Biomedical subjects
S Plaweski
Publications and source records attributed to S Plaweski.
Bone morphing: 3D morphological data for total knee arthroplasty.
OBJECTIVE: The clinical outcome of a total knee arthroplasty (TKA) is mainly determined by the accuracy of the surgical procedure itself. To improve the final result, one must take into account (a) the alignment of the prosthesis with respect to the mechanical axis, and (b) the balance of the soft tissues. Therefore, morphologic data (such as the shape of the epiphysis) and geometric data are essential. We present a new method for performing TKA based on morphologic and geometric data without preoperative images. MATERIALS AND METHODS: The global method is based on the digitization of points with an optical 3D localizer. For the morphologic acquisitions, we use a method based on the registration of sparse point data with a 3D statistical deformable model. To build the mechanical axis, we use a kinematics method for the hip center and digitization of anatomical landmarks for the ankle centers. The knee center is not determined by digitization or kinematics of the knee, as this would not be accurate. The surgical planning relies totally on the soft-tissue balance, which is the key issue for a good kinematics result. RESULTS: We have used this system for 6 months in a randomized clinical trial involving 35 patients to date. For the first 11 patients that could be measured in the navigation group, the postoperative frontal alignment was within the range of 180 +/- 3 degrees. Fluoroscopic assessment of the soft-tissue balancing will be performed at the conclusion of an extended 2-year study to evaluate the results from a functional point of view. CONCLUSION: Bone Morphing is an accurate, fast, and user-friendly method that can provide morphologic as well as geometric data. We have introduced the important notion of soft-tissue balancing into the intraoperative planning step to optimize the kinematics as well as the anatomy. Therefore, this method should be considered as an alternative to the CT-based method.
[Primary bone leiomyosarcoma. Anatomo-clinical case with immunohistochemistry study and review of the literature].
We describe a primary leiomyosarcoma arising in the proximal part of the right tibia of a 38-year-old man. The diagnosis was confirmed by immunohistochemistry (positivity of tumor cells for alpha smooth muscle actin, HHF 35, desmin and vimentin). To the best of our knowledge, this is the 49th documented case of primary leiomyosarcoma of bone outside the facial skeleton. This exceptional tumor arises more commonly in adults (mean age: 53 years) and in the long bones of lower limbs, near the knee. The most frequent symptom is pain with or without swelling or fracture. Radiological findings invariably consist of a non specific osteolytic lesion. Although their histological appearance does not differ from that of extraosseous leiomyosarcomas, their diagnosis is difficult and often requires immunohistochemical and/or ultrastructural study. From a practical point of view, the diagnosis of primary leiomyosarcoma of bone also requires an intensive review of the case history and of previous pathology. This is necessary in order to eliminate an extraosseous primary site (mainly in uterus, gastrointestinal tract and soft tissues). As well as clinicopathological features, modes of treatment and results are also reviewed.