Article

The effect of posterior cruciate ligament reconstruction on patellofemoral contact pressures in the knee joint under simulated muscle loads.

Orthopaedic Biomechanics Laboratory, Massachusetts General Hospital and Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02114, USA.
The American Journal of Sports Medicine (Impact Factor: 4.7). 01/2004; 32(1):109-15.
Source: PubMed

ABSTRACT The mechanism of cartilage degeneration in the patellofemoral joint (PFJ) and medial compartment of the knee following posterior cruciate ligament (PCL) injury remains unclear. PCL reconstruction has been recommended to restore kinematics and prevent long-term degeneration. The effect of current reconstruction techniques on PFJ contact pressures is unknown.
To measure PFJ contact pressures after PCL deficiency and reconstruction.
Eight cadaveric knees were tested with the PCL intact, deficient, and reconstructed. Contact pressures were measured at 30 degrees, 60 degrees, 90 degrees, and 120 degrees of flexion under simulated muscle loads. Knee kinematics were measured by a robotic testing system, and the PFJ contact pressures were measured using a thin film transducer. A single bundle achilles tendon allograft was used in the reconstruction.
PCL deficiency significantly increased the peak contact pressures measured in the PFJ relative to the intact knee under both an isolated quadriceps load of 400 N and a combined quadriceps/hamstrings load of 400 N/200 N. Reconstruction did not significantly reduce the increased contact pressures observed in the PCL-deficient knee.
The elevated contact pressures observed in the PCL-deficient knee and reconstructed knee might contribute to the long-term degeneration observed in both the non-operatively treated and PCL-reconstructed knees.

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    • "To evaluate the effectiveness of surgical treatment, few experimental studies have been conducted to measure the tibiofemoral and patellofemoral forces after PCL surgery (Kanamori et al., 2000; Skyhar et al., 1993). Gill et al. (2004) measured the contact pressures induced by ''native'', deficient and reconstructed PCL in the patellofemoral joint for different angles of knee flexion , by using a thin film transducer. They observed that contact pressures were higher for a PCL-deficient knee and for a reconstructed knee, which might contribute to the long-term degeneration observed in both nonoperatively treated and PCL-reconstructed knees. "
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