• BACKGROUND
    • The lowest contact pressure point is presumed to be the best site to harvest an osteochondral plug and minimize morbidity.
  • HYPOTHESIS
    • Patellofemoral contact pressures are not uniform and are lowest along the medial patellofemoral articulation.
  • STUDY DESIGN
    • Controlled laboratory study.
  • METHODS
    • Seven cadaveric knees were tested with an electroresistive, dynamic pressure sensor placed onto the femoral side of the patellofemoral joint. The extensor mechanism was loaded with 89.1 N and 178.2 N, and the knee was manually cycled 3 times (0 degrees -105 degrees ) per load. Mean trochlear pressures were calculated.
  • RESULTS
    • Mean contact pressures were greatest in the central trochlea (5.80 kgf/cm(2)), followed by the lateral (2.56 kgf/cm(2)) and medial trochlea (1.60 kgf/cm(2)) at 89.1 N (P <.05). At 178.2 N, pressures increased to 9.47, 5.81, and 2.75 kgf/cm(2), respectively (P <.05). Lateral trochlear pressures decreased moving distally from 1.25 to 0.50 kgf/cm(2) at 89.1 N and 4.57 to 1.29 kgf/cm(2) at 178.2 N.
  • CONCLUSIONS
    • Contact pressures are lowest along the medial trochlea and decrease distally along the lateral trochlea.
  • CLINICAL RELEVANCE
    • Osteochondral plugs from the medial femoral trochlea may be desirable if trochlear size permits. If harvesting from the lateral femoral trochlea, consider harvesting distally near the sulcus terminalis.