[Treatment of epicondylitis - a current review]. / Die Therapie der Epicondylitis - eine aktuelle Übersicht.

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.

Evaluation of aseptic loosening of knee prostheses by quantitative bone scintigraphy.

UNLABELLED: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

[Usefulness of 16S rDNA polymerase-chain-reaction (PCR) in the intraoperative detection of infection in revision of failed arthroplasties]. / Wert der 16S rDNA Polymerase-Ketten-Reaktion (PCR) zur intraoperativen Infektdetektion bei Endoprothesenrevisionseingriffen.

AIM: 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. METHOD: 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. RESULTS: 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. CONCLUSION: 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.

[Infection diagnosis after knee-TEP-implantation]. / Infektdiagnostik nach Knie-TEP-Implantation.

AIM: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

[Stage diagnostics for postinfection revision of hip and knee replacement: value of laboratory parameters and antigranulocyte scintigraphy]. / Stufendiagnostik bei postinfektiöser Hüft- und Knie-TEP-Implantation: Aussagekraft von Laborparametern und Antigranulozytenszintigraphie.

AIM: 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. METHOD: 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. RESULTS: 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. CONCLUSION: 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.

[Patella resurfacing in patients without substantial retropatellar knee pain symptoms?]. / Patellarückflächenersatz bei Patienten ohne wesentliche retropatellare Beschwerdesymptomatik?

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

[Femoral neck fractures in the elderly -- bipolar hemiarthroplasty in total hip replacement]. / Die Schenkelhalsfraktur beim alten Menschen--Bipolare Hemiendoprothese vs. Totalendoprothese.

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 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. 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.

Development of the acetabulum in patients with slipped capital femoral epiphysis: a three-dimensional analysis based on computed tomography.

Orientation and shape of the acetabulum were determined by the use of three-dimensional reconstruction of computed tomography (CT) data sets in 22 patients with a total of 30 slipped capital femoral epiphyses. We developed an interactive three-dimensional software program to measure the anteversion and inclination of the acetabulum without projectional and pelvis-tilting errors. Furthermore, we determined the height, width, depth, volume, and surface of the acetabulum as parameters describing the acetabular shape. Comparison of the affected side with the contralateral unaffected hip showed no significant differences for acetabular orientation and shape. The relationship between the degree of the slip and the acetabular orientation was calculated. No correlation was found. Based on the results of this study, we conclude that the slipping of the capital femoral epiphysis has no influence on acetabular development.

Three-dimensional analysis of the proximal femur in patients with slipped capital femoral epiphysis based on computed tomography.

A three-dimensional (3D) analysis based on computed tomography was performed to study the 3D geometry of the proximal femur in cases of slipped capital femoral epiphysis (SCFE). For this purpose, new interactive software was developed to analyze hip joint geometry using 3D models without pelvis tilting and projected errors. Twenty-two patients, 8 girls and 14 boys, with a total of 30 slipped capital femoral epiphyses, were reviewed. In the affected hips, we observed a reduced femoral anteversion of 7.0 degrees (vs. 12.7 degrees) and a reduced femoral shaft neck angle of 134.2 degrees (vs. 141.0 degrees). In response to these results, we suggest that an SCFE is associated with reduced femoral anteversion and a reduced femoral shaft neck angle.

[Results of one-stage endoprosthesis revision in periprosthetic infection cause by methicillin-resistant Staphylococcus aureus]. / Ergebnisse einzeitiger Endoprothesenwechsel bei periprothetischer Infektion durch einen methicillin-resistenten Staphylococcus aureus (MRSA).

OBJECTIVE: Are the results of one-stage exchange arthroplasties to treat periprosthetic infection caused by methicillin-resistant Staphylococcus aureus (MRSA) comparable to bacteriologically unselected studies of one-stage exchange operations? METHOD: From 1996 to 1997 twenty patients with a periprosthetic infection caused by methicillin-resistant Staphylococcus aureus (MRSA) were treated at the ENDO-Klinik by an one-stage exchange arthroplasty. Mean follow-up of fifteen one-stage exchange total hip replacements and 5 one-stage exchange total knee replacements was 16 months. The patients were examined by means of clinical, laboratory-chemical and radiological tests. In addition, postoperative joint aspiration was performed on 14 patients. RESULTS: In 11 cases (61%) the periprosthetic infection was treated successfully with only one one-stage exchange operation. In cases with persisting infection the period between the first exchange arthroplasty and the repeated clinical manifestation of the infection (second exchange operation) was 2 months on average. 93% of the joint aspirations (n = 14), performed on average 4 weeks postoperatively, correlated with the result of the follow-up tests. CONCLUSION: Periprosthetic infection with MRSA is a problematic infection. Because of the reduced therapeutic possibilities it is associated with a higher rate of recurrence than the unselected group of patients as a whole [6, 11, 16, 17, 19, 20]. The authors recommend one-stage exchange arthroplasty using a combination of vancomycin and ofloxacin as admixture to polymethylmethacrylat (Refobacin Palacos R). This procedure does, however, need further development. Intraoperative use of an antiseptic and systemic administration of rifampicin, as recommended by Zimmerli [23] is a further possibility.

[Migration analysis of cemented Müller polyethylene acetabular cups versus cement-free Zweymüller screw-attached acetabular cups]. / Migrationsanalyse zementierter Müller-Polyethylenpfannen versus zementfreier Zweymüller-Schraubpfannen.

OBJECTIVE: Is the cementless Zweymüller hip cup superior to the cemented Müller cup? METHOD: This article presents a radiographic analysis of 25 cemented Müller acetabular cups versus 22 cementless Zweymüller cups using the Einbildröntgenanalyse (EBRA), a software tool for radiographic measurement of acetabular cup migration. In addition, we determined the effects of the cup anteversion and inclination, the polyethylene wear, the lateral bone coverage of the acetabular cup, the position of the center of rotation, and individual factors on the incidence of cup migration. RESULTS: The incidence of cup migration was 64% in the cementless group and 48% in the cemented group after a mean follow-up of 6 years. The average migration rate was 0.33 mm/a for cementless Zweymüller cups and 0.38 mm/a for cemented Müller cups. Cup anteversion and inclination showed no effect on the incidence of cup migration. The combination metal-polyethylene (0.17 mm per year) demonstrated a significantly higher wear rate in comparison to the ceramic-polyethylene combination (0.11 mm per year). Incompletely lateral covered cups demonstrated a significantly higher incidence of cup migration. Cranial or medial deviations of the center of rotation up to 5 mm are tolerable, in contrast to caudal or lateral deviations that lead to a significantly higher incidence of cup migration. CONCLUSION: The superiority of the cementless Zweymüller cup was not observed. We recommend a complete lateral bone coverage of the hip cup. Cranial and medial deviations of the center of rotation up to 5 mm are tolerable. In the present study the polyethylene wear of the ceramic-polyethylene combination was significantly less as compared with the metal-polyethylene combination.

Anatomical analysis and preoperative planning of correctional osteotomies: slipped capital femoral epiphysis (SCFE).

SCFE is defined as the slippage of the femoral head relative to the femoral neck along the proximal femoral growth plate. The femoral head shifts and rotates along the proximal end of the femoral neck, usually posteriorly and interiorly. The pathoanatomical findings are characterised by the changed relationship between the femoral head and femoral metaphysis, and between the femoral head and the acetabulum. A reduced femoral anteversion, a varus deformity of the femur, a shortening of the femoral metaphysis and an anterior metaphyseal prominence are also regularly observed. This may lead to impingement between the femoral metaphysis and the acetabular rim. Potential consequences of this complex 3D deformity are pain, a reduced range of hip motion and an early degenerative joint disease. In moderate and severe cases a redirectional femoral osteotomy is recommended. Different techniques, such as subcapital, base-of-neck, intertrochanteric and subtrochanteric osteotomies, have been described. These correctional osteotomies aim towards a reconstruction of the hip joint geometry, to prevent early arthritic degeneration. Currently, the planning of surgical treatment in these cases is based on measurements on antero-posterior and lateral plain radiographs. The relevant angle for planning of correctional osteotomies is the physis-shaft angle, determined in both plains. These angles describe the degree of slippage, thereby helping the surgeon to indicate and plan a correctional osteotomy. However, plain radiographs are projectional images and therefore carry inaccuracies caused by the overlay of anatomical structures and an incorrect positioning of the patient. 3D reconstructions are more accurate and provide substantial additional information for the surgeon, such as, for example, the anteversion of the acetabulum. We have developed interactive 3D software to measure projected angles, to analyse the geometry of the proximal femur and to determine the orientation of the acetabulum based on 3D reconstructions of CT data-sets. A program was also developed to simulate different techniques of osteotomies and to evaluate the postoperative range of hip motion and the hip-joint geometry. Accurate 3D measurements, additional anatomical information, simulations of different techniques of osteotomies and the evaluation of simulated postoperative results enables the surgeon to determine the best surgical treatment, based on the clinical findings.