Custom made acetabular prosthesis are a valid option for the reconstruction after the resection of pelvic tumors. They should guarantee a stable and reliable reconstruction for the expected survival of the patient. Nevertheless in many cases periacetabular metastatic lesions have been compared to high grade (IIIA-B) Paprosky defects, but treated with low or intermediate longevity implants. Some complex post-traumatic scenarios or total hip arthroplasty (THA) multiple failures need a reconstruction according to oncologic criteria to fill in the huge defect and to obtain an acceptable function. The aim of the study is to compare 3D custom-made implants for tumors and for THA failures. Three custom-made implants after tumor resection (group A: 1 chondroblastic osteosarcoma, 1 bifasic synovialsarcoma, 1 high grade chondrosarcoma) were evaluated and compared to 3 acetabular complex reconstructions after non-oncologic bone defect (group B: 3 cases of aseptic loosening after at least 2 revisions). All the implants were case-based designed, 3D printed, and realized with porous or trabecular surfaces on a Titanium base prosthesis. Age range 16–70 ys in oncologic patients and 60–75 ys in non-oncologic patients. The bone defect to be reconstructed after tumor resection was classified according to Enneking zones (1 type 1-2-3 resection, 1 type 2 resection, 1 partial type 2 resection). Non-oncologic cases were comparable in term of remaining bone stock and classified according to Paprosky classification for acetabular defects as 1 type IIIA an 2 type IIIB. Complications, MSTS functional score, necessity of walking-aids were evaluated at minimum follow up of 1 year.Introduction and Purposes
Materials and Methods
The purpose of this study is to identify the optimal amount of knee flexion required to drill the femoral tunnel in ACL reconstruction using the transtibial technique in order to ensure the correct alignment between the femoral tunnel and the interference screw.
This study identifies a mathematical formula for the optimal amount of knee flexion required to drill the femoral tunnel in ACL reconstruction using the transtibial technique in order to ensure the correct alignement between the femoral tunnel and the interference screw.
The failure rate of peritrochanteric fracture implants ranges from 5 to 20 % The aim of the present preliminary study is to evaluate the relationship between Singh index (SI), and failure of internal fixation (cut-out), examining bone mechanical properties from ex-vivo human femoral heads. The failure rate of peritrochanteric fracture implants ranges from 5 to 20 % The aim of the present preliminary study is to evaluate the relationship between Singh index (SI), and failure of internal fixation (cut-out), examining bone mechanical properties from ex-vivo human femoral heads. From a methodological point of view we decided to use SI on the basis of previous literature,, our data seems not to be influenced by the use of this methodological approach. >
Three load speeds were set: 3, 10, 500 mm/min resulting values of BW/s were compared with Davy and Bergmann ones (obtained with instrumented prosthesis), and test validity was confirmed. In conclusion our data demonstrated that: cut out phenomenon occurs for lower mechanical load in femoral heads of patients with lower SI.