[Femoroacetabular impingement. Clinical and radiological diagnostics]. / Femoroazetabuläres Impingement. Klinische und radiologische Diagnostik.

A systematic approach to the examination of the hip region is mandatory to identify patients with femoroacetabular impingement. The patients' age, history, and physical examination may lead to the correct diagnosis. Plain radiographs are the imaging modality of first choice. In addition to obvious findings, more subtle changes such as loss of offset at the head-neck transition or acetabular retroversion have to be assessed. For correct analysis, a high quality of the images must be ensured. Therefore, knowledge of the technique used to take the pictures seems essential. With three-dimensional reconstructed computed tomography, asphericities of the head-neck junction or retroversion of the acetabulum may be visualized. In addition to the accurate demonstration of the head-neck junction, magnetic resonance imaging is particularly suitable to reveal pathological conditions of soft tissues such as articular cartilage or labral lesions.

Radiographic analysis of fusion progression following one-level cervical fusion with or without plate fixation.

BACKGROUND: Anterior cervical discectomy and fusion (ACDF) using bone graft or a cage with plate fixation is an accepted technique for the treatment of symptomatic degenerative disc disease. It is, however, debatable whether a plate is really necessary to increase the progress of fusion. Thus, the aim of this randomized and controlled prospective study was to evaluate whether ACDF with a cage and anterior plate fixation results in a greater progress of fusion compared with ACDF using a stand-alone cage. METHODS: 37 candidates for ACDF were treated either with a stand-alone cage (study group) or with a cage+plate fixation (control group). 19 patients were randomized to be stabilized with a stand-alone cage and 18 patients were treated with a cage and additional anterior plate fixation. The progress of cervical fusion over time was compared by radiostereometric analysis (RSA). Follow-up examinations pre- and postoperatively were done using the Visual Analogue Scale (VAS) for neck and arm pain. Radiographic assessment of fusion using an RSA-control was done after one, six and twelve weeks, as well as after six months, and one and two years postoperatively. Mann-Whitney test for unpaired values was used to determine the statistical differences in residual intervertebral motion. RESULTS: Three-dimensional analysis of segmental motion (left-right, cranio-caudal, and posterior-anterior) did not reveal any statistical differences between both groups at any examination time postoperatively ( P>0.05). The VAS score did not differ between the groups ( P>0.05). CONCLUSION: Anterior plate fixation did not demonstrate an improvement in the progress of fusion in one-level ACDF.

Inactivation of the CDKN2A and the p53 tumour suppressor genes in external genital carcinomas and their precursors.

BACKGROUND: p53 has been extensively studied in external genital carcinoma (EGC), and is frequently inactivated, but little is known about the role of the CDKN2A tumour suppressor gene in the oncogenesis of EGC. OBJECTIVES: To investigate the role of CDKN2A and p53 in the pathogenesis of EGCs and their precursor lesions vulval intraepithelial neoplasia (VIN3), penile intraepithelial neoplasia and lichen sclerosus (LS). METHODS: By means of CDKN2A and p53 mutation screening (single-strand conformational polymorphism analysis and sequencing), methylation analysis of alternative CDKN2A promoters (methylation-specific polymerase chain reaction) and p53 immununochemistry, we analysed eight invasive EGCs (five from vulva and three from penis) and 25 precancerous lesions (two undifferentiated VIN3 and 23 vulval/penile lesions of LS) from 33 patients. RESULTS: p53 mutations (mainly transversions) and CDKN2A mutations (including one hot spot) were present in 75% and 50% of invasive tumours, respectively, but were absent in all precancerous lesions. Remarkably, all CDKN2A-mutated tumours also harboured a p53 mutation. CDKN2A or p53 mutations were observed more frequently in LS-derived EGCs than in human papillomavirus-derived EGCs (P = 0.053). A positive anti-p53 staining, but without p53 mutations, was also detected in 30% of LS lesions, suggesting a p53 stabilization in response to inflammation and carcinogenic insult. Methylation of p16(INK4a) and p14(ARF) promoters was not a frequent mechanism of CDKN2A inactivation. CONCLUSIONS: Our study shows a high prevalence of co-inactivating mutations of p53 and/or CDKN2A genes in EGC, that seem to occur preferentially in LS-derived tumours and late in oncogenesis.

Disc replacement using Pro-Disc C versus fusion: a prospective randomised and controlled radiographic and clinical study.

Anterior cervical discectomy and fusion (ACDF) may be considered to be the gold standard for treatment of symptomatic degenerative disc disease within the cervical spine. However, fusion of the segment may result in progressive degeneration of the adjacent segments. Therefore, dynamic stabilization procedures have been introduced. Among these, artificial disc replacement by disc prosthesis seems to be promising. However, to be so, segmental motion must be preserved. This, again, is very difficult to judge and has not yet been proven. The aim of the current study was to first analyse the segmental motion following artificial disc replacement using a disc prosthesis. A second aim was to compare both segmental motion as well as clinical result to the current gold standard (ACDF). This is a prospective controlled study. Twenty-five patients with cervical disc herniation were enrolled and assigned to either study group (receiving a disc prosthesis) or control group (receiving ACDF, using a cage with bone graft and an anterior plate.) Radiostereometric analysis was used to quantify intervertebral motion immediately as well as 3, 6, 12 and 24 weeks postoperatively. Further, clinical results were judged using visual analogue scale and neuro-examination. Cervical spine segmental motion decreased over time in the presence of disc prosthesis or ACDF. However, the loss of segmental motion is significantly higher in the ACDF group, when looked at 3, 6, 12 and 24 weeks after surgery. We observed significant pain reduction in neck and arm postoperatively, without significant difference between both groups (P > 0.05). Cervical spine disc prosthesis preserves cervical spine segmental motion within the first 6 months after surgery. The clinical results are the same when compared to the early results following ACDF.

[Radiological examination of the hip. Analysis of standard projections]. / Radiologische Untersuchung des Hüftgelenks. Analyse der Röntgenstandardprojektionen.

Plain radiography of the hip joint is the imaging modality of first choice. The standard projections are an anteroposterior view of the whole pelvis and a lateral view of the involved hip. Depending on the suspected pathology, different lateral projections are used such as the Lauenstein view, a false profile view, or a lateral cross-table view. Additional projections may be helpful in special indications. For correct analysis and interpretation, the radiographs need to be checked for adequate orientation and exposure. The orthopedic surgeon has to be familiar with the imaging technique of each radiograph and its normal appearance in order to assess the orientation of the pelvis during exposure and to detect even subtle pathology or changes in orientation of the acetabulum or proximal femur.