Evolving Techniques in ACL Graft Fixation

SummaryA test apparatus that allowed the stifle to move in five degrees of freedom was used to determine the effect of graft location, graft preload, and flexion angle at the time of graft fixation on the tensile graft forces experienced by a replacement graft material used to simulate reconstruction of the cranial cruciate ligament deficient stifle. Two graft locations (tibial insertion site of the patellar ligament and tibial insertion site of the cranial cruciate ligament), two graft preloads (5 N and 20 N), and three flexion angles at the time of graft fixation (15°, 30° and 90°) were examined. The tibial insertion site and preload did not have as great an effect on graft force as did the flexion angle of the limb at time of graft fixation. Graft forces were highest when reconstructions were performed with the limb in 90° of flexion (ρ <0.0001). This study supports the notion that intracapsular grafts should be fixed with the limb in a normal standing angle.A five degree of freedom test apparatus was used to evaluate the effect of graft location, graft preload, and limb flexion angle at time of graft fixation on reconstructions of the cranial cruciate ligament deficient stifle. Our results suggest that intracapsular grafts should not be fixed with the limb in 90° of flexion, but in a normal standing angle.

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The Effect of Knee Flexion Angle for Graft Fixation During Single-Bundle Anterior Cruciate Ligament Reconstruction

Case Medical Research ◽

10.31525/ct1-nct03875807 ◽

2019 ◽

Author(s):

Keyword(s):

Anterior Cruciate Ligament ◽

Anterior Cruciate Ligament Reconstruction ◽

Knee Flexion ◽

Ligament Reconstruction ◽

Cruciate Ligament ◽

Graft Fixation ◽

Single Bundle ◽

Knee Flexion Angle ◽

Cruciate Ligament Reconstruction ◽

Anterior Cruciate

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Posterior Medial Meniscus Root Tears Potentiate the Effect of Increased Tibial Slope on ACL Graft Forces: Response

The American Journal of Sports Medicine ◽

10.1177/03635465211021416 ◽

2021 ◽

Vol 49 (9) ◽

pp. NP39-NP40

Author(s):

Robert F. LaPrade ◽

Brian T. Samuelson ◽

Grant J. Dornan

Keyword(s):

Medial Meniscus ◽

Tibial Slope ◽

Acl Graft ◽

Meniscus Root

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Interference Screw Versus Suture Anchors for Femoral Fixation in Medial Patellofemoral Ligament Reconstruction: A Biomechanical Study

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967121989282 ◽

2021 ◽

Vol 9 (3) ◽

pp. 232596712198928

Author(s):

Heath P. Gould ◽

Nicholas R. Delaney ◽

Brent G. Parks ◽

Roshan T. Melvani ◽

Richard Y. Hinton

Keyword(s):

Medial Patellofemoral Ligament ◽

Interference Screw ◽

Biomechanical Study ◽

Graft Fixation ◽

Mpfl Reconstruction ◽

Suture Anchors ◽

Femoral Fixation ◽

Significant Difference ◽

Load To Failure ◽

The Mean

Background: Femoral-sided graft fixation in medial patellofemoral ligament (MPFL) reconstruction is commonly performed using an interference screw (IS). However, the IS method is associated with several clinical disadvantages that may be ameliorated by the use of suture anchors (SAs) for femoral fixation. Purpose: To compare the load to failure and stiffness of SAs versus an IS for the femoral fixation of a semitendinosus autograft in MPFL reconstruction. Study Design: Controlled laboratory study. Methods: Based on a priori power analysis, a total of 6 matched pairs of cadaveric knees were included. Specimens in each pair were randomly assigned to receive either SA or IS fixation. After an appropriate reconstruction procedure, the looped end of the MPFL graft was pulled laterally at a rate of 6 mm/s until construct failure. The best-fit slope of the load-displacement curve was then used to calculate the stiffness (N/mm) in a post hoc fashion. A paired t test was used to compare the mean load to failure and the mean stiffness between groups. Results: No significant difference in load to failure was observed between the IS and the SA fixation groups (294.0 ± 61.1 vs 250.0 ± 55.9; P = .352), although the mean stiffness was significantly higher in IS specimens (34.5 ± 9.6 vs 14.7 ± 1.2; P = .004). All IS reconstructions failed by graft pullout from the femoral tunnel, whereas 5 of the 6 SA reconstructions failed by anchor pullout. Conclusion: In this biomechanical study using a cadaveric model of MPFL reconstruction, SA femoral fixation was not significantly different from IS fixation in terms of load to failure. The mean load-to-failure values for both reconstruction techniques were greater than the literature-reported values for the native MPFL. Clinical Relevance: These results suggest that SAs are a biomechanically viable alternative for femoral-sided graft fixation in MPFL reconstruction.

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Confirming Proper Button Deployment of Suspensory Fixation During ACL Reconstruction

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967120974349 ◽

2021 ◽

Vol 9 (1) ◽

pp. 232596712097434

Author(s):

Daniel F. O’Brien ◽

Lilah Fones ◽

Victoria Stoj ◽

Cory Edgar ◽

Katherine Coyner ◽

...

Keyword(s):

Soft Tissue ◽

Acl Reconstruction ◽

Sports Medicine ◽

Cruciate Ligament ◽

Case Series ◽

Graft Fixation ◽

Level Of Evidence ◽

Lateral Cortex ◽

Suture Button ◽

Suspensory Fixation

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.

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