Revision Anterior Cruciate Ligament Reconstruction Research Articles

[Clinical outcome of combined over-the-top reconstruction with modified Lemaire procedure in one-stage revision anterior cruciate ligament reconstruction].

Objective: To investigate the clinical effect of over-the-top (OTT) reconstruction of the anterior cruciate ligament (ACL) combined with the modified Lemaire technique in one-stage ACL revision. Methods: It's a retrospective study. The clinical data of 37 patients who underwent one-stage revision of ACL using OTT combined with modified Lemaire technique from April 2020 to May 2023 in the Department of Sports Medicine of Xinhua Hospital Affiliated to Dalian University were retrospectively analyzed. There were 28 males and 9 females with a mean age of (32.7±5.7) years. The postoperative knee function and surgical revision effect were evaluated by subjective and objective evaluation indexes of the knee joint before and 3 months and 24 months after surgery. The subjective evaluation indexes included the International Knee Documentation Committee (IKDC) score, Lysholm score, and Tegner score; and the objective evaluation indexes included the anterior-posterior static displacement distance of the tibia, tibia-femur relative rotation angle, the Lachman test, the axial shift test, and the ratio of the loss of muscle strength of the lower limb. Results: At the final follow-up, all patients returned to pre-injury motor level, with significant improvements in IKDC scores (45.3±6.8 preoperatively, 67.5±4.7 and 93.2±2.3 at 3 months and 2 years after the operation, respectively), Lysholm scores (57.2±2.6 preoperatively, 72.6±2.9 and 89.7±3.7 at 3 months and 2 years after the operation, respectively), and Tegner scores (3.1±0.7 preoperatively, 4.9±0.6 and 5.8±1.3 at 3 months and 2 years after the operation, respectively) (all P<0.001). The anterior-posterior static displacement distance of the tibia reduced significantly [from (5.2±0.5) mm before the operation to (1.4±0.5) mm at 2 years postoperatively) (P<0.001)]; and the relative rotation angle of the tibia-femur restored to the normal physiological range, it was reduced from 6.2°±1.2° before the operation to 1.7°±0.3° 2 years after (P<0.001). The Lachman test and axial shift test at 2 years postoperatively were all negative. The muscle strength loss ratio of the affected lower limb was significantly better than that before the operation (P<0.001). Conclusion: The use of OTT reconstruction combined with modified Lemaire technique for revision of ACL in patients with ACL reconstruction failure can circumvent the tunnel problem for one-stage revision and better restore the stability and function of the knee joint, with ideal clinical results.

Lower anxiety level to perform movements after revision anterior cruciate ligament reconstruction with lateral extra-articular tenodesis compared to without lateral extra-articular tenodesis.

To evaluate the anxiety level to perform movements in patients after revision anterior cruciate ligament reconstruction (ACLR) combined with lateral extra-articular tenodesis (LET) compared to patients after revision ACLR without LET. Ninety patients who underwent revision ACLR with ipsilateral bone-patellar tendon-bone autograft and with a minimum of 12months follow-up were included in this study. Patients were divided into two groups: patients who received revision ACLR in combination with LET (revision ACLR_LET group; mean follow-up: 29.4months, range: 12-80months), and patients who received revision ACLR without LET (revision ACLR group; mean follow-up: 61.1months, range: 22-192months). All patients filled in a questionnaire about anxiety level related to physical activity and sports, the Knee injury and Osteoarthritis Outcome Score (KOOS), the International Knee Documentation Committee subjective form (IKDCsubjective), and the Tegner Activity Score. Patients in the revision ACLR_LET group had a significantly lower anxiety level to perform movements than patients in the revision ACLR group (p < 0.05). No significant differences were found in KOOS, IKDCsubjective, and Tegner Activity Scores. Patients who received LET in addition to revision ACLR have a lower anxiety level to perform movements than patients with revision ACLR alone, despite non-different subjective functional outcomes. Retrospective cohort study, Level of evidence: III.

Computer patient-specific 3D modeling and custom-made guides for revision ACL surgery.

Revision Anterior cruciate ligament reconstruction (ACLR) is a challenging surgery occurring in 3-24% of primary reconstructions. A meticulous planning to study the precise size and location of both femoral and tibial bone tunnels is mandatory. The aim of the study was to evaluate the intra- and inter-operator differences in the decision-making process between experienced surgeons after they were asked to make pre-operative planning for ACL revision reconstruction with the use of both the CT scan and a 3D printed model of the knee. Data collected from 23 consecutive patients undergoing revision of ACLR for graft failure at a single Institute between September 2018 and February 2020 were prospectively reviewed. The double-blinded collected data were presented to three board-certificate attending surgeons. Surgeons were asked to decide whether to perform one-stage or two-stage revision ACLR based on the evaluation of the CT scan images and the 3D printed custom-made models at two different rounds, T0 and T1 respectively, seven days apart one from the other. Inter-operator consensus following technical mistake was 52% at T0 and 56% at T1 using the CT scans, meanwhile concordance was 95% at T0 and 94% at T1 using the 3D models. Concordance between surgeons following new knee injury was 66% at T0 and 70% at T1 using CT scans, while concordance was 96% both at T0 and T1 using 3D models. Intra-operative variability using 3D models was extremely low: concordance at T0 and T1 was 98%. McNamar test showed a statistical significance in the use of 3D model for preoperative planning (p < 0.005). 3D printed model reliability resulted to be higher compared to CT as intra-operator surgery technique selection was not modified throughout time from T0 to T1 (p < 0.005). The use of 3D printed models had the most impact when evaluating femoral and tibial tunnels, resulting to be a useful instrument during pre-operative planning of revision ACLR between attending surgeons with medium-high workflow.

Delaying anterior cruciate ligament reconstruction for more than 3 or 6 months results in lower risk of revision surgery

BackgroundThe objective of this study is to investigate the risk of revision surgery when delaying anterior cruciate ligament reconstruction (ACLR) past 3 months or 6 months after injury.Materials and methodsA total of 30,280 patients with isolated ACLR were identified in the Danish Knee Ligament Reconstruction Registry and divided into four groups; ACLR < 3 months, > 3 months, < 6 months, or > 6 months after injury. Primary outcome was revision surgery and secondary outcome were objective and subjective clinical outcome. The 2 year relative risk, crude, and adjusted hazard ratio (HR) were calculated.ResultsComparing ACLR < 3 months to ACLR > 3 months of injury the 2 year relative risk of revision surgery was found to be 1.81 (95% CI 1.46–2.23; P < 0.001) with an adjusted hazard ratio (HR) of 1.27 (95% CI 1.12–1.44; P < 0.001). Comparing ACLR < 6 months to ACLR > 6 months of injury the 2 year relative risk of revision surgery was found to be 1.61 (95% CI 1.34–1.92; P < 0.001) with an adjusted HR of 1.27 (95% CI 1.15–1.40; P < 0.001).ConclusionThe risk of revision ACLR surgery was found to be increased when ACLR was performed within 3 months or 6 months of injury compared with later surgery. The 1 year postoperative objective knee laxity and the subjective patient-related outcome was found to be without a clinically significant difference; however, those with early ACLR (< 3 months or < 6 months) were found to have a higher activity level 1 year postoperatively. The information about increased risk of revision when having early surgery should be informed to patients when deciding timing of ACLR treatment.Level of evidence: II.

Evaluation of Failed ACL Reconstruction: An Updated Review.

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

The Periosteum–Patellar Tendon–Bone Autograft for Anatomic, Single-Bundle Anterior Cruciate Ligament Reconstruction With Press-Fit Tibial Fixation

Optimal graft choice and fixation technique are still ongoing topics of debate for primary and revision anterior cruciate ligament reconstruction. Interference screws are frequently used as graft fixation devices but can sometimes lead to tunnel widening, cyst formation, chronic inflammation, screw breakage, and persistent pain. Tibial tunnel widening is of special concern because it is often associated with graft failure. This technical note introduces a graft technique with a periosteum–patellar tendon–bone autograft and a press-fit tibial fixation approach that could be a viable option for secure anterior cruciate ligament reconstruction while offering the possibility of a quicker postoperative recovery, less pain, and a quicker return to everyday activities.

Mid-term Results of a Single-Stage Revision Anterior Cruciate Ligament Reconstruction: A Retrospective Analysis of 36 Cases

Background. Revision anterior cruciate ligament reconstruction is becoming more and more common in the knee surgery due to the annual increase in the number of primary anterior cruciate ligament reconstructions. Choosing the most suitable graft and determining the staging of the surgical treatment by preoperative assessment of the possibility of performing the most anatomical revision canals and their interposition with the primary canals are the main factors that influence treatment results.&#x0D; Aim of the study — comparative assessment of the results of using hamstring tendon and peroneus longus tendon autografts in a one-stage revision reconstruction of the anterior cruciate ligament.&#x0D; Methods. A retrospective analysis of the medical records of 36 patients who underwent revision anterior cruciate ligament reconstruction was performed. The patients were divided into two groups: in the patients of the study group (n = 19) a peroneus longus tendon (PLT) autograft was used, in the comparison group (n = 17) a hamstring tendon autograft (HT) was applied. Subjective and objective evaluation using the KOOS, IKDC, and Lysholm scales was performed, and position of the central entry points of the primary and revision canals was determined.&#x0D; There were no statistically significant differences in the objective assessment of the knee joint stability. Significantly better results of subjective assessment of the knee function according to the Lysholm and KOOS scales were obtained in the PLT group (p = 0.042 and p0.001, respectively). Position of revision canals corresponded to the standard values, but position of the femoral canal had a slight cranial and anterior displacement. It was also found that the PLT graft diameter was statistically significantly larger than the HT graft diameter (p0.001).&#x0D; Results. There were no statistically significant differences in the objective assessment of the knee joint stability. Significantly better results of subjective assessment of the knee function according to the Lysholm and KOOS scales were obtained in the PLT group (p = 0.042 and p0.001, respectively). Position of revision canals corresponded to the standard values, but position of the femoral canal had a slight cranial and anterior displacement. It was also found that the PLT graft diameter was statistically significantly larger than the HT graft diameter (p0.001).&#x0D; Conclusion. One-stage revision anterior cruciate ligament reconstruction is a safe and effective surgical procedure providing satisfactory objective and subjective clinical results. Use of peroneus longus tendon autograft allows to obtain better results in comparison with the hamstring tendon autograft.

Functional outcomes in single stage bilateral ACL reconstruction with a maximum follow up of 10 years

BackgroundBilateral ACL injuries are a rarity and there is no particular consensus on whether this rare problem has to be tackled in stages or in a single stage. There are a few studies and case reports in the literature about the outcomes in single staged bilateral Anterior cruciate ligament reconstruction (ACLR). This study is focused on functional outcomes after a single staged bilateral ACLR, as well as impact of simultaneity of the injury, meniscal tears, notch stenosis and hyperlaxity. Materials and methodsA retrospective study was conducted from 2013 to 2021. Patients with bilateral ACL injury either simultaneous or non simultaneous, with or without meniscal tears were included in this study. Pre operative diagnosis was made both clinically and by MR imaging. All patients underwent a single staged bilateral ACL reconstruction. Pre operative functional scores (IKDC and Lysholm) were taken at admission and patients were examined at regular follow ups. Final functional scores were collected in a phone interview. Results33 patients underwent bilateral ACLR in a single stage during the study period but one patient had revision ACLR in one knee and so was excluded. Of the 32 patients, 25 (78%) had non simultaneous injury and 7 (22%) had a simultaneous injury, meniscus tear was noted in 27 (84.4%), notch stenosis in 19 (59.3%) and hyperlaxity in 12 (37.5%). IKDC and Lysholm scores have improved postoperatively. No statistically significant difference was found with or without simultaneous injury or meniscus tears. ConclusionSingle stage bilateral ACL reconstruction is a safe, reproducible approach to bilateral ACL injuries whether they were simultaneous or non simultaneous or with or without meniscal tears.

Clinical Outcomes of Different Management Techniques for Medial Meniscal Type 3 Ramp Lesions in Anterior Cruciate Ligament Reconstruction: A Comparative Analysis Between All-inside Repair, Suture Hook Repair, and Lesions Left In Situ.

There is ongoing debate about the best way to manage ramp lesions at the time of anterior cruciate ligament (ACL) reconstruction (ACLR). Type 3 lesions are not visible by the transnotch approach without superior debridement, making the management debate even more problematic. The purpose of this study was to evaluate the rate of secondary surgical interventions according to the management method of a type 3 ramp lesion concomitant with primary ACLR. The hypothesis was that the rate of secondary ACL or meniscal interventions would be higher in patients who underwent all-inside repair. Cohort study; Level of evidence, 3. A retrospective analysis of all patients who underwent primary ACLR with a type 3 ramp lesion between January 2012 and May 2020, regardless of the treatment method, was performed. The main criterion analyzed in this cohort was a secondary surgical intervention, defined as revision ACLR or a reintervention of the repaired meniscus. A survivorship analysis was performed to evaluate secondary surgical interventions in 3 groups: all-inside repair, suture hook repair, and left in situ. The following data were collected preoperatively and at the last follow-up: patient characteristics, time to surgery, side-to-side difference in laxity, pivot shift, Lysholm score, subjective International Knee Documentation Committee score, Knee injury and Osteoarthritis Outcome Score, Tegner score, and meniscal repair failure rate. A total of 113 patients who underwent type 3 ramp lesion repair concomitant with ACLR were included: 52 (46.0%) in the all-inside repair group, 23 (20.4%) in the suture hook repair group, and 38 (33.6%) in the lesion left in situ group. There were 17 patients (15.0%) who underwent a secondary intervention because of ACL graft failure (n = 6) or meniscal repair failure (n = 15 [4 of whom underwent a concomitant ACL reintervention]). Overall, 62 patients (54.9%) underwent combined ACLR and anterolateral ligament reconstruction, while 51 patients (45.1%) underwent isolated ACLR. In the adjusted Cox model, the type of meniscal repair was not statistically significantly associated with secondary surgical interventions. The only risk factor for secondary surgical interventions in this cohort was isolated ACLR (hazard ratio, 8.077; P = .007). The rates of secondary surgical interventions after medial meniscal type 3 ramp lesion repair concomitant with ACLR were similar regardless of the management method of the meniscal lesion. Despite not being associated with meniscal treatment, this rate was 8 times higher for patients who underwent isolated ACLR in this cohort; this is probably because of the protection that lateral extra-articular procedures provide to the ACL graft.

Combined ACL and Anterolateral Ligament Reconstruction Using an Adjustable-Loop Fixation Device: Surgical Technique

Background: There are several techniques for the combined reconstruction of the anterior cruciate ligament (ACL) and the anterolateral ligament (ALL), but none have shown superiority. This study aims to present a surgical technique that theoretically reduces some of the risks reported in these procedures. Indications: The main indications for the ALL reconstruction include chronic ACL injuries, revision ACL reconstruction, acute ACL injuries in patients with high-grade pivot-shift (grades 2 or 3), patients involved in pivoting sports, and generalized ligament hyperlaxity or knee hyperextension. Technique Description: Hamstring tendon autografts are used for the ACL and ALL reconstruction; a common femoral ACL and ALL tunnel is made outside-in, making a short socket. A continuous looped hamstring tendon autograft attached to one button is used. The ACL is fixed with an adjustable-loop button. Through small incisions, the tibial fixation of both grafts is performed with bioabsorbable screws. Results: We present a 19-year-old professional soccer player with an acute ACL tear, with no associated meniscal or chondral lesions. Owing to his young age and high-risk sports practice, a combined ACL and ALL reconstruction was performed. The combined ACL and ALL reconstruction with a single femoral tunnel using the hamstrings tendons graft is a well-established procedure for ACL augmentation, reducing failure rates for certain risk groups, with excellent outcomes reported. The use of an adjustable-loop button on the femur is a viable option for this kind of reconstruction with postoperative stability comparable to the interference screw, classically used for this kind of reconstruction. Discussion/Conclusion: This technique has some advantages, such as the use of a short outside-in femoral socket, thus theoretically improving healing. In addition, this lowers the risk of lateral collateral ligament injury, and since the ileotibial band graft is not used, the risk of injuring the lateral inferior genicular vessels and the peroneal nerve is theoretically reduced. Besides, using an adjustable-loop cortical button in the femur can theoretically reduce potential complications such as screw migration, soft-tissue impingement, femoral-site pain, and implant removal. Finally, the reconstruction is done with small incisions, improving the aesthetic result and postoperative pain. Considering all the aforementioned factors, this technique theoretically offers some benefits. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Factors Associated With Knee Extension Strength Symmetry After Anterior Cruciate Ligament Reconstruction With Quadriceps Tendon Autograft.

Diminished postoperative knee extension strength may occur after anterior cruciate ligament reconstruction (ACLR) with quadriceps tendon (QT) autograft. Factors influencing the restoration of knee extensor strength after ACLR with QT autograft remain undefined. To identify factors that influence knee extensor strength after ACLR with QT autograft. Case-control study; Level of evidence, 3. The authors performed a retrospective review of patients who underwent primary ACLR with QT autograft at a single institution between 2010 and 2021. Patients were included if they completed electromechanical dynamometer testing at least 6 months after surgery. Exclusion criteria consisted of revision ACLR, <6 months of follow-up, concomitant procedure (osteotomy, cartilage restoration), and concomitant ligamentous injury requiring surgery. Knee extension limb symmetry index (LSI) was obtained by comparing the peak torque of the operated and nonoperated extremities. Univariable and multivariable analyses were performed to identify factors associated with knee extension LSI in the patient, injury, rehabilitation, and preoperative patient-reported outcomes score domains. A total of 107 patients (58 male; mean age, 22.8 years) were included. Mean knee extension LSI of the overall cohort was 0.82 ± 0.18 at 7.5 ± 2.0 months; 35 patients (33%) had a value of ≥0.90. Multivariable analysis demonstrated significant negative associations between knee extension LSI and female sex (-0.12; P < .001), increased age at the time of surgery (-0.01; P = .018), and larger QT graft width (-0.049; P = .053). Factors influencing knee extensor LSI after ACLR with QT autograft in this study population spanned patient and surgical factors, including female sex, older age at the time of surgery, and wider graft harvest. Surgeons should consider the association between these factors and lower postoperative knee extensor LSI to optimize patient outcomes.

Difference of Knee Strength Recovery Between Revision and Primary ACL Reconstruction.

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

The Influence of Tibial Tubercle–Sparing Slope-Reducing Osteotomy on Patellar Height in Patients Undergoing Revision ACL Reconstruction

Background: A posterior tibial slope (PTS) >12° is an independent risk factor for anterior cruciate ligament (ACL) graft rupture, and a high tibial osteotomy (HTO) for slope correction can help avoid it. Management of patellar height is of major concern when performing HTO. Purpose: To evaluate the effect of tibial tubercle–sparing anterior closing-wedge osteotomy on patellar height in revision ACL reconstruction (ACLR). Study Design: Case series; Level of evidence, 4. Methods: Patients who underwent arthroscopic revision ACLR combined with retro–tibial tubercle anterior closing-wedge HTO (ACW-HTO) between January 1, 2016, and March 31, 2021, were assessed for eligibility. Patellar height was measured on full weightbearing lateral radiographs according to the Insall-Salvati index (ISI) and Caton-Deschamps index (CDI) or frontal radiographs using the femoral patellar height index. The PTS was evaluated using the proximal anatomic axis of the tibia on standard short lateral radiographs. The delta (postoperative – preoperative) and the ratio (preoperative/postoperative) of the 3 patellar height indices and PTS were calculated. Preoperative and postoperative patellar heights were compared using independent t tests for each index. Also investigated was whether patients changed patellar height category (baja, normal, or alta) after slope osteotomy. Results: Among 475 revision ACLRs, 47 tibial tubercle–sparing ACW-HTOs were retained for analysis. No significant difference in patellar height was found between pre- and postoperative radiographs regardless of the index (preoperative – postoperative) (ISI: 1.0 ± 0.2 – 0.9 ± 0.2, P = .1729; CDI: 1.0 ± 0.2 – 1.0 ± 0.2, P = .4034; femoral patellar height index: 1.5 ± 0.2 – 1.5 ± 0.2; P = .5130). Fifteen patients (31.9%) exhibited a postoperative change in their patellar height category when measured by the ISI (6 moved up a category, 9 moved down one), and 18 patients (38.3%) changed category according to the CDI (10 moved up a category, 8 moved down one). No significant difference was found between pre- and postoperative patellar height among these patients (ISI: P = .2418; CDI: P = .3005). Conclusion: Changes in patellar height ratio are common after tibial tubercle–sparing ACW-HTO in patients undergoing revision ACLR. The clinical effect of these changes is unknown, and further study is needed to investigate whether they may result in patellofemoral symptoms.

Unsupervised Machine Learning of the Combined Danish and Norwegian Knee Ligament Registers: Identification of 5 Distinct Patient Groups With Differing ACL Revision Rates

Background: Most clinical machine learning applications use a supervised learning approach using labeled variables. In contrast, unsupervised learning enables pattern detection without a prespecified outcome. Purpose/Hypothesis: The purpose of this study was to apply unsupervised learning to the combined Danish and Norwegian knee ligament register (KLR) with the goal of detecting distinct subgroups. It was hypothesized that resulting groups would have differing rates of subsequent anterior cruciate ligament reconstruction (ACLR) revision. Study Design: Cohort study; Level of evidence, 3. Methods: K-prototypes clustering was performed on the complete case KLR data. After performing the unsupervised learning analysis, the authors defined clinically relevant characteristics of each cluster using variable summaries, surgeons’ domain knowledge, and Shapley Additive exPlanations analysis. Results: Five clusters were identified. Cluster 1 (revision rate, 9.9%) patients were young (mean age, 22 years; SD, 6 years), received hamstring tendon (HT) autograft (91%), and had lower baseline Knee injury and Osteoarthritis Outcome Score (KOOS) Sport and Recreation (Sports) scores (mean, 25.0; SD, 15.6). Cluster 2 (revision rate, 6.9%) patients received HT autograft (89%) and had higher baseline KOOS Sports scores (mean, 67.2; SD, 16.5). Cluster 3 (revision rate, 4.7%) patients received bone–patellar tendon–bone (BPTB) or quadriceps tendon (QT) autograft (94%) and had higher baseline KOOS Sports scores (mean, 65.8; SD, 16.4). Cluster 4 (revision rate, 4.1%) patients received BPTB or QT autograft (88%) and had low baseline KOOS Sports scores (mean, 20.5; SD, 14.0). Cluster 5 (revision rate, 3.1%) patients were older (mean age, 42 years; SD, 7 years), received HT autograft (89%), and had low baseline KOOS Sports scores (mean, 23.4; SD, 17.6). Conclusion: Unsupervised learning identified 5 distinct KLR patient subgroups and each grouping was associated with a unique ACLR revision rate. Patients can be approximately classified into 1 of the 5 clusters based on only 3 variables: age, graft choice (HT, BPTB, or QT autograft), and preoperative KOOS Sports subscale score. If externally validated, the resulting groupings may enable quick risk stratification for future patients undergoing ACLR in the clinical setting. Patients in cluster 1 are considered high risk (9.9%), cluster 2 patients medium risk (6.9%), and patients in clusters 3 to 5 low risk (3.1%-4.7%) for revision ACLR.

Revision ACL reconstruction in female athletes: current concepts

The challenge of revision anterior cruciate ligament (ACL) reconstruction lies in its complexity, varied presentation, and technical intricacies. A successful ACL reconstruction should allow patients to safely return to preinjury activities. However, it is only sometimes simple, and many risk factors and concurrent pathologies come into play. Evaluating and analysing the cause of failure and associated conditions is paramount to addressing them effectively. Despite a plethora of research and improvements in knowledge and technology, e gaps exist in issues such as optimal techniques of revision surgery, graft options, fixation, concurrent procedures, rehabilitation and protocol for return to sports of high-level athletes. Female athletes need additional focus since they are at higher risk of re-injury, suboptimal clinical outcomes, and lower rates of return to sport following revision reconstruction. Our understanding about injury prevention and the protection of ACL grafts in female athletes needs to be improved. This review focuses on the current state of revision ACL surgery in female athletes and provides recommendations and future directions for optimising outcomes in this high-risk group.

Lateral Extra-articular Tenodesis Does Not Decrease Graft Failure in Revision Anterior Cruciate Ligament Reconstruction When Combined With Quadriceps or Patellar Tendon Grafts

PurposeThe purpose of this study was to compare return to sports, graft failure rates, and clinical outcomes in patients who underwent to a revision ACL reconstruction (R-ACLR) and additional lateral extra-articular tenodesis (LET) compared to isolated R-ACLR. MethodsA retrospective review of medical records of patients who underwent R-ACLR with or without a modified Lemaire LET was performed. Seventy-four patients with ≥ 2 years follow-up, who had a high-grade positive pivot shift test were included. Concomitant procedures such as meniscectomy and meniscal repair were collected along with any complications and/or graft failure. Knee Injury and Osteoarthritis Outcome Score (KOOS) and the International Knee Documentation Committee (IKDC) Subjective Knee Form were collected. The ability to return to sports was defined as fully, partially, or not returned. ResultsThirty-nine patients underwent isolated R-ACLR (mean age (SD±) 29.2 ±12.2) and 35 had an additional LET (24.6 ±7.4). The mean length of follow-up in the R-ACLR group was 56.6 ±26.5 months compared to 44.3 ±17.6 months (p = 0.02*) (range 24 – 120 months) in the R-ACLR+LET group. PROMs were higher in the LET group with KOOS ADL (93.5 ± 2.0; 97.2 ± 1.6; p=0.03) and KOOS Sport (63.0 ± 3.6; 74.3 ± 3.8; p=0.05) subdomains reaching statistical significance. No other differences were found in the other KOOS subdomains or IKDC scores. Failure rates were not significantly different between the groups (12.8% for R-ACLR vs 11.4% for R-ACLR+LET; p=0.99). Thirteen (72.2%) patients in the R-ACLR group and 14 (60.8%) patients in the R-ACLR+LET group did not return to sports. ConclusionR-ACLR with additional LET showed a similar failure rate and RTS compared to isolated R-ACLR following failed ACLR. The R-ACLR + LET group demonstrated better functional results with significantly higher activities of daily living, and sport and recreation KOOS subdomain scores. However, the present study was unable to recommend the modified Lemaire LET to be used routinely in revision ACLR patients. Level of EvidenceIII, retrospective comparative therapeutic trial

Primary Versus Revision ACL Reconstruction Using Quadriceps Autograft: A Matched-Control Cohort Study.

The incidence of anterior cruciate ligament (ACL) reconstruction is increasing, and quadriceps tendon (QT) autograft is gaining popularity for both primary and revision ACL reconstruction. To evaluate the differences in the patient-reported functional outcomes, concomitant injuries, and graft failure in primary versus revision ACL surgery using QT autograft. Cohort study; Level of evidence, 3. A total of 376 patients with primary ACL reconstruction and 138 patients with revision ACL reconstruction were retrospectively retrieved from a prospectively collected ACL registry. A minimally invasive technique was used for QT autograft harvesting. The surgical procedure and rehabilitation protocol were identical in both groups. To maintain a homogeneous cohort for the study, the groups were matched by age, sex, and preinjury outcome scores (Lysholm knee score, Tegner activity level, and visual analog scale [VAS] for pain). Initial baseline assessments of outcome scores were compared with scores collected at the 2-year postoperative mark. The mean age of the primary group and revision group was 32.9 ± 10.2 years (range, 18-55 years) and 32.3 ± 9.9 years (range, 19-55 years) respectively. Significant preinjury to postoperative improvements were noted in Lysholm (88.2 ± 16.4 vs 83.5 ± 15.0; P = .007) and VAS pain (0.9 ± 1.3 vs 1.5 ± 1.6; P = .001) scores after primary ACL reconstruction compared with revision reconstruction. However, no significant difference was found in Tegner activity level (6.7 ± 1.8 vs 5.9 ± 1.8; P > .430). Primary ACL injury was associated with significantly higher concomitant medial collateral ligament injuries (P = .019), while the revision group was associated with significantly higher concomitant cartilage (P = .001) and meniscal (P = .003) injuries. A significantly higher graft failure rate was noted in the revision group compared with the primary ACL reconstruction group (13.0% vs 5.6%; P = .005). Both primary and revision ACL reconstruction with QT autograft had acceptable functional outcomes. The primary group had better outcomes than the revision group, possibly due to the lower prevalence of meniscal and cartilage injuries in the primary group compared with the revision group. The revision group was associated with higher graft failure than the primary group. QT autograft is a viable graft choice for both primary and revision ACL reconstruction.

Association of Remaining Anterior Knee Laxity With Inferior Outcomes After Revision ACL Reconstruction.

The relationship between remaining anterior knee laxity and poorer clinical outcomes after anterior cruciate ligament reconstruction (ACLR) may be underrated, and the criteria for failure of revision ACLR have not been defined. To evaluate a possible association between remaining knee laxity and functional scores in patients after revision ACLR. We hypothesized that a postoperative side-to-side-difference (SSD) in knee laxity of ≥6 mm will be an objective parameter for failure. Cohort study; Level of evidence, 3. A total of 200 patients (77 women and 123 men; mean age, 30.8 ± 11 years; range, 18-61 years) who underwent revision ACLR between 2016 and 2019 were evaluated; The mean follow-up period was 30.2 ± 9 months (range, 24-67 months). Patients were divided into 3 groups according to postoperative SSD (<3 mm, 3-5 mm, or ≥6 mm). Preoperative and postoperative outcome measures (Lachman, pivot shift, visual analog scale [VAS] for pain, Tegner, Lysholm, International Knee Documentation Committee, and Knee injury and Osteoarthritis Outcome Score) were compared between the groups. Of the 200 patients, 74% (n = 148) had a postoperative SSD of <3 mm at the latest follow-up, 19.5% (n = 39) had a postoperative SSD of 3 to 5 mm, and 6.5% (n = 13) had a postoperative SSD of ≥6 mm. Patients in all groups saw significant pre- to postoperative reductions in positive Lachman and pivot-shift tests as well as significant improvements in VAS pain, Lysholm, and Tegner scores (P < .001 for all). All postoperative functional scores of the patients with SSDs of <3 mm and 3-5 mm were significantly increased compared with those of patients with an SSD of ≥6 mm (P≤ .01 for all). In patients following revision ACLR, anterior and rotational knee laxity were successfully reduced while increasing postoperative functional outcomes. A remaining postoperative SSD of ≥6 mm was associated with inferior patient outcomes compared with an SSD <6 mm. An SSD of ≥6 mm represents an objective parameter in the definition of failure of revision ACLR.

Meniscal Repair in the Setting of Revision Anterior Cruciate Ligament Reconstruction: 6-Year Follow-up Results from the MARS Cohort

Objectives: Meniscal preservation has been demonstrated to contribute to long term knee health and has been a successful intervention in the isolated and ACL reconstructed patient. The long-term results of meniscus repair in the setting of revision ACL reconstruction have yet to be documented. The purpose of this study is to report the incidence of meniscal repair failures at 6-year follow-up in a cohort of patients who underwent concurrent revision ACL reconstruction and meniscal repair. Methods: All revision ACL reconstructions with concomitant meniscal repair cases from a multicenter group between 2006 and 2011 were selected. Six-year follow-up was obtained by both phone and email to determine whether any subsequent surgery had occurred to either knee since their initial revision ACL reconstruction. If so, operative reports were obtained, whenever possible, to verify pathologic condition and treatment. Results: In total, 221 patients from 1234 revision ACL reconstructions underwent concurrent meniscal repairs (18% of the cohort). There were 238 repairs performed: 173 medial and 65 lateral. The vast majority of these repairs (n=181; 76%) were performed with an all-inside technique. Baseline patient and surgical characteristics of this group are reported (Tables 1, 2). Six-year surgical follow-up was obtained on 77% (171/221) of the cohort. Overall, the meniscal repair failure rate defined as reoperation was 13% (31/235) at 6 years. Of the 31 failures, 28 were medial (24 all-inside, 4 inside-out; 16% failure rate) and 3 were lateral (2 all-inside, 1 inside-out; 4.6% failure rate; Table 2). Three medial failures were treated in conjunction with a subsequent repeat revision reconstruction. The mean (SD) time to failure for the medial repairs was 2.6 (1.7) years, while the time to failure for the lateral repairs was 1.6 (1.8) years. Medial tears underwent reoperation for failure at a statistically significant higher rate than lateral tears (16% versus 4.6%; p&lt;0.001). Conclusions: Meniscus repair in the revision ACL setting is a successful treatment option when clinically indicated with low failure rates. At 6-year follow-up, overall meniscal failure rate as defined by reoperation was 13% in this revision cohort. Failure rates for medial tears (16%) were higher than for lateral tears (4.6%), which aligns with previous studies both in the revision and primary setting.

Less Subsequent Revision Anterior Cruciate Ligament (ACL) Reconstruction Following Primary Bone–Patellar Tendon–Bone ACL Reconstruction with Suture Tape Augmentation—A Retrospective Comparative Therapeutic Trial With 5-Year Follow-up

Less Subsequent Revision Anterior Cruciate Ligament (ACL) Reconstruction Following Primary Bone–Patellar Tendon–Bone ACL Reconstruction with Suture Tape Augmentation—A Retrospective Comparative Therapeutic Trial With 5-Year Follow-up