The authors report on a prospective multicenter study with regard to the operative treatment of acute fractures and dislocations of the thoracolumbar spine (T10-L2). The study should analyze the operative methods currently used and determine the results in a large representative collective. This investigation was realized by the working group "spine" of the German Trauma Society. Between September 1994 and December 1996, 682 patients treated in 18 different traumatology centers in Germany and Austria were included. Part 2 describes the details of the operative methods and measured data in standard radiographs and CT scans of the spine. Of the patients, 448 (65.7%) were treated with posterior, 197 (28.9%) with combined posterior-anterior, and 37 (5.4%) with anterior surgery alone. In 72% of the posterior operations, the instrumentation was combined with transpedicular bone grafting. The combined procedures were performed as one-stage operations in 38.1%. A significantly longer average operative time (4:14 h) was noted in combined cases compared to the posterior (P < 0.001) or anterior (P < 0.05) procedures. The average blood loss was comparable in both posterior and anterior groups. During combined surgery the blood loss was significantly higher (P < 0.001; P < 0.05). The longest intraoperative fluoroscopy time (average 4:08 min) was noticed in posterior surgery with a significant difference compared to the anterior group. In almost every case a "Fixateur interne" (eight different types of internal fixators) was used for posterior stabilization. For anterior instrumentation, fixed angle implants (plate or rod systems) were mainly preferred (n = 22) compared to non-fixed angle plate systems (n = 12). A decompression of the spinal canal (indirect by reduction or direct by surgical means) was performed in 70.8% of the neurologically intact patients (Frankel/ASIA E) and in 82.6% of those with neurologic deficit (Frankel/ASIA grade A-D). An intraoperative myelography was added in 22% of all patients. The authors found a significant correlation between the amount of canal compromise in preoperative CT scans and the neurologic deficit in Frankel/ASIA grades. The wedge angle and sagittal index measured on lateral radiographs improved from -17.0 degrees and 0.63 (preoperative) to -6.3 degrees and 0.86 (postoperative). A significantly (P < 0.01) stronger deformity was noted preoperatively in the combined group compared to the posterior one. The segmental kyphosis angle improved by 11.3 degrees (8.8 degrees with inclusion of the two adjacent intervertebral disc spaces). A significantly better operative correction of the kyphotic deformity was found in the combined group. In 101 (14.8%) patients, intra- or postoperative complications were noticed, 41 (6.0%) required reoperation. There was no significant difference between the three treatment groups. Of the 2264 pedicle screws, 139 (6.1%) were found to be misplaced. This number included all screws, which were judged to be not placed in an optimal direction or location. In seve...

We examined 58 children aged 1-16 years with various forms of osteogenesis imperfecta (OI). Congenital cardiac malformations were diagnosed in 4 children (valvular aortic stenosis, 2 with atrial septal defect II, Fallot Tetralogy). Two additional children developed holosystolic mitral valve prolapse and regurgitation. Children suffering from a severe clinical course (type III according to the Sillence classification) showed aortic root dilatation (28%) and increased septal (40%) and posterior left ventricular wall thickening (68%) on initial evaluation. All three parameters were significantly correlated to body surface area. Kidney stones and renal papillary calcifications were detected in 4 children. Cardiovascular abnormalities and nephrolithiasis may be important extraskeletal manifestations of childhood OI.

Both posterior and anterior procedures of stabilization are used for operative immobilization of unstable functional units of the cervical spine. The primary stabilizing effect of each procedure was examined and the two were compared in an experimental study. To this end the functional units C-5 and C-6 were removed from ten fresh cervical spines, the discoligamentous structures being preserved, and C-6 was embedded in methacrylate. As a result of a tensile force in a vertical direction applied to the base of the spinous process of C-5, a flexion bending load was introduced into the unit, the main component of which was measured with the aid of one vertical- and two horizontal-displacement transducers. The respective tilting angle alpha and the translation were calculated on the basis of these values. Each individual functional unit was measured with and without the discoligamentous lesion. This posterior instability was then stabilized with an H-plate, a hook plate, sublaminar wiring, and various combinations of these. Our results lead to the following clinically relevant conclusions: With isolated posterior instability, posterior fixation with the hook plate appears to bring about exercise stability. With complete discoligamentous instability, the combined procedures certainly produce exercise stability, from a biomechanical point of view, the posterior hook, plate alone being capable of guaranteeing secure fixation. Exclusive posterior wiring with complete discoligamentous instability may, without external immobilization, result in permanent subluxation in the functional unit. Exclusive anterior H-plate fixation with complete discoligamentous instability requires additional external immobilization in the postoperative stage in order to prevent flexion.

We analysed the composition of compact bone from 30 patients suffering from various forms of osteogenesis imperfecta (OI). Collagen and total protein content per cell of controls increased with the age of the donors, but were generally low in OI. In fibroblast cultures controls had a maximum of collagen synthesis between 2 and 9 years of age, an observation which was not seen in OI cells. In bone collagen both OI type II patients showed overhydroxylation of lysyl residues as did some patients with OI type III (25%) and OI type IV (33%). The collagen of OI type I patients was never found to be overmodified. In controls, collagen III was found exclusively during fetal time while it was present in significant amounts in bone tissue of all types of OI. The proportion of collagen V was somewhat higher in OI bones (about twice) than in controls. Our data suggest that the normal increase of collagen synthesis is defective in patients with OI. Perhaps some of these changes are due to specific molecular defects in collagen while others may be due to defective regulation of the maturation process.

We analyzed tissue and cells from a stationary and a rapidly growing hyperplastic callus from a patient with osteogenesis imperfecta (OI) type IV and compared the results with those of compact bone and skin fibroblasts of an age-matched control.Collagen and protein contents per cell were low in the callus tissues and collagen I and III were overmodified as evidenced by an elevated level of hydroxylysine. The degree of lysyl hydroxylation was highest in those regions that appeared most immature by histological examination. Lysyl hydroxylation approached normal levels in collagen from the stationary callus and from the center of the growing callus. Overmodification of collagen was not seen in compact bone or cell cultures (neither skin fibroblasts nor callus cells) from the patient. Elevation of hydroxylysine in collagen from OI patients is generally attributed to mutations that delay triple helix formation. Our observations suggest that the varying degree of collagen modifications may occur in consequence of regulatory mechanisms during bone development and tissue repair. These mechanisms may be defective in some patients with 01 as seen in this case with hyperplastic callus formation.