About This File
This model is the right knee bone rendering of a 65-year-old male with left thigh myxoid fibrosarcoma. At the time of diagnosis, the patient had metastases to his lungs. The patient therefore underwent neoadjuvant radiotherapy, surgery, and adjuvant chemotherapy and was found to have an intermediate grade lesion at the time of diagnosis. The patient is still living with the metastatic disease at 2.5 years since diagnosis. This is an STL file created from DICOM images of his CT scan which may be used for 3D printing.
The knee is composed of 3 separate joints: two hinge joints (medial and lateral femorotibial joints), and one sellar, or gliding, joint (the patellofemoral joint). These also compose the three compartments of the knee: medial, lateral, and patellofemoral. Although the knee is thought of as a hinge joint, it has 6 degrees of motion: extension/flexion, internal/external rotation, varus/valgus, anterior/posterior translation, medial/lateral translation, and compression/distraction. To provide stability to the joint, static and dynamic stabilizers surround the knee, including muscles and ligaments.
The major ligaments that provide stability to the knee include the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), lateral (or fibular) collateral ligament (LCL), and medial collateral ligament (MCL). The ACL prevents anterior translation of the knee and the PCL prevents posterior translation of the knee. The LCL prevents varus stresses and the MCL prevents valgus stresses on the knee. Furthermore, the medial meniscus is a secondary stabilizer to anterior translation and is therefore commonly injured during an ACL tear or after an untreated ACL tear.
This model was created from the file STS_022.