The aim of the study to analyze the circulating white blood cells including the intensity expression of surface receptors and cytoplasmic molecules in patients underwent total hip replacement, with either aseptic or septic loosening of hip prostheses in order to identify cell-surface and cytoplasmic markers that could be indicative of early loosening. Flow cytometry was performed in whole peripheral blood samples of 20 patients with loosening (10 septic and 10 aseptic). Ten healthy individuals served a control group. The CD62L, CD18, CD11a, CD11b and CD11c expressions were evaluated. The mean fluorescence intensity (MFI) of CD 18 was decreased on all leukocytes subsets compared to control group. For patients with aseptic loosening we demonstrated an increase of MFI for CD11b in granulocytes and for CD11c in monocytes and granulocytes compared to control group. In patients with septic loosening an increase of MFI for CD 11c was observed in monocytes compared to control group. The comparison between aseptic and septic loosening showed a statistically significant lower CD18 MFI value in granulocytes for aseptic loosening. A trend towards lower MFI values of CD 62L in lymphocytes and granulocytes were observed in aseptic but not in septic loosening patients compared to control group. The present study is the first study in published literature to demonstrate cell surface and cytoplasmic markers in peripheral blood indicative of loosening of THAs by means of flow cytometry.

Of 3000 patients diagnosed with primary malignant bone tumours and treated at our unit over the past 25 years, 234 (7.8%) were considered to be spindle cell sarcomas of bone (ie not osteosarcoma, chondrosarcoma, Ewing’s, chordoma or adamantinoma). We have analyzed their management and outcomes.

The diagnosis of these cases varied with fluctuations in the popularity of conditions such as MFH, fibrosarcoma and leiomyosarcoma with the passage of time. Treatment was with chemotherapy and surgery whenever possible. 36 patients had metastases at diagnosis and 17 had palliative treatment only because of age or infirmity. The most common site was the femur followed by the tibia, pelvis and humerus. The mean age was 45 and the mean tumour size 10.2cm at diagnosis. 25% of patients presented with a pathological fracture. Chemotherapy was used in 70% of patients the most common regime being cisplatin and doxorubicin. 35% of patients having neoadjuvant chemotherapy had a good (> 90% necrosis) response. The amputation rate was 22% and was higher in patients presenting with a fracture and in older patients not having chemotherapy.

With a mean follow up of 8 years the overall survival was 64% at 5 yrs and 58% at 10 yrs. Adverse prognostic factors included the need for amputation, older age and poor response to chemotherapy as well as a pathological fracture at presentation. The few patients with angiosarcoma fared badly but there was no difference in outcomes between patients with other diagnoses.

We conclude that patients with spindle cell sarcomas should be treated similarly to patients with osteosarcoma and can expect comparable outcomes. The histological diagnosis does not appear to predict behaviour.

Antigranulocyte scintigraphy with the use of monoclonal antibodies or antibody fragments (leukoscan) is a promising diagnostic tool that has been used widely during the recent years for the establishment of prosthesis infection after total hip or knee arthroplasty.

In the present study we report the Ioannina University Hospital experience in the diagnostic efficacy of leukoscan for the diagnosis of prosthesis infection in patients with total hip or knee arthroplasty.

We considered all patients with suspected total hip or knee arthroplasty infection that had undergone a leukoscan examination for the diagnosis of this infection in our department during the year 2004. All patients underwent a 3-phase bone scan and a subsequent leukoscan. For the whole group of patients the sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy were calculated by comparison of the results of three-phase bone scan or leukoscan with the results obtained from cultures of synovial fluid obtained from articular puncture or cultures of intraoperative sampling from those patients that had undergone a revision surgery.

A total of 19 patients with total joint arthroplasty (12 THA and 7 TKA) and suspected prosthesis infection were included in the study. The mean age of patients was 67 years. Twelve patients had verification of prosthesis infection in cultures. The overall sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy for the three-phase bone scan were 54%, 83%, 88%, 45% and 63% respectively. On the contrary, the overall sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy for leukoscan were 75%, 86%, 90%, 66% and 79%, respectively.

Antigranulocyte scintigraphy with the use of monoclonal antibody fragment sulesomab (leukoscan) had good but not perfect diagnostic performance for the diagnosis of prosthesis infection in patients with total hip or knee arthroplasty.