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Thomas J Gill - One of the best experts on this subject based on the ideXlab platform.
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analysis of tibiofemoral cartilage deformation in the Posterior Cruciate Ligament deficient knee
Journal of Bone and Joint Surgery American Volume, 2009Co-Authors: Samuel K Van De Velde, Jeffrey T Bingham, Thomas J GillAbstract:Background: Degeneration of the tibiofemoral articular cartilage often develops in patients with Posterior Cruciate Ligament deficiency, yet little research has focused on the etiology of this specific type of cartilage degeneration. In this study, we hypothesized that Posterior Cruciate Ligament deficiency changes the location and magnitude of cartilage deformation in the tibiofemoral joint. Methods: Fourteen patients with a Posterior Cruciate Ligament injury in one knee and the contralateral side intact participated in the study. First, both knees were imaged with use of a specific magnetic resonance imaging sequence to create three-dimensional knee models of the surfaces of the bone and cartilage. Next, each patient performed a single leg lunge as images were recorded with a dual fluoroscopic system at 0°, 30°, 60°, 75°, 90°, 105°, and 120° of knee flexion. Finally, the three-dimensional knee models and fluoroscopic images were used to reproduce the in vivo knee position at each flexion angle with use of a previously described image-matching method. With use of these series of knee models, the location and magnitude of peak tibiofemoral cartilage deformation at each flexion angle were compared between the intact contralateral and Posterior Cruciate Ligament-deficient knees. Results: In the medial compartment of the Posterior Cruciate Ligament-deficient knees, the location and magnitude of peak cartilage deformation were significantly changed, compared with those in the intact contralateral knees, between 75° and 120° of flexion, with a more anterior and medial location of peak cartilage deformation on the tibial plateau as well as increased deformation of the cartilage. In the lateral compartment, no significant differences in the location or magnitude of peak cartilage deformation were found between the intact and Posterior Cruciate Ligament-deficient knees. Conclusions: The altered kinematics associated with Posterior Cruciate Ligament deficiency resulted in a shift of the tibiofemoral contact location and an increase in cartilage deformation in the medial compartment beyond 75° of knee flexion. The magnitude of the medial contact shift in the Posterior Cruciate Ligament-deficient knee was on the same order as that of the anterior contact shift. Clinical Relevance: The observed changes in the location and magnitude of cartilage deformation in the tibiofemoral joint provide insight about the development of degeneration of the tibiofemoral joint cartilage in patients with Posterior Cruciate Ligament deficiency. Our data also suggest that recreating mediolateral stability of Posterior Cruciate Ligament-deficient knees might be of importance in addition to surgically improving anteroPosterior translation.
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function of Posterior Cruciate Ligament bundles during in vivo knee flexion
American Journal of Sports Medicine, 2007Co-Authors: Ramprasad Papannagari, Louis E Defrate, Kyung Wook Nha, Jeremy M Moses, Mohamed Moussa, Thomas J GillAbstract:BackgroundThe biomechanical functions of the anterolateral and posteromedial bundles of the Posterior Cruciate Ligament over the range of flexion of the knee joint remain unclear.HypothesisThe Posterior Cruciate Ligament bundles have minimal length at low flexion angles and maximal length at high flexion angles.Study DesignDescriptive laboratory study.MethodsSeven knees from normal, healthy subjects were scanned with magnetic resonance, and 3-dimensional models of the femur, tibia, and Posterior Cruciate Ligament attachment sites were created. The lines connecting the centroids of the corresponding bundle attachment sites on the femur and tibia represented the anterolateral and posteromedial bundles of the Posterior Cruciate Ligament. Each knee was imaged during weightbearing flexion (from 0° to maximal flexion) using a dual-orthogonal fluoroscopic system. The length, elevation, deviation, and twist of the Posterior Cruciate Ligament bundles were measured as a function of flexion.ResultsThe lengths of the...
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in vivo function of the Posterior Cruciate Ligament during weightbearing knee flexion
American Journal of Sports Medicine, 2004Co-Authors: Louis E Defrate, Thomas J GillAbstract:BackgroundCurrent knowledge of Posterior Cruciate Ligament function is mainly based on in vitro cadaveric studies. There are few studies on the in vivo function of the Posterior Cruciate Ligament. The objective of the study was to quantify the multidimensional deformation of the Posterior Cruciate Ligament.HypothesisDuring in vivo weightbearing flexion, the Posterior Cruciate Ligament undergoes complex 3-dimensional deformations, including elongation, twist, and changes in orientation.Study DesignIn vivo biomechanical study.MethodsMagnetic resonance images of 5 human knees were used to create 3-dimensional computer models of each subject's knee, including the insertion areas of the Posterior Cruciate Ligament. Orthogonal fluoroscopic images of each subject's knee were acquired as a quasi-static lunge was performed. The images and computer models were used to reproduce the in vivo motion of the knee. The relative motion of the femoral and tibial insertions was described in terms of elongation, twist, eleva...
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the effect of Posterior knee capsulotomy on Posterior tibial translation during Posterior Cruciate Ligament tibial inlay reconstruction
American Journal of Sports Medicine, 2004Co-Authors: Sang Eun Park, Louis E Defrate, Bruce D Stamos, Thomas J GillAbstract:Purpose: To measure the biomechanical effect of the surgical capsulotomy made during a Posterior Cruciate Ligament reconstruction using the tibial inlay technique.Hypothesis: The Posterior capsule contributes to Posterior tibial stability.Study Design: Controlled laboratory experiment.Methods: Six knee specimens were tested on a robotic testing system from 0° to 120° of flexion with the Posterior Cruciate Ligament intact and resected and with a Posterior capsulotomy identical to that performed during tibial inlay reconstruction (sham surgery). A longitudinal incision with medial and lateral soft tissue stripping sufficient to mount an inlay bone block and pass an Achilles tendon graft into the knee was made in the oblique popliteal Ligament, muscle belly of the popliteus, and Posterior capsule. The Posterior tibial translation was measured under a Posterior tibial load of 130 N at multiple flexion angles.Results: Capsulotomy increased the Posterior laxity compared with the Posterior Cruciate Ligament–rese...
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In Vivo Elongation of the Anterior Cruciate Ligament and Posterior Cruciate Ligament During Knee Flexion
The American journal of sports medicine, 2004Co-Authors: Louis E Defrate, Hao Sun, Thomas J GillAbstract:BackgroundMost knowledge regarding Cruciate Ligament function is based on in vitro experiments.PurposeTo investigate the in vivo elongation of the functional bundles of the anterior Cruciate Ligament and Posterior Cruciate Ligament during weightbearing flexion.HypothesisThe biomechanical role of functional bundles of the anterior Cruciate Ligament and Posterior Cruciate Ligament under in vivo loading is different from that measured in cadavers.Study DesignIn vivo biomechanical study.MethodsElongation of the anterior Cruciate Ligament and Posterior Cruciate Ligament was measured during a quasi-static lunge using imaging and 3-dimensional computer-modeling techniques.ResultsThe anterior-medial bundle of the anterior Cruciate Ligament had a relatively constant length from full extension to 90° of flexion. The Posterior-lateral bundle of the anterior Cruciate Ligament decreased in length with flexion. Both bundles of the Posterior Cruciate Ligament had increased lengths with flexion.ConclusionThe data did not...
Robert F Laprade - One of the best experts on this subject based on the ideXlab platform.
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tibial slope and its effect on graft force in Posterior Cruciate Ligament reconstructions
American Journal of Sports Medicine, 2019Co-Authors: Andrew S Bernhardson, Zachary S Aman, Nicholas N Dephillipo, Grant J Dornan, Hunter W Storaci, Alex W Brady, Gilberto Yoshinobu Nakama, Robert F LapradeAbstract:Background:A flattened Posterior tibial slope may cause excessive unwanted stress on the Posterior Cruciate Ligament (PCL) reconstruction graft and place patients at risk for PCL reconstruction gra...
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Posterior Cruciate Ligament current concepts review
The archives of bone and joint surgery, 2018Co-Authors: Santiago Pache, Zachary S Aman, Gilberto Yoshinobu Nakama, Mitchell I Kennedy, Gilbert Moatshe, Connor G Ziegler, Robert F LapradeAbstract:The Posterior Cruciate Ligament (PCL) is the largest and strongest Ligament in the human knee, and the primary Posterior stabilizer. Recent anatomy and biomechanical studies have provided an improved understanding of PCL function. PCL injuries are typically combined with other Ligamentous, meniscal and chondral injuries. Stress radiography has become an important and validated objective measure in surgical decision making and post-operative assessment. Isolated grade I or II PCL injuries can usually be treated non-operatively. However, when acute grade III PCL ruptures occur together with other Ligamentous injury and/or repairable meniscal body/root tears, surgery is indicated. Anatomic single-bundle PCL reconstruction (SB-PCLR) typically restores the larger anterolateral bundle (ALB) and represents the most commonly performed procedure. Unfortunately, residual Posterior and rotational tibial instability after SB-PCLR has led to the development of an anatomic double-bundle (DB) PCLR to restore the native PCL footprint and co-dominant behavior of the anterolateral and posteromedial bundles and re-establish normal knee kinematics. The purpose of this article is to review the pertinent details regarding PCL anatomy, biomechanics, injury diagnosis and treatment options, with a focus on arthroscopically assisted DB-PCLR. Level of evidence: IV.
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anatomic double bundle Posterior Cruciate Ligament reconstruction
Arthroscopy techniques, 2016Co-Authors: Jorge Chahla, Marco Nitri, David M Civitarese, Chase S Dean, Samuel G Moulton, Robert F LapradeAbstract:The Posterior Cruciate Ligament (PCL) is known to be the main Posterior stabilizer of the knee. Anatomic single-bundle PCL reconstruction, focusing on reconstruction of the larger anterolateral bundle, is the most commonly performed procedure. Because of the residual Posterior and rotational tibial instability after the single-bundle procedure and the inability to restore the normal knee kinematics, an anatomic double-bundle PCL reconstruction has been proposed in an effort to re-create the native PCL footprint more closely and to restore normal knee kinematics. We detail our technique for an anatomic double-bundle PCL reconstruction using Achilles and anterior tibialis tendon allografts.
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quantification of functional brace forces for Posterior Cruciate Ligament injuries on the knee joint an in vivo investigation
Knee Surgery Sports Traumatology Arthroscopy, 2015Co-Authors: Robert F Laprade, Sean D Smith, Katharine J Wilson, Coen A WijdicksAbstract:Purpose Counteracting Posterior translation of the tibia with an anterior force on the Posterior proximal tibia has been demonstrated clinically to improve Posterior knee laxity following Posterior Cruciate Ligament (PCL) injury. This study quantified forces applied to the Posterior proximal tibia by two knee braces designed for treatment of PCL injuries.
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Posterior Cruciate Ligament graft fixation angles part 1 biomechanical evaluation for anatomic single bundle reconstruction
American Journal of Sports Medicine, 2014Co-Authors: Nicholas I Kennedy, Robert F Laprade, Mary T Goldsmith, Scott C Faucett, Matthew T Rasmussen, Garrett A Coatney, Lars Engebretsen, Coen A WijdicksAbstract:Background:Currently, no consensus exists for the optimal graft fixation angle for anatomic single-bundle (SB) Posterior Cruciate Ligament reconstructions (PCLRs). Additionally, direct graft forces have not been measured. Alternative graft fixation angles and the resultant graft forces should be investigated to optimize the stability of SB PCLRs without overconstraining the knee.Hypothesis:Graft fixation angles of 75°, 90°, and 105° for SB PCLR were hypothesized to improve knee stability compared with the sectioned Posterior Cruciate Ligament state with no evidence of knee overconstraint.Study Design:Controlled laboratory study.Methods:Nine fresh-frozen human cadaveric knees were biomechanically evaluated for the intact, sectioned, and SB PCLR states with the anterolateral bundle graft fixed at 75°, 90°, and 105°. A 6 degrees of freedom robotic system assessed knee laxity with a 134-N Posterior load applied at 0° to 120° and 5-N·m external, 5-N·m internal, and 10-N·m valgus rotation torques applied at 60°...
Louis E Defrate - One of the best experts on this subject based on the ideXlab platform.
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function of Posterior Cruciate Ligament bundles during in vivo knee flexion
American Journal of Sports Medicine, 2007Co-Authors: Ramprasad Papannagari, Louis E Defrate, Kyung Wook Nha, Jeremy M Moses, Mohamed Moussa, Thomas J GillAbstract:BackgroundThe biomechanical functions of the anterolateral and posteromedial bundles of the Posterior Cruciate Ligament over the range of flexion of the knee joint remain unclear.HypothesisThe Posterior Cruciate Ligament bundles have minimal length at low flexion angles and maximal length at high flexion angles.Study DesignDescriptive laboratory study.MethodsSeven knees from normal, healthy subjects were scanned with magnetic resonance, and 3-dimensional models of the femur, tibia, and Posterior Cruciate Ligament attachment sites were created. The lines connecting the centroids of the corresponding bundle attachment sites on the femur and tibia represented the anterolateral and posteromedial bundles of the Posterior Cruciate Ligament. Each knee was imaged during weightbearing flexion (from 0° to maximal flexion) using a dual-orthogonal fluoroscopic system. The length, elevation, deviation, and twist of the Posterior Cruciate Ligament bundles were measured as a function of flexion.ResultsThe lengths of the...
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in vivo function of the Posterior Cruciate Ligament during weightbearing knee flexion
American Journal of Sports Medicine, 2004Co-Authors: Louis E Defrate, Thomas J GillAbstract:BackgroundCurrent knowledge of Posterior Cruciate Ligament function is mainly based on in vitro cadaveric studies. There are few studies on the in vivo function of the Posterior Cruciate Ligament. The objective of the study was to quantify the multidimensional deformation of the Posterior Cruciate Ligament.HypothesisDuring in vivo weightbearing flexion, the Posterior Cruciate Ligament undergoes complex 3-dimensional deformations, including elongation, twist, and changes in orientation.Study DesignIn vivo biomechanical study.MethodsMagnetic resonance images of 5 human knees were used to create 3-dimensional computer models of each subject's knee, including the insertion areas of the Posterior Cruciate Ligament. Orthogonal fluoroscopic images of each subject's knee were acquired as a quasi-static lunge was performed. The images and computer models were used to reproduce the in vivo motion of the knee. The relative motion of the femoral and tibial insertions was described in terms of elongation, twist, eleva...
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the effect of Posterior knee capsulotomy on Posterior tibial translation during Posterior Cruciate Ligament tibial inlay reconstruction
American Journal of Sports Medicine, 2004Co-Authors: Sang Eun Park, Louis E Defrate, Bruce D Stamos, Thomas J GillAbstract:Purpose: To measure the biomechanical effect of the surgical capsulotomy made during a Posterior Cruciate Ligament reconstruction using the tibial inlay technique.Hypothesis: The Posterior capsule contributes to Posterior tibial stability.Study Design: Controlled laboratory experiment.Methods: Six knee specimens were tested on a robotic testing system from 0° to 120° of flexion with the Posterior Cruciate Ligament intact and resected and with a Posterior capsulotomy identical to that performed during tibial inlay reconstruction (sham surgery). A longitudinal incision with medial and lateral soft tissue stripping sufficient to mount an inlay bone block and pass an Achilles tendon graft into the knee was made in the oblique popliteal Ligament, muscle belly of the popliteus, and Posterior capsule. The Posterior tibial translation was measured under a Posterior tibial load of 130 N at multiple flexion angles.Results: Capsulotomy increased the Posterior laxity compared with the Posterior Cruciate Ligament–rese...
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In Vivo Elongation of the Anterior Cruciate Ligament and Posterior Cruciate Ligament During Knee Flexion
The American journal of sports medicine, 2004Co-Authors: Louis E Defrate, Hao Sun, Thomas J GillAbstract:BackgroundMost knowledge regarding Cruciate Ligament function is based on in vitro experiments.PurposeTo investigate the in vivo elongation of the functional bundles of the anterior Cruciate Ligament and Posterior Cruciate Ligament during weightbearing flexion.HypothesisThe biomechanical role of functional bundles of the anterior Cruciate Ligament and Posterior Cruciate Ligament under in vivo loading is different from that measured in cadavers.Study DesignIn vivo biomechanical study.MethodsElongation of the anterior Cruciate Ligament and Posterior Cruciate Ligament was measured during a quasi-static lunge using imaging and 3-dimensional computer-modeling techniques.ResultsThe anterior-medial bundle of the anterior Cruciate Ligament had a relatively constant length from full extension to 90° of flexion. The Posterior-lateral bundle of the anterior Cruciate Ligament decreased in length with flexion. Both bundles of the Posterior Cruciate Ligament had increased lengths with flexion.ConclusionThe data did not...
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the effect of length on the structural properties of an achilles tendon graft as used in Posterior Cruciate Ligament reconstruction
American Journal of Sports Medicine, 2004Co-Authors: Louis E Defrate, Alexander Van Der Ven, Thomas J GillAbstract:BackgroundThe clinical outcomes of Posterior Cruciate Ligament reconstruction are varied. No previous studies have investigated the effect of graft length on the structural properties of the graft.HypothesisGraft length significantly affects the structural properties of Posterior Cruciate Ligament grafts.Study DesignControlled laboratory study.MethodsEight Achilles tendon grafts were tested under tensile loads up to 400 N at 3 different lengths: long (75 mm), medium (48 mm), and short (34 mm). These 3 lengths represent midtunnel fixation, inlay fixation, and fixation near the Ligament insertions.ResultsShortening the graft from both long to medium and from medium to short increased the stiffness by approximately 25%. Long and medium grafts displaced significantly more than medium and short grafts, respectively.ConclusionThe effective length of a graft, which is determined by where it is fixed, should be considered an important variable in Posterior Cruciate Ligament reconstruction.
L D Morrison - One of the best experts on this subject based on the ideXlab platform.
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the Posterior Cruciate Ligament in total knee surgery save sacrifice or substitute
Clinical Orthopaedics and Related Research, 1994Co-Authors: H S Hirsch, P A Lotke, L D MorrisonAbstract:To determine the role of the Posterior Cruciate Ligament in total knee arthroplasty, 242 consecutive primary total knee arthroplasties were included in 1 of 3 sequential groups. Group I included 77 Press Fit Condylar total knee replacements in which the Posterior Cruciate Ligament was completely released from its tibial attachment. In Group II, there were 80 Press Fit Condylar total knee replacements in which the Posterior Cruciate Ligament was retained. Group III consisted of 85 total knee replacements with a Posterior Cruciate-substituting device (Insall-Burstein II). All patients were observed at least 2 years and evaluated by the Knee Society's Clinical and Functional Scoring System, including a radiographic evaluation
Richard S Laskin - One of the best experts on this subject based on the ideXlab platform.
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total knee replacement with Posterior Cruciate Ligament retention in rheumatoid arthritis problems and complications
Clinical Orthopaedics and Related Research, 1997Co-Authors: Richard S Laskin, Hugh OflynnAbstract:A series of patients with rheumatoid arthritis underwent total knee replacement with Posterior Cruciate Ligament retention and was observed a minimum of 6 years and a mean of 8.2 years. A group of patients with osteoarthritis with an identical prosthesis and a group of patients with rheumatoid arthritis with a Posterior stabilized implant served as controls. In the rheumatoid arthritis group with Posterior Cruciate Ligament retention, there was an increased incidence in Posterior instability and recurvatum deformity, resulting in an increased revision rate. Those patients undergoing revision for instability had a higher incidence of recurrent synovitis, and at revision the Posterior Cruciate Ligament was grossly absent with a Grade I synovial reaction. In patients with rheumatoid arthritis undergoing total knee replacement, a Posterior stabilized prosthesis rather than a Posterior Cruciate Ligament sparing prosthesis should be used.
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total knee replacement with Posterior Cruciate Ligament retention in patients with a fixed varus deformity
Clinical Orthopaedics and Related Research, 1996Co-Authors: Richard S LaskinAbstract:A group of patients with a preoperative varus contracture of at least 15 degrees underwent total knee replacement with retention of the Posterior Cruciate Ligament. Their outcomes at 10 years were compared with a group of patients with similar contractures in whom a Posterior stabilized implant was used, and to a group of patients in whom there was no contracture. In the contracture group where the Posterior Cruciate Ligament was retained, there was an increased incidence of pain, an increased incidence of bone cement radiolucencies, and a decrease in the eventual flexion arc. There was likewise an increased revision rate and a decreased survivorship. In patients with such contractures, the Posterior Cruciate Ligament is a part of the deformity; the deformity cannot be corrected by medial release procedures alone. All these results suggest that for the patient with a fixed varus contracture a Posterior Cruciate release should be performed and a Posterior stabilized type of implant used.
