Internal lengthening devices in the femur lengthen along the anatomical axis, potentially creating lateral shift of the mechanical axis. We aimed to determine whether femoral lengthening along the anatomical axis has an inadvertent effect on lower limb alignment. Isolated femoral lengthening using the Intramedullary Skeletal Kinetic Distractor was performed in 27 femora in 24 patients...

PURPOSE To evaluate the discrepancy between the anatomical axis of the distal femur of Japanese patients and the stem position of 5 types of femoral components. METHODS Lateral radiographs of 12 men and 88 women aged 31 to 83 (mean, 59) years with rheumatoid arthritis were evaluated. The discrepancy between the anatomical axis of the distal femur and the stem position of 5 types of femoral co...

BACKGROUND Evaluating the landmarks for rotation of the distal femur is a challenge for orthopedic surgeons. Although the posterior femoral condyle axis is a good landmark for surgeons, the surgical transepicondylar axis may be a better option with the help of preoperative CT scanning. The purpose of this study was to ascertain relationships among the axes' guiding distal femur rotational align...

The determination of the instantaneous axis of rotation of human joints has numerous applications. The screw axis can be determined using optical motion capture systems or electromechanical goniometers. In this paper, we introduce a new method for the localization of the instantaneous screw axis in human anatomical joints from the data given by a spatial mechanical goniometer.

OBJECTIVE To carry out an anatomical study of the axis with the use of computed tomography (CT) in children aged from two to ten years, measuring the lamina angle, lamina and pedicle length and thickness, and lateral mass length. METHODS Sixty-four CTs were studied from patients aged 24 to 120 months old, of both sexes and without any cervical anomaly. The measurements obtained were correlate...

Measurement of the stiffness of spinal motion segments is widely used for evaluating the stability of spinal implant constructs. A three-dimensional motion analysis technique has been developed that allows accurate measurement of the relative movement of the vertebral bodies about a well-defined anatomical axis system. The position of marker clusters on each vertebra is tracked using digital in...

OBJECTIVE To define the distal femur rotation pattern in a Brazilian population, correlating such pattern with the one suggested by the arthroplasty instruments, and analyzing the variability of each anatomic parameter. MATERIALS AND METHODS A series of 101 magnetic resonance imaging studies were evaluated in the period between April and June 2012. The epidemiological data collection was perf...

The rotational alignment of the tibia is an unresolved issue in knee replacement. A poor functional outcome may be due to malrotation of the tibial component. Our aim was to find a reliable method for positioning the tibial component in knee replacement. CT scans of 19 knees were reconstructed in three dimensions and orientated vertically. An axial plane was identified 20 mm below the tibial sp...