Introduction: Due to an increase in survival skeletal metastasis becomes a significant factor on life quality in carcinoma patients. Also shown in publications of the last years the surgical approach and the expected prognosis are very much based on the primary. Especially patients with breast carcinoma show very long survival times, which must be considered in choosing the adequate surgical approach. Aim of this study was to proof that on a large collective of consecutively treated patients.

Methods: Between 1980 and 2005 115 patients with metastatic disease to the bone due to breast carcinoma had been surgically treated. In 112 female and 3 male the mean age at surgery was 58 years (17–84 years). Retrospectively location and extension of the disease, symptoms, surgical approaches, complications, recurrencies and survival time had been evaluated.

Results: The most often peformed procedure was a decompression with or without stabilisation of the spine in 42 cases. Four vertebroplasties had been additionally performed. The proximal femur had to be reconstructed with an endoprotsthetic device in 24 cases, an endoprostehtic reconstruction of the humerus was necessary in 2 patients, of the pelvis in one case. One diaphyseal prothesis was implanted. Two resctions/amputation without any reconstruction had to be performed. In 20 cases a compound osteosynthesis, in 19 cases a biopsy only was done. In most of the cases postsurgical radiation was administered in some cases preoperative radiation had been applied. Follow-up was done 1 to 26 years after surgery (average 11.7 years).

Many pateints showed an extented survival despite disseminated disease with a high and quality of life. Radical resection as tried in a few patients did not proof to be beneficial regarding the prognsotic effect.

Conclusions: Patients with skeletal manifestations of breast carcinoma showed long survival times despite extented disease. The intralesional surgical approach including radiation therapy showed a better functional outcome in comparison to radical procedures with no disadvantage in survival time or local recurrencies.

Introduction: In a photoelasticimetric model Ondrouch suggested a correlation between stress in arthritic joints, microfractures and bone cysts. Other authors believe in a causative role of access of joint ßuid to bone in periarticular osteolysis. In our opinion mechanical stress induced by cartilage defects induces microfractures followed by cystic bone degradation. Materials and Methods: A þnite element analysis using the well described parameters for cancellous and cortical bone as also cartilage was performed. Several typical situations of localized and general cartilage pathologies were calculated in a schematic hip joint situation. Results: A signiþcant impact of cartilage defect size and resulting stress distribution correlating well to cystic lesions of patients with osteoarthritis of the hip could be shown. In localized cartilage defects max. stress was calculated at the rims of the lesions in the subchondral bone. Assuming a situation with an allready preformed cyst either in the acetabulum or the femoral head, further enlargement of the cyst will appear due to a maximal stress at the rims of the lesions. Femoral lesions have a comparable small tendency to grow, thereas acetabular lesions will grow rapidly. Discussion and Conclusion: These þndings þt very well with the clinical observations. Cartilage lesions inducing microfractures by mechanical stress may be able to explain the process of subchondral cyst formation. A process involving osteoclasts and myxomatous cells within the bone marrow seems to be a subsequent mechanism of remodelling and formation of myxomatous cyst content.