[Subtotal Segment Resection, Augmenting Angle-Stable Plate Osteosynthesis and Allogenic Bone Graft as Treatment Option for Juxtacortical Osteosarcoma in the Knee Region]. / Subtotale Segmentresektion, augmentierende winkelstabile Plattenosteosynthese und allogene Spongiosaplastik als Therapieoption beim knienahen juxtakortikalen Osteosarkom.

Juxtacortical osteosarcomas are a group of rare primary bone tumours. They differ from medullary osteosarcomas in their anatomic location (outside of the corticalis), low metastasis rate and better prognosis. The only evidence-based treatment of juxtacortical osteosarcomas is the wide surgical resection. In this technical report we will introduce a new surgical technique, including the subtotal resection of the tumour-bearing bone segment, defect reconstruction by means of an augmenting fixed-angle plate osteosynthesis and homologous cancellous bone graft. If necessary, a subsequent plastic coverage of the soft tissue defect was performed. The technique will be presented by means of three illustrated cases of young patients with juxtacortical osteosarcomas in the proximity of the knee joint. Following diagnostic confirmation by means of an incision biopsy and tumour staging, the three patients underwent this new surgical technique. In the postoperative follow-up and re-staging, two to seven years after surgery, all patients were under complete remission, had functionally restored knee joints (Karnofsky score 90 % or higher) and showed good aesthetic results. The surgical technique described may therefore be an adequate alternative to the complete resection of the tumour-bearing bone segment with prosthetic reconstruction and should be considered on the basis of the illustrated functional results in individual cases.

[Secondary telangiectatic osteosarcoma of the left femur. A case presentation of an unusual course of disease]. / Sekundäres teleangiektatisches Osteosarkom des linken Femurs. Darstellung eines ungewöhnlichen Krankheitsverlaufs.

BACKGROUND: This article presents the unusual case of a 73-year-old male patient who was treated with primary interlocking nailing after a pathological femoral fracture. DIAGNOSTICS: Despite comprehensive diagnostics including several biopsies, a tumor could not be detected. In 2008 when progressive cystic femoral destruction leading to loosening of the nail necessitated a partial femoral prosthesis, an osteosarcoma could first be diagnosed in the resected bone. THERAPY: Advanced progression of the tumor required an extended hip exarticulation. During the current restaging of the now 84-year-old patient no tumor could be detected. CONCLUSION: When a malignancy cannot be excluded even by repeated biopsies of radiologically suspicious structures, an adequate tumor staging followed by close monitoring should be carried out. For a clinically silent, long-term course of cystic destruction of a long bone over several years, an age over 60 years and a lack of distant metastases, an atypical osteosarcoma should be considered in the differential diagnosis.

[The impact of capsular repair on the dislocation rate after primary total hip arthroplasty: a retrospective analysis of 1972 cases]. / Der Einfluss der Kapselrekonstruktion auf die Luxationsrate nach primärer Hüftendoprothetik: eine retrospektive Analyse von 1972 Fällen.

BACKGROUND: Dislocation is the second most frequently encountered complication in primary total hip arthroplasty (THA) and occurs more commonly in the early postoperative rehabilitation phase. Sir Charnley recommended the "avoidance of resection of the capsule" and emphasised its contribution to hip joint stability in THA. Several authors, however, doubted its significance and considered resection of the capsule to be essential. Since 2002, some surgeons increasingly adopted a modified, less invasive technique of THA via Bauer approach, including the preservation and repair of the hip joint capsule with focus on maintaining its acetabular origin. Another group of surgeons applied the traditional technique including the resection of the joint capsule via an anterolateral approach. In this case-control study we investigated whether the dislocation rate can be reduced through joint capsule reconstruction and whether any negative impact on patient satisfaction, functional results or revision rate is observed. MATERIAL AND METHODS: All cases of primary THA performed in our institution in a timeframe between 2002 and 2009 were included with the only exceptions of resurfacing arthroplasty, dual mobility and tumour hip replacements. Joint capsule repair cases were gathered in the study group (SG), capsule resection cases in the control group (CG). Additional patient-related data were taken from the anaesthesia records. The WOMAC score and a questionnaire focusing on detection of dislocations and revision surgeries was sent out for each case. Further targeted research was conducted that included requesting records and reports from external hospitals. In the case of non-responding patients, all available data (operating room documentation, electronic files, archive, X-rays) were reviewed for incidents of dislocation and revision surgery. Groupings and classifications were exclusively performed by senior surgeons. SG and CG were compared regarding epidemiologic, implant-associated and surgery-specific data. Statistical evaluations were performed using the Chi-squared test and the Mann-Whitney U test. RESULTS: 1972 cases of primary THA were included: 992 in the SG and 980 in the CG. The follow-up rates were 92.7 % in the SG and 76.4 % in the CG, the mean follow-up times 33.5 months and 73.4 months, respectively, with a follow-up of at least 12 months in all cases. In the SG, the dislocation rate was 0.3 % (n = 3) and thus significantly lower than the 2.55 % in the CG (n = 25, p < 0.001). Both the WOMAC score (SG: 1.46 ± 1.73; CG: 1.53 ± 1.80; p > 0.05) and the revision rate (SG: 5.24 %; CG: 6.84 %; p = 0.139) showed no significant differences. CONCLUSION: Preservation and repair of the hip joint capsule causes an 88-%-reduction of the dislocation rate in primary THA in this large series including 1972 cases, operated via the Bauer or the anterolateral approach. Several authors reported comparable results after THA using similar techniques of soft tissue and capsular repair through the posterior or posterolateral approach. Sparing and reconstructing the hip joint capsule therefore seems to reduce the dislocation rate after primary THA by one order of magnitude regardless of the surgical approach and, especially, if the acetabular origin is preserved. Capsule-related specific complications such as an increased revision rate, malfunction or pain were neither recorded in our study nor by others. Thus, careful preservation and reconstruction of the hip joint capsule may be expressly recommended in primary THA.