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Forty-one Wagner revision stems were implanted at the Orthopedic Department of the University of Tübingen between July 1990 and January 1993. We report the results of 37 patients at an average follow-up of 27 months (13-48 months) postoperatively. The main indication was stem loosening with considerable loss of bone. In addition, we used the implant 4 times in primary arthroplasty. At follow-up examination 33 patients (89%) were satisfied with the postoperative outcome. According to the Merle D'Aubigné score (12-point scale), 32 patients showed a poor functional result of less than 6 points preoperatively. Postoperatively, the results of 36 patients could be classified as very good to good. To categorise the radiological destruction of the implant bed, we used the femoral shaft defect classification of the DGOT (Deutsche Gesellschaft für Orthopädie und Traumatologie) in conjunction with the classification of Pak and Paproski [5, 11]. Twenty patients presented with trochanteric and calcar defects, and 11 patients with a combination of a calcar and shaft defect. We found a circular shaft defect in 2 patients. In 7 cases we assessed the bone remodelling postoperatively as very good, with strong newly formed bone structures, and in 25 cases as good, with remodelling of the old stem bed and bony structuring of the osteolyses. A secondary sinking in of the Wagner stem was seen in 7 cases. Only one stem had to be revised because of pain symptoms and loosening; in all other cases a secondary stabilisation of the revision-stem took place. With the Wagner revision stem, there is the possibility of achieving mechanical stability even in situations with massive bone loss. The evacuation of bone cement and granulation tissues is facilitated by the transfemoral approach, bony remodelling is accelerated, and bone grafting is often not necessary. As our short-term results show, the concept is a promising one. Nevertheless, we will be very careful in following these patients in the long term, as we have noticed stem sinkage in a small percentage of cases.

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Introduction Soft tissue swelling of the knee joint can be caused by many diseases. Lipomas are one of the most reasonable differential diagnoses we have to consider. Therefore, we now present the uncommon case of a Lipoma arborescens (LA) and differentiate it from a quite similar manifesting spindle cell lipoma as follows. Case Report A 49-years old patient reports about progressive knee pain for four years and observes an increasing joint swelling. This swelling is a soft tissue, shiftable tumour, not painful. The magnetic resonance imaging (MRI) with contrast agent brings the diagnosis of an advanced osteoarthritis of the knee joint and classifies the tumour as LA. Subsequently, we treat the osteoarthritis by implanting a total knee arthroplasty with simultaneous intraoperative tumour resection performed as total synovectomy. The histopathological processing confirms the clinically and radiologically made diagnosis of LA. Summary Lipoma arborescens presents an uncommon subgroup of Lipomas, which is characterized by a slowly progressive increasing soft tissue swelling, especially around bigger human joints. Due to its intraarticular location, the LA might become clinically relevant when it reaches a certain tumour size. Looking at the diagnostics, sonography, MRI and especially the histopathological processing give the crucial results. Final proof can only be made by histopathological examination. Additionally, we have some differential diagnoses to exclude. Under these we predominantly find the spindle cell lipoma, synovial haemagioma, vascular synovial malformations and tenosynovial giant-cell tumour. Furthermore, an atypical lipomatous tumour should be excluded by FISH-analysis via determining the MDM2-Genamplification.

Introduction: The successful combination of osteoinductive factors with current materials used in both endoprosthetics and implantology improves bony ingrowth and long-term stability of the chosen implants. The aim of the present experimental animal study was to clarify in what way faster bony integration can be achieved through additional BMP-3-coating of titanium test implants of different surface textures (hydroxy-apatite-coated or corundum-blasted). Methods: Thirty of 60 cylindrical titanium test implants with a hydroxy-apatite or corundum-blasted surface were coated with 230 mg porcine, high-purified BMP-3-precipitate per implant to check their osteoinductive potential in a bioassay. In each case a BMP-3-coated and an uncoated control-device were implanted with a gap formation of 1 mm into the femoral part of the patellofemoral joint of the right and left leg of 30 adult giant rabbits. Serial saw slices of all explanted specimens were prepared, and the osseous integration of the implant and time-dependent bone neoformation were analyzed microscopically and histomorphometrically 14, 35, and 56 days after implantation. Results: Coating of TiAl 4 V 6 -test devices with BMP-3 led in both groups after gap implantation to an improved osseointegration, that was histomorphological and histomorphometrical verifiable. Statistical evaluation using the t-test for matched samples showed 5 weeks after surgery a significant higher volume of new formed bone of the BMP-3-coated corundum-blasted or hydroxy-apatite-coated TiAl 4 V 6 test devices compared to the non-coated controls of the same type (P < 0.01). Light microscopy demonstrated osseointegration without connective tissue membrane around the surface of the implants after 2, 5, and 8 weeks. Better osseointegration was achieved in the hydroxy-apatitecoated implants than in the corundum-blasted implants. Conclusions: Our results indicate that composite metal implants, as used in endoprosthetics and implantology, are suitable carriers for BMP-3 and improved fixation of the implants can be achieved.

From 1980 through 1991 we screwed a preshaped cortico-cancellous bone graft onto the ileum wall to compensate acetabular deficiency in 94 consecutive total hip replacements. We report the results of 87 hips (79 patients) with an average follow-up of 30 months (12-75 months) postoperatively. Pain in dysplasia-coxarthrosis and congenital dislocation of the hip, destructive coxitis in rheumatoid arthritis and cup loosening was the main indication for surgery. According to the Merle d'Aubigné score the postoperative clinical evaluation demonstrated 77% very good and 18% good results. Due to component loosening the results had to be classified as unsatisfactory in 4 hips (2 cups and 2 stems). At the time of evaluation 90% of the arthroplasties was osseously consolidated as evidenced by trabecular bridging and structural integrity with host bone. Resorptions of the graft were noted in 32 hips. One cup was removed because of complete resorption and consecutive loosening, a further one was considered clinically and radiologically loose because of partial graft resorption. Two further complete resorptions and 28 partial lateral resorptions had no influence on the secondary stability of the implant. We are aware that these are short-term results. Nevertheless, we recommend the described method as a valuable addition to arthroplasties for acetabular rim defects both in osteoarthritis and in revision surgery.

We examined the long-term results of two different methods of shoulder decompression (Neer acromioplasty and resection of the coracoacromial ligament) after an average observation period of 8 years. Clinical and radiological features were evaluated in 48 patients with 50 treated shoulders, as was the subjective result of the treatment in 58 patients with 61 operated joints. Pain was substantially eased in 93% (acromioplasty) and 100% (ligamentary resection), mobility improved in 76% and 83%, respectively. A favourable result was achieved in 86% of the acromioplasty cases and in 75% of the ligament resection cases. In one-third of the shoulders, an increasing degeneration of joint structures could be demonstrated radiologically; the degree depended on the severity of the initial rotator cuff injury, not on the method of shoulder decompression. The differences between both surgical methods examined were not statistically significant, but acromioplasty provides a superior extension of the subacromial space and protection for the reconstructed rotator cuff tendons. Our results compare favourably with other published studies. The methods described are suitable for the treatment of subacromial impingement.