Function of posterior cruciate ligament bundles during in vivo knee flexion.

Background: The biomechanical functions of the anterolateral and posteromedial bundles of the posterior cruciate ligament over the range of flexion of the knee joint remain unclear.

Hypothesis: The posterior cruciate ligament bundles have minimal length at low flexion angles and maximal length at high flexion angles.

Study Design: Descriptive laboratory study.

The effect of anterior cruciate ligament deficiency on the in vivo elongation of the medial and lateral collateral ligaments.

Background: Although anterior cruciate ligament deficiency has been shown to lead to joint degeneration, few quantitative data have been reported on its effect on soft tissue structures surrounding the knee joint.

Hypothesis: Anterior cruciate ligament deficiency will alter the deformation of both collateral ligaments during in vivo weight-bearing knee function from 0 degrees to 90 degrees.

Study Design: Controlled laboratory study.

The biomechanical function of the patellar tendon during in-vivo weight-bearing flexion.

Few studies have investigated the function of the patellar tendon in-vivo. This study quantified the three-dimensional (3D) kinematics of the patellar tendon during weight-bearing flexion. Eleven subjects were imaged using magnetic resonance (MR).

In vivo kinematics of the knee after anterior cruciate ligament reconstruction: a clinical and functional evaluation.

Background: Recent follow-up studies have reported a high incidence of joint degeneration in patients with anterior cruciate ligament reconstruction. Abnormal kinematics after anterior cruciate ligament reconstruction have been thought to contribute to the degeneration.

Hypothesis: Anterior cruciate ligament reconstruction, which was designed to restore anterior knee laxity under anterior tibial loads, does not reproduce knee kinematics under in vivo physiological loading conditions.

Anterior cruciate ligament deficiency alters the in vivo motion of the tibiofemoral cartilage contact points in both the anteroposterior and mediolateral directions.

Background: Quantifying the effects of anterior cruciate ligament deficiency on joint biomechanics is critical in order to better understand the mechanisms of joint degeneration in anterior cruciate ligament-deficient knees and to improve the surgical treatment of anterior cruciate ligament injuries. We investigated the changes in position of the in vivo tibiofemoral articular cartilage contact points in anterior cruciate ligament-deficient and intact contralateral knees with use of a newly developed dual orthogonal fluoroscopic and magnetic resonance imaging technique.

Methods: Nine patients with an anterior cruciate ligament rupture in one knee and a normal contralateral knee were recruited.

The 6 degrees of freedom kinematics of the knee after anterior cruciate ligament deficiency: an in vivo imaging analysis.

Background: Previous studies of knee joint function after anterior cruciate ligament deficiency have focused on measuring anterior-posterior translation and internal-external rotation. Few studies have measured the effects of anterior cruciate ligament deficiency on 6 degrees of freedom knee kinematics in vivo.

Objective: To measure the 6 degrees of freedom knee kinematics of patients with anterior cruciate ligament deficiency.