Anterior Cruciate Ligament Graft Fixation Research Articles

The Effect of Supplementary Staple Fixation on Biomechanical Properties of Soft Tissue Graft Tibial Fixation in Anterior Cruciate Ligament Reconstruction.

This study aimed to test and compare the biomechanical properties of three tibial fixation methods of anterior cruciate ligament (ACL) tendon grafts under cyclic load and load-to-failure testing in the bovine proximal tibiae, comprising (1) staple fixation alone, (2) interference screw fixation alone, and (3) interference screw fixation with a supplementary staple. Twenty-four bovine tibiae used in the study were divided into three groups (eight proximal tibiae in each group) based on tibial fixation methods of ACL tendon grafts: group A (a spiked ligament staple alone), group B (a cannulated interference screw alone), and group C (a cannulated interference screw with a supplementary staple). Each graft fixation was exposed to cyclic loading conditions. Significant differences were determined in failure load among the three groups (p = 0.008). The mean failure load was significantly higher in group B (717.04 ± 218.51 N) than in group A (308.03 ± 17.22 N) (p = 0.006). No significant differences were observed among the groups regarding axial stiffness (p = 0.442). Cyclic displacement differed significantly among the three groups (p = 0.005). In pairwise comparisons, the mean cyclic displacement was significantly higher in group A (8.22 ± 3.24 mm) compared with group C (1.49 ± 0.41 mm) (p = 0.005). Failure displacement varied considerably among the groups (p = 0.037). Although group B (15.53 ± 6.43 mm) exhibited a greater mean failure displacement than both group A (4.9 ± 0.75 mm) and group C (8.84 ± 4.65 mm), these differences did not reach statistical significance (p = 0.602 and p = 0.329, respectively). Interference screw fixation alone and supplementary staple fixation have biomechanically similar characteristics in terms of initial strength and stiffness of tibial ACL soft tissue graft fixation. Regardless of staple use, an interference screw with the same diameter as the tibial tunnel can ensure sufficient tensile strength in tibial ACL graft fixation.

Hybrid Press-fit and Adjustable Button Femoral Fixation of Anterior Cruciate Ligament Semitendinosus and Bone-patellar Tendon-bone Autografts—A Technical Note

Introduction: Many fixation methods are available for anterior cruciate ligament (ACL) grafts. Adjustable buttons (ABs) are characterized by their high fixation strength but have the disadvantage of potential stretching of their linking suture material. Press-fit bone plugs provide fixation at the joint line and enhance biological graft healing. Using both is thought to result in a higher fixation strength, enhancing graft biology and transferring the fixation point to the joint line. Materials and Methods: It is the aim of this technical note to describe a certain technique of ACL graft hybrid fixation for hamstrings or bone-tendon-bone grafts, using AB combined with bone grafting of the femoral and tibial tunnels with press-fit bone plugs or bone chips. Discussion: ABs are commonly used fixation devices for ACL grafts. AB also allows the surgeon to tighten the ACL graft in full or near full extension. The ultimate load to failure of AB has the potential disadvantage of rendering the ACL graft progressively slack. AB augmented with press-fitting bone plugs enhances biological potentials, adds to fixation strength, and transfers the fixation level of the graft from the outer femoral cortex to the joint line. Conclusion: Hybrid AB and bone plug fixation of ACL autografts, whether hamstrings or bone-tendon bone, optimizes ACL graft fixation by gaining advantages and omitting the disadvantages of both techniques.

Triple Hybrid Tibial Anterior Cruciate Ligament Graft Fixation

Optimal graft fixation in anterior cruciate ligament reconstruction is critical. Several direct and indirect methods of graft fixation exist, each with advantages and disadvantages. This Technical Note describes a tibial hybrid anterior cruciate ligament graft fixation technique combining direct and indirect fixation methods, including autologous bone augmentation of the drill tunnel using cancellous bone fragments.

PEEK Interference Screws Show Significant Tunnel Enlargement After ACL Reconstruction and is Comparable to Adjustable-Length Loop Cortical Button Fixation

BackgroundIt is unclear whether the use of polyetheretherketone (PEEK) interference screws for anterior cruciate ligament (ACL) reconstruction leads to postoperative tunnel enlargement. Femoral tunnel enlargement was further compared with adjustable-length loop cortical fixation.MethodsEighteen patients with ACL reconstruction using hamstring grafts were retrospectively divided into two groups. Eleven patients were treated with the ACL reconstruction technique using a PEEK interference screw for femoral graft fixation. Seven patients received adjustable-length loop cortical buttons for femoral fixation. Tibial ACL graft fixation was performed using PEEK interference screws. Tunnel volume changes were assessed using computed tomography (CT) scans performed after surgery (100%) and after 1 year. The maximal tunnel diameter was measured.ResultsThe group with femoral screw fixation showed a mean tunnel volume change of 108.15 ± 13.7% on the tibial side and 124.07 ± 25.38% on the femoral side. The group with femoral button fixation showed a tunnel volume change of 111.12 ± 12.72% on the tibial side and 130.96 ± 21.71% on the femoral side. The differences in femoral tunnel volume changes were not significant (P = 0.562). Femoral tunnels with PEEK screw fixation showed significantly larger diameter after 12 months in comparison with button fixation (13.02 ± 1.43 mm vs. 10.46 ± 1.29 mm, P < 0.001).ConclusionsPEEK interference screws were associated with significant tibial and femoral tunnel enlargement. Femoral tunnel enlargement was comparable between PEEK interference screws and button fixation. Final femoral tunnel diameter was significantly larger with PEEK screw fixation in comparison to button fixation.

Interference screws manufactured from magnesium display similar primary stability for soft tissue anterior cruciate ligament graft fixation compared to a biocomposite material – a biomechanical study

PurposeBiodegradable interference screws (IFS) can be manufactured from different biomaterials. Magnesium was previously shown to possess osteoinductive properties, making it a promising material to promote graft-bone healing in anterior cruciate ligament reconstruction (ACLR). The purpose of this study was to compare IFS made from magnesium to a contemporary biocomposite IFS.MethodsIn a porcine model of ACL reconstruction, deep porcine flexor tendons were trimmed to a diameter of 8 mm, sutured in Krackow technique, and fixed with either 8 × 30 mm biocomposite IFS (Bc-IFS) or 8 × 30 mm magnesium IFS (Mg-IFS) in an 8 mm diameter bone tunnel in porcine tibiae. Cyclic loading for 1000 cycles from 0 to 250 N was applied, followed by load to failure testing. Elongation, load to failure and stiffness of the tested constructs was determined.ResultsAfter 1000 cycles at 250 N, elongation was 4.8 mm ± 1.5 in the Bc-IFS group, and 4.9 mm ± 1.5 in the Mg-IFS group. Load to failure was 649.5 N ± 174.3 in the Bc-IFS group, and 683.8 N ± 116.5 in the Mg-IFS group. Stiffness was 125.3 N/mm ± 21.9 in the Bc-IFS group, and 122.5 N/mm ± 20.3 in the Mg-IFS group. No significant differences regarding elongation, load to failure and stiffness between Bc-IFS and Mg-IFS were observed.ConclusionMagnesium IFS show comparable biomechanical primary stability in comparison to biocomposite IFS and may therefore be an alternative to contemporary biodegradable IFS.

Lateral Extra-Articular Tenodesis Staple Risks Penetration of Anterior Cruciate Ligament Reconstruction Tunnel

To identify the risk of anterior cruciate ligament (ACL) femoral tunnel penetration with the use of a staple for lateral extra-articular tenodesis (LET) graft fixation and to determine whether this varied between 2 different techniques for ACL femoral tunnel drilling. Twenty paired, fresh-frozen, cadaver knees underwent ACL reconstruction with a LET. Left and right knees were randomized to ACL reconstruction with femoral tunnel creation by use of either a rigid guide pin and reamer through the accessory anteromedial portal or by the use of a flexible guide pin and reamer through the anteromedial portal. Immediately after tunnel creation, the LET was performed and fixated with a small Richard's staple. Fluoroscopy was used to obtain a lateral view of the knee to determine staple position, and visualization of the ACL femoral tunnel was performed with the arthroscope to investigate penetration of the staple into the femoral tunnel. The Fisher exact test was conducted to determine whether there was any difference in tunnel penetration between tunnel creation techniques. The staple was noted to penetrate the ACL femoral tunnel in 8 of 20 (40%) extremities. When stratified by tunnel creation technique, the Richards staple violated 5 of 10 (50%) of the tunnels made via the rigid reaming technique compared with 3 of 10 (30%) of those created with a flexible guide pin and reamer (P= .65). A high incidence of femoral tunnel violation is seen with lateral extra-articular tenodesis staple fixation. Level IV, controlled laboratory study. The risk of penetrating the ACL femoral tunnel with a staple for LET graft fixation is not well understood. Yet, the integrity of the femoral tunnel is important for the success of ACL reconstruction. Surgeons can use the information in this study to consider adjustments to operative technique, sequence, or fixation devices used when performing ACL reconstruction with concomitant LET to avoid the potential for disruption of ACL graft fixation.

Effects of Initial Graft Tension and Patient Sex on Knee Osteoarthritis Outcomes After ACL Reconstruction: A Randomized Controlled Clinical Trial With 10- to 12-Year Follow-up

Background: The initial graft tension applied during anterior cruciate ligament (ACL) graft fixation may promote posttraumatic osteoarthritis (PTOA). Purpose/Hypothesis: This study sought to assess the effect of initial graft tension and patient sex on PTOA outcomes at 10 to 12 years after ACL reconstruction (ACLR). The hypothesis was that there would be no group- or sex-based differences in outcomes. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: Patients were randomized to receive ACLR with a low or high initial graft tension. Outcomes were evaluated at 10 to 12 years postoperatively and compared with a matched, uninjured control group. Outcomes included clinical assessments (anteroposterior [AP] knee laxity measurement, International Knee Documentation Committee [IKDC] examination score), a functional assessment (single-leg hop for distance), patient-reported outcomes (Knee injury and Osteoarthritis Outcome Score [KOOS], 36-Item Short Form Health Survey, Tegner activity level, patient satisfaction), and PTOA imaging (Osteoarthritis Research Society International [OARSI] radiographic score and Whole-Organ Magnetic Resonance Imaging Score [WORMS]). Two-way mixed-model analyses of variance were used to evaluate differences in outcomes between tension groups and the control group and between female and male patients. Results: Both tension groups scored worse than the control group for the IKDC examination (P≤ .021), KOOS (Pain, Activities of Daily Living, Sport/Recreation, and Quality of Life subscales) (P≤ .049), and WORMS difference score (P≤ .042). The low-tension group scored worse than the control group for KOOS Symptoms (P = .016) and the OARSI difference score (P = .015). The index limb had worse scores than the contralateral limb within the high-tension group for AP laxity (P = .030) and hop deficit (P = .011). This result was also observed within both tension groups for the WORMS (P≤ .050) and within the low-tension group for the OARSI score (P = .001). Male patients had higher Tegner scores (mean ± SE) relative to female patients (male, 5.49 ± 1.88; female, 4.45 ± 1.65) and worse OARSI difference scores (male, 1.89 ± 5.38; female, 0.244 ± 0.668) (P = .007 and .034, respectively). However, no significant differences were detected between tension groups for any of the outcomes measured. Conclusion: Overall, ACLR failed to prevent PTOA regardless of initial graft tension. However, male patients treated with a low initial graft tension may be at greater risk for PTOA. These results do not support the hypothesis of no sex differences in outcomes at 10 to 12 years after ACLR.

The Sironix ACL Jig: A Solution for Tibial Tunnel Angle and Length

Anterior cruciate ligament (ACL) reconstruction is widely performed arthroscopic procedures amongst sportspersons to prevent worsening of knee joint injury. The Sironix ACL jig is a novel approach to ensure an appropriate angle for accurate placement and drilling of tibial and femoral tunnels, that is a critical step for stronger and stable ACL graft fixation. It is designed as a patented jig with a three-point arm contact system. The three reference points serve as a continuous visual feedback on the angle of approach during surgery and minimize the parallax errors. Sironix ACL jig helps the orthopaedic surgeon in deciding the feasibility of a single bundle or double bundle ACL technique, facilitates varying technique choices for drilling, including inside-out and outside-in, accurately determines the tibial and femoral tunnel positioning in arthroscopic or open ACL reconstruction and therefore increases the procedural convenience.

Modern solutions in reconstruction of the anterior cruciate ligament

The rapid development of medical technologies makes the attitude to anterior cruciate ligament (ACL) reconstruction constantly reconsidered. In our work, we evaluated the results of surgical treatment of patients after ACL reconstruction using different options of graft fixation. We retrospectively analyzed the treatment of 125 patients with anterior instability of the knee joint. No great difference in the results of choosing the method of ACL graft fixation was revealed. The «all-inside» technology seems more promising. Correct positioning of the bone canals is very important. In the case of simultaneous meniscus injury it is necessary to perform a suture in order to preserve an important passive stabilizer of the knee joint.

Evaluation of Tibial Fixation Devices for Quadrupled Hamstring ACL Reconstruction.

Background:Shortcomings to tibial-side fixation have been reported as causes of failure after anterior cruciate ligament reconstruction. Adjustable-loop suspensory devices have become popular; however, no comparison with hybrid fixation (ie, interference screw and cortical button) exists to our knowledge.Purpose:The purpose of this study was to compare the biomechanical properties of adjustable loop devices (ALDs) in full-tunnel and closed-socket configurations in relation to hybrid fixation. We hypothesized that primary stability of fixation by a tibial ALD will not be inferior to hybrid fixation.Study Design:Controlled laboratory study.Methods:Tibial fixation of a quadrupled tendon graft was biomechanically investigated in a porcine tibia–bovine tendon model using 5 techniques (n = 6 specimens each). The tested constructs included hybrid fixation with a cortical fixation button and interference screw (group 1), single cortical fixation with the full-tunnel technique using an open-suture strand button (group 2) or an ALD (group 3), or closed-socket fixation using 2 different types of ALDs (groups 4 and 5). Each specimen was evaluated using a materials testing machine (1000 cycles from 50-250 N and pull to failure). Force at failure, cyclic displacement, stiffness, and ability to pretension the graft during insertion were compared among the groups.Results:No differences in ultimate load to failure were found between the ALD constructs (groups 3, 4, and 5) and hybrid fixation (group 1). Cyclic displacement was significantly higher in group 2 vs all other groups (P < .001); however, no difference was observed in groups 3, 4, and 5 as compared with group 1. The remaining tension on the construct after fixation was significantly higher in groups 3 and 4 vs groups 1, 2, and 5 (P < .02 for all comparisons), irrespective of whether a full-tunnel or closed-socket approach was used.Conclusion:Tibial anterior cruciate ligament graft fixation with knotless ALDs achieved comparable results with hybrid fixation in the full-tunnel and closed-socket techniques. The retention of graft tension appears to be biomechanically more relevant than tunnel type.Clinical Relevance:The study findings emphasize the importance of the tension at which fixation is performed.

Anterior Cruciate Ligament Patellar Tendon Autograft Fixation at 0° Versus 30° Results in Improved Activity Scores and a Greater Proportion of Patients Achieving the Minimal Clinical Important Difference For Knee Injury and Osteoarthritis Outcome Score Pain: A Randomized Controlled Trial

The aim of the current study was to determine the effect of the knee flexion angle (KFA) during tibial anterior cruciate ligament (ACL) graft fixation on patient-reported outcomes, graft stability, extension loss, and reoperation after anatomic single-bundle ACL reconstruction. All 169 included patients (mean age 28.5 years, 65% male) were treated with anatomic single-bundle ACL reconstruction using patellar tendon autograft and were randomized to tibial fixation of the ACL graft at either 0° (n= 85) or 30° (n= 84). The primary outcome was the Knee Injury and Osteoarthritis Outcome Score (KOOS) 2 years after surgery. Secondary outcomes were the Marx Activity Scale (MAS), the rate of reoperation, and physical examination findings at 1 year, including KT-1000 and side-to-side differences in knee extension. The follow-up rate was 82% (n= 139) for the primary outcome. Graft failure rate at 2 years was 1% (n= 2, 1 per group). ACL tibial graft fixation at 0° or 30° did not have a significant effect on KOOS scores at 2 years after ACLR. Patients whose graft was fixed at a knee flexion angle of 0° had greater scores on the MAS (mean 9.6 95% confidence interval [CI] 8.5 to 10.6, versus 8.0, 95% CI 6.9 to 9.1; P= .04), and a greater proportion achieved the minimal clinical important difference (MCID) for the KOOS pain subdomain (94% versus 81%; P= .04). There was no significant difference in knee extension loss, KT-1000 measurements, or reoperation between the 2 groups. In the setting of anatomic single-bundle ACLR using patellar tendon autograft and anteromedial portal femoral drilling, there was no difference in KOOS scores between patients fixed at 0° and 30°. Patient fixed in full extension did demonstrate higher activity scores at 2 years after surgery and a greater likelihood of achieving the MCID for KOOS pain. II, prospective randomized trial.

Anterolateral ligament reconstruction in addition to primary double-bundle anterior cruciate ligament reconstruction for grade 3 pivot shift improves residual knee instability during surgery

PurposeHigh-grade pivot shift in the anterior cruciate ligament (ACL) injured knee is a risk factor for postoperative residual pivot shift. Procedures in addition to ACL reconstruction such as anterolateral ligament (ALL) reconstruction have been performed for patients with a high-risk of residual pivot shift. The aim of this study was to investigate the effect of the addition of ALL reconstruction to primary double-bundle ACL reconstruction in patients with preoperative high-grade pivot shift to improve stability as evaluated by quantitative measurement.MethodsPatients with ACL injuries who showed preoperative grade 3 subjective pivot shift and who underwent primary double-bundle ACL reconstruction combined with ALL reconstructions were retrospectively enrolled. Anterior tibial translation (ATT) in the Lachman test, and acceleration and external rotational angular velocity (ERAV) in the pivot shift were measured as quantitative values. Quantitative values before surgical intervention for ACL-injured knees (ACLD) and uninjured contralateral knees (intact), after temporary fixation of the isolated ACL grafts (ACLR), and subsequently after temporary fixation of both ACL and ALL grafts (ACLR + ALLR) were measured with the patient under general anaesthesia.ResultsIn total, 18 patients were included. The ATT was lower in ACLR and ACLR + ALLR than in intact (P = .008 and .005), while there was no significant difference between ACLR and ACLR + ALLR (P > .05). The acceleration of ACLR + ALLR was lower than that for ACLR (P = .008), while there was no significant difference between intact and ACLR or ACLR + ALLR (P > .05). The ERAV of ACLR was higher than that of intact (P < .001), while that of ACLR + ALLR was lower than that of ACLR (P < 0.001), and there was no significant difference in ERAV between intact and ACLR + ALLR (P > 0.05).ConclusionAccording to quantitative assessment of the pivot shift, the addition of ALL reconstruction to primary double-bundle ACL reconstruction improved residual knee instability and restored knee stability during surgery. Combination of ALL reconstruction with primary double-bundle ACL reconstruction was effective for patients with ACL injuries exhibiting a preoperative grade 3 subjective pivot shift.Level of evidenceIV

Confirming Proper Button Deployment of Suspensory Fixation During ACL Reconstruction.

Background:Suspensory fixation of anterior cruciate ligament (ACL) reconstruction (ACLR) grafts has emerged as a popular device for femoral graft fixation. However, improper deployment of the suspensory fixation can compromise proper graft tensioning, leading to failure and revision. Also, soft tissue interposition between the button and bone has been associated with graft migration and pain, occasionally requiring revision surgery. Many surgeons rely on manual testing and application of distal tension to the graft to confirm proper button deployment on the lateral cortex of the femur for ACL graft fixation.Purpose:To determine the reliability of the manual resistance maneuver when applying distal tension to deploy the suspensory device along the lateral cortex of the femur.Study Design:Case series; Level of evidence, 4.Methods:All patients undergoing ACLR with a suture button suspensory device for femoral fixation were eligible for enrollment in the study. The surgeries were performed by 3 board-certified, sports medicine fellowship–trained orthopaedic surgeons at a single outpatient surgical center between May 2018 and June 2019. All grafts were passed in a retrograde manner into the femoral tunnel, and a vigorous manual tensioning maneuver in a distal direction was placed on the graft to deploy and secure along the lateral cortex of the femur. Intraoperative mini c-arm fluoroscopy was obtained to demonstrate proper suture button positioning. If interposing tissue or an improperly flipped button was identified, rectifying steps were undertaken and recorded.Results:A total of 51 patients with a mean age of 33.3 years were included in the study. Of these patients, 74.5% had normal suture button positioning identified via intraoperative fluoroscopic imaging, while 15.7% had interposed soft tissue and 9.8% had an improperly flipped button. In all cases, the surgeon was able to rectify the malpositioning intraoperatively.Conclusion:Despite the manual sensation of proper suspensory button positioning, intraoperative fluoroscopy identified suture button deployment errors in ACLR 25% of the time. Correcting the malpositioning is not technically demanding. These findings advocate for routine intraoperative surveillance to confirm appropriate suture button seating during ACLR.

Comparative Risk-Benefit Profiles of Individual Devices for Graft Fixation in Anterior Cruciate Ligament Reconstruction: A Systematic Review and Network Meta-analysis

To compare the efficacy and safety of individual devices for femoral and/or tibial graft fixation in anterior cruciate ligament (ACL) reconstruction. The PubMed, Embase, Cochrane Library, and Web of Science databases were searched from inception to December 12, 2018. Randomized controlled trials comparing individual devices for ACL graft fixation were included. Bayesian network meta-analysis was performed to assess the efficacy profile using the following outcomes: Lysholm score, International Knee Documentation Committee (IKDC) category, laxity, range of motion, and Tegner score. The incidence of infection, effusion, and graft rupture for each device was reported. We included 57 randomized controlled trials involving 4,304 patients aged 23.8 to 40.9 years. The female proportion ranged from 0% to 100%. The length of follow-up ranged from 6 to 144 months. Of the 13 studied femoral fixation devices, none was significantly different from the others regarding the Lysholm score, IKDC category, range of motion, and Tegner score. Bioabsorbable interference screws (standardized mean difference, 1.3; 95% credible interval, 0.0-2.5) showed higher laxity than the EndoPearl at a borderline level of statistical significance, but the difference varied substantially within multiple sensitivity analyses. Infection (2.0%) was most commonly seen with the EndoPearl, whereas the bone mulch screw had the highest incidence of effusion (5.5%) and graft rupture (5.5%). For the 9 studied tibial fixation devices, no significant difference was observed in the aforementioned efficacy measurements. Bioabsorbable interference screws with staples had the highest incidence of infection (11.1%) and effusion (15.6%), whereas graft rupture was most commonly seen with the bone plug (4.0%). Graft fixation devices in ACL reconstruction share a similar efficacy profile in terms of the Lysholm score, IKDC category, range of motion, and Tegner score but not laxity. On the other hand, safety profiles seem to vary among different devices. These findings can support surgeons, alongside their experience and preference, as well as the relative cost of each device, in delivering an individualized plan for an optimal operation. Level II, meta-analysis of Level I and II studies.

FUNCTIONAL OUTCOME OF ARTHROSCOPIC SINGLE BUNDLE ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION USING QUADRUPLE HAMSTRING GRAFT FIXED WITH ADJUSTABLE LOOP ENDO BUTTON AND BIO INTERFERENCE SCREW AT TERTIARY RURAL CENTRE

Objective: Anterior cruciate ligament (ACL) is the most common ligament to be replaced in the knee joint and ACL reconstruction (ACLR) is one of the most commonly performed surgery in orthopaedics nowadays. This study evaluated short term results of anterior cruciate ligament reconstruction with quadruple hamstring autograft using adjustable loop endobutton for femoral fixation and Bio absorbable interference screw for tibial fixation. Material and methods: 40 patients were operated for ACL reconstruction using quadruple autologous hamstring graft with adjustable loop endobutton and bio interference screw. Following the surgery the patients undergone standard rehabilitation protocol. The patients were followed up in OPD and their functional outcomes were measured by Lysholm scoring and IKDC scoring at 2 weeks, 8 weeks, 12 weeks, 24 weeks. Result: A total of 40 patients were evaluated in which there were 36 male patients and 4 female patients with a mean age of 26.75±5.95 and 25.25±7.27. The mean Lysholm score were 89.62±8.90 at 24 weeks of follow up compared to 79.38±11.32 at preoperative. The mean IKDC score were 85.06±9.35 at 24 weeks of follow up compared to 56.703±12.27 at preoperative. Conclusion: Arthroscopic ACL reconstruction and graft fixation using adjustable loop endobutton for the femoral end fixation and bioabsorbable interference screw fixation at the tibial end give an excellent result with minor complications. Keywords: ACL reconstruction, adjustable loop endobutton, hamstring graft.

Minimally Invasive Ultrasound-Guided Anterolateral Ligament Reconstruction With Autologous 2-Strand Gracilis Graft

We describe an ultrasound-guided anterolateral ligament (ALL) reconstruction technique that uses the gracilis tendon and can be added to any anterior cruciate ligament reconstruction technique. Preoperative ultrasound imaging is used to view the ruptured ALL and confirm the location of bony landmarks. Two minimally invasive incisions are made: one posterior to the lateral epicondyle and one posterior to the Gerdy tubercle. After anterior cruciate ligament graft fixation, the 2-strand gracilis tendon is introduced from the tibial incision, under the fascia lata, toward the femoral incision. The ALL graft is secured to the femur with a 5.5-mm anchor, positioned posteriorly and proximally to the lateral epicondyle. The distal end of the graft is tightened in full extension and fixed to the tibia with a ligament staple posterior to the Gerdy tubercle. This ALL technique requires no graft preparation.

Adjustable buttons for ACL graft cortical fixation partially fail with cyclic loading and unloading.

Despite good initial pullout strength, it is unclear whether adjustable button (AB) devices for anterior cruciate ligament (ACL) soft-tissue graft fixation, which are based on the Chinese finger trap technique, resist cyclic loading. Furthermore, they have never been tested in a cyclic protocol including complete unloading. It was hypothesized, that the displacement of AB devices with the Chinese finger trap technique would be greater than that of continuous suture loop devices and other available AB mechanisms in a cyclic loading with complete unloading protocol. ACL reconstruction was performed in a porcine knee model using three different types of cortical fixation devices: two different AB devices that use the Chinese finger trap design, one AB device that uses a locked suture loop mechanism and two different continuous loop devices as control groups (n = 40). Specimens were mounted in a material-testing machine (Instron Inc.) that permitted 2500 loading and complete unloading cycles to a maximum of 250N, as well as continuous elongation recording. A one-way ANOVA was performed for statistical analysis. The displacement of ABs with a Chinese finger trap loop (mean 8.1; SD 1.5mm and mean 6.1; SD 1.4mm) was significantly greater than that of AB with a locked suture loop (mean 4.7; SD 1.0mm; p < 0.05) and devices with a continuous loop (mean 4.1; SD 0.5mm and mean 4.4, SD 0.3mm; p < 0.01). No significant differences were detected between the ABs with a locked suture loop and the continuous loops. Cyclic loading and unloading of AB using the Chinese finger trap technique leads to significantly greater construct lengthening compared with other devices. Complete unloading of the ACL is very likely to occur during rehabilitation after ACL reconstruction. Lengthening of the AB device due to cyclic loading might be a potential mode of failure of the ACL graft fixation. Therefore, when using an AB femoral fixation technique, a locked suture loop design or a careful rehabilitation protocol should be considered.

Bicruciate lesion biomechanics, Part2-treatment using a simultaneous tensioning protocol: ACL fixation first is better than PCL fixation first to restore tibiofemoral orientation.

An uncommon technique for bicruciate ligament reconstruction involving simultaneous tensioning of the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) grafts with ACL graft fixation first has been pointed out as superior to the "gold-standard" PCL graft fixation first. The purpose of this study was to compare tibiofemoral biomechanics between ACL fixation first and PCL fixation first in a simultaneous tensioning protocol for bicruciate ligament reconstruction. 12 fresh-frozen cadaveric knees (six matched pairs) were tested using a custom testing system. Neutral tibial position representing tibiofemoral orientation, anterior-posterior (AP) tibial translation, varus-valgus laxity, and internal-external rotation were measured using a Microscribe 3DLX at 0°, 30°, 60°, and 90° of knee flexion. The following knee conditions were evaluated: intact, bicruciate deficient and following bicruciate reconstruction. A simultaneous tensioning protocol was used for bicruciate reconstruction and PCL fixation first was compared to ACL fixation first.PCL graft fixation was always performed at 90° of flexion and ACL graft fixation was always performed at full extension. ACL fixation first achieved a tibiofemoral orientation closer to the intact knee than PCL fixation first at 90° flexion (1.8 ± 1.6mm versus 6.1 ± 3.2mm, p = 0.016). PCL fixation first had a larger decrease in AP translation than ACL fixation first at 30° flexion (64.6 ± 3.5% vs. 58.3 ± 2.4%, p = 0.01). No significant differences were found for varus/valgus, external-internal rotation decrements after bicruciate reconstruction nor for AP translation, varus/valgus and internal/external rotation increase after bicruciate lesion comparing ACL fixation first to PCL fixation first. Bicruciate ligament reconstruction using a simultaneous tensioning protocol with ACL fixation first resulted in a closer to normal tibiofemoral orientation. This study will help guide surgeons in decision making for the graft tensioning protocol and fixation sequence in a bicruciate ligament reconstruction. V therapeutic study.

Screw oversizing for anterior cruciate ligament graft fixation in primary and enlarged tibial tunnels: A biomechanical study in a porcine model

BackgroundIdeal diameter for tibial interference screw fixation of the anterior cruciate ligament (ACL) graft remains controversial. Tibial graft fixation with screws matching the tunnel diameter vs. one-millimetre oversized screws were compared. MethodsIn 32 cadaveric porcine tibiae, bovine extensor tendons with a diameter of eight millimetres were fixed in (I) a primary ACL reconstruction scenario with eight-millimetre tibial tunnels (pACL), with eight-millimetre (pACL-8) vs. nine-millimetre (pACL-9) screws, and (II) a revision ACL reconstruction scenario with enlarged tunnels of 10 mm (rACL), with 10-mm (rACL-10) vs. 11-mm (rACL-11) screws. Specimens underwent cyclic loading with low and high load magnitudes followed by a load-to-failure test. Graft slippage and ultimate failure load were recorded. ResultsIn comparison with matched-sized screws (pACL-8), fixation with oversized screws (pACL-9) showed with significantly increased graft slippage during cyclic loading at higher load magnitudes (1.19 ± 0.23 vs. 1.98 ± 0.67 mm; P = 0.007). There were no significant differences between the two screw sizes in the revision scenario (rACL-10 vs. rACL-11; P = 0.38). Graft fixation in the revision scenario resulted in significantly increased graft slippage in comparison with fixation in primary tunnels at higher loads (pACL vs. rACL; P = 0.004). Pull-out strengths were comparable for both scenarios and all screw sizes (P > 0.316). ConclusionsMatched-sized interference screws provided better ACL graft fixation in comparison with an oversized screw diameter. In revision cases, the fixation strength of interference screws in enlarged tunnels was inferior to the fixation strength in primary tunnels.

The Influence of Graft Fixation Methods on Revision Rates After Primary Anterior Cruciate Ligament Reconstruction

Background: The method of graft fixation in primary anterior cruciate ligament (ACL) reconstruction is important for initial stability of the graft. Poor graft fixation can result in failure of the reconstruction. The effect of ACL graft fixation principles and fixation implant combinations on the risk of revision after ACL reconstruction is not well understood. Purpose: The study aimed to compare the risk of revision among 4 categories of femoral fixation divided by their principle of function using a hamstring tendon (HT) graft only. Furthermore, this study aimed to compare the risk of revision among the most frequently used combinations (tibia and femur) of graft fixation implants in a national patient cohort. Study Design: Cohort study; Level of evidence, 3. Methods: The authors divided the femoral fixation constructs into 4 categories by their principle of function: cortical suspensory fixation, adjustable cortical suspensory fixation, intratunnel transfixation, and interference screw (aperture) fixation. Data on revision rates and graft fixation methods were extracted from the Danish ACL Reconstruction Registry. The study included patients who underwent primary ACL reconstruction with either an HT or patellar tendon (PT) graft and were followed up at 2 to 10 years. Revision rates at 2-year and full follow-up were extracted for the category of graft fixation in the femur as well as for the most common implant combinations (those involving >175 patients). Patients with infrequently used fixation devices were excluded from this analysis. The HT group included 14 frequently used combinations (n > 175), and there were 2 such combinations in the PT group. A total of 13,200 ACL reconstructions were included in the study. For ACL reconstruction with an HT graft, there were 4680 with cortical suspensory fixation, 577 with adjustable cortical suspensory fixation, 5921 with intratunnel transfixation, and 617 with interference screw fixation. There were 1405 ACL reconstructions with a PT graft. Results: When only comparing primary ACL reconstructions using an HT graft, cortical suspensory fixation exhibited a significantly higher risk of revision at 2-year follow-up than the other categories of femoral fixation (hazard ratio [HR], 1.24 [95% CI, 1.07-1.44]; P < .05). Intratunnel transfixation exhibited a significantly lower risk of revision (HR, 0.83 [95% CI, 0.73-0.94]; P < .05). Comparing the most frequently used femoral/tibial fixation implant combinations with the mean risk of revision, Endobutton/Intrafix and Endobutton/Biosure PEEK for HT grafts exhibited an increased risk of revision, with an relative risk (RR) of 1.36 (95% CI, 1.03-1.81; P < .05) and 1.55 (95% CI, 1.15-2.09; P < .05), respectively. The Atlantech metal screw/metal screw and Softsilk/Softsilk combinations (both for PT grafts) exhibited a significantly decreased risk of revision, with an RR of 0.41 (95% CI, 0.18-0.91; P < .05) and 0.36 (95% CI, 0.15-0.87; P < .05), respectively. Conclusion: When comparing ACL graft fixation methods in the 4 categories using an HT graft, cortical suspensory fixation was found to have a significantly increased risk of revision, while intratunnel transfixation exhibited a lower risk of revision. Both Endobutton/Intrafix and Endobutton/Biosure PEEK implant combinations exhibited a significantly higher risk of revision. For PT grafts, Atlantech metal screw/metal screw and Softsilk/Softsilk exhibited a significantly lower risk of revision.