[Pathophysiology of aseptic femoral head necrosis: Pathogenesis and histopathological differential diagnosis]. / Pathophysiologie der aseptischen Hüftkopfnekrose: Pathogenese und histopathologische Differenzialdiagnostik.

BACKGROUND: Aseptic osteonecrosis is characterized by a complete death of the tissue (necrosis), more specifically, an ischemic necrosis of the lamellar bone tissue. The denotation aseptic refers to causal pathogenesis; therefore, it is not a matter of an infectious, septic-induced bone necrosis as in the case of acute infectious osteomyelitis. Formal pathogenesis leads to either (1) a hypoperfusion of the lamellar bone in the sense of an ischemic necrosis or (2) to directly induced damage of osteocytes and osteoblasts, which causes aseptic osteonecrosis. CAUSE: The causes of hypoperfusion/ischemia are manifold and entail vascular malformations, coagulopathies, haemoglobinopathies, thrombotic embolisms, myeloproliferative illnesses, air embolisms, decompression-caused illnesses, macro as well as micro traumata and, finally, vasculitis with necrosis, which complete the vascular-induced spectrum. Direct toxic damage to the osteocytes and osteoblasts is primarily caused by alcohol abuse, medical drug therapies (i. e. chemotherapeutic substances or cortisone) and disorders of the lipid embolism. Contemporary molecular and cellular models of pathogenesis assume a so-called dysbalance of the catabolic and anabolic osseous metabolism in osteocytes and osteoblasts. The RANKL-RANK system, the ROS system and PPAR-gamma signal transduction are involved in the molecular pathogenesis. DIFFERENTIAL DIAGNOSIS: The most relevant histopathologic differential diagnosis entails the complete spectrum of focal osseous changes among which osteonecrosis can occur to a diverse extent: infectious osteomyelitis, chronic immunologic induced osteomyelitis, pseudoarthrosis, infected pseudoarthrosis, bone fractures and malignant metastatic intraosseous diseases and non-metastatic intraosseous malignant diseases.

[Bradytrophic tissue. Its histopathological diagnosis and value in trauma surgical and orthopedic expert opinions]. / Bradytrophe Gewebe. Histopathologische Diagnostik und Stellenwert bei unfallchirurgisch-orthopädischen Gutachten.

Expert opinions on the musculoskeletal system are generally required for statutory or private accident insurance purposes in a variety of legal areas and with varying rules of evidence. Since they are also intended for non-medical personnel, terminology needs to be defined and must be comprehensible by all parties. Bradytrophic tissue is the most frequently evaluated aspect of the musculoskeletal system. In this context, the term"degeneration" which was formerly used has been replaced by the term"tissue structure alteration", which takes matrix changes and cellularity into consideration. Thus the significance of histopathological diagnosis of bradytrophic tissue has been put in a new light. Histopathological diagnosis is carried out on the basis of various staining methods, scores and analyses depending on the diagnostic question.

[Synergistic joint diagnosis]. / Synergistische Gelenkdiagnostik.

Many methods are useful in the diagnosis of diseases of the joints. Noninvasive methods deserve preference; invasive techniques such as arthrography and arthroscopy are second choice, after noninvasive methods have been applied. The synergic combination of the two last-named methods has proved successful. Arthrography, performed before arthroscopy in the operation theatre, supplements arthroscopy findings and extends the diagnostic value of the arthroscopic findings, in a similar manner as the combination of computed tomography and arthrography.

[Resection of the coracoacromial ligament. A simple surgical procedure for decompression of the subacromial space]. / Die Resektion des Ligamentum coracoacromiale. Ein einfaches operatives Verfahren zur Dekompression des subakromialen Raumes.

Resection of the coracoacromial ligament is a simple method for decompression of the subacromial space. The operation can be performed under arthroscopic control or by means of a small incision above the ligament. 61 patients were operated on by this method during the period between July 1987 and August 1988. 37 patients were questioned regarding the results. In 40% of these there was an alleviation of pain, 48% had an improved motility and 67% would again agree to the operation that appeared indicated (in the patients referred for surgery) both in the impingement syndrome and in antiquated ruptures of the rotator cuffs.

[Acute, traumatic versus chronic cartilage lesions as terms of a medical expert's opinion]. / Akuter, traumatischer versus chronischer Knorpelschaden unter gutachterlichen Gesichtspunkten.

AIM: Have chondral lesions been found in the course of an articular injury? Are these lesions of traumatic or degenerative origin? Is it possible to differentiate traumatic from pre-existing pathology with the help of history, clinical findings and imaging features? The answers to these questions are of paramount importance in the setting of legal expert assessment. METHOD: The diagnosis of an acute traumatic chondral injury is based on arthroscopic and/or MRI findings. MRI is the diagnostic method of choice in a suspected isolated chondral injury. RESULTS: The method yields high accuracy in detecting chondral and osteochondral lesions. The MRI finding of a concomitant subchondral bone contusion ("bone bruise") adjacent to a cartilage lesion helps in the diagnosis of acute chondral lesions. Traumatic bone marrow alterations regress in most cases over the course of 6 months. For this reason the initial MRI should be performed within 1 to 6 weeks after trauma. A follow-up study should be undertaken not prior to 3 months after injury. Osteoarthritic cartilage lesions show a distinct regional pattern on MRI usually affecting the weight-bearing regions. In advanced stages, regularly concomitant osseous reactions such as osteophytes, subchondral sclerosis and bone attrition are observed. Subchondral bone marrow lesions in osteoarthritis show a tendency to progress. CONCLUSION: The direct inspection and probing of the joint during arthroscopy allows for a detailed assessment of the chondral surface and the diagnosis of possible cartilage softening. An arthroscopic differentiation between acute traumatic chondral lesions and chronic cartilage alterations is possible in most cases within the first 6 to 12 weeks after injury.

[The MacIntosh extra-articular knee stabilisation procedure -- an alternative after failed ACL reconstruction?]. / Die extraartikuläre Kniestabilisierung nach MacIntosh -- eine Alternative bei fehlgeschlagenem vorderen Kreuzbandersatz?

Chronic knee instability after loss of the ACL and failed ACL reconstruction is a great problem for the patient and a complex treatment challenge. Minimizing the feeling of instability is the most important issue for the patient. In case of lack of autologous material for reconstruction and lesions of the knee joint because of performed intra-articular procedures, extra-articular techniques are an alternative. In the modified MacIntosh procedure, we tie a strip of iliotibial tractus around the LCL and attach it to the ventrolateral tibial head by screw. Postoperatively, we begin physiotherapy under full weight bearing. Range of motion is limited to 0/0/90 degrees for six weeks. Between 1996 and 2000, nine patients who underwent surgery using the modified Macintosh technique, were evaluated prospectively. The mean follow-up was 11.4 months (6-36 months). We evaluated changes concerning pivot-shift and Lachman-test and documented Lysholm- and Tegner-activity-score pre- and postoperatively. We also registered sporting ability. The pivot shift remained positive, while the anterior drawer, documented by Lachman-test, could be reduced surgically. Lysholm- and Tegner-scores improved significantly. Preoperatively, the mean Tegner-score was 1.44 (0-3), mean Lysholm-score 55.55 points (14-88), respectively. At follow-up examination, scores had improved to 3.55 (3-4) and 82.44 points (69-95), respectively, resulting in a p-value of .007 for the Tegner-, and p = 0.008 for the Lysholm-score. Our surgical treatment could reduce the subjective feeling of instability in all cases. All patients could participate in sports activities at time of follow-up. Our results show, that extra-articular surgical procedures are adequate alternative methods of treatment in cases of persistent knee instability after recurrent failure of ACL reconstruction. The modified MacIntosh procedure described in this study shows encouraging results at medium-term follow-up. The technique is easy to perform and less traumatising for the knee joint.

[Arthroscopy of the elbow joint--indications and results]. / Die Arthroskopie des Ellenbogengelenkes--Indikation und Ergebnisse.

If clinical examination and radiological diagnosis fail to identify undiagnosed complaints in the elbow joint, arthroscopy is indicated. When it is clearly indicated, and when performed by a practised examiner, arthroscopy can make a very useful contribution to the diagnosis of elbow complaints.

[Lesions of the wrist disc. Pathology, diagnosis and treatment]. / Die Läsionen des Handgelenkdiskus. Pathologie, Diagnostik und Therapie.

Lesions of the TFCC are currently a diagnostic and therapeutic challenge. Disc-injuries are often not identified and, therefore, acute ruptures are unfortunately not always immediately repaired. Moreover, therapeutic measures are still sparse and informative trial results are lacking. An anatomical, pathological, diagnostic and therapeutic comparison with the meniscus of the knee is possible.

[Combined endoscopic-radiologic examination of the knee joint]. / Die kombinierte endoskopisch-radiologische Untersuchung des Kniegelenkes.

As a back-up examination to arthroscopy of the knee joint fluoroscopy with production of x-ray films may be performed during CO2 filling of the joint. The carbon dioxide serves as a contrast medium. The method enables some of the gaps left by arthroscopy to be filled. Baker cysts and ruptures of the joint capsule can be demonstrated radiologically. At the 2nd Nuremberg Surgical Clinic 60 patients underwent examination by this method in 1980 and the first half of 1981. In 18 patients pathologic changes were found -- 12 Baker cysts and six ruptures of the knee-joint capsule. The findings were confirmed at surgery. The method was not used in cases of extensive destruction of the knee-joint capsule which had already been established clinically.

[Endoscopic examination of the elbow joint from the dorsoradial approach]. / Die endoskopische Untersuchung des Ellenbogengelenkes vom dorso-radialen Zugang.

At the Second Surgical Clinic in Nürnberg endoscopy of the elbow joint was employed as an aid to diagnosing complaints in 25 elbow joints. The examinations were carried out under anesthetic with dorsoradial approach. The joints were exposed with CO2 gas. There were no complications. Endoscopic examination of the elbow proved helpful both for preoperative diagnosis as well as for the prognosis following elbow-joint surgery.

Arthroscopy and arthrography. A combined procedure.

Arthrography and arthroscopy are invasive diagnostic procedures performed on all main joints of the human body. Both procedures are effective, with differing methods of visualizing intra-articular structures. Whereas the arthrogram reproduces a black-and-white, two-dimensional picture of a spatial structure (an indirect procedure), arthroscopy provides a colored picture facilitating a three-dimensional assessment of the joint cavity, palpation, and the arthroscopic operation. However, both procedures have their weaknesses. False-positive and false-negative results may occur in arthrographic techniques, whereas in arthroscopy, the inability to visualize particular joint regions resulting from the anatomical features of the joints is known. Arthroscopy and arthrography are complementary procedures in joint diagnosis. The present paper is based on experience gathered in 5188 arthroscopies of the six large human joints. Prior to all hand and hip arthroscopies, arthrographic examinations were performed. They provided essential information in 30% of all ankle-joint arthroscopies and in 10% of all knee arthroscopies, but in only a few elbow and shoulder arthroscopies.

[Acute arthroscopy in clinically stable knees with hemarthrosis]. / Die Akut-Arthroskopie bei Klinisch stabilem Knie mit Hämarthros.

From 2006 arthroscopies of the knee, carried out between 1978 and 1983, 196 cases (9.8%) presented with traumatic haemarthroses and clinically stable capsular ligaments. A comparison was made between the standard clinical examination including routine X-ray and arthroscopy carried out under anaesthesia. Arthroscopy, as a diagnostic procedure, was found to be clearly superior with the same minimal complication rate. The standard clinical examination was inferior and inadequate particularly in cases with isolated torn anterior cruciate ligaments, in chondral injuries, and luxation of the patella. Thus, in a recent trauma with haemarthrosis and a clinically stable ligament apparatus, acute arthroscopy is the investigational method of choice, preferably carried out under anaesthesia.

[Therapy and results of fresh lateral instability of the upper ankle joint]. / Therapie und Ergebnisse der frischen lateralen Instabilität am oberen Sprunggelenk.

During a retrospective study we especially examined the late outcome in therapy of injuries of the lateral capsula ligament-lesions in 210 patients. In addition we scrutinized the literature on this subject within the last 60 years, concerning the results of different therapy methods were checked. 203 collective writings on this subject, 23,279 patients and our own results achieved in the BG Accident Hospital in Murnau (Germany) all added up to 23,389 patients. We did not only observe the subjective opinion regarding the outcome of the therapy but also the socio-economic factors, such as the duration of incapability to work and do sports. Emphasis was laid on the remaining complaints: reduction of movement, swelling, pain during stress and instability (in the sense of recurring injuries). The results of this thesis show the dependence of the therapy in respect to the age of the patient. So we have developed a different therapy-concept for those under age of 30 and for those over the age of 30 years.

[Roentgen morphometry of the shoulder in diseased rotator cuff. Value of plain roentgen examination in comparison with arthroscopy]. / Schulterröntgenmorphometrie der kranken Rotatorenmanschette. Stellenwert der Nativröntgenuntersuchung im Vergleich zur Arthroskopie.

A comparison between the pathomorphological substrate and the X-ray morphometry of the shoulder joint was made with 482 arthroscopically treated patients. Radiological parameters and indices for the prediction of the development of the impingement-syndrome were developed from this comparison. With these parameters and indices is it possible to predict the pathomorphological substrate and to differentiate between subacromial and coracoidal impingement.

[The physiology of the isolated dog pancreas--the influence of the actual blood glucose level on the blood circulation in the pancreas]. / Ein Beitrag zur Physiologie des isolierten Hundepankreas--die Steuerung der Pankreasdurchblutung in Abhängigkeit vom aktuellen Blutglukosespiegel

1. Glucose loading tests were undertaken on isolated pancreas or pancreas-duodenal preparations. 2. In 75% of cases a vasodilatation can be observed which leads to enhanced blood circulation under constant pressure in the isolated organ. 3. This vasodilatation persists until the level of blood sugar has normalized. 4. The experiment being carried out on an isolated organ, external factors such as the vagus nerve, do not become active.

[Fulminant air embolism in arthroscopy of the shoulder joint using CO2]. / Fulminante Gasembolie bei einer Arthroskopie des Schultergelenkes unter Verwendung von CO2.

We report on a case of an unexpected gas embolism during an arthroscopy of a newly injured shoulder joint. We used carbon dioxide as an arthroscopic medium which has not been considered hazardous up to now. The sudden decrease of the endtidal CO2 concentration in connection with a decrease of peripheral oxygen saturation as well as the clinical symptoms led to an immediate diagnosis of gas embolism. In this case external cardiac massage and aspiration of gas from the right ventricle proved an effective treatment.

The popliteal region: an anatomical study and a new approach to the tibial attachment of the posterior cruciate ligament.

Surgical treatment of posterior cruciate ligament injuries is gaining more and more importance. The central posterior approach according to Abbott (1945) has been considered a standard, with various complications involved owing to the local anatomic conditions. This study is intended to present a modified dorsomedial approach to the posterior capsule of the knee joint that is better adapted to the anatomic conditions. As a basis, the popliteal region was dissected in 150 knee joints, and the course of the popliteal artery with its branches as well as the bifurcation of the sciatic nerve were identified. The medial joint line served as a reference point. It has been shown that the knee joint arteries and the two sural arteries arose at relatively constant levels. At least one of the meniscofemoral ligaments was found in all of the knee joints examined; the anterior ligament was present in a slightly higher percentage than the posterior ligament. The modified dorsomedial approach to the posterior joint capsule was evaluated in 50 knee joints. Dissection was achieved by blunt division of the medial head of the gastrocnemius muscle, with careful preservation of the proximal vascular supply of that muscle. It was necessary to expose neither the popliteal artery and vein nor the tibial nerve. The tibial attachment of the posterior cruciate ligament could be exposed in every knee. The advantage of the new approach to the posterior cruciate ligament described in this study consists in the preservation of the central neurovascular bundle and the excellent exposure of the tibial attachment.