Measurement and comparison of individual external doses of high-school students living in Japan, France, Poland and Belarus-the 'D-shuttle' project

Twelve high schools in Japan (of which six are in Fukushima Prefecture), four in France, eight in Poland and two in Belarus cooperated in the measurement and comparison of individual external doses in 2014. In total 216 high-school students and teachers participated in the study. Each participant wore an electronic personal dosimeter 'D-shuttle' for two weeks, and kept a journal of his/her whereabouts and activities. The distributions of annual external doses estimated for each region overlap with each other, demonstrating that the personal external individual doses in locations where residence is currently allowed in Fukushima Prefecture and in Belarus are well within the range of estimated annual doses due to the terrestrial background radiation level of other regions/countries.

[Total hip arthroplasty and femoral head osteonecrosis in renal transplant recipients]

PURPOSE OF THE STUDY

Osteonecrosis of the femoral head is reported in a very variable proportion of renal transplant recipients. When these patients require total hip arthroplasty (THA), immunosuppression and poor bone quality increase the risk of aseptic loosening and infection. In the literature, functional outcome has been satisfactory although rates of early and late complications have varied greatly. The purpose of our work was to determine the long-term outcome in a series of renal graft recipients who underwent THA for osteonecrosis of the femoral head.

MATERIAL AND METHODS

Forty-eight THA were implanted for aseptic osteonecrosis of the femoral head (Ficat grade III and IV) in 32 renal transplant recipients between 1974 and 1995 (21 men and 11 women). Mean age was 30 years at transplantation and 39 years at THA surgery. Thirty patients had been on hemodialysis for a mean 1 year prior to transplantation. Joint disease concerned 2 or more joints in 23 of the 32 patients. Fifteen hips had a surgical history: 8 drillings and 3 head arthroplasties. The THA was implanted under general anesthesia via the posterolateral approach. All implants were fixed with a gentamycin cement. A cephalosporin was used for the antibiotic prophylaxis in 20 cases and a cephalosporin/vancomycin combination in 24. Functional outcome was assessed with the Postel-Merle-d'Aubigné (PMA) score. Functional gain was [(PMAreview-PMApreop)/PMApreop]. General or local complications were recorded at last follow-up. The complete or incomplete nature of lucent lines seen on the last follow-up x-rays and their evolution were also recorded. Reasons for second procedures were noted.

RESULTS

Early complications were: phlebitis (n=1), hematoma (n=7), dislocation (n=1), deep infection (n=2). At last follow-up (mean=5 years 7 months), four patients (6 THA) had died and six (7 THA) were lost to follow-up. Preoperatively, function was scored fair or poor in 91% of the patients. At last follow-up function was scored good, very good, or excellent in 75%. Mean functional gain was 38%. A second operation was necessary for seven THA due to aseptic loosening (mean delay 9 years 10 months), for five others for septic loosening (mean delay 6 years 8 months), and finally for two for instability (one early and the other after more than 2 years). In all, 29% of the THA were reoperated. Two deaths were related to late THA infection. Active lucent lines were observed in 11% of the THA (excepting patients reperated for loosening).

DISCUSSION

The functional gain provided by THA in renal transplant recipients with aseptic osteonecrosis of the femoral head is clearly established. Implant survival remains a problem. The rate of early local complications was high in our series, mainly related to hematoma formation and infection. The infections observed were particularly severe requiring early comprehensive management at onset of clinical signs. For patients with suspected deep infection, we propose an aspiration biopsy of the joint to obtain a bacteriological sample.

CONCLUSION

THA enables good functional outcome for renal transplant recipients suffering from osteonecrosis of the femoral head, but at the cost of a high risk of early and long-term complications not always reported in the literature.

Wrist arthroscopy and dislocation of the radiocarpal joint without fracture

The authors report a rare case of dorsal dislocation of the radiocarpal joint without any bony lesion associated. The traumatic cause was a high energy motorbike accident. Fractures of the other limbs were associated. The authors report the clinical, radiological, and arthroscopic features. Wrist arthroscopy showed a complete tear of all the extrinsic ligaments, a radial avulsion of the triangular fibrocartilage complex, and the integrity of the intracarpal ligaments, which guided the treatment. The dislocation was treated by closed reduction and radiocarpal pinning. The authors propose wrist arthroscopy in radiocarpal dislocation for diagnosis of soft tissue and cartilaginous lesions to guide the treatment (close or open).

Coral grafting supplemented with bone marrow

Limited success in regenerating large bone defects has been achieved by bridging them with osteoconductive materials. These substitutes lack the osteogenic and osteoinductive properties of bone autograft. A direct approach would be to stimulate osteogenesis in these biomaterials by the addition of fresh bone-marrow cells (BMC).

We therefore created osteoperiosteal gaps 2 cm wide in the ulna of adult rabbits and either bridged them with coral alone (CC), coral supplemented with BMC, or left them empty. Coral was chosen as a scaffold because of its good biocompatibility and resorbability. In osteoperiosteal gaps bridged with coral only, the coral was invaded chiefly by fibrous tissue. It was insufficient to produce union after two months. In defects filled with coral and BMC an increase in osteogenesis was observed and the bone surface area was significantly higher compared with defects filled with coral alone. Bony union occurred in six out of six defects filled with coral and BMC after two months. An increase in the resorption of coral was also observed, suggesting that resorbing cells or their progenitors were present in bone marrow and survived the grafting procedure. Our findings have shown that supplementation of coral with BMC increased both the resorption of material and osteogenesis in defects of a clinical significance.

Coral grafting supplemented with bone marrow

Limited success in regenerating large bone defects has been achieved by bridging them with osteoconductive materials. These substitutes lack the osteogenic and osteoinductive properties of bone autograft. A direct approach would be to stimulate osteogenesis in these biomaterials by the addition of fresh bone-marrow cells (BMC). We therefore created osteoperiosteal gaps 2 cm wide in the ulna of adult rabbits and either bridged them with coral alone (CC), coral supplemented with BMC, or left them empty. Coral was chosen as a scaffold because of its good biocompatibility and resorbability. In osteoperiosteal gaps bridged with coral only, the coral was invaded chiefly by fibrous tissue. It was insufficient to produce union after two months. In defects filled with coral and BMC an increase in osteogenesis was observed and the bone surface area was significantly higher compared with defects filled with coral alone. Bony union occurred in six out of six defects filled with coral and BMC after two months. An increase in the resorption of coral was also observed, suggesting that resorbing cells or their progenitors were present in bone marrow and survived the grafting procedure. Our findings have shown that supplementation of coral with BMC increased both the resorption of material and osteogenesis in defects of a clinical significance.

[Knee fractures in the adult]

In the adult, fractures of the knee are joint fractures. The knee is a weight-bearing joint, and its mobility and stability must be recovered quickly for good functional recuperation. Aside from X-ray investigations, the initial examinations seek vascular, nerve and cutaneous lesions. The existence of a bruise or a cutaneous break decides the therapeutic choice and timing. Fractures of the lower extremity of the femur (sub-, inter-, supra- or unicondyle) most often require open surgery for better restitution of the joint surfaces; for fractures of the tibial plate, whether uni-, spino- or bituberous, a graft must be associated in case of crushing fracture. Fractures of the patella require surgery in case of rupture of the extensor.