Validity of rotational laxity coupled with anterior translation of the knee: A cadaveric study comparing radiostereometry and the Rotab®.

Background: In current practice, anterior cruciate ligament (ACL) tears can be diagnosed using several devices to measure anterior tibial translation and rotational knee laxity, but these measures are never collected together. The Rotab®, which yields simultaneous measurements of anterior tibial translation and passive lower limb rotation under stress, would therefore be advantageous in current practice, but its reliability has never been tested.

Aim Of Study: To evaluate the accuracy and reliability of the Rotab® compared to the reference system, radiostereometric analysis (RSA).

Is determination of the hip rotation center during computer-assisted surgery influenced by the pinless femoral sensor attachment method? An in vitro preliminary study comparing osseous pin fixation.

Introduction: Computer-assisted surgery improves the positioning of hip prostheses but requires use of transosseous pins requiring a complementary approach exposing the patient to rare but at times serious complications. The use of sensor arrays attached to the skin could advantageously replace pins provided that comparable results are obtained, but their validity has not yet been assessed. We conducted a prospective in vitro study to: measure the possible error of a cutaneous versus transosseous fixation to determine the hip rotation center (HRC) position and determine the inter- and intraobserver reproducibility of the cutaneous versus the transosseous fixation.

Validation of the in vivo volumetric wear measurement for total knee prostheses in model-based RSA.

Implant failure related to polyethylene wear remains an important issue in total knee arthroplasty. Polyethylene wear is usually assessed in vivo by measuring the remaining insert thickness on X-ray images of the knee. To reflect the amount of wear debris more accurately, a 3-dimensional overlap measurement has been suggested, which is based on implant component models which are matched on calibrated stereo X-ray images using model-based roentgen stereophotogrammatic analysis.

Oral thromboprophylaxis following total hip replacement: the issue of compliance.

Introduction: Thirty-five to 40 days' thromboprophylaxis is recommended following total hip replacement (THR). Low molecular weight heparin (LMWH) injected by a health professional ensures good compliance. Compliance with recent oral anticoagulants has not been precisely assessed.

Total knee arthroplasty three-dimensional kinematic estimation prevision. From a two-dimensional fluoroscopy acquired dynamic model.

Introduction: To determine six-degree of freedom of total knee arthroplasty kinematics (TKA), optimized matching algorithms for single fluoroscopic image system may be used. Theoretical accuracy of these systems was reported. Nevertheless, all reports were done under idealized laboratory experimental conditions.

Dual mobility hip arthroplasty wear measurement: Experimental accuracy assessment using radiostereometric analysis (RSA).

Introduction: The use of dual mobility cups is an effective method to prevent dislocations. However, the specific design of these implants can raise the suspicion of increased wear and subsequent periprosthetic osteolysis.

Hypothesis: Using radiostereometric analysis (RSA), migration of the femoral head inside the cup of a dual mobility implant can be defined to apprehend polyethylene wear rate.