[Stage-dependent arthroscopic treatment of knee joint infections]. / Stadiengerechte therapie des kniegelenkinfekts nach arthroskopie.

OBJECTIVE: The goal is early diagnostic arthroscopy with irrigation and, if needed, debridement of all 6 recesses of the infected knee joint to quickly gain control of the infection and a satisfactory functional outcome. INDICATIONS: Arthroscopic irrigation without delay is indicated even if a knee joint infection is only suspected. CONTRAINDICATIONS: No existing contraindications. SURGICAL TECHNIQUE: Arthroscopic irrigation of the knee with stage-related debridement. Particularly irrigation and debridement of the two dorsal recesses. In stage IV according to Gächter, open synovectomy and radical debridement is recommended. POSTOPERATIVE MANAGEMENT: In case of persistent infection, early revision. After removement of drainages mobilisation with continous passive motion. Antibiotic therapy is necessary even after the infection has been treated. RESULTS: Arthroscopic irrigation with stage-related debridment of all 6 recesses in combination with antibiotic therapy is the standard procedure for knee joint infections when there is no arthroplasty. Open surgery with debridement of infected bone tissue is indicated in patients with stage IV according to Gächter. Decisive for good results is an early intervention.

[Arthroscopy-assisted management of knee fractures]. / Arthroskopisch unterstütztes Frakturmanagement am Kniegelenk.

Minimally invasive and arthroscopic procedures have become an integral part of orthopedics and arthroscopy of the knee in particular has extensively evolved during recent years. Therefore, the purpose of this article is to show the indications and possibilities and also the limitations of arthroscopy-assisted fracture fixation of the knee joint. Based on the literature and our own experiences we consider the following indications for arthroscopy-assisted fracture fixation in the knee to be appropriate: 1) simple fractures of the tibial plateau, depression fractures of the tibial plateau and simple fractures of the patella, 2) arthroscopic control of reconstruction of the articular surface in complex fractures, 3) bony avulsions of the posterior or anterior cruciate ligament, 4) osteochondral flakes, 5) therapy of concomitant intra-articular lesions in fractures of the knee joint and 6) arthroscopy in posttraumatic situations. The various indications are discussed in relation to the current literature and on the basis of case reports. Arthroscopy is not only an assisting and helpful instrument in the therapy of fractures of the knee joint but in some cases it is also indispensable to guarantee optimal fracture management.

[Treatment of distal radioulnar joint osteoarthritis]. / Die Behandlung der Arthrose des distalen Radioulnargelenks.

The distal radioulnar joint (DRUJ) plays a key role in stable forearm rotation. The main stabilizer of the DRUJ is the triangular fibrocartilaginous complex (TFCC). If the integrity of the DRUJ is disturbed, commonly after distal radius fractures, osteoarthritis may develop. For the surgical treatment of osteoarthritis, different techniques are available and in most cases salvage procedures (Darrach, Bowers and Sauvé-Kapandji operations) are performed which generally promise reasonable results but include the potential risk of radioulnar instability which can lead to pain and weakness. Soft tissue stabilizing techniques have only limited success rates. In an attempt to mechanically stabilize the distal forearm following ulnar head resection various endoprostheses have been developed to replace the ulnar head. The prostheses can be used for the secondary treatment of failed ulnar head resection but can also achieve good results in the primary treatment of osteoarthritis of the DRUJ.

Facilitating training in tracheoesophageal prosthesis placement.

Success in the utilization of a tracheoesophageal voice prosthesis may be limited due to the failure to learn how to insert the prosthesis independently. Reasons that may account for this inadequacy include inadequate preoperative screening tools to assess adequacy of the insertion process and lack of the availability of a model that allows safe practice in the skills necessary for insertion and retention. To avoid these possible complications, a model has been developed that will assist the medical care team in preoperative evaluation and postoperative care.

Chromosome banding and DNA replication patterns in bird karyotypes.

The karyotypes of the domestic chicken (Gallus domesticus), Japanese quail (Coturnix coturnix), and griffon vulture (Gyps fulvus) were studied with a variety of banding techniques. The DNA replication patterns of bird chromosomes, analyzed by incorporation of 5-bromodeoxyuridine (BrdU) and deoxythymidine (dT), are presented here for the first time. In particular, the time sequence of replication of the ZZ/ZW sex chromosomes throughout the S-phase was meticulously analyzed. BrdU and dT incorporation are very useful methods to identify homoeologies between karyotypes, as well as rearrangements that occurred in the macroautosomes during speciation. The Z chromosomes of the three birds displayed the same replication patterns, indicating a high degree of evolutionary conservation. In the homogametic male, BrdU and dT incorporation revealed no evidence of asynchronous replication between euchromatic bands in the ZZ pair. The same was true of the three Z chromosomes in a triploid-diploid chimeric chicken embryo. Minor replication asynchronies between the homologous ZZ or ZZZ chromosomes were restricted to heterochromatic C-bands. These results confirm that, in the ZZ male/ZW female sex-determining system of birds, dosage compensation for Z-linked genes does not occur by inactivation of one of the two Z chromosomes in the homogametic male. The heterochromatic W chromosomes of the three species showed bright labeling with distamycin A/mithramycin counterstain-enhanced fluorescence and exhibited significantly delayed DNA replication. The nucleolus organizers of birds, frequently located in microchromosomes, were also distinguished by bright distamycin A/mithramycin fluorescence.