Measuring extension of the lumbar-pelvic-femoral complex with the EOS® system.

INTRODUCTION: Sagittal balance of the coxofemoral joint in standing position and its extension capacity determine hip/spine adaptation, especially in relation to pelvic retroversion, which may be age-associated or follow either spinal arthrodesis or vertebral osteotomies. The concept of extension reserve is essential for assessing posterior hip impingement. The global visualization of the lumbar-pelvic-femoral complex obtained by EOS(®) imaging enables this sagittal analysis of both the subpelvic region and lumbar spine by combining the reference standing position and the possibility of dynamic tests. MATERIALS AND METHODS: We studied 46 patients and their 92 hips. The EOS(®) radiography was performed in neutral standing position and with one foot on a step, alternately the right and left feet. Pelvic incidence, sacral slope, pelvic version, and femoral version were measured twice by two operators. The global extension reserve (GER) was defined by the sum of the intrinsic extension reserve (allowed by the hips, IER) and the extrinsic extension reserve (allowed by the spine, EER). The IER for each hip corresponds to the difference in the sacrofemoral angle (SFA) for each of the two positions. The EER was measured by the difference in the sacral slope. A descriptive study was performed, together with studies of inter- and intra-observer reproducibility, right/left symmetry, and an analysis according to age, sex, and BMI. RESULTS: The mean femoral version in the reference position was 11.7° (SD 14.3°). The reproducibility of the SFA measurement was statistically verified. The IER (mean 8.8°), EER (mean -0.7°), and GER (mean 8.2°) all differed significantly between the two sides for each patient and were not associated with age, sex, or BMI. DISCUSSION: The femoral axis is not perpendicular to the ground in neutral position, contrary to the conventional view of this position. The measurements proposed for dynamic sagittal analysis of the hip are reproducible and make it possible to identify the IER within the GER of the spinal-pelvic-femoral complex. CONCLUSION: The assessment of the lumbar-pelvic-femoral complex by EOS imaging makes it possible to define the intrinsic and extrinsic extension reserves to describe the reciprocal adaptive capacities of the hips and spine. LEVEL OF EVIDENCE: IV.

Measuring femoral and rotational alignment: EOS system versus computed tomography.

INTRODUCTION: Computed tomography (CT) is currently the reference standard for measuring femoral and tibial rotational alignment. The EOS System is a new biplanar low-dose radiographic device that allows 3-dimensional lower-limb modelling with automated measurements of femoral and tibial rotational alignment (torsion). HYPOTHESIS: Femoral and tibial torsion measurements provided by the EOS System are equivalent to those obtained using CT. MATERIALS AND METHODS: In a retrospective analysis of 43 lower limbs in 30 patients, three senior radiologists measured femoral and tibial torsion on both CT and EOS images. Agreement between CT and EOS values was assessed by computing Pearson's correlation coefficient and interobserver reproducibility by computing the intraclass correlation coefficient (ICC). RESULTS: Femoral torsion was 13.4° by EOS vs. 13.7° by CT (P=0.5) and tibial torsion was 30.8° by EOS vs. 30.3° by CT (P=0.4). Strong associations were found between EOS and CT values for both femoral torsion (P=0.93) and tibial torsion (P=0.89). With EOS, the ICC was 0.93 for femoral torsion and 0.86 for tibial torsion; corresponding values with CT were 0.90 and 0.92. DISCUSSION: The EOS system is a valid alternative to CT for lower-limb torsion measurement. EOS imaging allows a comprehensive evaluation in all three planes while substantially decreasing patient radiation exposure. LEVEL OF EVIDENCE: Level III, case-control.

Tibiofibular torsion from the fetal period until birth.

The anatomic findings of Le Damany and Dupuis are still valuable as a reference. However, their measurement of tibial torsion does not correspond to clinical conditions. In fact, the torsion of the tibiofibular functional unit corresponds to the angle between the transverse axis of the proximal tibial epiphyseal plate and the axis through the middle of both malleoli. A comparative morphologic, radiologic, computerized axial tomographic and anatomic study performed on 50 fetuses with this definition has shown different results. Tibiofibular torsion was in the clear lateral position from the beginning of the fetal period, with a positive gradient at birth.

[Muscle metastases: ultrasonic and x-ray computerized tomographic aspects. Apropos of 9 cases]. / Les métastases musculaires: aspects échographiques et tomodensitométriques. A propos de 9 observations.

Clinical, ultrasound and CT scan examinations were carried out in 9 patients with secondary muscle lesions. All muscles can be affected but there was a marked predominance of psoas lesions (6 of the 9 cases). Two contrasting clinical pictures are seen. Secondary muscle tumors can occur during evolution of a known treated cancer (5 of the 9 cases), revealed usually by large, rarely painful, mass. CT scan imaging shows a heterogeneous mass taking up contrast and often partially necrotic, the lesions appearing hypoechogenic or heterogeneous on ultrasound examination. Certain lesions can be totally necrotic. In some cases (4 of the 9 patients) the muscle metastases revealed the presence of a tumor. Symptomatology may be atypical and lead to a delay in diagnosis. Fine needle puncture biopsy can detect the secondary origin of the muscle lesion and also the primary tumor site (4 out of 9 cases), bronchopulmonary and colon cancer predominating. Images are however non-specific and in the absence of NMR imaging the muscle or lymph node metastases can be confused, although this has no practice consequences since treatment is identical.

[Complications of the treatment of renal calculi by extracorporeal lithotripsy. Prospective evaluation of 80 treated kidneys]. / Complications du traitement de la lithiase rénale par lithotriptie extracorporelle. Evaluation prospective de 80 reins traités.

The acute effects of extracorporeal shock wave lithotripsy (ESWL) on morphology and function of the kidney were prospectively evaluated by abdominal radiography, ultrasonography and contrast-enhanced computed tomography, in 80 treated kidneys. Two types of complications were demonstrated: 1. Obstruction of the ureter by stone fragments in 25% of cases. Relief procedures became necessary in 5 patients (6% of the 80 cases). 2. Limited injuries of the kidney and perirenal spaces in 44% of cases: parenchymatous abnormalities 17.5%; subcapsular hematoma 12.5%; perirenal fluid collection 24%. No treatment was necessary and morphologic abnormalities disappeared in one or two months post-ESWL. Severe ureteral obstruction after ESWL seems to be related to stone size. No definitive evidence that kidney's injury was related to the number of shock waves applied to the kidney was found.

[X-ray computed tomography in the course of mediastinitis after sternostomy for heart surgery]. / Apport de la tomodensitométrie dans l'évolution des médiastinites après sternotomie pour chirurgie cardiaque.

Results are reported of a prospective study of 79 CT scan examinations in 50 patients who had undergone sternotomy for cardiovascular surgery. In 69 cases the examination was conducted during the course of a progressive postoperative mediastinitis treated surgically. Mediastinitis was confirmed in 13 cases, including 12 relapses. In 2 cases the CT scan image was normal (2 false negatives) whereas mediastinal drains had been inserted. The CT scan image of mediastinitis shows mainly hypodense fluid collections (0 to 16 UH) in anterior mediastinum or between sternotomy borders (8 of 13 cases). But this type of image, detected 11 times in the absence of recurrence (favorable course), can result from a residual serous collection after ablation of drains. In 8 cases, a CT scan-guided puncture (7 cases) or one under ultrasound control (1 case) eliminated recurrence. The CT scan imaging also allowed diagnosis of 5 cases of osteitis, confirmed surgically. These findings indicate the definite interest of CT scan imaging in postoperative follow-up review of median sternotomies. It appears to be particularly indispensable for surveillance of surgically treated mediastinitis, because of the serious consequences of relapses and the often clinically silent chronic bone lesion. However, the possibility of residual serous collections emphasizes the importance of the clinical context and should lead to guided puncture investigation in doubtful cases.

[Osseous hydatidosis of the pelvic girdle. Contribution of computerized tomography and ultrasonics. Apropos of 3 cases]. / Hydatidose osseuse de la ceinture pelvienne. Apport de la tomodensitométrie et de l'échographie. A propos de 3 observations.

Three cases of bone hydatidosis of pelvis with invasion of soft tissues provided data on the effectiveness of CT scan and ultrasound imaging for diagnosis, evaluation of extension and follow up surveillance of this affection. Two of the three patients treated medically were followed up by review CT scan and ultrasound examinations. The two techniques were found to be effective for detecting recurrence and for surveillance of hydatid lesions of soft tissues during medical therapy.

[Visualization of the scapholunate space. Description of a simple radiologic image]. / Visualisation de l'interligne scapho-lunarien. Description d'une incidence radiologique simple.

Scapho-lunate diastasis is a radiologic criterium of carpal instability. This paper stresses on the importance of producing an X-ray beam that will be parallel to the scapho-lunate joint and describes a simple radiologic positioning that will be a useful complement to the standard views. This view could be associated with the usual static as well as dynamic radiographs.