Biomechanics Commons^™

Asymmetries In Dynamic Valgus Index After Anterior Cruciate Ligament Reconstruction: A Proof-Of-Concept Study, Kai Yu Ho, Andrew Murata

Physical Therapy Faculty Publications

Individuals with anterior cruciate ligament reconstruction (ACLR) are at a higher risk for subsequent anterior cruciate ligament (ACL) tears. Risk factors for ACL injuries likely involve a combination of anatomical, biomechanical, and neuromuscular factors. Dynamic knee valgus has been indicated as a possible biomechanical factor for future ACL injuries. Given that knee valgus is often accompanied by contralateral pelvic drop during single-leg activities, a dynamic valgus index (DVI) that quantifies combined kinematics of the knee and hip in the frontal plane has recently been developed. As the premise of asymmetrical DVI between limbs in the ACLR population has not been …

The Influence Of Sports-Related Concussion On Lower Extremity Injury Risk In Adolescent And Collegiate Athletes, Jason M. Avedesian

UNLV Theses, Dissertations, Professional Papers, and Capstones

Sports-related concussion (SRC) represents a major epidemiological concern in the adolescent and collegiate athlete populations, with conservative estimates of approximately four million SRCs occurring each year in the United States. While the majority of previous research has emphasized the management and recovery of the cognitive aspects of SRC, recent data indicates subtle motor behavior is altered following a concussive event. Injury surveillance literature indicates that adolescent and collegiate athletes are at an approximately 2–4 greater risk for lower extremity (LE) injury following an SRC when compared to matched controls and pre-SRC LE injury rates. Furthermore, athletes with a previous SRC …

Hamstring-Dominant Strategy Of The Bone–Patellar Tendon–Bone Graft Anterior Cruciate Ligament–Reconstructed Leg Versus Quadriceps-Dominant Strategy Of The Contralateral Intact Leg During High-Intensity Exercise In Male Athletes, Kostas Patras, Franceska Zampeli, Stavros Ristanis, Elias Tsepis, Giorgos Ziogas, Nikolaos Stergiou, Anastasios D. Georgoulis

Journal Articles

Purpose

The purpose of this study was to investigate the effect of anterior cruciate ligament (ACL) reconstruction on the quadriceps-dominant strategy as a parameter associated with the neuromuscular control of the knee joint.

Methods

In this study 14 competitive soccer players who had undergone ACL reconstruction with bone–patellar tendon–bone autograft and 14 healthy competitive soccer players performed two 10-minute treadmill runs, 1 at moderate intensity and 1 at high intensity. Electromyographic recordings were acquired by use of a telemetric system at the third, fifth, seventh, and tenth minute of the runs from the vastus lateralis and the biceps femoris bilaterally. …

Neuromechanical Analysis Of Anterior Cruciate Ligament Risk Factors In Female Collegiate Soccer Athletes, Nelson Cortes

Human Movement Sciences Theses & Dissertations

The anterior cruciate ligament (ACL) acts in an essential role to prevent anterior tibial displacement when experiencing jump-landing forces that are applied to the lower extremity; more than 100,000 injuries per year in the United States in sport activities that often require landing, deceleration-acceleration, cutting and pivoting actions have been reported. The aim of this study was to examine the nature of any lower limb coupling differences between a drop-jump and a side-step cutting actions, assess kinematic and kinetic differences between three tasks, and evaluate the effects of two landing techniques in biomechanical risk factors while performing two unanticipated tasks. …

Effect Of Femoral Tunnel Placement For Reconstruction Of The Anterior Cruciate Ligament On Tibial Rotation, Stavros Ristanis, Nikolaos Stergiou, Eleftheria Siarava, Aikaterini Ntoulia, Grigoris Mitsionis, Anastasios D. Georgoulis

Journal Articles

Background: Rotational knee movement after reconstruction of the anterior cruciate ligament has been difficult to quantify. The purpose of this study was to identify in vivo whether a more horizontal placement of the femoral tunnel (in the ten o'clock position rather than in the eleven o'clock position) can restore rotational kinematics, during highly demanding dynamic activities, in a knee in which a bone-patellar tendon-bone graft had been used to reconstruct the anterior cruciate ligament.

Methods: We evaluated ten patients in whom a bone-patellar tendon-bone graft had been used to reconstruct the anterior cruciate ligament with the femoral tunnel in the …

The Effects Of Gender On The Biomechanics Of The Hip During Athletic Maneuvers, Mikaela Boham

Boise State University Theses and Dissertations

Context: Females are two to eight times more likely to sustain an ACL injury than males participating in the same sport. The primary mechanism reported for noncontact ACL injury involves landing from a jump, unanticipated change of direction, and/or deceleration activities.

Objective: The purpose of this study was to determine if adolescent female athletes perform athletic activities with decreased hip and knee flexion angles, and decreased EMG activity of the gluteus medius relative to their male counterparts.

Design: Cohort study from local club basketball teams.

Setting: University Laboratory.

Participants: Ten healthy adolescent basketball athletes (5 females, 5 males).

Interventions: Each …

Anterior Cruciate Ligament Reconstruction With A Quadrupled Hamstrings Tendon Autograft Does Not Restore Tibial Rotation To Normative Levels During Landing From A Jump And Subsequent Pivoting, Vasilis Chouliaras, Stavros Ristanis, Constantina O. Moraiti, V. Tzimas, Nicholas Stergiou, Anastasios D. Georgoulis

Journal Articles

Aim. Recent research suggested that the anterior curciate ligament (ACL) reconstruction does not restore tibial rotation to normal levels when a bone patellar tendon bone (BPTB) graft is used during high demanding activities. Our goal was to determine if the usage of an alternative graft, as the quadrupled semitendinosus-gracilis (ST/G), restore tibial rotation to normal values in a population of athletically active individuals while performing a usual for their sport activity.

Methods. Eleven subjects, all reconstructed with an ST/G graft, were assessed in vivo, 9 months postoperatively, while they jumped off a 40 cm platform, landed on the ground and …

Tibial Rotation In Anterior Cruciate Ligament (Acl)-Deficient And Acl-Reconstructed Knees, Nikolaos Stergiou, Stavros Ristanis, Constantina O. Moraiti, Anastasios D. Georgoulis

Journal Articles

Excessive tibial rotation has been documented in ACL deficiency during walking. ACL reconstruction has been unable to correct this abnormality in activities that are more demanding than walking and involve both anterior and rotational loading of the knee. These findings persist regardless of graft selection for the ACL reconstruction [bone-patellar tendon-bone (BPTB) or semitendinosus-gracilis (ST/G)]. Based on this research work, we propose a theoretical perspective for the development of osteoarthritis in both the ACL deficient and the ACL reconstructed knee. We propose that excessive tibial rotation will lead to abnormal loading of the cartilage areas that are not commonly loaded …

Tibial Rotation Is Not Restored After Acl Reconstruction With A Hamstring Graft, Anastasios D. Georgoulis, Stavros Ristanis, Vasileios Chouliaras, Constantina O. Moraiti, Nikolaos Stergiou

Journal Articles

Recent research suggests ACL reconstruction does not re- store tibial rotation to normal levels during high demand activities when a bone-patellar tendon-bone graft is used. We asked if an alternative graft, the semitendinosus-gracilis (ST/G) tendon graft, could restore tibial rotation during a high demand activity. Owing to its anatomic similarity with the normal ACL we hypothesized the ST/G graft could re- store excessive tibial rotation to normal healthy levels along with a successful reinstatement of the clinical stability of the knee. We assessed tibial rotation in vivo, using gait analysis. We compared the knees of ACL reconstructed patients with an …

The Effect Of Anterior Cruciate Ligament Recontruction On Lower Extremity Relative Phase Dynamics During Walking And Running, Max J. Kurz, Nikolaos Stergiou, Ugo H. Buzzi, Anastasios D. Georgoulis

Journal Articles

The purpose of this investigation was to use relative phase dynamics to evaluate gait in individuals with a reconstructed anterior cruciate ligament (ACL) during walking and running. Relative phase dynamics can describe the coordination strategies between the interacting segments at the lower extremity. Ten subjects who had undergone ACL reconstruction using the central third of their patellar tendon and ten healthy controls walked and ran on a treadmill at a self-selected pace. Relative phase dynamics were calculated for the foot–shank and shank–thigh coordinative relation- ships. Statistical differences between the groups were noted for the foot– shank relationship (p<0.05) during both walking and running and for the shank–thigh relationship (p<0.05) during walking. Our results indicate that current ACL reconstructive techniques may result in altered relative phase dynamics. These changes in relative phase dynamics could be related to a loss of sensory information about joint position and velocity that is typically provided by the intact ACL. Additionally, relative phase adaptations could be a learned response from the early stages of postsurgical rehabilitation. Relative phase dynamics provide quantitative information about the dynamic status of the ACL-reconstructed knee that cannot be gained from the conventional time-series evaluation of gait analysis data. Relative phase dynamics measures should supplement the conventional gait analysis measures that are used today for the clinical evaluation of the functional dynamic stability of the reconstructed knee. The examination of relative phase dynamics could be clinically important for the quantification of new ACL surgical interventions and of patient performance at various stages of rehabilitation. Further research should incorporate relative phase dynamics to understand the influence of ACL reconstruction on coordination and functional patient outcomes.

Compensatory Mechanisms In Anterior Cruciate Ligament Deficiency, Anastasios Papadonikolakis, Lance Cooper, Nikolaos Stergiou, Anastasios D. Georgoulis, Panayotis N. Coucacos

Journal Articles

The literature cites numerous studies involving the analysis of movement patterns in anterior cruciate ligament deficient (ACLD) patients. Although several in vivo biomechanical studies have shown that ACLD patients develop protective mechanisms against degenerative diseases, it seems that these adaptations fail to protect the knee from future pathology. Some authors state that ACLD patients adapt to the injury by avoiding quadriceps contraction during gait when the knee is near full extension. However, others have found increased hamstrings and decreased gastrocnemius activity, which normally contribute to the stability of the knee. It seems that further in vivo biomechanical investigation is required …

Three-Dimensional Tibiofemoral Kinematics Of The Anterior Cruciate Ligament-Deficient And Reconstructed Knee During Walking, Anastasios D. Georgoulis, Anastasios Papadonikolakis, Christos D. Papageorgiou, Argyris Mitsou, Nikolaos Stergiou

Journal Articles

Background: It is possible that gait abnormalities may play a role in the pathogenesis of meniscal or chondral injury as well as osteoarthritis of the knee in patients with anterior cruciate ligament deficiency.

Hypothesis: The three-dimensional kinematics of anterior cruciate ligament-deficient knees are changed even during low-stress activities, such as walking, but can be restored by reconstruction.

Study Design: Case control study.

Methods: Using a three-dimensional optoelectronic gait analysis system, we examined 13 patients with anterior cruciate ligament-deficient knees, 21 patients with anterior cruciate ligament-reconstructed knees, and 10 control subjects with uninjured knees during walking.

Results: Normal patterns of knee …