Preservation Of Anterior Cruciate Ligament Research Articles

Anatomic Arthroscopic Primary Repair of Proximal Anterior Cruciate Ligament Tears

Within the last decade, various highly diverse anterior cruciate ligament (ACL) preservation techniques have been proposed, as contemporary selective arthroscopic ACL preservation experienced a resurgence. Among surgical techniques, there are a variety of suturing, fixation, and augmentation methods, whereas a common thread, considering essential anatomic and biomechanical properties, is missing. This technique aims to anatomically reapproximate both the anteromedial (AM) and posterolateral (PL) bundles to their respective femoral footprints. Additionally, a PL compression stitch is performed to increase the ligament-bone contact area and recreate the anatomic vectors of the native bundles, therefore, creating a more anatomic and biomechanical construct. This technique is a minimally invasive procedure, with no graft harvesting nor tunnel drilling, which leads to decreased pain levels, earlier return of full range motion (ROM), and faster rehabilitation, while failure rates seem to be comparable to that of ACL reconstruction. We present an updated surgical technique of anatomic arthroscopic primary repair with suture anchor fixation for patients with proximal ACL tears.

Bicruciate-retaining total knee arthroplasty: What’s new?

Primary total knee arthroplasty (TKA) is a widespread procedure to address end stage osteoarthritis with good results, clinical outcomes, and long-term survivorship. Although it is frequently performed in elderly, an increased demand in young and active people is expected in the next years. However, a considerable dissatisfaction rate has been reported by highly demanding patients due to the intrinsic limitations provided by the TKA. Bicruciate-retaining (BCR) TKA was developed to mimic knee biomechanics, through anterior cruciate ligament preservation. First-generation BCR TKA has not gained popularity due to its being a challenging technique and having poor survival outcomes. Thanks to implant design improvement and surgeon-friendly instrumentation, second-generation BCR TKA has seen renewed interest. This review will focus on surgical indications, kinematical basis, clinical results and latest developments of second-generation BCR TKA.

Combined ACL and Segond Repair in Combined Acute Proximal ACL Tears and Segond Fracture

AbstractA renewed interest in anterior cruciate ligament preservation has been noted using arthroscopic primary repair in patients with proximal tears, but the main concern remained the control of the rotational instability. Segond fracture occurs in less than 10% of cases of acute anterolateral instability, but it can result in continued rotation instability. The aim of this study is to describe the surgical technique to acutely repair both the anterior cruciate ligament and Segond fracture in the acute setting.

Anterior cruciate ligament tear patterns in young patients: An arthroscopic multicenter study

IntroductionIn the last decade, there has been a renewed interest in anterior cruciate ligament (ACL) preservation surgeries in the younger patients. Several ACL preservation techniques such as primary repair, augmented repair, and scaffold repair have been described based on the particular tear type and pattern. The purpose of this study was to determine the distribution of tear patterns in young patients presenting with an acute ACL injury. MethodsA prospective observational study was performed at two tertiary children’s hospitals. Patients under 18 years undergoing ACL reconstruction within 8 weeks of initial injury were included from 2017 to 2019. Tear patterns were classified by two orthopedic surgeons from each of the two centers during arthroscopic ACL reconstruction into 4 types: I. Avulsion off the femur, II. <10% of total ACL length tear from femoral end, III. Mid-substance tear and IV. Single bundle tear. For reliability, the four surgeons classified ACL injury (2 rounds each) based on de-identified intraoperative videos of 33 randomly selected surgical ACL cases. Inter and intra-rater reliability studies were calculated using Kappa statistics. Results224 patients (123 males, 101 females) with mean age of 16 (range: 9–18) years were enrolled in this study. Fifty-seven (25%) patients reported contact injury while 167 (75%) reported non-contact. Isolated ACL injury was recorded in 70 (31%) patients, while concomitant injuries were recorded in 154 patients (69%). The most common associated injury was lateral meniscus tear (35%), followed by lateral and medial meniscus tears (20%). According to our classification, 31 (14%) patients were Type I, 30 (13%) were Type II, 139 (62%) were Type III, 18 (8%) were Type IV. The intra-rater reliability was excellent for 2 reviewers, good for 1 and marginal for another. The overall inter-rater reliability for all 4 reviewers was marginal for both readings. There was no statistical difference in the occurrence of type of tear based on the mechanism of injury (contact vs non-contact) or age of the patients. ConclusionsThis is the first multicenter study using an arthroscopic assessment to classify the location of ACL tear in the young population. It gives us further insight on the possible application for surgeries to preserve the ACL in this group. Larger studies incorporating these findings with MRI evaluation and ACL repair techniques are needed to confirm the utility of this information to decide the eligibility for repair in pediatric patients.

Leveraging subject-specific musculoskeletal modeling to assess effect of anterior cruciate ligament retaining total knee arthroplasty during walking gait.

Bi-cruciate retaining total knee arthroplasty has several potential advantages including improved anteroposterior knee stability compared to contemporary posterior cruciate-retaining total knee arthroplasty. However, few studies have explored whether there is significant differences of knee biomechanics following bi-cruciate retaining total knee arthroplasty compared to posterior cruciate-retaining total knee arthroplasty. In the present study, subject-specific lower extremity musculoskeletal multi-body dynamics models for bi-cruciate retaining, bi-cruciate retaining without anterior cruciate ligament, and posterior cruciate-retaining total knee arthroplasty were developed based on the musculoskeletal modeling framework using force-dependent kinematics method and validated against in vivo telemetric data. The experiment data of two subjects who underwent total knee arthroplasty were obtained for the SimTK "Grand Challenge Competition" repository, and integrated into the musculoskeletal model. Five walking gait trials for each subject were used as partial inputs for the model to predict the knee biomechanics for bi-cruciate retaining, bi-cruciate retaining without anterior cruciate ligament, and posterior cruciate-retaining total knee arthroplasty. The results revealed significantly greater range of anterior/posterior tibiofemoral translation, and significantly more posterior tibial location during the early phase of gait and more anterior tibial location during the late phase of gait were found in bi-cruciate retaining total knee arthroplasty without anterior cruciate ligament when compared to the bi-cruciate retaining total knee arthroplasty. No significant differences in tibiofemoral contact forces, rotations, translations, and ligament forces between bi-cruciate retaining and posterior cruciate-retaining total knee arthroplasty during normal walking gait, albeit slight differences in range of tibiofemoral internal/external rotation and anterior/posterior translation were observed. The present study revealed that anterior cruciate ligament retention has a positive effect on restoring normal knee kinematics in bi-cruciate retaining total knee arthroplasty. Preservation of anterior cruciate ligament in total knee arthroplasty and knee implant designs interplay each other and both contribute to restoring normal knee kinematics in different types of total knee arthroplasty. Further evaluation of more demanding activities and subject data from patients with bi-cruciate retaining and posterior cruciate-retaining total knee arthroplasty via musculoskeletal modeling may better highlight the role of the anterior cruciate ligament and its stabilizing influence.

The Reliability of Classifying the Morphology of Anterior Cruciate Ligament Remnants during Surgery.

Arthroscopic classification of the torn anterior cruciate ligament (ACL) morphology is fundamental for clinical studies on emerging techniques such as repair and preservation. At present, the most acknowledged classification is Crain description of four morphological patterns. The purpose of the study was to analyze the intra- and interobserver reliability of Crain classification in patients undergoing ACL reconstruction surgeries. The study included 101 patients who had ACL reconstruction surgery between the years 2014 and 2017. The morphological pattern of ACL remnant scar formation during surgery was observed and classified according to Crain by three orthopaedic surgeons. Inter- and intraobserver reliabilities were measured using kappa statistics. Intraobserver reliability for the Crain classification ranged from 0.63 to 0.83 (substantial to almost perfect agreement). Interobserver reliability was 0.51 (moderate agreement). In almost a third of the cases, observers reported on additional morphological pattern of scar formation that was not well defined by Crain. A modified classification of four patterns was suggested: (A) without scar tissue, (B) with adhesion to the femoral notch (wall or roof), (C) with adhesion to the notch and posterior cruciate ligament (PCL), and (D) with adhesion to the PCL. Reanalysis of these four morphological configurations resulted in interobserver reliability of 0.82 (almost perfect agreement). In conclusion, the Crain classification of torn ACL remnant morphology has moderate interobserver reliability; however, a suggested classification with modified and additional configurations has almost perfect reliability and may be useful for studies on ACL repair and preservation.

Approximately 30% of Functioning Anterior Cruciate Ligaments Are Sacrificed for Knee Arthroplasty.

The anterior cruciate ligament (ACL) plays an important role in knee kinematics. Unicompartmental knee arthroplasty (UKA) preserves the ACL, an advantage over total knee arthroplasty (TKA), where it is sacrificed. This study aims to evaluate how often functional ACLs are sacrificed in arthroplasty. The type of arthroplasty (TKA or UKA) and condition of the ACL were studied in a total of 1,586 knees in 1,052 patients who underwent knee arthroplasties. Of 1,586 knees, TKA was performed on 653 knees (41%) and UKA on 933 knees (59%). The ACL was functioning in 77% of all knees. Of the TKA knees, the ACL was functioning in 357 knees (55%). Of these, around 30% of the functioning ACLs were sacrificed to perform TKA. To improve postoperative patient satisfaction after knee arthroplasty, further study regarding relationship between ACL preservation and clinical outcome will be required.

Management of Anterior Cruciate Ligament Injury: What's In and What's Out?

Sports medicine physicians have a keen clinical and research interest in the anterior cruciate ligament (ACL). The biomechanical, biologic, and clinical data researchers generate, help drive injury management and prevention practices globally. The current concepts in ACL injury and surgery are being shaped by technological advances, expansion in basic science research, resurging interest in ACL preservation, and expanding efforts regarding injury prevention. As new methods are being developed in this field, the primary goal of safely improving patient outcomes will be a unifying principle. With this review, we provide an overview of topics currently in controversy or debate, and we identify paradigm shifts in the understanding, management, and prevention of ACL tears.

The Locations of Anterior Cruciate Ligament Tears in Pediatric and Adolescent Patients: A Magnetic Resonance Study.

Recently, a resurgence of interest has been noted in anterior cruciate ligament (ACL) preservation in pediatric and adolescent patients. Different tear types, defined by their tear location, require different preservation techniques: proximal and distal avulsion tears can be treated with arthroscopic primary repair, whereas primary repair with biological scaffold has been proposed for midsubstance tears. The goal of this study was to assess the distribution of different tear types in pediatric and adolescent patients, as these are currently unknown. A retrospective search in an institutional radiographic database was performed for patients under 18.0 years undergoing knee magnetic resonance imaging (MRI) for ACL tears between June 2005 and June 2016. Patients with reports of chronic tears, partial tears, and multiligamentous injuries were excluded.Tear locations were graded using MRI as: proximal avulsion (distal remnant length >90% of total length; type I), proximal (75% to 90%; type II), midsubstance (25% to 75%; type III), distal (10% to 25%; type IV), and distal avulsion (<10%; type V). A total of 274 patients (59% girls; mean±SD age, 15.1±2.1 y; range, 6.9 to 18.0 y) were included. Frequency of type I tears was 15%, type II 23%, type III 52%, type IV 1%, and type V 8% (of which 7% had bony avulsion).Prevalence of tear types varied with age. At age 6 to 10 years, 93% were type V (bony) avulsion tears. At age 11 to 13 years, 32% were type I, 16% type II, 32% type III, and 16% type V. At age 14 to 17 years, type III tears were more common (57%) than type I (14%), type II (25%) and type V (2%) tears. It was noted that the ACL was torn at different locations depending on the patients' age. These data provide more information on the potential application for ACL preservation in pediatric and adolescent patients. Future studies correlating these findings with arthroscopy are needed before using MRI for preoperative planning of ACL preservation surgery. Diagnostic level III.

The Location of Anterior Cruciate Ligament Tears: A Prevalence Study Using Magnetic Resonance Imaging.

Background:Over the past decade, there has been a resurgence of interest in anterior cruciate ligament (ACL) preservation. Proximal and distal avulsion tears have been treated with arthroscopic primary repair, while augmented repair, remnant tensioning, primary repair with biological scaffold, and remnant preservation have been proposed for different types of midsubstance tears. Currently, the incidence of these different tear types is unknown.Purpose:To propose a magnetic resonance imaging (MRI) classification system for different tear types based on clinical relevance and to assess the distribution of these different ACL tear types.Study Design:Case series; Level of evidence, 4.Methods:A retrospective search in an institutional radiographic database was performed for patients who underwent knee MRI at our institution between June 2014 and June 2016. Patients younger than 18 years and those with reports of chronic tears, partial tears, multiligamentous injuries, were excluded. Tear types were graded as proximal avulsion (distal remnant length >90% of total ligament length, type I), proximal (75%-90%, type II), midsubstance (25%-75%, type III), distal (10%-25%, type IV), and distal avulsion (<10%, type V). An orthopaedic surgeon, a radiologist, and a research fellow graded the tear type on 30 MRIs to determine reliability, and the research fellow graded all MRIs. Inter- and intraobserver reliability were measured using kappa statistics.Results:A total of 353 patients (57% male; mean age, 37.1 years; range, 18.1-81.2 years) were included. Interobserver reliability was 0.670 (95% confidence interval, 0.505-0.836), and intraobserver reliability ranged from 0.741 to 0.934. Incidence of type I tears was 16%, type II tears 27%, type III tears 52%, type IV tears 1%, and type V tears 3% (2.5% with bony avulsion). Type I tears were more common in patients older than 35 years compared with those younger than 35 years (23% vs 8%; P < .001).Conclusion:This classification system was reliable in assessing tear location in acute ACL injuries. Type I tears were seen in 16%, type II in 27%, and type III in 52% of patients in our cohort. These data suggest that there may be greater potential application for ACL preservation techniques.

Is anterior cruciate ligament preservation surgery better than reconstructing both bundles?

Rupture of the anterior cruciate ligament (ACL) is one of the most common ligamentous injuries of the knee, with an incidence of 35 out of 100,000. An ACL reconstruction is now a routine procedure. Generally, good outcomes are expected from the surgery, with return to preinjury level of sports activity in most patients. Debate, however, continues regarding the advantages of preserving the ACL remnant and augmenting it with a graft as opposed to debridement of the remnant in a standard ACL reconstruction. The purpose of this article is to consider the scientific basis of ACL preservation surgery (remnant preservation and selective bundle reconstruction) and to compare the outcomes between an ACL-preserving surgery and a double-bundle reconstruction. Both techniques provide anteroposterior laxity control and some degree of control on rotational laxity. Although superior Lysholm and subjective International Knee Documentation Committee (IKDC) scores have been documented with double-bundle reconstructions, remnant-preserving procedures have several advantages and seem to have a valuable contribution either on single-bundle, selective, and double-bundle reconstructions. Based on our experience, we recommend the remnant preserving technique. However, longer follow-up is necessary to ascertain which procedure could restore the normal knee kinematics, thus providing better clinical outcomes.

Anterior Cruciate Ligament Preservation: Early Results of a Novel Arthroscopic Technique for Suture Anchor Primary Anterior Cruciate Ligament Repair

To propose a technique of arthroscopic suture anchor primary anterior cruciate ligament (ACL) preservation for patients with proximal avulsion ACL tears that maintain excellent tissue quality. We performed a retrospective review and early follow-up of 11 consecutive cases of ACL preservation. Patients were included if they had a proximal avulsion tear and excellent tissue quality confirmed to be adequate for repair during arthroscopy. Patients were excluded if these criteria were not met or if patients had multiligamentous injury patterns or significant arthrosis. The ACL was reinforced with a No. 2 FiberWire (Arthrex, Naples, FL) and a No. 2 TigerWire (Arthrex) and was anchored to the femoral footprint by two 4.75-mm BioComposite SwiveLock suture anchors (Arthrex). The surgical procedures were performed at 3 different hospitals by a single surgeon. Anterior stability was determined with a KT-1000 arthrometer (MEDmetric, San Diego, CA). Clinical outcomes were measured using the Lysholm score, modified Cincinnati score, Tegner activity score, Single Assessment Numeric Evaluation, and subjective and objective International Knee Documentation Committee (IKDC) scores. Ten of eleven patients had good subjective and clinical outcomes after ACL preservation surgery at a minimum of 2years' and mean of 3.5years' follow-up. The mean Lysholm score was 93.2; the mean modified Cincinnati score was 91.5; the preoperative Tegner activity score was maintained postoperatively in 8 of 10 patients; the mean Single Assessment Numeric Evaluation score was 91.5; the mean subjective IKDC score was 86.4; and the objective IKDC score was A in 9 of 11 patients, B in 1 patient, and C in 1 patient. KT-1000 measurements were available in 8 of 11 patients, with 7 of 8 showing a side-to-side difference of less than 3mm on maximum manual testing and 1 showing a 6-mm difference. Preservation of the native ACL using the described arthroscopic primary repair technique can achieve short-term clinical success in a carefully selected subset of patients with proximal avulsion-type tears and excellent tissue quality. Level IV, therapeutic case series.

How Useful Is MRI in Diagnosing Isolated Bundle ACL Injuries?

Selective bundle anterior cruciate ligament (ACL) reconstruction and/or remnant ACL preservation may be reasonable options for some patients. However, the frequency of isolated anteromedial (AM) or posterolateral (PL) bundle injuries in patients undergoing ACL reconstruction is unknown, and the value of MRI for prediction of this injury pattern is likewise unknown. We sought to determine (1) the proportion of knees with an intact AM or PL bundle in patients undergoing ACL reconstruction; (2) whether MRI predicted the bundle conditions seen at the time of surgery; and (3) whether the accuracy of the MRI prediction was affected by the timing of MRI after injury. During primary ACL reconstructions of 156 knees, conditions of AM and PL bundles were separately examined and classified into three categories: (1) completely torn; (2) attenuated; and (3) intact. Then, the bundles were assessed by blinded observers on MRI and classified into the corresponding three categories for 77 patients who had an MRI at our institution using a standard protocol. Diagnostic accuracy of MRI was computed, and the early MRI group (≤6 weeks from injury to MRI acquisition) was compared with the late MRI group (>6 weeks). Only 11 (7%) of the 156 knees we treated had an intact AM (one knee) or PL bundle (10 knees). Another 55 knees (35%) had a structurally continuous but attenuated AM or PL bundle. The overall diagnostic accuracy of MRI was 83%; accuracy was better for the AM bundle than the PL bundle (91% versus 78%; p=0.026). MR prediction was less accurate in the early MRI group, particularly for PL bundle injury. An isolated bundle tear is uncommon in patients with ACL tears undergoing reconstruction. MRI can help surgeons predict bundle injury pattern with satisfactory precision, but caution should be used in predicting PL bundle injury using MRI with early acquisition time from injury. Level III, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Anterior Cruciate Ligament preservation during reconstructive surgery: Does the extra surgical effort improve patient outcomes at one year?

BackgroundThe aim of this prospective cohort study was to compare patient-reported and clinical outcomes at one year post-operatively in patients who had a standard quadruple stranded hamstring tendon anterior cruciate ligament (ACL) reconstruction to those who had ACL tissue preservation with a double semitendinosus reconstruction. Materials and MethodsForty-five patients were selected for ACL preservation surgery (ACL Preserved group) and were matched by age, sex and injury acuity to 45 patients who had a standard reconstruction (ACL Reconstructed group). The primary outcome was the validated ACL-QOL score. Secondary outcomes included the IKDC Subjective and Objective assessments, clinical and instrumented laxity testing, and Tegner Activity Level. All outcomes were measured at baseline and at a minimum of one year post-operatively, by an independent qualified assessor. ResultsThe two patient groups were similar for all baseline characteristics except for a larger number of meniscal pathology in the ACL Reconstructed group. Both groups had statistically significant and clinically important improvement from baseline to one year. The ACL Preserved group showed better results for all outcomes. The ACL-QOL change score from baseline was 8.6 points (p=0.04) higher for the ACL Preserved compared to the ACL Reconstructed group. KT-2000 measurements showed a statistically significant side-to-side difference between groups. The IKDC Objective assessment reported 87% of patients with normal/nearly normal knees in the ACL Preserved group compared to 80% in the ACL Reconstructed group. ConclusionsIn patients where it is possible and feasible to preserve ACL tissue, this study suggests that the more technically demanding procedure involving ACL preservation during reconstructive surgery is worth the extra effort. The procedure provides a consistent and measurable benefit in terms of knee stability and quality of life at one year post-operative, compared to a standard hamstring reconstruction. Level of evidenceTherapeutic, prospective cohort study; Level II.

Partial ACL reconstruction with preservation of the posterolateral bundle

Over the past decade, our understanding of the anterior cruciate ligament (ACL) has evolved considerably. Based on this knowledge, ACL reconstruction techniques have changed and selective reconstruction procedures have been developed for partial tears. Our hypothesis was that stability and function can be restored to the knee with selective bundle reconstruction of partial ACL tears and preservation of the residual fibers. This was a multicenter retrospective study of 168 partial reconstructions of the anteromedial (AM) bundle of the ACL with preservation of the posterolateral (PL) bundle. All patients underwent a clinical evaluation based on the objective and subjective IKDC scores and the Lysholm score after a mean follow-up of 26 months (12-59 months). Preoperative and postoperative instrumental measurement of knee laxity was performed by arthrometer and/or by (Telos(®)) stress radiography. Statistical analysis and comparison was performed between pre- and postoperative results. The preoperative and postoperative subjective IKDC scores were 63.7 and 90.5 at the final follow-up respectively (P<0.001). The preoperative and postoperative Lysholm scores were 80 and 95.5 respectively (P<0.001). Preoperatively, most patients were classified C on the objective IKDC score. At the final follow-up 92% of the patients were classified A or B (P<0.001). Differential preoperative laxity was 5.5mm (range: 0-14 mm) and 1.1mm (range: 0-4mm) at the final follow-up (P<0.00001). Our study confirms that selective reconstruction of the AM bundle of the ACL with preservation of the PL bundle restores stability and function to the knee. Special attention should be paid to the size of the graft used to avoid excess tissue in the intercondylar notch.

Arthroscopic treatment for tibial “Peel off” tears in anterior cruciate ligament-case report

Anterior cruciate ligament (ACL) injury was very common, and its reconstruction is one of the most commonly performed orthopaedic surgeries. A standard treatment option for ACL complete rupture in active young patients is debridement of remnant tissue and reconstruction with various types of tendon graft. However, "A tibial peel off tear" of ACL without bony avulsion can be treated using preservation of original ACL and trans-osseous pullout suture repair. The IKDC subjective score was 90, the objective score was A, and the Lysholm score was 95 at 24 months after surgery. KT-2000 arthrometer showed 2 mm side-to-side difference. Pivot shift test and Lachman test were negative, and there was no limitation in range of motion. Patient returned to full activities including sports and satisfied with the surgical results. In the postoperative MRI at 6 months after the surgery, the continuity of ACL was well maintained without any Cyclops lesion. We believe that trans-osseous pullout suture repair could be included as an alternative method in this "tibial peel off" type ACL injury instead of the usual removal of remnant tissue and reconstruction with a graft.