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P Roussouly

Publications and source records attributed to P Roussouly.

12 recordsLinked to original sources
PubMed2005

A variability study of computerized sagittal spinopelvic radiologic measurements of trunk balance.

OBJECTIVE: The accurate measurement of spinal and pelvic alignment in the sagittal plane is of prime importance for various disorders. Pelvic incidence (PI) is a fundamental anatomic parameter that is specific and constant for each adult individual and is related to pelvic orientation as well as to the size of lumbar lordosis (LL). It is the summation of the sacral slope (SS) and pelvic tilt (PT), two position-dependent variables that determine pelvic orientation in the sagittal plane. The authors have proposed a computer software designed to measure PI, SS, PT, LL, and thoracic kyphosis (TK) on standardized standing lateral digitized x-rays of the spine and pelvis. The purpose of this study was to evaluate the inter- and intraobserver variability of measurements using this software, to determine if it can be used reliably in a clinical environment. METHODS: The standing lateral x-rays of 30 subjects were randomly selected from the database of two medical institutions. The normal population had standard radiographs on which the various pertinent landmarks were marked by one operator prior to digitization, whereas the scoliotic population had digital radiographs that obviated the need for prior marking of landmarks. Four individuals measured all variables on the 30 x-rays on two occasions, with a 15-day interval between the two sessions. Statistical analysis was done with intraclass correlation coefficients (ICCs). RESULTS: The ICC measured within observers was between 0.93 and 0.99, whereas the ICC between observers varied between 0.92 and 0.99. The variations observed were similar for normal and scoliotic subjects, and prior marking of the x-rays had no significant influence. CONCLUSION: We conclude that the variability of measurements with this method is lower than with similar radiologic measures done manually and that the use of this software can be recommended for future clinical and research studies of spinopelvic sagittal balance.

Adult↗
PubMed2003

[Geometrical and mechanical analysis of lumbar lordosis in an asymptomatic population: proposed classification].

PURPOSE OF THE STUDY: The main objective of this study was to describe the morphology and the mechanism underlying the organization of lumbar lordosis in terms of position and shape of the pelvis. A classification of lumbar lordosis was proposed based on the orientation of the sacral plane. MATERIAL AND METHODS: One hundred sixty asymptomatic young adult volunteers were x-rayed in a standardized standing position. A dedicated software was used for analysis of the spine and pelvis. The pelvic parameters were: pelvic incidence, sacral slope, pelvic tilt. The point separating thoracic kyphosis and lumbar lordosis was called the inflexion point. Lumbar lordosis was bounded by the sacral plate and the inflexion point. At the apex, the lumbar curve was divided into two tangent arcs of circle, quantified by an angle and the number of included vertebrae. The lower arc was geometrically equal to the sacral slope. Regarding the vertical line, a lordosis tilt angle was drawn between the inflexion point and the frontal limit of the sacral plate. RESULTS: The value of the lumbar lordosis was very variable. The best correlation was between lumbar lordosis and sacral slope, then between sacral slope and pelvic incidence. The upper arc of a circle remained constant while the lower arc changed with sacral slope. Good correlations were found between the sacral slope and the position of the apex and between sacral slope and lordosis tilt angle. DISCUSSION AND CONCLUSION: Regarding sacral slope, lumbar lordosis can be classified into four types. When the sacral slope is low, lumbar lordosis can either be both short and curved with a low apex and a backward tilt (type 1) or both long and flat with a higher position of the apex (type 2). When the sacral slope increases, lumbar lordosis increases in angle and number of vertebrae with an upper apex, with a progressively forward tilt (types 3 and 4). Depending on the shape and position of the pelvis, and because of the relation between sacral slope and pelvic tilt, the morphology of lumbar lordosis could be the main mechanical cause of degenerative diseases of the lumbar spine.

Adult↗
PubMed2002

Sagittal morphology and equilibrium of pelvis and spine.

A prospective analysis of the sagittal profile of 100 healthy young adult volunteers was carried out in order to evaluate the relationship between the shape of the pelvis and lumbar lordosis and to create a databank of the morphologic and positional parameters of the pelvis and spine in a normal healthy population. Inclusion criteria were as follows: no previous spinal surgery, no low back pain, no lower limb length inequality, no scoliotic deviation. For each subject, a 30 x 90-cm sagittal radiograph including spine, pelvis and proximal femurs in standing position on a force plate was performed. The global axis of gravity was determined with the force plate. Each radiograph was digitized using dedicated software. The spinal parameters registered were values for thoracic kyphosis and lumbar lordosis. The pelvic angles measured were: pelvic incidence, sacral slope and pelvic tilt. The global axis of gravity was on average 9 mm anterior of the center of the femoral heads. The anatomic parameter of pelvic incidence angle varied from 33 degrees to 85 degrees (mean: 51.7 degrees, SD: 11 degrees). The average lumbar lordosis was 46.5 degrees. The average thoracic kyphosis was 47 degrees. We found a statistical correlation between incidence angle and lumbar lordosis (r=0.69, P<0.001) and between sacral slope angle and lumbar lordosis (r=0.75, P<0.001). Spine and pelvis balance around the hip axis in order to position the gravity line over the femoral heads. We propose a scheme of sagittal balance of the standing human body.

Adult↗
PubMed1991

Investigation of glycosylation processes in mitochondria and microsomal membranes from human skeletal muscle.

Glycoconjugates are directly involved in major skeletal muscle functions. As little is known about glycosylation processes in muscle, we investigated glycoconjugate synthesis in subcellular fractions from human skeletal muscle tissue. Mitochondria and microsomal membranes were prepared from muscle biopsies by thorough mechanical disruption and differential centrifugations. This procedure resulted in the isolation of intact mitochondria (1 mg protein/g muscle) and of a microsomal fraction (1.5 mg protein/g muscle). Glycosyltransferases were studied in both subcellular fractions using either dolichylmonophosphate as a polyprenic acceptor or chemically modified fetuin as a glycoprotein substrate. Our results provide evidence for high rates of glycosylation in muscle. The highest activities were obtained with GDP-mannose: dilichylmonophosphate mannosyltransferase, a key enzyme in glycosylation process (220 pmol/mg per h in mitochondria and 1,550 pmol/mg per h in microsomal membranes). Substantial individual variations were observed for dolichol pathway glycosyltransferases but low individual variations were found for glycosyltransferases involved in maturation of glycoproteins. The role which glycosylation defects may play in muscle dysfunction has yet to be defined.

Adolescent↗
PubMedDate not supplied

[Spinal osteoblastoma. Report of 8 cases].

The authors studied the special features of the vertebral location of this benign tumour of osteoblastic origin in eight cases of spinal osteoblastoma. Clinically, neurological complications are frequently present and scolioses may arise and persist after treatment; radiologically, new imaging techniques enable the limits of the tumour to be assessed with greater accuracy with respect to the neighbouring bone and their relationship to the components of the vertebral canal; surgically, there are difficulties specific to this location raised by the proximity of nervous components, and also by the vertebral destabilization entailed by the considerable bone involvement. Anatomicopathological diagnosis remains difficult, particularly in the case of osteoid osteoma.

Adolescent↗