[Show abstract][Hide abstract] ABSTRACT: Destruction of articular cartilage is a characteristic feature of osteoarthritis (OA). Collagen hydrolysates are mixtures of collagen peptides and have gained huge public attention as nutriceuticals used for prophylaxis of OA. Here, we evaluated for the first time whether different bovine collagen hydrolysate preparations indeed modulate the metabolism of collagen and proteoglycans from human OA cartilage explants and determined the chemical composition of oligopeptides representing collagen fragments. Using biophysical techniques, like MALDI-TOF-MS, AFM, and NMR, the molecular weight distribution and aggregation behavior of collagen hydrolysates from bovine origin (CH-Alpha®, Peptan™ B 5000, Peptan™ B 2000) were determined. To investigate the metabolism of human femoral OA cartilage, explants were obtained during knee replacement surgery. Collagen synthesis of explants as modulated by 0-10 mg/ml collagen hydrolysates was determined using a novel dual radiolabeling procedure. Proteoglycans, NO, PGE(2), MMP-1, -3, -13, TIMP-1, collagen type II, and cell viability were determined in explant cultures. Groups of data were analyzed using ANOVA and the Friedman test (n = 5-12). The significance was set to p≤0.05. We found that collagen hydrolysates obtained from different sources varied with respect to the width of molecular weight distribution, average molecular weight, and aggregation behavior. None of the collagen hydrolysates tested stimulated the biosynthesis of collagen. Peptan™ B 5000 elevated NO and PGE(2) levels significantly but had no effect on collagen or proteoglycan loss. All collagen hydrolysates tested proved not to be cytotoxic. Together, our data demonstrate for the first time that various collagen hydrolysates differ with respect to their chemical composition of collagen fragments as well as by their pharmacological efficacy on human chondrocytes. Our study underscores the importance that each collagen hydrolysate preparation should first demonstrate its pharmacological potential both in vitro and in vivo before being used for both regenerative medicine and prophylaxis of OA.
PLoS ONE 04/2013; 8(1):e53955. DOI:10.1371/journal.pone.0053955 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Even today there are still some cases of clubfoot that require a more extensive form of treatment. Thus, it is still essential to ascertain the development of the clubfoot after extensive release operations.
70 children presenting 99 cases of primary clubfoot (age 8 months-10 years) were followed up after 4.5 and 9 years following complete subtalar release. Function, clinical and radiological results as well as 3 scores were assessed at both dates.
Function and pain worsened between the two follow-up periods, whereas objective clinical and radiological results remained equivalent. 44-79% were rated good or excellent depending on the scoring system applied.Older children with primary clubfoot had comparable results to children operated on at a younger age; also pre-operated feet achieved similar results.
In our opinion the results justify keeping complete release in mind as an alternative method in cases of severe residual and recurrent clubfoot.
Foot and Ankle Surgery 03/2012; 18(1):55-61. DOI:10.1016/j.fas.2011.03.006
[Show abstract][Hide abstract] ABSTRACT: In this prospective study we compared clinical and radiological results and rehabilitation progress of 64 patients who underwent total hip arthroplasty using the standard lateral approach with 64 patients operated with a minimal-invasive (MIS) posterior approach. The outcome of our study did not show any significant differences with regard to patient's safety such as complication rate and radiological assessment of the cup position. There was no difference in the duration of surgery, blood loss, hospital stay and postoperative leg length discrepancy. Rehabilitation milestones were achieved earlier by MIS patients and three and six months postoperatively, the Harris Hip Score of the MIS group was significantly higher.
[Show abstract][Hide abstract] ABSTRACT: Lateral epicondylitis or tennis elbow is a common injury, which affects not only people who play tennis but occurs with many different activities. It reflects overuse of the extensor muscles of the forearm. There are some other pathologies which have to be separated from epicondylitis. The choice of different treatments is hard to overlook and there are only a few good clinical trials which support one treatment option by means of evidence based medicine. During the acute phase topical NSAIR, steroid injections, ultrasound and acupuncture are helpful. There is no consensus about the effectiveness of physiotherapy, orthoses, laser, electrotherapy or botulinumtoxininjections. During the chronic phase none of the different treatment modalities is effective according to criterias of evidence based medicine. By now, it has not been proven whether patients profit during that time of physiotherapy, orthoses, extracorporeal shock wave therapy or an operation. Whether orthobiological treatment options may play a role in the future is presently uncertain.
[Show abstract][Hide abstract] ABSTRACT: Tetracyclines were reported to slow down the progression of cartilage damage both in an animal model of osteoarthritis (OA) and in humans. In search for the underlying mechanisms we examined whether tetracyclines possess an inhibitory potential on the activity of aggrecanases and inflammatory mediators and can thus prevent proteoglycan (PG) loss from human articular cartilage. In vitro activity of aggrecanase-1 and -2 was recorded in the presence of 1-100 microM tetracycline, minocycline, or doxycyline. Human knee articular cartilage explants were sorted according to the degree of OA and treated for 10 days with tetracycline derivatives in the presence of interleukin-1 (IL-1beta). Synthesis and loss of PGs, nitric oxide (NO), and prostaglandin E(2) (PGE(2)), as well as the viability were determined. Tetracyclines derivatives dose-dependently inhibited the activities of both aggrecanases in vitro, whereas no inhibitory effect of tetracyclines on any proteoglycanolytic activities within IL-1beta-treated human cartilage explants were found. Tetracyclines can significantly modulate NO and PGE(2) levels, but have no effect on PG synthesis and loss within the same human cartilage explant cultures. Altogether, our data show that tetracyclines have no inhibitory potential on any proteoglycanolytic activities within mild or moderately affected human OA cartilage at therapeutic achievable plasma levels.
Journal of Orthopaedic Research 06/2010; 28(6):828-33. DOI:10.1002/jor.21026 · 2.99 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In not infected knee prostheses bone scintigraphy is a possible method to diagnose mechanical loosening, and therefore, to affect treatment regimes in symptomatic patients. However, hitherto studies showed controversial results for the reliability of bone scintigraphy in diagnosing loosened knee prostheses by using asymptomatic control groups. Therefore, the AIM of our study was to optimize the interpretation procedure and to evaluate the accuracy using results from revision surgery as standard.
Retrospectively, we were able to examine the tibial component in 31 cemented prostheses. In this prostheses infection was excluded by histological or bacteriological examination during revision surgery. To quantify bone scintigraphy, we used medial and lateral tibial regions with a reference region from the contralateral femur.
To differentiate between loosened and intact prostheses we found a threshold of 5.0 for the maximum tibia to femur ratio of the both tibial regions and a threshold of 18% for the difference of the ratio of both tibial regions. Using these thresholds, values of 0.9, 1, 0.85, 1, and 0.94 were calculated for sensitivity, specificity, negative predictive value, positive predictive value, and accuracy, respectively. To get a sensitivity of 1, we found a lower threshold of 3.3 for the maximum tibia to femur ratio.
Quantitative bone scintigraphy appears to be a reliable diagnostic tool for aseptic loosening of knee prostheses with thresholds evaluated by revision surgery results being the golden standard.
[Show abstract][Hide abstract] ABSTRACT: In this study, the accuracy of antigranulocyte scintigraphy as a diagnostic means prior to revision in infected total knee replacement was compared to that of preoperative joint aspiration and laboratory parameters. The most efficient combination of all diagnostic methods was calculated and thus a diagnostic algorithm recommended. The value of PCR was compared to commonly used techniques of microbiological culturing.
Preoperative diagnostic means for infection of 50 total knee replacements in 45 patients requiring revision surgery, were retrospectively analyzed. Inclusion criteria were the intraoperative microbiological and histological verification of infection. Sensitivity, specificity, negative and positive prediction value of C-reactive protein (CRP) and leukocytes, antigranulocyte scintigraphy with (99m)Tc-labeled antibodies, and preoperative joint aspiration were calculated. Furthermore, the accuracy of the different techniques of culturing was compared to that of the polymerase chain reaction (PCR) based on the intraoperative histological findings. Two blinded examiners evaluated specimens taken intraoperatively according to the criteria of Mirra.
We observed a sensitivity of 1.0, a specificity of 0.82, a positive prediction value of 0.83 and a negative prediction value of 1.0 for the antigranulocyte scintigraphy. The sensitivity of preoperative joint aspiration was 0.5, the specificity 1.0, and the positive and negative prediction values were 1.0 and 0.5. Correlated to the intraoperative histological findings the accuracy of PCR and culturing was comparable. The highest accuracy was obtained for blood culture samples.
Compared to preoperative joint aspiration the antigranulocyte scintigraphy proved to be more sensitive in the diagnosis an infected knee replacement while having a high specificity. An advantage of PCR compared to the common microbiological culturing techniques was not observed.
Zeitschrift für Orthopädie 01/2004; 142(3):337-43. DOI:10.1055/s-2004-818772 · 0.86 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Immunoscintigraphy with the use of the antigranulocyte antibody BW 250/183 is a reliable method for detecting infection, especially in septic loosening of hip prostheses, for which purpose quantitative interpretation of the time-activity course is employed. Therefore, we retrospectively studied whether similar results could be achieved in knee prostheses. We verified 28 scintigraphic examinations in 26 patients by histology. Scintigraphy was performed during an early (4-6 h post injection) and a late phase (23-25 h post injection). Infection was diagnosed when activity around the knee prosthesis increased by more than 10% compared with bone marrow. We found a sensitivity and a negative predictive value of 100%, a specificity of 80%, a positive predictive value of 81% and an accuracy of 89%. Specificity and accuracy are lower than in the evaluation of hip prostheses; however, in comparison to other scintigraphic modalities, scintigraphy with the antigranulocyte antibody BW 250/183 is superior in excluding infection and has better specificity and accuracy. Therefore, as in the case of hip prostheses, the described methodology appears to be the scintigraphic modality of choice for knee prostheses.
European journal of nuclear medicine and molecular imaging 12/2003; 30(11):1463-6. DOI:10.1007/s00259-003-1275-1 · 5.38 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In the case of two-stage infect revision arthroplasties of hip and knee joint, of primary resection arthroplasties and before implantation of arthroplasties after septic arthritis the accuracy of preoperative laboratory parameters and antigranulocyte scintigraphy was analysed. Furthermore, we stained the intraoperatively taken joint synovial samples with hematoxylin-eosin and also with antibodies against human neutrophil elastase in order to investigate if immunohistological examination provides further or different information.
In 24 patients with intraoperative verification of infection we calculated sensitivity, specificity, positive and negative predictive values for laboratory tests, antigranulocyte scintigraphy and the most suitable combination of both. The joint synovial samples stained with antibodies against human neutrophil elastase were compared to those stained with hematoxylin-eosin according to the criteria of Mirra.
We observed the best results for the combination of C-reactive protein and antigranulocyte scintigraphy with a sensitivity of 1, a specificity of 0.92, a positive predictive value of 0.75 and a negative predictive value of 1. No additional or different information was observed by the immunohistological stained samples.
Stage diagnostic using C-reactive protein and antigranulocyte scintigraphy provides accurate information to assess the status of infection before hip and knee replacement after infect revision. Additional immunohistological staining besides the routinely taken hematoxylin-eosin staining of joint synovial samples is not recommended.
Zeitschrift für Orthopädie 09/2003; 141(5):547-53. DOI:10.1055/s-2003-42838 · 0.86 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In this study surgical risk and functional outcome of bipolar hemiarthroplasty and total hip replacement in elderly patients with femoral neck fractures were compared.
In a prospective study 54 patients with femoral neck fractures (median age: 80.5 years) were treated by implanting a total hip replacement (group I). Group II comprised 52 patients with 55 femoral neck fractures (median age: 81 years) who underwent bipolar hemiarthroplsty. Pre- and postoperative mobility and social history, perioperative parameters such as duration of surgery, blood loss, and number of transfused blood units as well as postoperative complications and mortality were compared. Function was ascertained by a scoring system.
Duration of surgery, blood loss, and numbers of transfused blood units were significantly lower in group II, and mortality rate was lower. Postoperative mobility and medium-term functional score were comparable, whereas in the longer-term follow-up after 8 years group I had a significantly better functional score.
In elderly patients with femoral neck fracture and high comorbidity, we recommend the implantation of hemiarthroplasty and in healthy, active patients with longer life expectancy the total hip replacement.
Der Unfallchirurg 07/2003; 106(6):467-71. · 0.65 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Introduction. In this study surgical risk and functional outcome of bipolar hemiarthroplasty and total hip replacement in elderly patients with femoral neck fractures were compared.
Methods. In a prospective study 54 patients with femoral neck fractures (median age: 80.5 years) were treated by implanting a total hip replacement (group I). Group II comprised 52 patients with 55 femoral neck fractures (median age:81 years) who underwent bipolar hemiarthroplasty. Pre- and postoperative mobility and social history, perioperative parameters such as duration of surgery, blood loss, and number of transfused blood units as well as postoperative complications and mortality were compared. Function was ascertained by a scoring system.
Results. Duration of surgery, blood loss,and numbers of transfused blood units were significantly lower in group II, and mortality rate was lower. Postoperative mobility and medium-term functional score were comparable, whereas in the longer-term follow-up after 8 years group I had a significantly better functional score.
Conclusion. In elderly patients with femoral neck fracture and high comorbidity,we recommend the implantation of hemiarthroplasty and in healthy, active patients with longer life expectancy the total hip replacement.
Der Unfallchirurg 01/2003; 106(6):467-471. DOI:10.1007/s00113-003-0597-6 · 0.65 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The aim is of this prospective randomised study was to investigate the necessity of resurfacing the patella in combination with total knee arthroplasty in patients without or mild anterior knee pain before undergoing total knee replacement.
Between May 1999 and May 2000 fifty patients were enrolled in a prospective, randomised study. All patients received the same posterior-cruciate-sparing total knee replacement and were randomised to treatment with and without resurfacing of the patella. Inclusion criteria were primary osteoarthritis of the knee, preoperatively no pain when the patella was shifted during clinical examination, a maximal grade III radiological degeneration of the patella according to Sperner et al. and at most a mild anterior knee pain in preoperative interview. Evaluations consisted of the determination of the Knee Society clinical score, the completion of a patient satisfaction questionnaire, and radiographic assessment basing on the Knee Society roentgenographic evaluation and scoring system. All patients were examined preoperatively and 3, 6, and 12 months postoperatively.
In all postoperative examinations patients with patella resurfacing demonstrated a higher overall Knee Society score. At month 6 the difference was statistically significant. The patient satisfaction questionnaire demonstrated no significant difference between both groups. However, regarding to relief of anterior knee pain and improvement of pain in general patients with nonresurfacing were less satisfied at all follow-ups. Furthermore, after 12 months all answers to the patient satisfaction questionnaire of the resurfaced group were better. Patella-associated revisions were performed in two patients without resurfacing. Radiographic analysis demonstrated no loosening, fracture, subluxation or dislocation.
The presented study demonstrated after one year follow-up a better functional result, a higher degree of contentment and fewer complications after total knee replacement with patella resurfacing in patients without or mild preoperative anterior knee pain.
Zeitschrift für Orthopädie 01/2003; 141(5):557-62. DOI:10.1055/s-2003-42850 · 0.86 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In this study the accuracy of the 16S DNA polymerase chain reaction (PCR) in revision arthroplasties was compared to that of conventional bacterial culture when correlated to intraoperative histological findings. Furthermore, the influence of antibiotic treatment and different ways of collecting samples was evaluated.
In a prospective study we collected samples of tissues, aspiration fluids and swabs during revision arthroplasty surgery and examined them with PCR as well as conventional bacterial culturing methods. Also, we correlated these two methods with the histological findings of intraoperative tissue samples. Two independent examiners evaluated the samples according to the criteria of Mirra et al. Sensitivity, specificity, positive and negative prediction value and the accuracy were calculated for the molecular biological and culture methods. Three groups were defined to evaluate the influence of accompanying antibiotic treatment and the way of collecting the microbiological samples.
Nine periprosthetic infections could be detected by PCR as well as by conventional bacterial culturing. Correlated with the 25 positive histological findings this resulted in a sensitivity of 0.36, a specificity of 1.0, a negative prediction value of 0.61, a positive prediction value of 1.0 and an accuracy of 0.68 for both methods. Swabs compared to aspiration fluids and tissues samples showed the highest sensitivity with both methods. No higher sensitivity of PCR compared to conventional bacterial culturing could be observed in patients with accompanying antibiotic treatment.
Although PCR is more rapidly available for the diagnosis of periprosthetic infection, a definite advantage of this more expensive method could not be demonstrated in view of the same low sensitivity of PCR and conventional bacterial culturing.
Zeitschrift für Orthopädie 142(5):571-6. · 0.86 Impact Factor