Advanced template matching method for estimation of intervertebral kinematics of lumbar spine

Accuracy and repeatability of quantitative fluoroscopy for the measurement of sagittal plane translation and finite centre of rotation in the lumbar spine

“…The suggestion that it might be used to measure stability has therefore also not generally been taken up [14]. However, the present study has shown that despite the use of continuous motion data, as is necessary in patient studies, greater accuracy was achieved for determining the FCR (average error 0.3mm x , 0.4mm y ) than was found in a previous study with such a specimen that used stepped rotation positions (average error 2mm) [15]. Diagnostic advances in spine biomechanics have also been made using kinetic MRI [37][38][39][40][41] and SPECT-CT imaging [42,43].…”

“…233 Table 3 The accuracy of techniques for radiographic measurement of intervertebral kinematics has been determined using calibration models for roentgen stereophotogrammetry, (which although highly invasive, is sometimes considered the gold standard), biplanar radiography and QF [10,15,27,28]. In this study, idealised conditions were also avoided by degrading the images with animal soft tissue and in the upright position, although It is not uncommon for such studies to be undertaken with no loading or in an animal model with no tissue degradation [16,29,30] In this study, we compensated for radiographic image distortion using distortioncompensated roentgen analysis and used an image intensifier that incorporated automatic distortion correction [21].…”

A continuous description of intervertebral motion by means of spline interpolation of kinematic data extracted by videofluoroscopy

“…Sagittal fluoroscopic image sequences of three healthy subjects lying on a motorized table undergoing passive lumbar motion, already utilized in previous studies (Cerciello et al, 2011;Kondracki, 2001), were analyzed (Fig. 1).…”

“…A gradient cross-correlation template matching was utilized to locate a selected vertebra on each image of the videofluoroscopic sequence (Cerciello et al, 2011). This automated method provides a more precise description of intervertebral motion with respect to manual marking (Kondracki, 2001) and other automated procedures (Bifulco et al, 2001;Muggleton and Allen, 1997;Zheng et al, 2004).…”

“…Unlike functional flexion-extension radiography, videofluoroscopy provides a continuous screening of specific spinal tracts during patient's motion with an acceptable X-ray dose. Intervertebral kinematic estimation can be, however, affected by large errors due to the low quality of fluoroscopic images, especially for lumbar spine sequences because of the larger amount of soft tissue involved (Bifulco et al, 2001;Cerciello et al, 2011;Muggleton and Allen, 1997). Both needs to reduce measurement errors and to obtain a continuous-time representation of motion extracted by videofluoroscopy can be met through the application of smoothing spline to kinematic data.…”