cruciate ligament reconstruction (ACLR) failure rate continues to increase. Involvement of a young population with a desire to return to sport, explains the increased need for ACLR (revACLR) revision. The aim of this study was to evaluate clinical outcome, complications, failure rate and return to sport of a single-stage revACLR using bone patellar tendon-bone (BTBT) combined with lateral extra-articular tenodesis (LET).

MATERIAL AND METHODS

A retrospective analysis was performed on 36 patients who underwent revACLR. Knee stability was assessed by Lachman and Pivot shift test. Objective anterior laxity was determined by KT-2000 arthrometer. The IKDC subjective, Lysholm, ACL-RSI Scores, level of sport activity and Forgotten Joint Score-12 were recorded.

RESULTS

Of 36 patients, we collected data from 17 who underwent single-stage revACLR with autologous BTBT combined with LET, performed using an extra-articular MacIntosh procedure as modified by Arnold-Coker. The side-to-side difference in Lachman test and Pivot shift test significantly improved postoperatively. The subjective IKDC, Lysholm and ACL-RSI significantly improved from 71.4 ± 9.03 to 92 ± 6.9, from 58.3 ± 19.3 to 66.8 ± 27.7 and from 50.4 ± 12.2 to 68.6 ± 24.5, respectively during the post-operative follow-up. Ten patients (58.8%) returned to their desired level of sport. One patient was considered a failure because of the postoperative laxity.

CONCLUSION

Single-stage revACLR with BPTB combined with LET is a safe procedure that shows good objective and subjective outcomes, and a high rate of return to the same level of sport. Reducing rotational instability and strain on intra-articular reconstructed structures results in a low rate of complications and failure.

Single Femoral Tunnel for Anterior Cruciate Ligament Reconstruction With Bone-Patellar Tendon-Bone Graft and Lemaire's Extra-Articular Tenodesis as a Good Alternative for Combined Anterior Cruciate Ligament and Anterolateral Ligament Revision Surgeries

The literature has shown a significant decrease in failure rates when the anterior cruciate ligament (ACL) reconstruction was associated with an extra-articular reinforcement technique such as the anterolateral ligament (ALL) or the iliotibial band tenodesis (ITBT) using the modified Lemaire technique. As much as there is a progressive decrease in the failure rates of ACL reconstructions when the ALL reconstruction technique is associated, there are still and will be cases that will result in graft rupture. These cases will require more alternatives for revision, which are always challenging for the surgeon, where the lateral approaches represent complicating factors, especially because of the distortion of the lateral anatomy (by the previous approach for ALL reconstruction), previous reconstruction tunnels, and the presence of fixation materials. We present here a safe technique that offers great stability to the fixation of the graft and is easy to perform, using a single tunnel for the passage of the ACL and ITBT grafts, allowing a single fixation for both. In this way, we performed a lower-cost surgery, with a lower risk of lateral condyle fracture and tunnel confluence. This technique is indicated to be used in cases of revision after failure of combined ACL reconstruction with ALL.

Comparison of Onlay Anchor Fixation Versus Transosseous Fixation for Lateral Extra-articular Tenodesis During Revision ACL Reconstruction

Background

There is evidence on the clinical effectiveness of the Lemaire technique for lateral extra-articular tenodesis (LET) in patients undergoing revision anterior cruciate ligament reconstruction (ACLR), but the best fixation technique is unknown.

Purpose

To compare the clinical outcomes of 2 fixation techniques after revision ACLR: (1) onlay anchor fixation, which would avoid tunnel conflict and physis injury, and (2) transosseous tightening and interference screw fixation. Pain at the area of LET fixation was also assessed.

Study Design

Cohort study; Level of evidence, 3.

Methods

This was a retrospective 2-center study of patients with first-time revision ACLR and either LET with anchor fixation (aLET) with a 2.4-mm suture anchor or LET with transosseous fixation (tLET). Outcomes at minimum 12-month follow-up were assessed with the International Knee Documentation Committee score, Knee injury and Osteoarthritis Outcome Score, visual analog scale for pain at the LET fixation area, Tegner score, and anterior tibial translation (ATT). A subgroup analysis within the aLET group investigated passing the graft over or under the lateral collateral ligament (LCL).

Results

In total, 52 patients were included (26 patients in each group); the mean ± SD follow-up was 13.7 ± 3.4 months. No statistically significant differences were detected between the groups with respect to patient-reported outcome scores, clinical examination, or instrumented testing (side-to-side difference in ATT at 30° of flexion; aLET, 1.5 ± 2.5 mm; tLET, 1.6 ± 1.7 mm). Clinical failure was detected in 1 patient with aLET and none with tLET. Subgroup analysis revealed a small, nonsignificant flexion deficit in knees in which the iliotibial band strand was passed under (n = 42) or over (n = 10) the LCL. No clinically relevant tenderness was detected at the area of LET fixation in any group (aLET, 0.6 ± 1.3; tLET, 0.9 ± 1.7; over the LCL, 0.2 ± 0.6; under the LCL, 0.9 ± 1.6).

Conclusion

Onlay anchor fixation and transosseous fixation of the LET were equivalent with respect to outcome scores and instrumented ATT testing. Clinically, there were minor differences in passage of the LET graft over or under the LCL.

Good stability and mid-term subjective outcomes after repeated anterior cruciate ligament (ACL) revision surgery using allografts

PURPOSE

To evaluate the mid-term clinical outcomes of a cohort of patients who underwent multiple ACL revision reconstructions. The hypothesis was that patients with pre-existing meniscal deficiency conditions, malalignment and cartilage degeneration would have obtained lower results.

METHODS

All cases of multiple ACL revisions performed with allograft tissue at one single sport-medicine institution were extracted and patients with a minimum 2 years of follow-up were included. WOMAC, Lhysolm, IKDC, and Tegner activity level before the injury and at last follow-up was collected and laxity evaluated with KT-1000 arthrometer and KiRA triaxial accelerometer.

RESULTS

From a cohort of 241 ACL revisions, 28 patients (12%) with Repeated ACL Revision reconstructions were included. Fourteen cases (50%) were considered "Complex" due to the addition of meniscal allograft transplantation (8) or meniscal scaffold (3) or high tibial osteotomy (3). The remaining 14 cases (50%) were considered as "Isolate". The mean WOMAC score was 84.6 ± 11.4, Lysholm 81.7 ± 12.3, subjective IKDC 77.2 ± 12.1, and median Tegner score 6 (IQR 5-6) at pre-injury and at final follow-up. Statistically significant inferior values of WOMAC (p = 0.008), Lysholm (p = 0.02) and Subjective IKDC (p = 0.0193) were detected between "Complex" and "Isolate" revision groups. Higher average values of anterior translation at KT-1000 at both 125 N (p = 0.03) and manual maximum displacement test (p = 0.03) were reported in "Complex" with respect to "Isolate" revisions. Four patients were considered as failures and occurred in patients with "Complex" revisions, none occurred in the "Isolate" (30% vs 0%; p = 0.04).

CONCLUSION

Good mid-term clinical results can be obtained after repeated ACL revision with allograft in patients who experienced multiple failures; however, those who need additional procedure due to malalignment or post-meniscectomy syndrome reported lower objective and subjective results.

LEVEL OF EVIDENCE

III.

Multiclass Support Vector Machine improves the Pivot-shift grading from Gerdy's acceleration resultant prior to the acute Anterior Cruciate Ligament surgery

INTRODUCTION

Rotatory laxity acceleration still lacks objective classification due to interval grading superposition, resulting in a biased pivot shift grading prior to the Anterior Cruciate Ligament (ACL) reconstruction. However, data analysis might help improve data grading in the operative room. Therefore, we described the improvement of the pivot-shift categorization in Gerdy's acceleration under anesthesia prior to ACL surgery using a support vector machine (SVM) classification, surgeon, and literature reference.

METHODS

Seventy-five patients (aged 30.3 ± 10.2 years, and IKDC 52.0 ± 16.5 points) with acute ACL rupture under anesthesia prior to ACL surgery were analyzed. Patients were graded with pivot-shift sign glide (+), clunk (++), and (+++) gross by senior orthopedic surgeons. At the same time, the tri-axial tibial plateau acceleration was measured. Categorical data were statistically described, and the accelerometry and categorical data were associated (α = 5%). A multiclass SVM kernel with the best accuracy trained by orthopedic surgeons and assisted from literature for missing data was compared with experienced surgeons and literature interval grading. The cubic SVM classifier achieved the best grading.

RESULTS

The intra-group proportions were different for each grading in the three compared strategies (p < 0.001). The inter-group proportions were different for all comparisons (p < 0.001). There were significant (p < 0.001) associations (Tau: 0.69, -0.28, and -0.50) between the surgeon and SVM, the surgeon and interval grading, and the interval and SVM, respectively.

CONCLUSION

The multiclass SVM classifier improves the acceleration categorization of the (+), (++), and (+++) pivot shift sign prior to the ACL surgery in agreement with surgeon criteria.

The Addition of Either an Anterolateral Ligament Reconstruction or an Iliotibial Band Tenodesis Is Associated With a Lower Failure Rate After Revision Anterior Cruciate Ligament Reconstruction: A Retrospective Comparative Trial

PURPOSE

To compare the failure rate in patients who underwent revision anterior cruciate ligament (ACL) reconstruction alone or associated with an extra-articular procedure. Secondary objectives were to compare ACL laxity, patient-reported outcome measures, and complication rates in these patients and, subsequently, to compare the outcomes of patients who underwent revision ACL reconstruction associated with anatomical anterolateral ligament (ALL) reconstruction or lateral extra-articular tenodesis (LET).

METHODS

This was a retrospective comparative study. Patients were classified into 2 groups, according to whether (group 2) or not (group 1) an extra-articular reconstruction was performed. Patients who underwent an extra-articular procedure were further divided into ALL reconstruction (group 2A) and LET (group 2B). Baseline demographic variables, operative data and postoperative data were evaluated.

RESULTS

The groups with (86 patients) and without (88 patients) an associated extra-articular reconstruction had similar preoperative data. Group 2 had a lower failure rate (4.6% vs 14.7%; P = .038), better KT-1000, better pivot-shift, and better Lysholm. There was no difference regarding complications, except more lateral pain in group 2. Regarding the groups who underwent ALL reconstruction (41 patients) and LET (46 patients), group 2A showed better Lysholm scores. Both groups had similar failure rates and complications.

CONCLUSIONS

Patients who underwent revision ACL reconstruction with a laterally based augmentation procedure had a lower failure rate than patients who underwent isolated revision ACL reconstruction. KT-1000 and pivot-shift examination were also significantly better when a lateral augmentation was performed. Complications were similar except for an increase in lateral pain in the augmented group. No clinically important differences were found when comparing the LET group to the ALL group other than a statistical improvement in the Lysholm functional scale, likely not clinically meaningful, favoring the ALL group and an increased duration of post-operative lateral pain in the LET group.

LEVEL OF EVIDENCE

III, retrospective comparative therapeutic trial.

Allografts and lateral extra-articular tenodesis for revision anterior cruciate ligament reconstruction: enhanced rotational stability and improved functional outcomes

PURPOSE

Multiple studies have shown higher failure rate and patient-reported outcomes to be significantly worse following revision anterior cruciate ligament reconstructive (ACLR) surgery, especially using allografts. One of the reasons being rotational instability. Because of this, augmentation with lateral extra-articular tenodesis (LET) is often considered. Good short-term results in regards to functional and perceived scores and low complication rate can be expected in revision ACLR using allografts in combination with LET.

METHODS

Between 2014 and 2021, 46 patients were registered for revision ACLR using allografts and extra-articular augmentation (modified Lemaire) and included in this prospective study. Patients' demographic and clinical data were collected preoperatively, postoperatively, and during the follow-up period of 12 months.

RESULTS

Patient-reported functional outcomes were statistically significant for IKDC, Lysholm, and SF-12 physical scale (p < 0.05). Tegner score showed a decreased number of patients who were able to return to sport at their previous level (p = 0.001). Stability examination tests (Lachman and pivot-shift) showed significant improvements. Concomitant lesions were present in 76.1% of patients. Ten patients (21.7%) presented major complications, including six cases of anteroposterior instability, three cases of knee pain and one graft re-rupture.

CONCLUSION

Revision procedures are inherently challenging with a high number of associated chondral and meniscus lesions. However, good short-term functional outcomes and enhanced rotational stability with an acceptable complication rate can be expected in most cases where revision ACLR using allografts is augmented with LET.

STUDY DESIGN

Prospective; Case series; Level of evidence IV.

Combined Anterior Cruciate Ligament and Anterolateral Ligament Reconstruction Results in Superior Rotational Stability Compared with Isolated Anterior Cruciate Ligament Reconstruction in High Grade Pivoting Sport Patients: A Prospective Randomized Clinical Trial

The purpose of the current randomized clinical trial (RCT) was to evaluate the clinical outcomes of combined anterior cruciate ligament (ACL) and anterolateral ligament (ALL) reconstruction and to compare them with those of isolated ACL reconstruction. The hypothesis was that combined ACL and ALL reconstruction will result in superior clinical outcomes in terms of the rotational stability of the knee. This prospective RCT included 57 patients (44 men and 13 women, mean age = 31 ± 7.1 years) who underwent ACL reconstruction either isolated (Group I: 25 patients) or combined with ALL reconstruction (Group II: 32 patients). The evaluation of the patients was done preoperatively and postoperatively at 6 weeks, 12 weeks, 6 months, and 12 months including a clinical examination (Lachman's test, Pivot shift's test, and Rolimeter differential anterior laxity), an objective clinical scores (objective: the International Knee Documentation Committee [IKDC] score) and a subjective clinical scores (subjective: IKDC's score, Lysholm's score, and Tegner's activity score). Postoperative complications of all the patients were recorded. There was a significant difference between the study groups at all follow-up intervals when evaluating the postoperative pivot shift test (p < 0.05) with a superior rotational stability in the group of combined ACL and ALL reconstruction. At the final follow-up evaluation, 36% of the patients from Group I and 6.2% in Group II had a grade I positive pivot shift test (p < 0.05). There was a statistically significant difference between the two groups regarding the number of patients with a grade A IKDC objective score (p < 0.05) at the 6- and 12-month follow-up intervals (p = 0.007). There was a significant difference concerning the IKDC subjective score between the two study groups in favor of the combined ACL and ALL reconstruction group at 12 months postoperatively (p = 0.048). Combined ACL and ALL reconstruction technique was demonstrated to be effective in obtaining a superior control of the rotational knee instability and to improve the clinical objective and subjective outcomes when compared with isolated ACL reconstruction in sports patients with high-grade pivoting shifts.

Anterior cruciate ligament arthroscopic reconstruction and lateral tenodesis with iliotibial band and gracilis tendon: Technical note

While anterior cruciate ligament reconstruction using the iliotibial band is not a new technique, it still remains underdeveloped. The iliotibial band has historically been described as a thin and less resistant structure. Its harvesting has been associated with a risk of complications (hematoma, muscle hernia) and its small graft diameter increases the risk of rerupture. The addition of the gracilis tendon could potentially produce a graft with an increased diameter. In this technical note, we present a modification to the traditional technique performed on 50 patients, describing the surgical steps, graft diameter, clinical outcomes and complications at the 2-year follow-up. The mean graft diameter was 8.9±0.9 mm at the femur and 7.7±0.7 mm at the tibia. No rerupture was reported at the 2-year follow-up. LEVEL OF EVIDENCE: IV.

Effect of Lateral Extra-articular Tenodesis on the Rate of Revision Anterior Cruciate Ligament Reconstruction in Elite Athletes

BACKGROUND

There is growing evidence that anterolateral procedures can reduce the risk of rerupture in high-risk recreational athletes undergoing primary anterior cruciate ligament (ACL) reconstruction (ACLR). However, this effectiveness has never been evaluated in elite athletes.

PURPOSE

The purpose of this study was to evaluate the effectiveness of lateral extra-articular tenodesis (LET) in reducing revision rates in primary ACLR in elite athletes. Additionally, this study evaluated whether LET had a greater effect when combined with ACLR utilizing a hamstring or patellar tendon graft.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A consecutive cohort of elite athletes with an isolated ACL tear undergoing autograft patellar or hamstring tendon reconstruction with or without Lemaire LET were analyzed between 2005 and 2018. A minimum 2-year follow-up was required. The association between the use of LET and ACL graft failure as defined by revision ACLR was evaluated with univariate and multivariate logistic regression models.

RESULTS

A total of 455 elite athletes (83% men and overall age 22.5 ± 4.7 years) underwent primary ACLR with (n = 117) or without (n = 338) a LET procedure. Overall, 36 athletes (7.9%) experienced ACL graft failure, including 32 (9.5%) reconstructions without a LET and 4 (3.4%) with a LET. Utilization of LET during primary ACLR reduced the risk of graft failure by 2.8 times, with 16.5 athletes needing LET to prevent a single ACL graft failure. Multivariate models showed that LET significantly reduced the risk of graft rupture (relative risk = 0.325; P = .029) as compared with ACLR alone after controlling for sex and age at ACLR. Including graft type in the model did not significantly change the risk profile, and although a patellar tendon graft had a slightly lower risk of failure, this was not statistically significant (P = .466).

CONCLUSION

The addition of LET reduced the risk of undergoing revision by 2.8 times in elite athletes undergoing primary ACLR. This risk reduction did not differ significantly between the patellar tendon and hamstring tendon autografts. With these results, status as an elite athlete should be included in the indications for a LET, as they are at increased risk for ACL graft failure.

Slope-Reducing High Tibial Osteotomy and Over-The-Top Anterior Cruciate Ligament Reconstruction With Achilles Tendon Allograft in Multiple Failed Anterior Cruciate Ligament Reconstruction

Graft failure is a challenging complication following anterior cruciate ligament reconstruction (ACL-R). Among the multiple anatomic and nonanatomic risk factors contributing to ACL-R failure, there is accumulating evidence that a posterior tibial slope of 12° or greater may predispose patients to graft failure of primary and revision ACL-R. In addition, previously malpositioned or widened tunnels, as well as limited autograft options, pose challenges in the setting of revision ACL-R. This Technical Note describes a technique to correct an increased posterior tibial slope using slope-reducing high tibial osteotomy, and single stage revision ACL-R with Achilles tendon allograft using the over-the-top route, in a single-stage procedure. The surgical technique involves an anterior approach to the proximal tibia, followed by tibial tubercle osteotomy and anterior closing-wedge osteotomy. The posterior cortical osteotomy hinge is left intact below the insertion of the posterior cruciate ligament. Over-the-top revision ACL-R is then performed using an Achilles tendon allograft passed around the posterior aspect of the lateral femoral condyle and fixed onto the lateral femur.

Integration of polyurethane meniscus scaffold during ACL revision is not reliable at 5 years despite favourable clinical outcome

PURPOSE

The aim of this study was to evaluate the clinical outcome at 5-year follow-up of a one-step procedure combining anterior cruciate ligament (ACL) reconstruction and partial meniscus replacement using a polyurethane scaffold for the treatment of symptomatic patients with previously failed ACL reconstruction and partial medial meniscectomy. Moreover, the implanted scaffolds have been evaluated by MRI protocol in terms of morphology, volume, and signal intensity.

METHODS

Twenty patients with symptomatic knee laxity after failed ACL reconstruction and partial medial meniscectomy underwent ACL revision combined with polyurethane-based meniscal scaffold implant. Clinical assessment at 2- and 5-year follow-ups included VAS, Tegner Activity Score, International Knee Documentation Committee (IKDC), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the Lysholm Score. MRI evaluation of the scaffold was performed according to the Genovese scale with quantification of the scaffold's volume at 1- and 5-year follow-ups.

RESULTS

All scores revealed clinical improvement as compared with the preoperative values at the 2- and 5-year follow-ups. However, a slight, but significant reduction of scores was observed between 2 and 5 years. Concerning the MRI assessment, a significant reduction of the scaffold's volume was observed between 1 and 5 years. Genovese Morphology classification at 5 years included two complete resorptions (Type 3) and all the remaining patients had irregular morphology (Type 2). With regard to the Genovese Signal at the 5-year follow-up, three were classified as markedly hyperintense (Type 1), 15 as slightly hyperintense (Type 2), and two as isointense (Type 1).

CONCLUSION

Simultaneous ACL reconstruction and partial meniscus replacement using a polyurethane scaffold provides favourable clinical outcomes in the treatment of symptomatic patients with previously failed ACL reconstruction and partial medial meniscectomy at 5 years. However, MRI evaluation suggests that integration of the scaffold is not consistent.

LEVEL OF EVIDENCE

Level IV.

Over-The-Top Technique for Revision ACL Reconstruction with Achilles Allograft and Associated Lateral Extra-articular Tenodesis

Revision anterior cruciate ligament reconstruction (ACL-R) is made challenging by the frequent presence of rotatory instability, tunnel malpositioning and widening, and limited autograft options. Lateral extra-articular tenodesis (LET), alternative tunnel routing, and the use of allograft tissue can be used to manage these challenges. This Technical Note describes revision ACL-R using the over-the-top (OTT) technique with Achilles tendon allograft with concomitant LET. The surgical approach involves routing the graft around the posterior aspect of the lateral femoral condyle, and then deep to the iliotibial band to a site just medial to Gerdy's tubercle, with staple fixation on the lateral femur for the ACL-R and anterolateral tibia for the LET. The OTT technique with LET provides a versatile approach for the management of failed ACL-R by circumventing challenges in revision ACL-R and addressing rotatory instability, a contributing factor to prior graft failure.

Anterolateral Structure Reconstructions With Different Tibial Attachment Sites Similarly Improve Tibiofemoral Kinematics and Result in Different Graft Force in Treating Knee Anterolateral Instability

PURPOSE

To compare the biomechanical effects of anterolateral structure reconstructions (ALSRs) with different tibial attachments on tibiofemoral kinematics and anterolateral structure (ALS) graft forces.

METHODS

Eight cadaveric knees were tested in a customized knee testing system, using a novel pulley system to simulate more muscle tensions by loading the iliotibial band at 30 N and quadriceps at 10 N in all testing states. Anterior stability during anterior load and anterolateral rotatory stability during 2 simulated pivot-shift tests (PST1 and PST2) were evaluated in 5 states: intact, ALS-deficient (Def), ALSR-Ta (anterior tibial site), ALSR-Tm (middle tibial site), and ALSR-Tp (posterior tibial site). Tibiofemoral kinematics and resulting ALS graft forces against the applied loads were measured and compared in the corresponding states.

RESULTS

In anterior load, 3 ALSRs mitigated the anterior laxities of the ALS Def state at all degrees, which were close to intact state at 0° and 30° but showed significantly overconstraints at 60° and 90°. In both PSTs, all ALSRs significantly reduced the anterolateral rotatory instability of ALS Def, whereas the significant overconstraints were detected in ALSR-Ta and ALSR-Tm at greater knee flexion angles. All ALS grafts carried forces in resisting anterior and pivot-shift loads. Only ALS graft force in ALSR-Ta increased continuously with knee flexion angles. The ALS graft forces carried by ALSR-Ta were significantly larger than those by ALSR-Tp and ALSR-Tm when resisting anterior load and PSTs at greater knee flexion angles.

CONCLUSIONS

ALSRs with different tibial attachment sites similarly restored knee laxities close to the native tibiofemoral kinematics in an ALS-deficient knee, whereas the ALSR-Tp showed less propensity for overconstraining the knee at greater flexion angles. The ALS graft in ALSR-Ta carried more forces than those in ALSR-Tp and ALSR-Tm against simulated loads.

CLINICAL RELEVANCE

Altering the tibial attachment sites of ALSRs may not significantly affect tibiofemoral kinematics at most degrees whereas the posterior may have less overconstraints at greater flexion angles. However, ALS graft positioning at a more anterior tibial attachment site may carry more forces in resisting anterior and pivot-shift loads.

Overview of the anterolateral complex of the knee

In the last few years, much more information on the anterolateral complex of the knee has become available. It has now been demonstrated how it works in conjunction with the anterior cruciate ligament (ACL) controlling anterolateral rotatory laxity. Biomechanical studies have shown that the anterolateral complex (ALC) has a role as a secondary stabilizer to the ACL in opposing anterior tibial translation and internal tibial rotation. It is of utmost importance that surgeons comprehend the intricate anatomy of the entire anterolateral aspect of the knee. Although most studies have only focused on the anterolateral ligament (ALL), the ALC of the knee consists of a functional unit formed by the layers of the iliotibial band combined with the anterolateral joint capsule. Considerable interest has also been given to imaging evaluation using magnetic resonance and several studies have targeted the evaluation of the ALC in the setting of ACL injury. Results are inconsistent with a lack of association between magnetic resonance imaging evidence of injury and clinical findings. Isolated ACL reconstruction may not always reestablish knee rotatory stability in patients with associated ALC injury. In such cases, additional procedures, such as anterolateral reconstruction or lateral tenodesis, may be indicated. There are several techniques available for ALL reconstruction. Graft options include the iliotibial band, gracilis or semitendinosus tendon autograft, or allograft.

3D Killer Turn Angle in Transtibial Posterior Cruciate Ligament Reconstruction Is Determined by the Graft Turning Angle both in the Sagittal and Coronal Planes

Objective

During the transtibial posterior cruciate ligament (PCL) reconstruction, surgeons commonly pay more attention to the graft turning angle in the sagittal plane (GASP), but the graft turning angle in the coronal plane (GACP) is always neglected. This study hypothesized that the three‐dimensional (3D) killer turn angle was determined by both the GASP and GACP, and aimed to quantitively analyze the effects of the GASP and GACP on the 3D killer turn angle.

Methods

This was an in‐vitro computer simulation study of transtibial PCL reconstruction using 3D knee models. Patients with knee injuries who were CT scanned were selected from the CT database (April 2019 to January 2021) at a local hospital for reviewing. A total of 60 3D knees were simulated based on the knees' CT data. The femoral and tibial PCL attachment were located on the 3D knee model using the Rhinoceros software. The tibial tunnels were simulated based on different GASP and GACP. The effects of the GASP and GACP on the 3D killer turn angle were quantitatively analyzed. One‐way analysis of variance was used to compare the outcomes in different groups. The regression analysis was performed to identify variables of the GASP and GACP which significantly affected 3D killer turn angle.

Results

The 3D killer turn angle showed a significant proportional relationship not only with the GASP (r² > 0.868, P < 0.001), but also with the GACP (r² > 0.467, P < 0.001). Every 10° change of the GACP caused 2.8° to 4.4° change of the 3D killer turn angle, whereas every 10° change of the GASP caused 6.4° to 9.2° change of the 3D killer turn angle.

Conclusions

The 3D killer turn angle was significantly affected by both the GASP and GACP. During the transtibial PCL reconstruction, the proximal anterolateral tibial tunnel approach could increase the 3D killer turn angle more obviously compared with the most distal anteromedial tibial tunnel approach. To minimize the killer turn effect, both the GASP and GACP were required to be considered to increase.

Imaging Findings of Complications After Lateral Extra-Articular Tenodesis of the Knee: A Current Concepts Review

Background:

Despite successful anterior cruciate ligament (ACL) reconstruction, many patients continue to experience persistent anterolateral rotatory instability. Lateral extra-articular tenodesis (LET) is used to address this instability by harvesting a portion of the iliotibial band, passing it underneath the fibular collateral ligament, and attaching it just proximal and posterior to the lateral femoral epicondyle. Based on the most recent clinical evidence, the addition of LET to ACL reconstruction improves clinical outcomes, which has led to an increase in the use of this technique.

Purpose:

To provide an overview of the postoperative complications of the LET procedure and their associated imaging findings, with a focus on magnetic resonance imaging (MRI).

Study Design:

Narrative review.

Methods:

In this scoping review, the authors reviewed available radiographic, computed tomography, and MRI scans of patients who experienced postoperative complications after ACL reconstruction with LET, in which the complication was determined to be from the LET procedure. Images were reviewed and subsequently described by an on-staff musculoskeletal radiologist.

Results:

The authors found 9 different complications associated with LET: graft failure, hematoma, infection, chronic pain, tunnel convergence, fixation device migration, muscular hernia, peroneal nerve palsy, and knee stiffness. They supplemented these findings with radiographic evidence from 6 patients.

Conclusion:

As extra-articular reconstruction techniques including LET become more popular among orthopaedic surgeons, it is important that radiologists and surgeons be adept at recognizing the normal imaging findings of LET and associated complications.

Controversies in ACL revision surgery: Italian expert group consensus and state of the art

Background

Revision ACL reconstruction is a complex topic with many controversies and not-easy-to-make decisions. The authors’ aim is to provide some feasible advice that can be applied in daily clinical practice with the goal of facilitating the decision-making process and improving the outcomes of patients subjected to revision ACL reconstruction.

Methods

A national survey with seven questions about the most controversial topics in revision ACL reconstruction was emailed to members of two societies: SIOT and SIAGASCOT. The participants’ answers were collected, the most recent literature was analyzed, and a consensus was created by the authors, according to their long-term surgical experience.

Conclusions

The decision-making process in revision ACL reconstruction starts with a standardized imaging protocol (weight-bearing radiographs, CT scan, and MRI). One-stage surgery is indicated in almost all cases (exceptions are severe tunnel enlargement and infection), while the choice of graft depends on the previously used graft and the dimensions of the tunnels, with better clinical outcomes obtained for autografts. Additional procedures such as lateral extra-articular tenodesis in high-grade pivot-shift knees, biplanar HTO in the case of severe coronal malalignment, and meniscal suture improve the clinical outcome and should be considered case by case.

Level of evidence

V (Expert opinion).

How to Avoid Knee Tunnel Convergence When Performing a Modified Lemaire Extra-Articular Tenodesis

There has been a significant increase in the number of anterior cruciate ligament (ACL) reconstruction (ACLR) procedures being performed with a lateral extra-articular procedure (LEAP). However, tunnel convergence in combined ACLR and LEAP techniques has been described and can lead to damage to the graft or graft failure. This technical note describes how to avoid knee tunnel convergence when performing a modified Lemaire extra-articular tenodesis using a knotless suture anchor.

Combined Revision Anterior Cruciate Ligament and Anterolateral Ligament Reconstruction

There has been a substantial increase in the number of revision anterior cruciate ligament (ACL) reconstructions performed in the past decade. This Technical Note describes combined revision ACL and anterolateral ligament reconstruction using outside-in drilling, which avoids the need for 2-stage revision ACL reconstruction because it allows unconstrained anatomic placement.

Risk of Graft Rupture After Adding a Lateral Extra-articular Procedure at the Time of ACL Reconstruction: A Retrospective Comparative Study of Elite Alpine Skiers From the French National Team

BACKGROUND

Elite alpine skiing is associated with a particularly high risk of anterior cruciate ligament (ACL) injuries, including graft ruptures. Despite a considerable focus on prevention, a reduction in injury rates has not been observed since the 1980s.

PURPOSE

To determine whether elite alpine skiers undergoing ACL reconstruction (ACLR) with a lateral extra-articular procedure (LEAP) had a lower rate of ACL graft rupture when compared with those who underwent isolated ACLR.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Elite skiers from the French ski team who had undergone ACLR, with or without a LEAP, and had a minimum follow-up of 2 years were identified from the national ski team database. Rates of secondary ACL injury were determined via interrogation of the database, review of medical notes, and a final telemedicine interview. A multivariable analysis using the penalized Cox model was performed to explore the relationship among graft rupture, surgical procedure type, and any potential explanatory variables.

RESULTS

Among 81 ACLR procedures analyzed, 50 were isolated and 31 were combined with a LEAP, which was performed using modified Lemaire or anterolateral ligament reconstruction. Graft rupture rates were 34.0% in the isolated ACLR group and 6.5% in the ACLR + LEAP group. Multivariable analysis demonstrated that adding a LEAP was associated with a significant reduction in risk of ACL graft rupture when compared with isolated ACLR (hazard ratio [HR], 5.286 [95% CI, 1.068-26.149]; P = .0412). Age (HR, 1.114; P = .1157), sex (HR, 1.573; P = .3743), and ACL graft type (HR, 1.417; P = .5394) were not significant risk factors.

CONCLUSION

Combined ACLR and LEAP were associated with a significant reduction in the rate of ACL graft rupture in elite alpine ski athletes. Those treated with isolated ACLR remain at extremely high risk of a second ACL injury.

Revision ACL reconstruction has higher incidence of 30-day hospital readmission, reoperation, and surgical complications relative to primary procedures

PURPOSE

Although there has been substantial improvement in ACL reconstructive surgery, graft failure remains a devastating complication for some patients. Revision procedures are inherently more complex and technically challenging. The purpose of this study is to determine the incidence of short-term complications after these procedures and to compare trends in operative length, relative valuation, and reimbursement after primary versus revision ACL reconstruction.

METHODS

Primary and revision arthroscopic ACL reconstruction cases were identified on the American College of Surgeons' NSQIP database using Current Procedural Terminology (CPT) and International Classification of Diseases (ICD) codes between January 1, 2012 and December 31, 2017. Demographics, patient variables, and surgical variables were compared between primary and revision groups using Chi-squared tests. Logistic regression was used to identify independent risk factors for revision ACL reconstruction. Various 30-day outcome measures were compared between the primary and revision ACL reconstruction groups. Various measures of valuation-including total relative value units (RVU) and reimbursement per minute-were calculated and compared between the two groups.

RESULTS

A total of 8292 patients-8135 primary and 157 revision procedures-were included in the final cohort. Higher ASA scores were associated with revision ACL reconstructions. Patients undergoing revision procedures were less likely to have an ASA score of 1 (p < 0.001) and more likely to have an ASA score of 2 (p = 0.004) or 3 (p = 0.020). Revision ACL reconstruction was associated with higher rates of poor 30-day outcome measures, including unplanned readmission (p = 0.029), reoperation (p = 0.012), return to the OR (p = 0.012), and surgical complications (p = 0.021). The total RVUs and reimbursement for revision procedures were significantly greater than those for primary procedures (p < 0.001). However, when accounting for operative time, the RVU/minute and reimbursement/minute were similar between the two groups (n.s.).

CONCLUSIONS

Relative to primary ACL reconstruction, revision ACL procedures are associated with worse short-term outcomes-including unplanned readmission, reoperation, return to the OR, and surgical complications. A greater ASA score was independently predictive of revision ACL surgery. The current RVU system undervalues revision ACL procedures, considering the increased operative time and complexity of such procedures.

LEVEL OF EVIDENCE

Level III.

The Permissive Safe Angle of the Tibial Tunnel in Transtibial Posterior Cruciate Ligament Reconstruction: A Three-Dimensional Simulation Study

Objective

To determine the permissive safe angle (PSA) of the tibial tunnel in transtibial posterior cruciate ligament (PCL) reconstruction based on a three‐dimensional (3D) simulation study.

Methods

This was a computer simulation study of transtibial PCL reconstruction using 3D knee models. CT images of 90 normal knee joints from 2017 to 2020 were collected in this study, and 3D knee models were established based on CT data. The tunnel approaches were subdivided into the anterior 1/3 of the anteromedial tibia (T1), middle 1/2 of the anteromedial tibia (T2), the tibial crest (T3), anterior 1/3 of the anterolateral tibia (T4), middle 1/2 of the anterolateral tibia (T5). Five tibial tunnels (T1–T5) were simulated on the 3D knee models. The PSAs, in different tibial tunnel approaches were measured, and subgroup analyses of sex, age and height were also carried out.

Results

The mean PSAs of the tibial tunnels with 5 different approaches (T1–T5) were 58.49° ± 6.82°, 61.14° ± 6.69°, 56.12° ± 7.53°, 52.01° ± 8.89° and 49.90° ± 10.53°, respectively. The differences of the mean PSAs between the anteromedial and anterolateral approaches were significant (P < 0.05). However, there was no significant difference of the mean PSA value between the two anteromedial tibial tunnel approaches (T1–T2) (P > 0.05), as well as between the two anterolateral tibial tunnel approaches (T4–T5). The patient's anthropomorphic characteristics of sex, age, and height were not associated with the PSAs.

Conclusions

The PSA varied with the anteromedial, tibial crest and anterolateral approaches for transtibial PCL reconstruction, and surgeons should limit the PCL drill guide by referring to the specific PSA for different surgical approaches.

Revision Anterior Cruciate Ligament Reconstruction Using Bone-Patellar Tendon-Bone Graft Combined With Modified Lemaire Technique Versus Hamstring Graft Combined With Anterolateral Ligament Reconstruction: A Clinical Comparative Matched Study With a Mean Follow-up of 5 Years From The SANTI Study Group

BACKGROUND

Additional lateral extra-articular tenodesis (LET) has recently been correlated with improved clinical outcomes and reduced failure rates in revision anterior cruciate ligament (ACL) reconstruction (ACLR). However, no data are available on clinical outcomes and reoperation after revision ACLR using different LET procedures.

PURPOSE

To compare the clinical outcomes of ACL + anterolateral ligament (ALL) reconstruction using hamstring tendon graft (HT-ALL) and a bone-patellar tendon-bone (BPTB) graft + modified Lemaire tenodesis procedure (BPTB-Lemaire) in the setting of revision ACLR and to determine whether ALL reconstruction is associated with an increased rate of adverse outcomes when compared with a modified Lemaire tenodesis procedure.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Descriptive data and clinical outcomes were prospectively collected from patients who underwent revision ACLR with LET between 2009 and 2018 with a minimum follow-up of 2 years. Patients with an HT autograft combined with ALL reconstruction (HT-ALL group) were matched in a 1:1 propensity ratio to patients with a BPTB autograft combined with a modified Lemaire LET procedure (BPTB-Lemaire group). The evaluated parameters included complications and reoperations; knee laxity tests; return to sports; and various scores, including the Lysholm knee score, Tegner activity scale, Anterior Cruciate Ligament Return to Sport After Injury scale, Marx activity rating scale, International Knee Documentation Committee subjective knee evaluation form, and Knee injury and Osteoarthritis Outcome Score.

RESULTS

In total, 36 matched pairs were included in the analysis. The mean follow-up durations for the BPTB-Lemaire and HT-ALL groups were 56 ± 35 and 57 ± 23 months, respectively (P = .91). No significant differences were found in graft rupture rate (HT-ALL, 0%; BPTB-Lemaire, 11.1%; P = .13) or reoperations (HT-ALL, 8.3%; BPTB-Lemaire, 22.2%; P = .23). No specific complications with regard to LET were noted in either group. Additionally, there were no significant differences in knee laxity parameters, return to sports, or clinical scores between the groups at the final follow-up, except for the Tegner activity scale score (HT-ALL, 6.4; BPTB-Lemaire, 7.3; P = .03). HT-ALL was associated with a shorter surgical time (41.4 vs 59.8 minutes; P < .0001).

CONCLUSION

HT-ALL was at least equivalent, in terms of clinical outcomes, to the more commonly performed procedure, BPTB-Lemaire. Performing ALL reconstruction in the setting of revision ACLR is therefore safe and effective.

Resultado funcional do procedimento de tenodese extra-articular lateral (TEL) como complemento à reconstrução do ligamento cruzado anterior: Uma metanálise

Objectives  The aim of the present study is to systematically review and analyze the functional outcome of lateral extraarticular tenodesis (LET) procedure in addition to anterior cruciate ligament reconstruction (ACLR) in studies with a high level of evidence.

Methods  We performed a literature search for clinical studies comparing the LET method as an augmentation to ACL reconstruction with ACL reconstruction alone. The primary outcomes were the International Knee Documentation Committee (IKDC) score, the Lysholm score, and graft failures. Continuous variables were reported as means and 95% confidence intervals (CIs).

Results  Six clinical studies with 1,049 patients were included in the metaanalysis. The follow-up period was, in average, 24 months (range, 6–63 months). The addition of the LET procedure to ACLR results in better functional outcome based on the IKDC score ( p  < 0.05). Graft failure was found to be lower in the ACLR plus LET group (16 of 342 patients) compared with the ACLR-only group (46 of 341 patients) ( p  < 0.05).

Conclusion  There is high-level evidence that LET procedure in addition to ACLR is preferable in terms of functional outcome and graft failure.

Quadriceps tendon autograft is becoming increasingly popular in revision ACL reconstruction

PURPOSE

To evaluate trends in revision anterior cruciate ligament reconstruction (ACL-R), with emphasis on intra-articular findings, grafts, and concurrent procedures. It was hypothesized that revision ACL-Rs over time show a trend toward increased complexity with increased use of autografts over allografts.

METHODS

This was a two-center retrospective study including patients undergoing revision ACL-R between 2010 and 2020. Demographic and surgical data including intra-articular findings and concurrent procedures were collected and compared for the time periods 2010-2014 and 2015-2020. All collected variables were compared between three pre-defined age groups (< 20 years, 20-30 years, > 30 years), right and left knees, and males and females. A time series analysis was performed to assess trends in revision ACL-R.

RESULTS

This study included 260 patients with a mean age of 26.2 ± 9.4 years at the time of the most recent revision ACL-R, representing the first, second, third, and fourth revision ACL-R for 214 (82%), 35 (14%), 10 (4%), and 1 (< 1%) patients, respectively. Patients age > 30 years showed a significantly longer mean time from primary ACL-R to most recent revision ACL-R (11.1 years), compared to patients age < 20 years (2.2 years, p < 0.001) and age 20-30 years (5.5 years, p < 0.05). Quadriceps tendon autograft was used significantly more often in 2015-2020 compared to 2010-2014 (49% vs. 18%, p < 0.001). A high rate of concurrently performed procedures including meniscal repairs (45%), lateral extra-articular tenodesis (LET; 31%), osteotomies (13%), and meniscal allograft transplantations (11%) was shown. Concurrent LET was associated with intact cartilage and severely abnormal preoperative knee laxity and showed a statistically significant and linear increase over time (p < 0.05). Intact cartilage (41%, p < 0.05), concurrent medial meniscal repairs (39%, p < 0.05), and LET (35%, non-significant) were most frequently observed in patients aged < 20 years.

CONCLUSION

Quadriceps tendon autograft and concurrent LET are becoming increasingly popular in revision ACL-R. Intact cartilage and severely abnormal preoperative knee laxity represent indications for LET in revision ACL-R. The high rate of concurrent procedures observed demonstrates the high surgical demands of revision ACL-R.

LEVEL OF EVIDENCE

Level III.

Additional lateral extra-articular tenodesis in revision ACL reconstruction does not influence the outcome of patients with low-grade anterior knee laxity

INTRODUCTION

There is limited evidence on the indications of lateral extra-articular tenodesis (LET) in revision ACLR. The aim of this study was to evaluate the influence of the LET in patients with revision ACLR with preoperative low-grade anterior knee laxity.

METHODS

Between 2013 and 2018, 78 patients who underwent revision ACLR with preoperative low-grade anterior knee laxity [≤ 5 mm side-to-side difference (SSD)] were included in the retrospective cohort study. An additional modified Lemaire tenodesis was performed in 23 patients during revision ACLR and patients were clinically examined with a minimum of 2 years after revision surgery. Postoperative failure of the revision ACLR was defined as SSD in Rolimeter^® testing ≥ 5 mm or pivot-shift grade 2/3.

RESULTS

In total, failure of the revision ACLR occurred in 11.5% (n = 9) of the cases at a mean follow-up of 28.7 ± 8.8 (24-67) months. Patients with an additional LET and revision ACLR did not show a significantly reduced failure rate (13% vs. 11%) or an improved clinical outcome according to the postoperative functional scores or pain in regards to patients with an isolated revision ACLR (Tegner 5.7 ± 1.3 vs. 5.9 ± 1.5, n.s.; IKDC 77.5 ± 16.2 vs. 80.1 ± 14.9, n.s., Lysholm 81.9 ± 14.2 vs. 83.8 ± 14.5, n.s.; VAS 1.9 ± 2.2 vs. 1.2 ± 1.7, n.s.).

CONCLUSIONS

An additional LET in patients with revision ACLR with low-grade anterior knee laxity does not influence patient-related outcomes or failure rates. Subjects with preoperative low-grade anterior knee laxity may not benefit from a LET in revision ACLR.

LEVEL OF EVIDENCE

III.

Clinical outcomes of rectangular tunnel technique in posterior cruciate ligament reconstruction were comparable to the results of conventional round tunnel technique

PURPOSE

To compare clinical outcomes between the conventional round and rectangular tunnel techniques in single-bundle posterior cruciate ligament (PCL) reconstruction.

METHODS

Twenty-seven and 108 patients who underwent PCL reconstructions using a rectangular dilator (Group 1) and rounded tunnel reamer (Group 2), respectively, were included. The exclusion criteria were having a concomitant fracture, osteotomy, subtotal or total meniscectomy, and no remnant PCL tissue. A 4:1 propensity score matching was performed. The knee laxity on stress radiography, International Knee Documentation Committee Subjective Knee Evaluation score, Tegner activity score and Orthopädische Arbeitsgruppe Knie score were evaluated.

RESULTS

No significant differences were found between the groups in terms of clinical scores. (n.s.) The mean posterior translations were also not significantly different between the Group 1 and 2 (3.6 ± 2.8 and 3.8. ± 3.1 mm, respectively; n.s.). However, 3 patients (11.1%) in Group 1 and 15 patients (13.8%) in Group 2 showed posterior translation of > 5 mm. The combined posterolateral corner sling technique was performed for 27 patients (100%) in Group 1 and for 96 patients (88.9%) in Group 2. We found no significant difference in rotational stability at the final follow-up. One patient was found to have a femoral condyle fracture during rectangular femoral tunnel establishment, which was healed after screw fixation, without laxity, during follow-up. The intra- and inter-observer reliabilities of the radiological measurements ranged from 0.81 to 0.89.

CONCLUSION

Arthroscopic anatomical remnant-preserving PCL reconstruction using a rectangular dilator showed satisfactory clinical results and stability as compared with PCL reconstruction using a conventional rounded reamer. Rectangular tunnel technique in PCL reconstruction could be a good treatment option with theoretical advantage to be anatomic.

LEVEL OF EVIDENCE

Level IV.

Three-in-One Procedure for Revision ACL Reconstruction

Revision anterior cruciate ligament (ACL) reconstruction is a challenge due to the unfavorable condition of the knee and the lack of autogenous graft tissue. Anterolateral structure (ALS) reconstruction of the knee has been proved effective to address the unfavorable condition in revision cases, and lateral extra-articular tenodesis (LET) is a special technique that can enhance anterolateral stability of the knee without graft tissue. We introduce a procedure that combines ACL and ALS reconstruction, as well as LET for failed ACL reconstruction. The critical point of this technique is using the anterior half of the iliotibial band to realize LET and to partially reconstruct the ACL. Our clinical experience indicates this technique is extremely useful in revision ACL reconstruction without enough free graft tissue. This technique will provide a reasonable choice in revision ACL reconstruction.

Editorial Commentary: Revision Anterior Cruciate Ligament Using Soft Tissue Autograft Quadriceps Is Effective but Not Recommended for All Comers

The average revision rate is between 3.2% and 11.1%following primary anterior cruciate ligament (ACL) reconstructions,¹ and an objective failure rate of 13.7% has been reported for revision ACLR.² Prior implants, positioning of tunnels, and muscle weakness from the prior reconstruction present challenges. Additionally, graft choice for the revision reconstruction is restricted, depending on the primary reconstruction. Revision ACL reconstruction with the all-soft tissue quadriceps tendon autograft is a viable option with 83.3% of the patients surpassing the minimally clinically significant difference for International Knee Documentation Committee (IKDC) scores, which is similar to outcomes for revision ACL reconstruction (ACLR) using bone-patella-bone and hamstring tendon autografts. Furthermore, objective strength data suggest that it is possible to achieve equal limb symmetry index strength ratios even in the setting of prior bone-patella tendon-bone autograft. However, although I am cautiously optimistic regarding soft tissue quadriceps autograft in revision ACLR, I would be hesitant to recommend it for all comers. In my experience, young high school/collegiate female athletes with primary reconstruction using BPTB autograft may not be able to tolerate a secondary insult to the extensor mechanism via quadriceps tendon (QT) autograft harvest, where hematoma and arthrofibrosis could be concerns. Furthermore, increased posterior tibial slope may require evaluation and treatment, and the addition of a lateral extra-articular tenodesis may reduce residual rotatory laxity in ACL revision patients.

ACL Study Group presents the global trends in ACL reconstruction: biennial survey of the ACL Study Group

OBJECTIVES

The primary objective of this survey was to gauge the current global trends in anterior cruciate ligament reconstruction (ACLR) as reported by the members of the Anterior Cruciate Ligament (ACL) Study Group (SG).

METHODS

A survey was created and distributed among the members of the ACL SG consisting of 87 questions and 16 categories related to ACLR, including member demographics, preoperative management, primary ACLR techniques and graft choice, use of concomitant procedures and biological augmentation, postoperative rehabilitation, and more.

RESULTS

The survey was completed by the 140 members of the ACL SG. Fifty per cent of members are from Europe, 29% from the USA, 15% from the Asia-Pacific and the remaining 6% are from Latin America, the Middle East, New Zealand and Africa. Most (92%) do not believe there is a role for non-operative management of ACL tears in higher level athletes; conversely, most agree there is a role for non-operative management in lower impact athletes (92%). A single-bundle (90%) technique with hamstring autograft (53%) were most common for primary ACLR. Tunnel position varied among respondents. Sixty-one per cent do not use allograft for primary ACLR. Fifty per cent of respondents use cortical suspensory fixation on the femur, with variable responses on the tibia. Most (79%) do not use biologics in primary ACLR, while 83% think there is a selective role for extra-articular augmentation in primary ACLR. Fifty per cent prefer bone-tendon-bone autograft for revision ACLR and extra-articular augmentation is more commonly used (13% always, 26% often) than in primary ACLR (0% always, 15% often). A majority (53%) use a brace after primary ACLR. The most common responses for minimal time to return to play after primary ACLR were 6-8 months (44%) and 8-12 months (41%).

CONCLUSION

We presented the thoughts and preferences of the ACL SG on the management of ACL injuries. This survey will help to facilitate an ongoing discussion with regard to ACLR by providing global insights into the current surgical trends in ACLR.

LEVEL OF EVIDENCE

Level V, Expert Opinion.

Generalized Joint Laxity Is Associated With Increased Failure Rates of Primary Anterior Cruciate Ligament Reconstructions: A Systematic Review

PURPOSE

To investigate patients with generalized joint laxity (GJL) after primary anterior cruciate ligament reconstruction (ACLR) as to the risk of ACLR failure, graft selection success rates, and overall clinical outcomes.

METHODS

A systematic review of the PubMed and EMBASE databases was performed to identify studies published from the inception of the databases through February 4, 2020. The inclusion criteria were original studies written in English involving outcomes of patients with GJL who had undergone primary ACLR.

RESULTS

Nine studies met the inclusion criteria, which included 1,869 patients. Most underwent isolated bone-patellar tendon-bone (BPTB; n = 1062) or hamstring autograft (n = 696) ACLR. Overall, higher graft failure rates tended to occur in patients with GJL compared with patients without GJL (range per study: 6%-30% vs 0%-12.3%). Inferior results were also found patients with GJL in patient-reported outcome measures and postoperative knee stability determined by KT, Lachman, and pivot-shift tests. BPTB autografts tended to have lower failure rates than hamstring autografts in patients with GJL (range per study: 6%-21% vs 17.6%-30%). Only 1 study determined outcomes of a combined ACLR and extra-articular augmentation in patients with GJL.

CONCLUSIONS

Patients with GJL are at an increased risk of inferior outcomes and graft failure after primary ACLR. BPTB autografts may have more favorable stability outcomes compared with hamstring autografts in patients with GJL. However, the reported stability parameters and KT results, even with a BPTB autograft, remain inferior to non-GJL published results, and the added benefit of an extra-articular procedure to supplement the primary ACLR deserves consideration.

LEVEL OF EVIDENCE

Level III, systematic review of Level II and III investigations.

Lateral Extra-articular Tenodesis Contributes Little to Change In Vivo Kinematics After Anterior Cruciate Ligament Reconstruction: A Randomized Controlled Trial

BACKGROUND

Lateral extra-articular tenodesis (LET) in combination with anterior cruciate ligament (ACL) reconstruction (ACLR) has been proposed to improve residual rotatory knee instability in patients having ACL deficiency.

PURPOSE/HYPOTHESIS

The purpose was to compare the effects of isolated ACLR (iACLR) versus LET in combination with ACLR (ACLR+LET) on in vivo kinematics during downhill running. It was hypothesized that ACLR+LET would reduce the internal rotation of the reconstructed knee in comparison with iACLR.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 18 patients with ACL deficiency were included. All participants were randomly assigned to receive ACLR+ LET or iACLR during surgery. Six months and 12 months after surgery, knee joint motion during downhill running was measured using dynamic biplane radiography and a validated registration process that matched patient-specific 3-dimensional bone models to synchronized biplane radiographs. Anterior tibial translation (ATT; positive value means "anterior translation") and tibial rotation (TR) relative to the femur were calculated for both knees. The side-to-side differences (SSDs) in kinematics were also calculated (operated knee-contralateral healthy knee). The SSD value was compared between ACLR+LET and iACLR groups using a Mann-Whitney U test.

RESULTS

At 6 months after surgery, the SSD of ATT in patients who had undergone ACLR+LET (-1.9 ± 2.0 mm) was significantly greater than that in patients who had undergone iACLR (0.9 ± 2.3 mm) at 0% of the gait cycle (foot strike) (P = .031). There was no difference in ATT 12 months after surgery. Regarding TR, there were no differences between ACLR+LET and iACLR at either 6 months (P value range, .161-.605) or 12 months (P value range, .083-.279) after surgery.

CONCLUSION

LET in combination with ACLR significantly reduced ATT at the instant of foot strike during downhill running at 6 months after surgery. However, this effect was not significant at 12 months after surgery. The addition of LET to ACLR had no effect on TR at both 6 and 12 months after surgery.

CLINICAL RELEVANCE

LET in combination with ACLR may stabilize sagittal knee motion during downhill running in the early postoperation phase, but according to this study, it has no effect on 12-month in vivo kinematics.

REGISTRATION

NCT02913404 (ClinicalTrials.gov identifier).

Influence of Preoperative Tunnel Widening On the Outcomes of a Single Stage-Only Approach to Every Revision Anterior Cruciate Ligament Reconstruction: An Analysis of 409 Consecutive Patients From the SANTI Study Group

BACKGROUND

Preoperative tunnel widening is a frequently reported indication for performing a 2-stage revision anterior cruciate ligament reconstruction (ACLR) instead of a single-stage procedure. However, the strength of the available evidence to support a 2-stage strategy is low.

PURPOSE/HYPOTHESIS

The purpose was to evaluate the clinical outcomes of a single stage-only approach to revision ACLR. It was hypothesized that this approach would be associated with significant improvements from baseline in patient-reported outcome measures (PROMs) and knee stability and that there would be no significant differences in any postoperative outcomes between patients with and without preoperative tunnel widening.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A retrospective analysis was conducted of a large series of consecutive patients undergoing revision ACLR with a minimum follow-up of 2 years. Preoperative tunnel widening was assessed using digital radiographs. All patients underwent single-stage surgery with an outside-in technique, regardless of the degree of tunnel widening. Clinical outcomes were compared according to whether tunnel widening was present (either tunnel ≥12 mm) or not (both tunnels <12 mm).

RESULTS

The study included 409 patients with a mean ± SD follow-up of 69.6 ± 29.0 months. After revision ACLR, there was a significant reduction in the side-to-side anteroposterior laxity difference, from 7.7 ± 2.2 mm preoperatively to 1.2 ± 1.1 mm at 2 years (P < .001). The mean International Knee Documentation Committee (IKDC) and all subscales of the Knee injury and Osteoarthritis Outcome Score (KOOS) exceeded the thresholds for the Patient Acceptable Symptom State defined for primary ACLR. An overall 358 patients had retrievable preoperative radiographs. According to the tunnel diameter measurements, 111 patients were allocated to group A (both tunnels <12 mm) and 247 patients to group B (either/both tunnels ≥12 mm). There were no significant differences between groups with respect to anteroposterior side-to-side laxity difference, graft rupture rates, non-graft rupture related reoperations, or contralateral anterior cruciate ligament injury rates. There was also no significant difference between groups that exceeded minimal detectable change thresholds for any of the PROMs recorded (ACL-RSI [Anterior Cruciate Ligament-Return to Sports After Injury], Lysholm, Tegner, IKDC, KOOS).

CONCLUSION

A single-stage approach to revision ACLR is associated with excellent clinical results when an outside-in drilling technique is utilized. The presence of preoperative tunnel widening does not significantly influence PROMs, knee stability, graft rupture rates, or non-graft rupture related reoperation rates.

Outside-In Drilling Allows Avoidance of Two-Stage Surgery in Revision Anterior Cruciate Ligament Reconstruction

The presence of preoperative tunnel widening and/or malposition can pose technical challenges for revision anterior cruciate ligament reconstruction. This Technical Note describes the use of outside-in drilling to avoid the need for 2-stage reconstruction in the presence of tunnel widening or semi-anatomic tunnels.

The anatomy of Kaplan fibers

PURPOSE

Kaplan fibers (KF) have been described as connections between the iliotibial band and the distal femur. They are divided into two distinct structures, proximal (PKF) and distal (DKF) fibers, which may participate in the control of the rotatory knee stability. Their anatomical characteristics have not been investigated completely, in particular with respect to reconstruction procedures. The aim was to determine their anatomical characteristics and their morphological variation.

METHODS

Twenty-one nonpaired fresh frozen human cadaveric knees (from whole leg) were used for the analysis of PKF and DKF through an anterolateral approach. The anatomical relationships between the adjacent anterolateral structures were reported and anatomical characteristics of PKF and DKF (thickness, width and length) measured at 50° knee flexion under different rotational conditions (neutral: NR, Internal at 5Nm: IR applied with a dynamometric torque rig). Bony ridges of PKF and DKF were measured.

RESULTS

PKF and DKF and their respective bony ridges were individually identified in all knees studied (n = 21). The PKF and DKF were proximal and posterior to the lateral femoral epicondyle, respective distances 49.20 ± 7.38 and 27.54 ± 7.69 mm. DKF were thicker (p < 0.001), wider (p < 0.001) and longer (p < 0.001) than the PKF, regardless of the tibial rotation applied. Tensioning of KF was achieved in IR with a decrease in thickness and width, alongside fiber lengthening (p < 0.001).

CONCLUSION

PKF and DKF are distinct and constant anatomical structures of the lateral compartment of the knee, whose anatomical characteristics and their tensioning in IR presume a function of controlling rotational knee stability.