[Six to ten year results of use of the alloclassic hip prosthesis--a multicentre survival analysis]. / 6 - 10-Jahres-Ergebnisse des zementfreien Alloclassic-Hüftsystems--Eine multizentrische Survival-Studie.

AIM: This prospective study describes This retrospective multicenter study was undertaken to calculate mid- and long-term survival rates of the cementless Zweymüller/Alloclassic total hip prosthesis. MATERIAL AND METHODS: The rectangular titanium stem and threaded cup have been in use since 1986. The ball head is made of alumina ceramic, the inlay of UHMW polyethylene. Five hospitals in Austria, France and Germany cooperated in the follow-up of 848 patients operated between October 1986 and September 1990 (mean age 62.2 years, 62% women, 38% men, mean patient weight 73.8 kg, body mass index 26.8). 468 patients were followed clinically, 320 patients interviewed on the phone, 29 sent a letter. No information was available concerning the remaining 31 patients. Probabilities of implant survival were estimated with the Kaplan-Meier method. RESULTS: 98 patients (11.5%) had died at a median follow-up time of 81.1 months. The probability of survival at 81.1 months was 98.6% looking at stem and cup. There was no significant association of survival of the prosthesis and patient weight, gender or body mass index. CONCLUSION: Our results are in accordance with previously published data of smaller series using the Zweymüller/Alloclassic( total hip. The survival rate of this cementless rectangular titanium prosthesis for the reported follow-up time compares favorably with contemporary cemented hip prostheses.

[Short-term results of interposition arthroplasty with autologous femur head graft combined with cement-free threaded cups for treatment of dysplastic coxarthrosis]. / Kurzfristige Ergebnisse der Interpositionsarthroplastik mittels autologem Femurkopfresektat in Kombination mit zementfreien Schraubpfannen zur Behandlung der Dysplasiecoxarthrose.

INTRODUCTION: The operative treatment of arthritis in congenital dysplastic hips (CDH) with an autologous femoral head graft is a well established technique in total joint arthroplasty. This prospective study introduces a new operative technique in which the fixation of the autologous bone graft is achieved through the threaded Zweymueller cup solely. Early results are presented. METHOD: 34 patients, (average age of 53.2 years, 24 to 74 years) with CDH had a total joint arthroplasty in combination with a femoral head autograft between 1995 and 1997 (32 patients in study). The fixation of the bone graft was achieved with screws or with a press-fit technique through the threaded cup. The results are described with an average of 2 years. RESULTS: The patients were followed prospectively for an average of 2 years. The Harris hip score increased from 32 preoperatively (range 14-61) to 82 (range 54 to 91) postoperatively. 30 hips had excellent and good results, one satisfactory and one had an unsatisfactory result. Radiographic evaluation demonstrated no osteolysis, one radiolucency was seen in Zone III of the acetabulum and heterotopic bone formation was observed in 11 of 31 radiographically evaluated hips (Brooker type I: 7, type II: 3 and type III: 1). All bone grafts achieved union, all grafts survived, and all acetabular components survived, but one. There were no complications such as dislocation, infection, nerve palsy, or a thrombo-embolic event observed. CONCLUSION: Fixation of the femoral head autograft in CDH with a threaded cup solely showed no disadvantages over the established fixation technique with screws over a short-term follow-up. A solid stable fixation of the graft with a threaded Zweymueller cup was achieved and resulted in full graft integration without the use of screws.

[Highly malignant telangiectatic osteosarcoma. Long-term follow-up]. / Hochmalignes teleangiektatisches Osteosarkom. Langjährige Verlaufsbeobachtung.

The teleangiectatic osteosarcoma is an extremely malignant tumor of the bone with rapid progression and short time of survival. In a 57 y.o. male such a tumor in the right proximal femur was diagnosed. Previously for 13 years a cystic bony lesion was known and followed in consequent intervals radiologically and clinically. There was no change in appearance till all at once malignant change developed. Systemic bone disease as ethiopathogenetic factor (e.g. ostitis deformans Paget) could be excluded. This case demonstrates an uncommon development of a teleangiectatic osteosarcoma out of a radiologically benign bony cyst, consequently followed for 13 years.

Quantitative measurement of disc space area before and after chemonucleolysis and nucleotomy.

Measurements of the area of the intervertebral disc space were made, over a period of 400 days or more, in 16 patients who underwent chemonucleolysis and 20 patients after nucleotomy. The superimpositioning method of measurement used is based on a determination of fixed points and it has a high level of reproducibility. We have measured areas which differ from volumes in only a single dimension, but which show good correlation compared with measurement of intervertebral disc space heights alone. After both chemonucleolysis and nucleotomy, narrowing of the intervertebral disc space occurs up to the 50th day, after which there is a highly significant difference: the intervertebral disc space height increases after chemonucleolysis, and continues to decrease after nucleotomy. It is concluded that the enzymatic effect of chymopapain on the nucleus pulposus produces a gain in disc substance after chemonucleolysis, whereas nucleotomy is associated with a loss of substance.

[The tenodesis of the peroneus muscle for the treatment of the chronic insufficiency of the lateral ligaments of the upper ankle joint (author's transl)]. / Traitement de l'instabilité tibio-tarsienne par ténodèse à l'aide du court péronier latéral.

Thirty-eight cases presenting with chronic instability of the ankle joint have been examined. Tenodesis using peroneus brevis has given satisfactory results in 29 cases and poor results in 9 cases (after the method of assessment by Weber). We have classified instability of the ankle joint in a functional way from Types I to III. In Type III, an extended form of tenodesis is required.

[Histological and Histomorphometric Changes after Osteotomies of Rabbit Tibiae Treated with Plate Osteosynthesis (author's transl)]. / Histologische und histomorphometrische Veränderungen bei Plattenosteosynthesen nach Osteotomien an der Tibia des Kaninchens

In all specimens the cross-sections of bone taken at 4 marked points showed atrophy of the cortical bone which had occured in a typical manner. In the 1-week specimens no qualitative changes could be observed by normal light microscopy. In the 2nd week, however, a vivacious bone remodelling with wide Haversian canals and vessels starts from the medial cortex as could be seen identically in every series of our experiments. In the 4th week and especially in the 6th week it becomes also apparent on the lateral, dorsal and ventral wall. In the 12th week bone remodelling is still active but obvious diminishing of the osteons can be observed between internal and external lamellae. In the 24th week only solitary enlarged sinus and few osteons are found medially and laterally. Alltogether the cortical bone has become very thin. The bone remodelling has stopped and this state is characterized by loss of osteons and abundance of intermediate lamellae. Already in the 1st week polarisation microscopy shows a certain demascating of the collagenous fibres opposite to the plate. The control specimens do not show changes of the collagenous structure in this area. In addition to these results histomorphometric investigations of 1-week specimens revealed a quantitative increase of Haversian canals which are located closer to the medullary space as well as to the side opposite the plate. This result is due to the fact that the bone remodelling starts from the cortex opposite to the metal implant.