Hypothermia at neonatal intensive care unit admission was not associated with respiratory disease or death in very preterm infants.

AIM: This study investigated the association between hypothermia and respiratory distress syndrome (RDS), bronchopulmonary dysplasia (BPD) or death in very preterm infants admitted to a Danish neonatal intensive care unit (NICU). METHODS: We studied 675 infants born at Aalborg University Hospital before 32 weeks and admitted to the NICU from April 1997 to December 2011. Hypothermia was defined as a core temperature of <36.5°C on admission. The primary outcome was severe RDS or death within the first three days of life, and the secondary outcome was BPD or death before 36 postmenstrual weeks. The multivariable logistic regression was adjusted for early-onset infection, gestational age, Apgar score, sex, treatment year and birth weight. RESULTS: Infants with hypothermia had a twofold increase (OR) in the odds for RDS or death (2.03), but the adjusted OR was not statistically significant (1.36). They also demonstrated a twofold increase (OR) in the odds for BPD or death (2.28), but again the adjusted OR was not statistically significant (1.03). CONCLUSION: After adjusting for confounders, we found that the association between hypothermia on admission to the NICU and RDS or death, or BPD or death was statistically insignificant.

[Osteochondritis Dissecans of the Talus - A Critical Review]. / Osteochondrosis dissecans tali ­ eine kritische Übersicht.

The etiology remains unclear. Mechanical factors seem to play an important role. Most histologies report clefts between the cartilage and bone and necrotic areas. Several classifications have been published based on observations from imaging techniques or on intraoperative findings. Clinical symptoms are unspecific. Imaging techniques are of great importance: X-rays of the ankle joint enable a quick diagnostic overview. MRT is the imaging-technique of choice for diagnosing OCDT-lesions. Regarding treatment, a tremendous number of retrospective publications exist. Only a few are classified as level I or II papers. Patients with open physes and low-grade lesions have good results with conservative therapy. Adults do not profit from a longer conservative procedure. Where surgery is necessary, the procedure depends on the stage of the lesion and on the state of the cartilage. With intact cartilage, retrograde procedures or transchondral drilling are to be favoured. Where the cartilage is damaged, several techniques can be used: while techniques such as drilling and microfracturing, or matrix-associated microfracturing produces repair cartilage, other techniques reconstruct the defect with osteochondral grafts or cell-based procedures such as chondrocyte transplantation. Regarding the outcome, it is difficult to make a precise, scientifically-based recommendation which has been confirmed by more than one prospective study. Only limited recommendations are possible: In juveniles with intact cartilage, initially conservative treatment is indicated. If there is no improvement, conservative invasive techniques such as drilling may help. In adults conservative therapy should be limited to a few weeks. Regarding the surgical treatment options, there is a tendency towards better results with procedures which reconstruct the bone and the cartilage and there is also a trend towards better long-term results when co-morbidities are treated. Severe grades of osteoarthrosis are rare.

Autologous chondrocyte implantation (ACI) for cartilage defects of the knee: A guideline by the working group "Clinical Tissue Regeneration" of the German Society of Orthopaedics and Trauma (DGOU).

BACKGROUND: Autologous chondrocyte implantation (ACI) is an established and well-accepted procedure for the treatment of localised full-thickness cartilage defects of the knee. METHODS: The present review of the working group "Clinical Tissue Regeneration" of the German Society of Orthopaedics and Trauma (DGOU) describes the biology and function of healthy articular cartilage, the present state of knowledge concerning therapeutic consequences of primary cartilage lesions and the suitable indication for ACI. RESULTS: Based on best available scientific evidence, an indication for ACI is given for symptomatic cartilage defects starting from defect sizes of more than three to four square centimetres; in the case of young and active sports patients at 2.5cm(2), while advanced degenerative joint disease needs to be considered as the most important contraindication. CONCLUSION: The present review gives a concise overview on important scientific background and the results of clinical studies and discusses the advantages and disadvantages of ACI. LEVEL OF EVIDENCE: Non-systematic Review.

Percutaneous antegrade scaphoid screw placement: a feasibility and accuracy analysis of a novel electromagnetic navigation technique versus a standard fluoroscopic method.

BACKGROUND: Central screw positioning in the scaphoid provides biomechanical advantages. METHODS: A prospective randomized study of six fluoroscopically guided and six electromagnetically navigated screw (ENS) placements was performed on human cadavers. Accuracy of screw position was determined. Intraoperative fluoroscopy exposure times, readjustments of drilling directions, complete restarts and complications were documented. RESULTS: The ENS method provided a mean time benefit of 7.34 min compared with the standard method and the mean screw length ratio (SLR coronar: ENS 0.96 ± 0.04 mm, SFF: 0.92 ± 0.04 mm, P = 0.065; SLR sagittal: ENS 0.98 ± 0.02 mm, SFF: 0.91 ± 0.04 mm, P = 0.009) and the screw axis deviation angle (AD coronar: ENS 3.33 ± 2.34°, SFF: 10.33 ± 2.58°, P = 0.002; AD sagittal: ENS 2.83 ± 0.98°, SFF: 11.00 ± 6.16°, P = 0.002) were lower. Using the electromagnetic navigation procedure no drilling readjustments or restarts were required, no cortical breach occurred. CONCLUSIONS: Compared with the standard fluoroscopic technique, the ENS method used in this study showed higher accuracy, less complications, required less operation and radiation exposure time.

[New horizons for minimally invasive treatment of acromioklavikular joint injuries]. / Neue Horizonte zur minimal-invasiven Versorgung von Akromioklavikulargelenkverletzungen.

BACKGROUND: A novel radiation-free electromagnetic navigation system (ENS) method was developed and the feasibility and accuracy for transklavikular-transkorakoid drilling procedures were evaluated in an experimental setting. METHODS: In this study ten arthroscopically assisted, electromagnetically navigated transkorakoid-transklavikular drilling procedures with subsequent implantation of two TightRope® (Arthrex, Naples, FL.) devices (anatomical reconstruction) were performed on five human cadavers. Postoperative computed tomography (CT) scan analysis was carried out to determine tunnel placement accuracy. All procedures were performed without fluoroscopy. RESULTS: The mean overall operation time was 28.5 ± 6.6 min. Successful anatomical tunnel placement was achieved in 98.8 %. During the navigated drilling procedure no misguidance of the drill requiring directional readjustments or restarts occurred. No cortical breaches, fractures or complications occurred. CONCLUSION: The electromagnetically navigated transkorakoid-transklavikular drilling procedure used in this study demonstrated high targeting accuracy, required no intraoperative x-ray radiation and was associated with no complications.

[Post-treatment rehabilitation after autologous chondrocyte implantation: State of the art and recommendations of the Clinical Tissue Regeneration Study Group of the German Society for Accident Surgery and the German Society for Orthopedics and Orthopedic Surgery]. / Nachbehandlung bei der autologen Chondrozytentransplantation: Eine Bestandsaufnahme und Empfehlung der AG Klinische Geweberegeneration der DGU/DGOOC.

BACKGROUND: Over the course of the past two decades autologous chondrocyte implantation (ACI) has become an important surgical technique for treating large cartilage defects. The original method using a periostal flap has been improved by using cell-seeded scaffolds for implantation, the matrix-based autologous chondrocyte implantation (mb-ACI) procedure. MATERIAL AND METHODS: Uniform nationwide guidelines for post-ACI rehabilitation do not exist. A survey was conducted among the members of the clinical tissue regeneration study group concerning the current rehabilitation protocols and the members of the study group published recommendations for postoperative rehabilitation and treatment after ACI based on the results of this survey. RESULTS: There was agreement on fundamentals concerning a location-specific rehabilitation protocol (femoral condyle vs. patellofemoral joint). With regard to weight bearing and range of motion a variety of different protocols exist. Similar to this total agreement on the role of magnetic resonance imaging (MRI) for postsurgical care was found but again a great variety of different protocols exist. CONCLUSIONS: This manuscript summarizes the recommendations of the members of the German clinical tissue regeneration study group on postsurgical rehabilitation and MRI assessment after ACI (level IVb/EBM).

[Autologous chondrocyte implantation (ACI) for cartilage defects of the knee: a guideline by the working group "Tissue Regeneration" of the German Society of Orthopaedic Surgery and Traumatology (DGOU)]. / Stellenwert der autologen Chondrozytentransplantation (ACT) in der Behandlung von Knorpelschäden des Kniegelenks - Empfehlungen der AG Klinische Geweberegeneration der DGOU.

Autologous chondrocyte transplantation/implantation (ACT/ACI) is an established and recognised procedure for the treatment of localised full-thickness cartilage defects of the knee. The present review of the working group "Clinical Tissue Regeneration" of the German Society of Orthopaedics and Traumatology (DGOU) describes the biology and function of healthy articular cartilage, the present state of knowledge concerning potential consequences of primary cartilage lesions and the suitable indication for ACI. Based on current evidence, an indication for ACI is given for symptomatic cartilage defects starting from defect sizes of more than 3-4 cm2; in the case of young and active sports patients at 2.5 cm2. Advanced degenerative joint disease is the single most important contraindication. The review gives a concise overview on important scientific background, the results of clinical studies and discusses advantages and disadvantages of ACI.

Management of traumatic spinopelvic dissociations: review of the literature.

PURPOSE: Spinopelvic dissociation is a rare high-energy injury pattern in adults associated with high morbidity and an increased rate of neurological deficits. The purpose of this article is the conception of fracture type-associated treatment recommendations. METHODS: This article is based on our own experience with spinopelvic dissociations and a review of the current literature. RESULTS: Bilateral vertical plus an optional transverse fracture component configures spinopelvic dissociations as "U"- or "H"-shaped, with the result of a spinopelvic dissociation. "Y"-, "T"- or "II"-shaped fractures do not necessarily belong to this entity but can be subsumed to this entity in a wider sense. The surgical treatment of these injuries remains challenging. Initial haemodynamic stabilisation represents the main goal of primary care until definitive treatment can be performed. Anatomical reduction is demanding and even more complex in fracture areas with large comminution. Surgical treatment options depend on the fracture type, including transsacral screws, sacral banding and spinopelvic fixation, plus combinations of these procedures. CONCLUSIONS: Spinopelvic dissociations remain highly complex injuries. "U"- and "H"-shaped fractures usually require triangular fixation, whereas "II"-, "Y"- and "T"-shaped fractures might be sufficiently stabilised with transsacral screws.

Identification of molecular markers for articular cartilage.

OBJECTIVE: The aim of the current study was to identify molecular markers for articular cartilage (AC) that can be used as tools for the quality control of tissue engineered (TE) cartilage. DESIGN: A genome-wide expression analysis was performed using RNA isolated from articular and growth plate (GP) cartilage, both extracted from the knee joints of 6 weeks old minipigs. After confirming the specific expression for selected genes by RT-PCR, these were used as molecular markers for the quality control of TE cartilage. RESULTS: Albeit several known chondrocyte markers were expressed to a similar extent in articular and GP cartilage, our genome-wide expression analysis led us to identify genes being selectively expressed in either GP or articular chondrocytes. These findings led us to perform a RT-PCR expression analysis for the corresponding genes to demonstrate the absence of GP-specific markers in TE cartilage, while common or AC markers were expressed. CONCLUSIONS: Taken together, these results provide important novel insights into chondrocyte biology in general and AC in particular. In addition, it is reasonable to speculate, that some of the identified genes play distinct roles in the regulation of articular chondrocyte differentiation and/or function, thereby raising the possibility that they may serve as targets for non-operative therapies of osteoarthritis (OA).

Long term results after implantation of tissue engineered cartilage for the treatment of osteochondral lesions in a minipig model.

In present study we determined the long term in vivo integration and histological modeling of an in vitro engineered cartilage construct. Tissue engineered autologous cartilagenous tissue was cultured on calcium phosphate cylinders and implanted into osteochondral defects into the femoral condyles in minipigs. Radiological follow-up was performed at 2, 8, 26 and 52 weeks, condyles were harvested 26 and 52 weeks post-implantation. Thickness of cultivated tissue (1.10 +/- 0.55 mm) was comparable to in situ cartilage and cells produced in vitro cartilage specific proteins. In vivo, 26 and 52 weeks post-implantation defects were resurfaced with hyaline-like tissue, the implants were well integrated with no gap at the interface between the engineered neocartilage and the adjacent articular cartilage. Synthesis of type II collagen was detected 26 and 52 weeks after implantation. The modified ICRS score increased from 26 to 52 weeks. Histomorphometric evaluation revealed a decrease in cellularity in tissue engineered cartilage from 2.2-fold of native cartilage after 26 weeks to 1.5-fold after 52 weeks. In conclusion, these findings demonstrate the integration and maturation of tissue engineered cartilage pellets attached on a bone substitute carrier implanted in osteochondral defects over a long time.

[Balloon assisted cement application for stable fixation of pedicle screws in osteoporosis]. / Ballonassistierte Zementaugmentation zur stabilen Pedikelschraubenverankerung bei Osteoporose.

In Germany more than 40,000 patients suffer from osteoporotic vertebral fractures every year. Most of these fractures do not require operative stabilisation. However, if surgical stabilisation is necessary, stable fixation of transpedicular implants will be difficult to obtain. In a case study we report on the possibility of a kyphoplasty-guided technique for stable pedicle screw fixation.

[Osteochondritis dissecans of the knee joint]. / Osteochondrosis dissecans des Kniegelenkes.

Osteochondritis dissecans is a disorder with a prevalence of 0.01 to 0.06 %. Men between 16 and 36 years of age are most commonly affected by it. In the western hemisphere, the knee is affected by this progressive disorder in 75 % of the cases, specifically the medial femoral condyle (70 - 80 %). The etiology is uncertain, although genetic defects, micro-trauma, ossification disorders and ischemia have been implicated. Pathogenetically, Osteochondritis dissecans is classified in four stages, whereas in stage one, there is merely a subchondrial edema. Without therapy this could lead to stage 4, with a free osteochondral joint fragment. Treatment is analogous with the stage of the disorder. Whereas conservative treatment may yield full recovery during stage 1, starting in stage 2, invasive treatment should be considered. When the cartilage surface remains intact retrograde procedures are indicated. If the cartilage is injured anterograde therapies, like the chondral or osteochondral transplantation, should be used.

[Imaging in rheumatology. Degenerative diseases of the spine]. / Bildgebende Verfahren in der Rheumatologie. Bildgebung bei degenerativen Erkrankungen der Wirbelsäule.

Degeneration of the spine is a common reason for pain in the musculoskeletal system. Radiography is an important tool for diagnosis and differential diagnosis. Cost efficacy and economy of time are advantages in using conventional x-rays. Although narrowing of intervertebral disc spaces, irregular ossification of the vertebral end-plate as well as osteophytes, facet joint osteoarthritis and spondylolisthesis can be observed, early changes in the discs or the subdiscal bone can not be detected by x-rays. Moreover, 3-dimensional imaging is not possible. Computer tomography (CT) and magnetic resonance imaging (MRI) are reliable for identifying disorders of the spine and soft-tissue. Differentiation between inflammation, trauma and tumor is possible. There is still a problem with the relationship between the information obtained by x-rays or MRI and clinical symptoms. Therefore, interpretation of radiological examinations assumes a knowledge of clinical symptoms and the different kinds of diseases which are possible.

[Conventional X-rays and conventional tomography in orthopaedics. Current status]. / Konventionelle Röntgenaufnahme und konventionelle Tomografie für die Orthopädie. Aktueller Stellenwert.

Although sonography, computed tomography (CT) and magnetic resonance imaging (MRI) are common tools in radiology, conventional X-rays still have a place in orthopaedic diagnostic investigation. The advantages of radiographic imaging are high local resolution concerning bone, economy of time besides relatively low costs and worldwide experience. The conventional X-ray is indispensable for planning surgical procedures and clinical monitoring. For several pathological processes an X-ray is sufficient for diagnosis and therapy (i.e. degeneration, fracture). Early changes of the bone (i.e. osteonecrosis) cannot be detected by X-ray. CT and MRI have closed the diagnostic gap. Indications for conventional tomography are rare.

[Clinical relevance of multislice CT of the spine after osteosynthesis]. / Postoperative Kontrolle von osteosynthetischen Versorgungen der Wirbelsäule mit der Mehrzeilen-Spiral-CT.

PURPOSE: To examine the clinical relevance of multislice CT (MSCT) scans in postoperative checks of the spine after osteosynthesis. MATERIAL AND METHODS: The results of x-rays (apical lateral) in 30 patients having spinal surgery involving osteosynthesis (5 x metastasis, 20 x fractures, 3 x spondylolisthesis, 2 x scoliosis) were correlated to those of MSCT (140 kV, 200 mAs, collimation 4 x 1 mm, pitch 0.75; VolumeZoom, Siemens, Erlangen, Germany) with multiplanar reconstruction. Two radiologists independently checked the conventional x-ray and multislice CT scans for anatomical positioning, damage of osteosynthetic material, and intraspinal dislocation of bone fragments. RESULTS: By correlating conventional spinal x-rays with MSCT, additional diagnostic information was gained. In 9 of 30 patients MSCT revealed the extraosseal location of a screw tip (x-ray, 5/30), in 8/30 patients a narrowing of the spinal canal by osteosynthetic material was detected in MSCT (x-ray, 4/30), in 2/30 patients osteal fragments were detected in the vertebral canal by MSCT (x-ray, 0/30). In MSCT and in conventional x-ray a fracture of the osteosynthesis was correctly diagnosed in 3 patients. One patient underwent corrective surgery for dislocated osteosynthetic material, which was solely diagnosed with MSCT. CONCLUSION: Due to the high degree of additional diagnostic information MSCT seems to be the method of choice for postoperative spinal surgery involving osteosynthesis.

[Effects of low-frequency pulsed electromagnetic fields on the proliferation of chondrocytes]. / Auswirkungen NF-gepulster elektromagnetischer Felder auf die Proliferation von Chondrozyten.

Chondrocytes isolated from the human cartilage of 5 patients between the ages 23 and 56 were exposed to low frequency pulsed electromagnetic fields (9 mT; 3 Hz) for a daily period of 60 minutes on 5 consecutive days and then every 48 hours for the next 6 days (11 days in total). Cell viability was estimated using trypan blue exclusion and proliferation was estimated by counting the cells in a haemacytometer. Cell morphology was compared for control purposes by directly observing the cells under a light microscope after staining cells in a haematoxylin and eosin solution. The results were statistically analysed and compared to a control sample. Data revealed that exposing cells isolated from human cartilage to pulsed electromagnetic fields (9 mT; 3 Hz) led to a significantly higher number of cells in comparison to the control sample. Among the cells from the 5 patients, growth varied between 1.1 to 3.0 folds compared to the control sample. The difference in cell viability between the exposed cells and the control sample was, however, not significant. Some morphological variations were revealed when the cells were observed under a light microscope. The exposed cells were thinner and longer than the control cells which were large and flat. The exposed cells tended to grow in a more uniform direction while the control cells grew in all directions. These differences in morphology and growth may be related to the higher density of the exposed cells.