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D Pape

Publications and source records attributed to D Pape.

At least 19 recordsLinked to original sources
PubMed2006

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.

Adult↗
PubMed2006

Effects of phlebotomy therapy on cytochrome P450 2e1 activity and oxidative stress markers in dysmetabolic iron overload syndrome: a randomized trial.

AIM: To assess the effects of iron removal on cytochrome P450 2E1 activity and oxidative stress in dysmetabolic iron overload syndrome. METHODS: Forty-eight patients were randomized to phlebotomy therapy consisting of removal of 300-500 mL of blood every 14 days until serum ferritin levels dropped under 100 microg/L or to follow-up without phlebotomy therapy. Cytochrome P450 2E1 activity was measured at baseline and at the end of treatment by using the 6-hydroxychlorzoxazone/chlorzoxazone blood metabolic ratio, 2 h after the intake of 500 mg of chlorzoxazone. RESULTS: In the treatment group, a mean of 3.9 +/- 1.3 L of blood was removed and serum ferritin levels dropped from 715 +/- 397 to 74 +/- 34 microg/L. Variation of cytochrome P450 2E1 activity was not significantly different between the 2 groups (0.07 +/- 0.26 vs. 0.03 +/- 0.19, P = 0.36). In the treatment group, low-density lipoprotein cholesterol and vitamin E were lowered after treatment compared with control group (-0.15 +/- 0.51 vs. 0.24 +/- 0.58, P = 0.002 and -1.3 +/- 4.4 vs. 2.3 +/- 5.2, P = 0.03, respectively). Inversely, vitamin C was increased (0.5 +/- 3.5 vs. -1.8 +/- 3.9, P = 0.03). CONCLUSIONS: In dysmetabolic iron overload syndrome, reduction of iron stores does not significantly influence cytochrome P450 2E1 activity but is associated with a significant decrease of low-density lipoprotein cholesterol, suggesting that venesection therapy may be a suitable option in these patients.

Ascorbic Acid↗
PubMed2004

An expression profile of human pancreatic islet mRNAs by Serial Analysis of Gene Expression (SAGE).

AIMS/HYPOTHESIS: The Human Genome Project seeks to identify all genes with the ultimate goal of evaluation of relative expression levels in physiology and in disease states. The purpose of the current study was the identification of the most abundant transcripts in human pancreatic islets and their relative expression levels using Serial Analysis of Gene Expression. METHODS: By cutting cDNAs into small uniform fragments (tags) and concatemerizing them into larger clones, the identity and relative abundance of genes can be estimated for a cDNA library. Approximately 49,000 SAGE tags were obtained from three human libraries: (i) ficoll gradient-purified islets (ii) islets further individually isolated by hand-picking, and (iii) pancreatic exocrine tissue. RESULTS: The relative abundance of each of the genes identified was approximated by the frequency of the tags. Gene ontology functions showed that all three libraries contained transcripts mostly encoding secreted factors. Comparison of the two islet libraries showed various degrees of contamination from the surrounding exocrine tissue (11 vs 25%). After removal of exocrine transcripts, the relative abundance of 2180 islet transcripts was determined. In addition to the most common genes (e.g. insulin, transthyretin, glucagon), a number of other abundant genes with ill-defined functions such as proSAAS or secretagogin, were also observed. CONCLUSION/INTERPRETATION: This information could serve as a resource for gene discovery, for comparison of transcript abundance between tissues, and for monitoring gene expression in the study of beta-cell dysfunction of diabetes. Since the chromosomal location of the identified genes is known, this SAGE expression data can be used in setting priorities for candidate genes that map to linkage peaks in families affected with diabetes.

Chromosomes, Human, Pair 1↗
PubMed2004

[Imaging and preoperative planning of osteotomy of tibial head osteotomy].

Valgus-producing osteotomy of the proximal tibia is a well-established treatment for medial femorotibial osteoarthritis in the varus knee. The ideal patient is active, under 55 years of age, has a stable varus deformity of less than 10 degrees, a good bone stock, and an osteoarthritis stage that is restricted to the medial compartment of the knee. Coventry reported a failure rate in proximal tibial osteotomy to be significantly higher when the postoperative alignment was less than 8 degrees of anatomical valgus. Hernigou noted better clinical long-term results in cases with a precise correction of malalignment. There are different preoperative planning methods varying between simple estimates of correction angles and specific radiographic planning tools. The reproducibility of operative outcome with regard to a predictable anatomic alignment and functional recovery must have high priority. This chapter deals with different preoperative planning methods to improve the reliability of surgical results after tibial osteotomy.

Adult↗
PubMed2004

[Stability, bone healing and loss of correction after valgus realignment of the tibial head. A roentgen stereometry analysis].

In high tibial closing-wedge osteotomies (HTO), closure of an osteotomy gap after resection of a bony wedge can be associated with a fissure of the medial cortex of the tibial head (MCT). The effect of a broken MCT on the recurrence of varus deformity is disputed. In this study, serial roentgen stereometric analysis (RSA) was used to determine the fixation stability of a rigid internal "L" plate after HTO. Full weight lower limb radiographs were used to determine the sagittal alignment in patients with varying degrees of varus malalignment and correction over time. Forty-two patients with varus gonarthrosis stage I-III (Ahlback) were treated with HTO and internal fixation with an L-shaped rigid plate. Patients were followed by serial RSA, conventional radiographs, and clinical evaluation (Hospital of Special Surgery score) over a 12-month period. In 19 of 42 successive patients, an average wedge size of 6.9 degrees was resected leaving the MCT intact (group 1). In 23 of 42 of patients, the MCT was unintentionally fissured during surgery when an average 10.3 degrees -wedge was resected (group 2). In group 2, RSA revealed a fivefold increase in lateral displacement of the distal tibial segment within 3 weeks after HTO. Twelve weeks after HTO, translations between tibial segments were below the accuracy of the RSA setup in the majority of patients. Group 1 patients demonstrated a higher initial fixation stability, less occurrence of varus deformity, and a higher HSS score compared to patients with larger wedge sizes and frequent fracture of the MCT (group 2). Before bone healing is achieved, the integrity of the MCT plays a crucial role for the clinical and radiological outcome after HTO.

Adult↗
PubMed2004

Gender-specific differences in school sports injuries.

OBJECTIVE: About 5 % of the pupils suffer from an injury in school sports every year. In addition to the kind of injury, the localization and the type of sport, the corresponding reasons for the injuries should be investigated to provide insights for physical education. METHODS: In a prospective study 213 accident cases with 234 injuries during physical education classes were examined. At primary presentation in our clinic, an empirical questionnaire was used to document the grade of class, the exact time point of the injury, the question of guilt, out-of-school sports activity as well as the mechanisms of injuries and the type of sport. Clinicians who worked in our out-patient clinic completed the questionnaire after physical examination documenting diagnosis, therapy and the duration of restriction of sports practice. All patients were followed until returning to physical education at school. The data were statistically analyzed using the chi (2)-test to examine gender-specific differences. RESULTS: Gender-specific differences were seen in the type (p = 0.018) and mechanisms (p = 0.028) of injuries. The most common injuries were sprains (female pupils 36.8 % male pupils 24.5 %], contusions (female pupils 27.4 % male pupils 27.9 %) and fractures (female pupils 14.7 % male pupils 18.6 %). Frequent mechanisms of injuries were errors in basic motion training like running, jumping and catching (female pupils 35.8 % male pupils 28.8 %). No gender-specific differences could be shown for the localization of injuries or for the type of sport. The upper extremity with 55 % was more frequently involved than the lower extremity with 37 %. Playing soccer (21.2 %) and basketball (19.8 %) were the most frequent reasons for sports injuries. The highest prevalence of school sports injuries occurred at the onset of and during puberty. CONCLUSION: For the girls it is necessary to improve the basic motor skills, while the boys need to learn considerate behavior and how to read the game. Basic skill levels in ball games must be improved before practice in competition form is initiated.

Adolescent↗
PubMed2002

Femoral anatomy, computed tomography and computer-aided design of prosthetic implants.

Precise digital data of the internal femoral anatomy are necessary to develop new prosthetic implants with computer-aided design (CAD) techniques. Thirty human cadaveric femurs of central European origin were analysed by high precision computed tomography (CT) using thin slice and high resolution imaging. The CT data were image processed with thresholding to obtain a reconstruction of the cortical bone geometry. The CT threshold for cortical bone was optimized by comparison with saw cuts of macerated femurs. For each specimen a three-dimensional (3D) model of the cortical femur was calculated by the CAD system based on the processed CT data. Virtual 3D models of the 30 femurs were used to adjust a hypothetical stem to the proximal femur anatomy by repeated virtual implantations. The CAD system allowed for evaluation of anatomical parameters after hip reconstruction, amount of bone removal, and cortical bone contact. The fit and fill of the stem could be tested before clinical application and implant-related problems could be corrected.

Aged↗
PubMed2001

[Approach to open treatment of osteochondral lesions of the talus].

Arthroscopic techniques still represent the treatment of choice in osteochondral lesions of the talus (OLT). Open techniques may be used as an alternative or may be complementary to arthroscopic treatments. They are especially indicated in cases of large osteochondral lesions, difficult localisations and in cases of recurrent interventions. In addition to the type of treatment for the lesion itself, the choice of an ideal surgical approach is of paramount importance. Indications, operative technique, possible complications and rehabilitation are described in detail for each approach. Anterolateral, anteromedial, posterolateral and posteromedial soft-tissue approaches as well as medial and lateral malleolar osteotomies are discussed. If a distraction is not desired with arthroscopy, posteromedial and posterolateral soft-tissue approaches offer a good alternative for the treatment of posterior OLT. Osteotomy of the (medial) malleolus offers good visualisation of the medial talar dome. With the introduction of new techniques of osteochondral transplantations, the use of this approach is becoming more popular. However, it is an invasive technique and the risk of secondary osteoarthritis after malleolar osteotomy still needs to be determined.

Ankle Injuries↗
PubMed2001

[Biomechanical properties of interference screw implantation in replacement of the anterior cruciate ligament with patellar and hamstring transplants. An experimental study using roentgen stereometry analysis (RSA)].

This experimental roentgen stereometric analysis (RSA) study was performed to measure micromotions between the graft and tunnel under submaximal load in anterior cruciate ligament (ACL) reconstruction. The aim was to evaluate the maximum load at failure, linear stiffness, and slippage of bone-patellar-tendon-bone (BPTB) grafts fixed with interference screws compared to quadrupled hamstring grafts fixed with interference screws. We used 15 porcine tibia specimens for the study. In the BPTB group, the 10 x 25-mm bone plugs were fixed in a tunnel with 10 mm in diameter using a 7 x 25-mm titanium interference screw (n = 5) or a biodegradable screw (n = 5). The five hamstring transplants were folded to a four-stranded graft and armed with a baseball stitch suture. The sutured side was fixed with a 7 x 25-mm biodegradable polylactide screw in an 8-mm tunnel. The tibial bones, tendon grafts, and interference screws were marked with tantalum beads. The grafts were mounted to a custom made load frame and loaded parallel to the axis under RSA control increasing the force in steps of 50 N. Micromotions between bone plug, screw, and tibia were measured with RSA. Accuracy of RSA for the in vitro study was evaluated as 0.05 mm. Hamstring grafts failed at significantly lower maximum loads (492 +/- 30 N) than BPTB grafts (658 +/- 98 N). Linear stiffness of the hamstring graft fixations was eight times lower compared to the BPTB grafts (403 +/- 141 N/mm vs 3500 +/- 1300 N/mm). There was no significant difference between the biodegradable and titanium screws in the BPTB group. Slippage of the graft started at 82 +/- 35 N load in the hamstring group and at 428 +/- 135 N in the BPTB group. Slippage of the graft at 75% of the maximum pull-out strength was measured as 0.36 +/- 0.25 mm in the BPTB and 2.58 +/- 1.08 mm in the hamstring group. The interference screw fixation of a quadrupled hamstring graft showed a lower linear stiffness and an earlier slippage compared to a patellar tendon bone plug. Slippage of the hamstring grafts at submaximal loads may result in fixation failure during rehabilitation.

Animals↗
PubMed2001

The internal calcar septum (femoral thigh spur) in computed tomography and conventional radiography.

OBJECTIVE: The femoral "thigh spur", a cortical septum in the region of the lesser trochanter of the human femur, was first described and named by the German anatomist Merkel in 1874, but it was never examined in detail. To evaluate the frequency and the shape of this structure, a combined anatomical and radiological study was performed using saw-cuts from specimens, high-resolution CT and conventional radiography. DESIGN: Thirty human cadaveric femora of central European origin were analyzed by high-precision computed tomography (CT) using thin slices and high-resolution imaging. The CT data were image processed with thresholding to obtain a reconstruction of high-density bone formations and for three-dimensional imaging. Additionally three macerated femur specimens were cut exactly corresponding to the CT slices. The computed images were validated with the anatomical saw-cuts. RESULTS: A dense trabecular ridge protruding endosteally from the posteromedial cortex was found in all femora. This cortical septum reaching from the femoral neck to the distal part of the lesser trochanter separated the femoral cavity from the cancellous bone inside the lesser trochanter. On conventional radiography the femoral thigh spur could be visualized best in the frog-lateral view of the hip. CONCLUSION: The internal calcar septum is a constant cortical structure. It should be recognized when radiographs or CT images of the proximal femur are interpreted. It could be of importance for metaphyseal fitting of an endoprosthetic stem.

Aged↗
PubMed2001

Blood loss in anterior cruciate ligament (ACL) reconstruction with and without intercondylar notchplasty: does it affect the clinical outcome?

Blood loss is associated with any surgical procedure and should be reduced wherever possible. It was our impression that notchplasty adds to the amount of postoperative bleeding after anterior cruciate ligament (ACL) reconstruction. With posterior placement of the tibial tunnel, notchplasty is optional in many cases. This study aimed to quantify blood loss with and without notchplasty after arthroscopically assisted ACL reconstruction using bone-patellar tendon-bone autografts. We performed a prospective clinical study of 58 patients, who had undergone arthroscopically assisted autogenous patellar tendon ACL reconstruction. In group I, a notchplasty was necessary according to the local anatomical criteria (intraoperative impingement test). In group II, ACL replacement could be performed without notchplasty. Single and total day drainage volume, serum and suction drain hemoglobin (Hb) and hematocrit (Hct) levels were monitored. One year after surgery, the patients were reviewed to assess the outcome according to the IKDC and Lysholm scores and the KT-1000 arthrometer. The total drainage volume was 448 ml (range 150-550 ml) in group I and 299 ml (range 50-420 ml) in group II (p < 0.001). The serum hematocrit (Hct) decrease was 9.7% in group I and 7.4% in group II (p < 0.001). At 12 months after surgery, the IKDC and Lysholm score evaluations and the KT-1000 arthrometer measurements revealed no clinical differences between the notchplasty and non-notchplasty groups. Despite a 30% increase in blood loss, notchplasty has been shown to be a useful procedure to prevent graft impingement without negative side-effects.

Adult↗
PubMed2001

[Controlled dynamic weight training in patients with neuromuscular disorders].

The question posed was whether individually adapted, controlled dynamic weight training, in accordance with training principles and methods from sports science, applied for a limited time, can lead to an improvement in the stimulation and release of muscular strength in patients with neuromuscular disorders. The muscles of the pelvic girdle and the lower extremity of 10 patients (5 with dystrophic muscle disease and 5 with neurogenic muscular atrophy) were exercised provisionally for a period of 6 weeks on various weight training machines. The training routine was 3 sessions (TS) per week at an intensity range of 40-60% of the respective best performance for the exercise (One Repetition Maximum; ORM), at 8-12 repetitions/set and 2-4 sets/exercise. Body weight and ORM were determined before, during and after the training period (TP), the different load criteria/TS were documented. It was possible to train the patients in accordance with principles of training known from sports science. Over the entire TP it was possible to increase the load criteria significantly (p < 0.01). The ORM had increased considerably in all exercises after the TP (p < 0.01). The changes in strength lay between 11 and 95%. Correlation analyses demonstrated that the percentage changes in strength correlated significantly (p < 0.01) and positively (r = 0.87) with the training load in terms of quality. No significant changes in development of strength could be ascertained between the two groups of patients (dystrophic versus atrophic). The individually adjusted, controlled dynamic weight training described above, leads to an increase in the stimulation and release of strength and can be conducted according to principles of training science. Applied in clinical rehabilitation, it represents a supplementary form of therapy in the symptomatic treatment of neuromuscular disorders.

Adult↗
PubMed2001

Increased sensitivity of vascular smooth muscle to nitric oxide in dilated cardiomyopathy of Syrian hamsters (Bio TO-2 strain).

We assessed the evolution with time of the responsiveness of three vascular beds in dilated cardiomyopathic hamsters of the Bio TO-2 strain. Eight cardiomyopathic hamsters and 8 control hamsters were investigated at 180 and 300 days of age. Thoracic aorta and mesenteric and renal artery rings were studied in isolated organ baths. Cumulative concentration-response relations to phenylephrine, acetylcholine, sodium nitroprusside, and angiotensin II were established for each ring. Maximum effect (Emax) and concentration inducing 50% of Emax (EC50) were determined from each concentration-response curve and pD2 was calculated as -log(EC50). Compared with control hamsters, in cardiomyopathic hamsters, Emax of phenylephrine was not modified in aorta, whereas it was significantly lower in mesenteric (-6% and -33% at 180 and 300 days, respectively) and renal (-17% and -24%) arteries. Emax of acetylcholine was significantly higher in aorta (+57% and +30%), mesenteric (+42% and +34%), and renal (+168% and +70%) arteries. Emax of sodium nitroprusside was significantly higher in aorta (+26% and +16%) and tended to be higher in mesenteric (+25% and +23%) and renal (+27% and +10%) arteries. Emax of angiotensin II was not modified in aorta and tended to be lower in mesenteric artery at 300 days. The pD2 of phenylephrine was significantly increased in aorta and the pD2 of sodium nitroprusside was significantly increased in aorta and renal artery. In conclusion, in dilated cardiomyopathic hamsters, endothelium-dependent and -independent vasodilations are enhanced early, demonstrating increased sensitivity of vascular smooth muscle to nitric oxide. This abnormality may be involved in the decreased responsiveness to phenylephrine and angiotensin II.

Angiotensin II↗
PubMed2001

Hemodynamic and histomorphometric characteristics of dilated cardiomyopathy of Syrian hamsters (Bio TO-2 strain).

The natural history of the disease of the dilated strain Bio TO-2 of cardiomyopathic hamsters (CMH) is not totally characterized. We investigated its hemodynamic and histomorphometric characteristics at 140, 180, 220, 260, and 300 days of age. Forty CMH and 40 controls were investigated (8 at each stage). Mean arterial pressure (MAP, carotid artery catheter) and cardiac output and femoral blood flow (CO, FBF, transit time method) were measured in anesthetized animals. Systemic (SVR) and femoral (FVR) vascular resistances were calculated. Atria, left and right ventricles (LV, RV), lungs, and liver were weighed. LV cavity area, LV and RV wall thicknesses and collagen densities were determined (computer-assisted image analyzer). Pulmonary and hepatic congestion were assessed (arbitrary scales). Compared with controls, MAP, CO and FBF were significantly lower in CMH throughout the study (on average: -22%, -34%, -33%, respectively), FVR was significantly increased (+15%), but SVR was not significantly modified. Concerning histomorphometric characteristics, differences between groups significantly increased with age for most variables: at 300 days, atria (+292%), RV (+13%), lungs (+44%), and liver (+23%) weights, LV cavity area (+130%), LV (+364%) and RV (+181%) collagen densities were significantly increased in CMH vs controls, whereas LV (-40%) and RV (-23%) wall thicknesses were significantly decreased. At 260 and 300 days, CMH showed significant pulmonary congestion without hepatic alteration. Bio TO-2 CMH progressively develop an alteration of cardiac function leading to decreased MAP and musculo-cutaneous blood flow associated with cardiac remodeling including atria hypertrophy and LV dilation, wall thinning and a rise in collagen density.

Age Factors↗
PubMed2000

Primary lumbosacral stability after open posterior and endoscopic anterior fusion with interbody implants: a roentgen stereophotogrammetric analysis.

STUDY DESIGN: After posterior stabilization of the spondylolytic lumbosacral level, mobility of the fused vertebrae could be studied before and after an additional anterior endoscopic interbody fusion using roentgen stereophotogrammetric analysis. OBJECTIVE: To determine the in vivo primary lumbosacral stability of additional anterior interbody fusion after transpedicular screw fixation. SUMMARY OF BACKGROUND DATA: In vitro studies indicate a significant decrease in segmental motion after pedicle screw fixation and additional anterior fusion. Roentgen stereophotogrammetric studies demonstrate the adequacy of transpedicular lumbar instrumentation in posterolateral fusions. There are no studies examining the effect of additional anterior interbody fusion after posterior instrumentation in vivo. METHODS: In this study, 15 patients with low-grade spondylolisthesis at L5-S1 underwent a two-stage open posterior and endoscopic anterior lumbar fusion using carbon fiber (Brantigan I/F) cages. At surgery, tantalum markers were implanted into the fifth lumbar (L5) and the first sacral (S1) vertebra. All the patients were examined by roentgen stereophotogrammetric analysis after the first and second surgical procedures. RESULTS: After implantation of the posterior pedicle system only, the mean intervertebral mobility determined by roentgen stereophotogrammetric analysis was 0.23 mm in the transverse (x), 0.54 mm in the vertical (y), and 1.2 mm in the sagittal (z) axes. After additional anterior endoscopic fusion with carbon cages, the remaining translation between the fused segment L5/S1 decreased to 0.17 mm in the x, 0.16 mm in the y, and 0.44 mm in the z axes. CONCLUSION: Anterior endoscopic lumbosacral fusion significantly increases the primary stability of the posterior fusion with a pedicle system in two axes of motion.

Biocompatible Materials↗
PubMed1999

Free radical involvement in endothelium-dependent responses of the rat thoracic aorta in moderate hypoxic conditions.

This study investigates the effects of agents which act on the production or efficacy of free radicals on the hypoxic responses of rat aorta rings. Under moderate hypoxic conditions, the resting tension of the rings was not changed but in rings precontracted with 5-hydroxytryptamine, there was a relaxation followed by a contraction. Removal of the endothelium with saponin suppressed relaxation to acetylcholine and abolished the contractions produced by hypoxia. In rings with a functional endothelium, hypoxic vasoconstriction was strongly inhibited by mannitol and exifone, but was not reduced by N(G)-nitro-L-arginine methyl ester, superoxide dismutase + catalase, or deferoxamine. Hypoxic vasodilatation was only partially inhibited by mannitol. To conclude, hypoxic constriction of the rat thoracic aorta is largely endothelium-dependent and involves free radicals whereas hypoxic dilatation is partially endothelium-dependent and partially involves free radicals. There is also indirect evidence for lack of direct involvement of nitric oxide/endothelium-derived relaxing factor (NO*/EDRF), hydroxyl radical (OH*) and superoxide anion in the hypoxic constriction and relaxation of the rat aorta.

Animals↗