Revision Anterior Cruciate Ligament Surgery Research Articles

Over-the-Top Double-Bundle Revision Anterior Cruciate Ligament Reconstruction Technique With Hybrid Hamstring Tendon Autograft-Allograft and Associated Lateral Extra-articular Tenodesis

Revision anterior cruciate ligament (ACL) presents many technical challenges that are not commonly seen in primary ACL reconstruction. The purpose of this article is to describe an alternative technique consisting of over-the-top double-bundle ACL revision combined with lateral extra-articular tenodesis using hybrid hamstring tendon autograft-allograft. This technique provides a valid treatment option in ACL revision surgery.

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.

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.

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.

Radiographic Investigation of Coronal Plane and Patellar Height and Changes Following Tibial Deflection Osteotomy for Correction of Tibial Slope in Combination With ACL Reconstruction

Background: A tibial deflexion osteotomy (TDO) is performed to decrease the sagittal tibial slope to reduce the relative risk of anterior cruciate ligament (ACL) reconstruction (ACLR) graft failure. Given that coronal plane osteotomies can cause consequential changes in the sagittal plane to patellar height and tibial slope, potential changes to coronal plane alignment and patellar height can result after a sagittal plane osteotomy. Purpose: To compare preoperative and postoperative coronal plane alignment after TDO, as well as to analyze the effect of the osteotomy on patellar height. Study Design: Case series; Level of evidence, 4. Methods: This study was conducted on a consecutive series of patients with primary and revision ACLR with concomitant TDO between 2011 and 2022. Inclusion criteria were 1-stage autograft ACLR combined with supratubercular TDO with pre- and 3 months postoperative radiographs of sufficient quality. Indications for TDO were anterior instability requiring ACL revision surgery and a posterior tibial slope (PTS) >9° or a PTS >14° in the primary ACL surgery patients. Anteroposterior and lateral knee radiographs were reviewed, and the medial proximal tibial angle (MPTA), PTS, Caton-Deschamps index (CDI), and modified Insall-Salvati ratio were measured directly from the radiographs by 2 independent reviewers. Results: A total of 68 patients were included in this study. Pre- and postoperative radiographs were performed 1 month before and 3 months after surgery, respectively. There was a significant increase in the mean MPTA of 0.95° varus (SD, 2.1°; range, increase of 4.23° valgus to increase of 7.74° varus; P < .01), a decreased PTS of 8.86° (SD, 3.03°; P < .01), and an increased CDI of 0.08 (range, decrease of 0.27 to increase of 0.64) (P < .01; SD, 0.17) in patients undergoing TDO. Insall-Salvati ratio measurements showed no difference. There was good intra- and interobserver reliability, with intraclass correlation coefficients of 0.97 and 0.91 for MPTA, 0.97 and 0.87 for PTS, 0.87 and 0.93 for CDI, and 0.88 and 0.76 the Insall-Salvati ratio. Conclusion: This study, the largest series on TDO for ACLR, demonstrates that the TDO can be performed safely without large changes to coronal alignment or patellar height. The tibial slope was reduced by a mean of 8.86° (range, 2.3°-11.5°; P < .01). The TDO produces a small statistically significant change to coronal alignment, inducing a mean increased varus of <1° and an increased patellar height of 0.1 CDI. Therefore, TDO can be performed safely without dramatic changes to coronal alignment or patellar height, this study highlights technical aspects to minimize iatrogenic varus.

Intra- and interobserver reliability of two classification systems for posterolateral tibial plateau fractures in the setting of an ACL rupture

BackgroundPosterolateral tibial plateau impaction fractures occur frequently associated with anterior cruciate ligament (ACL) tears. Some authors advocate operative treatment of high-grade impaction fractures, which has led to the development of classification systems. Our study aims (1) to describe and compare the intra- and interobserver reliability of the two most used classifications and (2) to assess correlations between the grade of bony posterolateral tibial injury, patient characteristics and short-to mid-term revision rate after ACL reconstruction. Materials and methodsIn a retrospective series of 163 patients who underwent ACL reconstruction, two reviewers independently evaluated the preoperative MRI scans. Conform the Menzdorf and Bernholt classification the presence and grade of an associated posterolateral impaction fracture were assessed. Statistical analyses were performed to test for both study hypotheses. Results171 primary ACL cases were evaluated. Mean follow-up time was 41 months (range 12–154, SD = 17.1). Mean age was 32 years (range 13–59, SD = 12). Posterolateral impaction fractures were present in 111 (64.9 %) and 120 (70.0 %) cases, according to the Menzdorf and Bernholt classification. A Segond fracture was present in 19 (11.1 %) cases. Kappa value was 0.47 for intra- and 0.52 for the interobserver reliability for the Menzdorf classification (moderate reliability). For the Bernholt classification kappa values were 0.66 and 0.61, respectively (good reliability). A Segond fracture correlated significantly with the presence of a posterolateral impaction fracture (p < 0.05). A significant association was present between patients necessitating ACL revision surgery and patients for whom operative intervention for the posterolateral impression was advised following the Menzdorf classification (p < 0.001). ConclusionInter- and intraobserver reliability testing for classifying posterolateral tibial fractures resulted in moderate to good reliability. High-grade posterolateral tibial fractures should be identified, selective treatment should be considered as they are associated with higher revision rates after ACL reconstruction if left untreated.

Prevalence and Predictors of Concomitant Meniscal and Ligamentous Injuries Associated With ACL Surgery: An Analysis of 20 Years of ACL Reconstruction at a Tertiary Care Children’s Hospital

Background: There is an increasing rate of procedures being performed for concomitant injuries during anterior cruciate ligament (ACL) surgery. Few studies have examined risk factors for these associated injuries in young patients. Hypothesis: There are patient-related factors predictive of concomitant knee pathology that differ between age-based cohorts. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Natural language processing was used to extract clinical variables from available notes of patients undergoing ACL surgery between 2000 and 2020 at a single institution (5174 ACL surgeries; mean age, 17 ± 4 years; 53.1% female; accuracy, >98%). Patients were stratified to pediatric (5-13 years), adolescent (14-19 years), and young adult (20-35 years) cohorts. Logistic regression was used to determine predictors of concomitant injury to the menisci, medial collateral ligament (MCL), posterolateral corner (PLC), and posterior cruciate ligament (PCL). Results: Between 2000 and 2020, 54% of pediatric, 71% of adolescent, and 70% of adult patients had ≥1 concomitant soft tissue injury. In children and adolescents, increased age was consistently predictive of sustaining a concomitant injury (P < .02). Female children had increased odds of concomitant medial meniscal injury, while female adults had decreased odds (P≤ .046). Adolescent and adult female patients had decreased odds of concomitant lateral meniscal injury (P≤ .027). Female children had increased odds of injury to the MCL (P = .015), whereas female children and adolescents had decreased odds of PCL injury (P≤ .044). Adolescents undergoing revision ACL surgery had increased odds of meniscal injury (P≤ .001) and decreased odds of concomitant MCL injury (P = .028). Increased body mass index (BMI) was associated with increased odds of concomitant medial meniscal injury in all cohorts (P≤ .041), lateral meniscal injury in adults (P = .045), and PLC injury in children (P = .016). Contact injuries were associated with increased odds of MCL injury in adolescents (P = .017) and PLC injury in adolescents and adults (P < .014). Conclusion: These findings support the hypothesis, as there were multiple factors that significantly affected the risk of concomitant injuries that differed between cohorts. Increased age, BMI, and contact injury history were generally associated with increased odds of sustaining a concomitant injury, whereas female sex and revision ACL surgery had mixed effects. Further studies are essential to investigate the sex-based differences in risk for concomitant injuries and to develop tailored treatment plans that minimize the risk of secondary ACL injury.

One-stage anterior cruciate ligament revision surgery after primary failed double-bundle reconstruction: a systematic review.

Anterior cruciate ligament (ACL) revision surgery after failed double-bundle (DB) reconstruction is a challenging procedure. This study aimed to systematically review the research on ACL revision surgery following failed DB reconstruction, providing an overview on indications, surgical techniques, clinical outcomes and potential pitfalls occurring while performing this therapeutic approach. Literature published from exception to February 2023 was searched in the Pubmed/MEDLINE, Embase and CINAHL databases. Studies in English reporting on patients who underwent ACL revision surgery after prior failed DB reconstruction were considered. Review articles and expert opinion or editorial pieces were excluded. Outcomes of interest included indications and pre-operative planning, surgical technique and associated procedures, type of revision surgery (either one- or two-stage), graft choice, clinical and functional outcomes, rate of complications, failure rate. Overall, 4 studies met all the inclusion criteria for this review. All were published between 2007 and 2020. The search resulted in two retrospective comparative studies, one case series, and one case report. Average follow-up periods ranged from 24 to 45months. From these studies, 66 patients (66 knees) were identified. One-stage revision surgery was performed in 64 on 66 patients (97%) with pathologic laxity following DB ACL reconstruction. Most frequently reported outcome was Lysholm score in five studies: average postoperative Lysholm score ranged from 90.5 to 91.0 while Tegner activity level ranged from 5.6 to 7.0. In 4 patients (6%) re-revision surgery was performed due to graft re-rupture. One-stage ACL revision surgery following DB ACL reconstruction appears feasible providing satisfying outcomes and limited complications. The literature on this subject is limited and further comparative studies reporting long-term outcomes are needed, as high-level studies on this topic are still lacking.

Allogenous Bone Grafting Technique for Staged Revision Anterior Cruciate Ligament Surgery

Background: Tunnel widening, slightly malplaced former tunnels or bone loss due to hardware removal might prevent a 1-stage anterior cruciate ligament (ACL) revision procedure due to tunnel convergence or challenging graft fixation. A range of graft sources and bone grafting techniques are described—all with their strengths and limitations. Common autograft techniques come with substantial donor site morbidity that might hinder postoperative rehabilitation. Indications: Graft tunnel issues might prompt the need for structural grafts and a 2-stage ACL revision approach. The use of the current dowel allograft technique gives a flexible approach where 1 or several cylindrical grafts can be placed in prepared sockets for reliable bony ingrowth. Technique Description: Using femoral head allografts and cannulated coring reamers, multiple bone dowels (up to 6) can give a flexible and adaptable bone grafting situation. The intra-articular tunnels are dilated, and dowels are produced to allow a press-fit fixation that facilitates good bone healing. Removal of sclerotic bone and microfracture is key to allow optimal bone-to-bone healing. Use of cannulas inserted through the arthroscopic portals and tamps plug advancement will give a reliable graft deployment without dowel breakage. Results: The current authors have used this uniform technique for 119 patients since 2014. All cases displayed good bony healing at 5 months after surgery on computed tomography and radiographs, and 115 out of 119 went on to have a stage 2 revision ACL surgery at 6 months spacing from the bone grafting. The most common reason for not going through the second-stage revision was improvement of symptoms due to graft removal and bone grafting during the first surgery. Discussion/Conclusion: The current allograft dowel bone grafting allows for a flexible bone grafting in cases where a 1-step ACL revision procedure is not feasible. Reliable bony ingrowth is seen in the current cohort allowing the final step of ACL revision at 6 months spacing from bone grafting. 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.

Relationship between graft failure following anterior cruciate ligament reconstruction and hamstring autograft diameter.

With the increase in the number of individuals participating in sports, anterior cruciate ligament (ACL) injuries are also increasing gradually and the number of patients requiring surgical treatment is increasing in parallel. The primary aim of this study was to investigate the relationship between the need for revision surgery and graft diameter following primary ACL reconstruction (ACLR) using hamstring autografts. The secondary aim of the study was to clarify relationships between anthropometric characteristics and graft diameter. Patients who underwent ACLR with hamstring autografts were included in this retrospective study. The age, body mass index, height, and weight of all patients were recorded preoperatively and the diameters of the grafts were recorded during surgery. The relationship between revision rate and graft diameter and the relationships between anthropometric measurements and graft diameter were investigated for these patients at least one year after surgery. This study included 58 people with graft diameters of ≤7 mm and 261 people with graft diameters of >7 mm. A statistically significant difference was found between the graft diameters of the group that needed revision surgery and the group that did not (p<0.001). A positive relationship was also found between the patient's height and graft diameter (r=0.168). In this study, it was found that the risk of ACL revision surgery increased by 5.5 times among patients with graft diameters of ≤7 mm. The positive relationship between the patient's height and graft diameter can make a significant difference in terms of the need for revision surgery.

Management of Bone Loss and Tunnel Widening in Revision ACL Reconstruction.

➤ Both mechanical and biological factors can contribute to bone loss and tunnel widening following primary anterior cruciate ligament (ACL) reconstruction.➤ Revision ACL surgery success is dependent on graft position, fixation, and biological incorporation.➤ Both 1-stage and 2-stage revision ACL reconstructions can be successful in correctly indicated patients.➤ Potential future solutions may involve the incorporation of biological agents to enhance revision ACL surgery, including the use of bone marrow aspirate concentrate, platelet-rich plasma, and bone morphogenetic protein-2.

Poster 333: Outcomes of Anterior Closing Wedge High Tibial Osteotomy in Patients Undergoing ACL Revision Reconstruction

Objectives: Graft failure rates following anterior cruciate ligament (ACL) reconstruction have been reported up to 30%. According to the literature, one anatomic variant linked to graft reinjury is a high posterior tibial slope. As a result, surgeons are exploring the effectiveness of slope reducing high tibial osteotomy (HTO) to reduce the subsequent reinjury risk. While cadaveric models indicate that this procedure decreases the forces across the ACL graft, there is limited evidence demonstrating its efficacy in clinical trials. Therefore, the purpose of this study was to compare self-reported patient outcomes between patients undergoing ACL revision surgery with a slope reducing high tibial osteotomy (ACL+HTO) and matched controls undergoing revision ACL reconstruction without slope reducing HTO. We hypothesized that patients undergoing ACL+HTO would exhibit similar outcomes with a low failure rate when compared to their matched counterparts. Methods: A retrospective matched-case control study was conducted for patients undergoing ACL revision reconstruction from 2018 to 2021, utilizing a single surgeon database (n = 1,781). Patients in the HTO group were included if they were at least one year out from surgical ACL reconstruction and slope reducing osteotomy. Patients were excluded if they had a primary ACL reconstruction or no concomitant ACL reconstruction with an HTO. Patients in the ACL+HTO group were age, gender, and setting-matched to a control group of patients undergoing revision ACL reconstruction. Descriptive patient demographic and surgical data were obtained, including pre/postoperative posterior tibial slope (o) for the HTO group. Complications and injury surveillance was conducted throughout the postoperative follow-up period. Primary outcome measures included the Single Assessment Numeric Scale (SANE), and graft failure rates at 24 months. Secondary outcomes included return to sport rate and level, and postoperative complications (infection, loss of motion, deep vein thrombosis, etc). Generalized linear models were conducted using parametric and nonparametric equivalents to compare baseline and outcome measures between groups with an a-priori alpha level of .05. Results: From a group of 364 revision ACL reconstructions, 9 patients met the inclusion criteria for the ACL+HTO group (Table 1). This group was age, gender and revision matched to 30 patients in the control group. Baseline comparisons revealed that the ACL control group weighed more than the experimental group (198.2 ±26.4 vs 183.7 ±21.7, P &lt;.001), however all other comparisons were not statistically different. The mean pre op posterior tibial slope was 19.2o ±4.1o and 7.7o ±2.3o following HTO (mean diff: -11.5o, P &lt;.001). Mean time to follow-up was 1.82 ±0.3 years. At follow-up, there were no statistical differences in self-reported knee function (SANE score), graft reinjury rate, rate of return to sport, or level of return to sport between groups (Table 2). There were no graft reinjuries reported in the ACL+HTO group, and approximately 85.8% returned to some level of sporting activity with 42% returning to a level I or II cutting and pivoting sport. Conclusions: Preliminary evidence provided in the current study suggests that slope reducing HTO in the setting of revision ACL reconstruction for large posterior tibial slope deformities is effective at correcting malalignment and avoiding graft failure out to 2 years. This procedure also holds promise to allow a majority of patients to return to various levels of sporting activities. To our knowledge, this is the first comparative study comparing the intermediate outcomes of this subpopulation to a matched revision ACL cohort. While these data do provide evidence for ongoing investigation, it is important to note that this pilot study is underpowered and we strongly recommend the performance of larger clinical trials to confirm these results. [Table: see text][Table: see text]

Poster 350: Outcomes of Anterior Closing Wedge High Tibial Osteotomy in Patients Undergoing Revision ACL Reconstruction

Objectives: Graft failure rates following anterior cruciate ligament (ACL) reconstruction have been reported up to 30%. According to the literature, one anatomic variant linked to graft reinjury is a high posterior tibial slope. As a result, surgeons are exploring the effectiveness of slope reducing high tibial osteotomy (HTO) to reduce the subsequent reinjury risk. While cadaveric models indicate that this procedure decreases the forces across the ACL graft, there is limited evidence demonstrating its efficacy in clinical trials. Therefore, the purpose of this study was to compare self-reported patient outcomes between patients undergoing ACL revision surgery with a slope reducing high tibial osteotomy and matched controls undergoing revision ACL reconstruction without slope reducing HTO. We hypothesized that patients undergoing ACL+HTO would exhibit similar outcomes with a low failure rate when compared to their matched counterparts. Methods: A retrospective matched-case control study was conducted for patients undergoing ACL revision reconstruction from 2018 to 2021, utilizing a single surgeon database (n = 1,781). Patients in the HTO group were included if they were at least one year out from surgical ACL reconstruction and slope reducing osteotomy. Patients were excluded if they were undergoing primary ACL reconstruction or no concomitant ACL reconstruction. Patients in the ACL+HTO group were age, gender, and setting-matched to a control group of patients undergoing revision ACL reconstruction. Descriptive patient demographic and surgical data were obtained, including pre/postoperative posterior tibial slope(o) for the HTO group. Complications and injury surveillance was conducted throughout the postoperative follow-up period. Primary outcome measures included the Single Assessment Numeric Scale (SANE), and graft failure rates at 24 months. Secondary outcomes included return to sport rate/level and postoperative complications (infection, loss of motion, deep vein thrombosis, etc). Generalized linear models were conducted using parametric and nonparametric equivalents to compare baseline and outcome measures between groups with an a-priori alpha level of .05. Results: From a group of 364 revision ACL reconstructions, 9 patients met the inclusion criteria for the ACL+HTO group (Table 1). This group was age, gender and revision matched to 30 patients in the control group. Baseline comparisons revealed that the ACL control group weighed more than the experimental group (198.2 ±26.4 vs 183.7 ±21.7, P &lt;.001), however all other comparisons were not statistically different. The mean pre operative posterior tibial slope was 19.2o ±4.1o and 7.7o ±2.3o following HTO (mean diff: -11.5o, P &lt;.001). Mean time to follow-up was 1.82 ±0.3 years. At follow-up, there were no statistical differences in self-reported knee function (SANE score), graft reinjury rate, rate of return-to- sport, or level of return to sport between groups (Table 3). There were no graft reinjuries reported in the ACL+HTO group and approximately 85.8% returned to some level of sporting activity with 42% returning to a level I or II cutting and pivoting sport. Conclusions: Preliminary evidence provided in the current study suggests that slope reducing HTO in the setting of revision ACL reconstruction for large posterior tibial slope deformities is effective at correcting malalignment and avoiding graft failure out to 2 years. This procedure also holds promise to allow a majority of patients to return to various levels of sporting activities. To our knowledge, this is the first comparative study comparing the intermediate outcomes of this subpopulation to a matched revision ACL cohort. While these data do provide evidence for ongoing investigation, it is important to note that this pilot study is underpowered and we strongly recommend the performance of larger clinical trials to confirm these results. [Table: see text][Table: see text]

Association of Tibial Tubercle–Trochlear Groove Distance With Risk of ACL Graft Failure

Background: Limited evidence suggests a positive correlation between tibial tubercle–trochlear groove (TT-TG) distance and the risk of native anterior cruciate ligament (ACL) tear. The relationship between TT-TG distance and the risk of ACL graft failure is unknown. Hypothesis: TT-TG distance is independently associated with risk of ACL graft failure. Study Design: Cohort study; Level of evidence, 3. Methods: All patients who underwent ACL revision surgery between 2010 and 2018 at a single institution were identified. A control cohort underwent primary ACL reconstruction (ACLR) between 2006 and 2015, with no evidence of graft failure at 8.1 ± 2.5 years postoperatively. Record review included anthropometrics, graft type, and estimated Tegner activity score at ≥6 months after primary ACLR. Magnetic resonance imaging (MRI) scans after native ACL tear (controls) or graft failure (revision cohort) were assessed for (1) TT-TG distance, (2) proximal tibial slopes, (3) depth of tibial plateau concavity, and (4) tunnel position (revision cohort). Associations between ACL graft failure and MRI measurements, surgical variables, and patient characteristics were evaluated with logistic regression analyses. Sensitivity analyses, excluding patients with tunnel malposition, were performed to confirm multivariable results in patients with “ideal” tunnel placement. Results: Participants included 153 patients who underwent revisions and 144 controls. Controls were older than the patients who underwent revision (26.6 ± 8.8 vs 20.6 ± 7.3 years; P &lt; .001). The mean TT-TG distance and lateral posterior tibial slope (PTS) were smaller for the control group than for the revision group (TT-TG: 9.3 ± 3.9 vs 11.2 ± 4.2 mm; P &lt; .001; lateral PTS: 6.2° ± 3.3° vs 7.2° ± 3.6°; P = .01). TT-TG distance, lateral PTS, and age were associated with risk of ACL graft failure by multivariable analysis (OR, 1.15; 95% CI, 1.07-1.23; P &lt; .001; OR, 1.13; 95% CI, 1.04-1.22; P = .004; and OR, 0.90; 95% CI, 0.87-0.94; P &lt; .001, respectively). With sensitivity analyses, TT-TG distance, lateral PTS, and age at index surgery remained significantly and independently associated with ACL graft failure. Conclusion: Increased TT-TG distance, increased lateral PTS, and younger age are independently associated with increased odds of ACL graft failure. Patients with these characteristics may require a more comprehensive strategy to reduce the risk of ACL reinjury.

Management of anterior cruciate ligament revision in adults: the 2022 ESSKA consensus part III-indications for different clinical scenarios using the RAND/UCLA appropriateness method.

The aim of the ESSKA 2022 consensus Part III was to develop patient-focused, contemporary, evidence-based, guidelines on the indications for revision anterior cruciate ligament surgery (ACLRev). The RAND/UCLA Appropriateness Method (RAM) was used to provide recommendations on the appropriateness of surgical treatment versus conservative treatment in different clinical scenarios based on current scientific evidence in conjunction with expert opinion. A core panel defined the clinical scenarios with a moderator and then guided a panel of 17 voting experts through the RAM tasks. Through a two-step voting process, the panel established a consensus as to the appropriateness of ACLRev for each scenario based on a nine-point Likert scale (in which a score in the range 1-3 was considered 'inappropriate', 4-6 'uncertain', and 7-9 'appropriate'). The criteria used to define the scenarios were: age (18-35years vs 36-50years vs 51-60years), sports activity and expectation (Tegner 0-3 vs 4-6 vs 7-10), instability symptoms (yes vs no), meniscus status (functional vs repairable vs non-functional meniscus), and osteoarthritis (OA) (Kellgren-Lawrence [KL] grade 0-I-II vs grade III). Based on these variables, a set of 108 clinical scenarios was developed. ACLRev was considered appropriate in 58%, inappropriate in 12% (meaning conservative treatment is indicated), and uncertain in 30%. Experts considered ACLRev appropriate for patients with instability symptoms, aged ≤ 50years, regardless of sports activity level, meniscus status, and OA grade. Results were much more controversial in patients without instability symptoms, while higher inappropriateness was related to scenarios with older age (51-60years), low sporting expectation, non-functional meniscus, and knee OA (KL III). This expert consensus establishes guidelines as to the appropriateness of ACLRev based on defined criteria and provides a useful reference for clinical practice in determining treatment indications. II.

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

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. All cases of multiple ACL revisions performed with allograft tissue at one single sport-medicine institution were extracted and patients with a minimum 2years 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. 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). 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. III.

Meniscal and Articular Cartilage Predictors of Outcome After Revision ACL Reconstruction: A 6-Year Follow-up Cohort Study

Background: Meniscal and chondral damage is common in the patient undergoing revision anterior cruciate ligament (ACL) reconstruction. Purpose: To determine if meniscal and/or articular cartilage pathology at the time of revision ACL surgery significantly influences a patient’s outcome at 6-year follow-up. Study Design: Cohort study; Level of evidence, 3. Methods: Patients undergoing revision ACL reconstruction were prospectively enrolled between 2006 and 2011. Data collection included baseline demographics, surgical technique, pathology, treatment, and scores from 4 validated patient-reported outcome instruments: International Knee Documentation Committee (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Marx Activity Rating Scale. Patients were followed up at 6 years and asked to complete the identical set of outcome instruments. Regression analysis assessed the meniscal and articular cartilage pathology risk factors for clinical outcomes 6 years after revision ACL reconstruction. Results: An overall 1234 patients were enrolled (716 males, 58%; median age, 26 years). Surgeons reported the pathology at the time of revision surgery in the medial meniscus (45%), lateral meniscus (36%), medial femoral condyle (43%), lateral femoral condyle (29%), medial tibial plateau (11%), lateral tibial plateau (17%), patella (30%), and trochlea (21%). Six-year follow-up was obtained on 79% of the sample (980/1234). Meniscal pathology and articular cartilage pathology (medial femoral condyle, lateral femoral condyle, lateral tibial plateau, trochlea, and patella) were significant drivers of poorer patient-reported outcomes at 6 years (IKDC, KOOS, WOMAC, and Marx). The most consistent factors driving outcomes were having a medial meniscal excision (either before or at the time of revision surgery) and patellofemoral articular cartilage pathology. Six-year Marx activity levels were negatively affected by having either a repair/excision of the medial meniscus (odds ratio range, 1.45-1.72; P≤ .04) or grade 3-4 patellar chondrosis (odds ratio, 1.72; P = .04). Meniscal pathology occurring before the index revision surgery negatively affected scores on all KOOS subscales except for sports/recreation (P < .05). Articular cartilage pathology significantly impaired all KOOS subscale scores (P < .05). Lower baseline outcome scores, higher body mass index, being a smoker, and incurring subsequent surgery all significantly increased the odds of reporting poorer clinical outcomes at 6 years. Conclusion: Meniscal and chondral pathology at the time of revision ACL reconstruction has continued significant detrimental effects on patient-reported outcomes at 6 years after revision surgery.

High prevalence of increased posterior tibial slope in ACL revision surgery demands a patient-specific approach.

To determine the prevalence of an "increased posterior tibial slope (PTS)" (PTS ≥ 12°) in a population with one, two or ≥ three anterior cruciate ligament (ACL) graft insufficiencies. Furthermore, to investigate whether the prevalence of an increased PTS and the absolute PTS increases with an increasing number of ACL graft insufficiencies, as well as to determine the survival time of the first ACL graft. Patients diagnosed with an ACL graft insufficiency between January 2021 and March 2022 were included. The PTS was measured using the proximal anatomical tibial axis on long lateral knee radiographs. Patients were divided into 3 groups depending on the number of ACL graft insufficiencies: group A (1 graft insufficiency), group B (2 graft insufficiencies) and group C (≥ 3 graft insufficiencies). The prevalence of increased PTS and absolute PTS between groups was compared alongside the survival of the first ACL graft between patients with or without increased PTS. Two-hundred and six patients (147 males/59 females) met the inclusion criteria. 73 patients showed an increased PTS [prevalence 35% [95% confidence interval (CI) (29%; 42%)]. 155 patients were found in category A, 42 patients in B and 9 patients in C. The prevalence of increased PTS for group A, B and C was, 32% [95% CI (25%; 40%)], 38% [95% CI (23%; 53%)] and 78% [95% CI (51%; 100%)], respectively. The prevalence of increased PTS and mean PTS did not increase significantly between group A and B. However, both parameters increased significantly between group A and C, and group B and C (p < 0.05). The survival time of the first ACL graft in patients with or without an increased PTS was 3 (interquartile range (IQR) 5) and 6years (IQR 9), respectively (p < 0.05). There is a 35% prevalence of increased PTS in the studied ACL graft insufficient patient cohort. The survival of the first ACL graft is shorter in patients with an increased PTS. Surgeons should be aware of the high prevalence of increased PTS when consulting patients for revision ACL reconstruction as it is an important risk factor for recurrent instability.

Massive foreign body reaction and osteolysis following primary anterior cruciate ligament reconstruction with the ligament augmentation and reconstruction system (LARS): a case report with histopathological and physicochemical analysis

BackgroundAutologous hamstrings and patellar tendon have historically been considered the gold standard grafts for anterior cruciate ligament reconstruction (ACLR). In the last decades, the utilization of synthetic grafts has re-emerged due to advantageous lack of donor site morbidity and more rapid return to sport. The Ligament Augmentation and Reconstruction System (LARS) has demonstrated to be a valid and safe option for ACLR in the short term. However, recent studies have pointed out the notable frequency of associated complications, including synovitis, mechanical failure, and even chondrolysis requiring joint replacement.Case presentationWe report the case of a 23-year-old male who developed a serious foreign body reaction with wide osteolysis of both femoral and tibial tunnels following ACLR with LARS. During first-stage arthroscopy, we performed a debridement of the pseudocystic mass incorporating the anterior cruciate ligament (ACL) and extending towards the tunnels, which were filled with autologous anterior iliac crest bone graft chips. Histological analysis revealed the presence of chronic inflammation, fibrosis, and foreign body giant cells with synthetic fiber inclusions. Furthermore, physicochemical analysis showed signs of fiber depolymerization, increased crystallinity and formation of lipid peroxidation-derived aldehydes, which indicate mechanical aging and instability of the graft. After 8 months, revision surgery was performed and ACL revision surgery with autologous hamstrings was successfully carried out.ConclusionsThe use of the LARS grafts for ACLR should be cautiously contemplated considering the high risk of complications and early failure.

In slope-changing osteotomy one millimeter is not one degree: results of an artificial intelligence-automated software analysis.

Anterior closing wedge osteotomies (ACWO) are performed in revision anterior cruciate ligament (ACL) surgery to correct an excessive posterior tibial slope (PTS). With the help of automated planning software, this study investigates the assumption that 1mm of wedge height gives 1° of slope correction (1:1). Fifty patients underwent ACWO, with the wedge height calculated using the 1:1 formula. Pre- and postosteotomy PTS were measured manually, and the achieved post-operative PTS was compared with the target PTS of 5.3° ± 1.9. The X-ray analysis was repeated virtually with the automated software, which also recommended a resection height. These parameters were then compared with the manually obtained parameters. Using a 1:1 formula, wedge heights of 8.5mm ± 2.3 was resected to achieve a PTS of 4.2° ± 0.32. This showed an overcorrection of 1.6° ± 0.8 from the target slope. This was consistent with the data from the automated software, which recommended a lower wedge height of 7.7mm ± 2.9. In trans-tubercle ACW, using a wedge height (mm) to slope correction (°) ratio of 1:1 can lead to slight over-correction. Automated software planning is useful for planning correction osteotomies in the sagittal plane.