Results of the anatomic cementless prosthesis with different types of hydroxyapatite coating.

This study evaluates the clinical and radiographic results and the bone-implant osteointegration obtained with the Anatomic (Zimmer, Warsaw, Ind) cementless total hip prosthesis using three different types of surface coating. Two hundred twenty-seven patients underwent total hip arthroplasty using the Anatomic prosthesis. Patients were divided into groups based on the type of surface coating: in group A (69 patients), prostheses were uncoated; in group B (90 patients), the metaphyseal region of the prostheses was coated with calcicoat (a mixture of hydroxyapatite and tricalcium phosphate) (Zimmer); and in group C (68 patients), the fiber mesh and proximal stem of the prostheses were coated with calcicoat. Prostheses coated with calcicoat yielded better clinical and radiographic results than uncoated prostheses, especially in regard to thigh pain. No significant difference was observed between groups B and C. These results obtained with the Anatomic prosthesis are promising and encourage the use of implants coated with calcicoat.

[Clinical usefulness of a computerized tomography study of morphology of the femoral canal in patients candidates for hip prosthesis]. / Utilità clinica dello studio con tomographia computerizzata della morfologia del canale femorale nei pazienti candidati a protesizzazione dell'anca.

In the last few years hip arthroplasty has been increasingly used and both metaphysis and diaphysis of the proximal femur are studied preoperatively for best compliance between prosthesis and bone. Indeed, the best results can be obtained by reducing the risk of stem end mobilization, which means to choose the prosthesis fitting the femoral canal best and to limit the use of cement prostheses, which are at high risk of mobilization in time, to advanced osteoporosis patients. We used a simple and repeatable CT technique to study femoral canal structure and size. After accurately positioning the patients inside the gantry, we acquired some axial scans at scheduled levels referring to the horizontal midline of the lesser trochanter. The axial scans were acquired 2 cm above and 5 and 10 cm below the horizontal midline in 105 patients. Measurements were bilateral in 13 patients. Finally, the results were compared with the surgical outcome. Femoral canal cross-diameters and cortical bone width varied greatly, which variations were confirmed in bilateral measurements and in the same patient between the two femurs. Femoral canal structure, which can be remodelled, influences the choice of the stem and thus the amount of cement. We believe this method to be fundamental for correct surgical planning and for best treatment outcome.

Prophylaxis against deep-vein thrombosis in total hip replacement. Comparison of heparin and foot impulse pump.

We performed a randomised controlled study to compare heparin with the A-V Impulse System in the prevention of deep-vein thrombosis (DVT) in 132 consecutive patients undergoing total hip replacement. After the operation, all patients had compression stockings, 65 were treated with calcium heparin and 67 with the intermittent plantar pump. DVT was diagnosed by Doppler ultrasound and thermography, followed by phlebography. There were 23 cases of DVT (35.4%) in the heparin group, with 16 major and seven minor thromboses. In the impulse pump group there were nine cases (13.4%) with three major and six minor thromboses. The differences for all thromboses and for major thromboses were both significant at p < 0.005. In the heparin group there was one fatal pulmonary embolism and nine patients (13.8%) had excessive bleeding or wound haematomas, as against none in the impulse pump group.

The responsiveness of bone metastases to radiotherapy: the effect of site, histology and radiation dose on pain relief.

281 patients with a total of 463 symptomatic osseous metastases treated for palliation between 1975 and 1985 have been retrospectively analysed. The most frequent primary sites were breast (50.1%) prostate (16.6%) and lung (11%), accounting for more than three fourths of all metastatic areas. Other primaries were represented by bladder, kidney, colorectal, uterus (corpus and cervix) melanoma and thyroid tumors, and by cancer from unknown origin. Palliation was evaluated only on a subjective pain score. Complete response meant complete pain relief, and partial response meant more than 50% and less than complete pain relief in all treated sites. Complete response rates were similar independently from the primary site, except for the adenocarcinomas of the kidney and for non-small cell carcinomas of the lung in which the response tended to be lower. A correlation was also found between the incidence of pain relief and the site of bone metastases, in that a lower response was shown in limb localizations. Also, the number of metastatic sites did not influence the complete response rate. As expected, the response rate in all cases seemed to be dependent on total absorbed dose while, surprisingly, it could not be shown to be affected by the fraction size. A similar trend was shown for the pain recurrence.

[Osteosarcoma. A new diagnostic approach in presurgical loco-regional staging]. / Osteosarcomi. Nuovo approccio diagnostico nello staging loco-regionale pre-chirurgico.

The value of Magnetic Resonance (MR) imaging was examined in the anatomical staging of bone osteosarcomas. Eleven patients were studied--8 central and 3 parosteal osteosarcomas. The accuracy of MR imaging was compared to that of plain film, scintigraphy, CT, and angiography. MR imaging was superior to both CT and radionuclide scanning in defining intramedullary extension and in showing skip metastases. Cortical erosion in central osteosarcomas was demonstrated by MR imaging, CT, and plain film; in 1 case of parosteal osteosarcoma MR imaging was superior to CT in showing cortical penetration. In two cases MR imaging did not accurately demonstrate the relationship of the tumor to the major vessels; only angiography showed vascular involvement. MR imaging was useful in delineating extraosseous extension. The importance is stressed of a correct use of MR imaging towards an accurate diagnosis. In fact, intramedullary extension and skip metastases were better demonstrated on T1-weighted images with large fields, while T2-weighted images and small fields were needed for the best overall evaluation of extraosseous involvement. In conclusion, MR imaging should be used for preoperative staging of osteosarcomas in those cases where diagnosis was made on the basis of clinical, radiographic, and bioptic findings.

Treatment of solitary bone cysts with intramedullary nailing.

The article describes the treatment of solitary bone cysts of the upper and lower limbs by means of elastic intramedullary nailing. In the 11 cases treated, bone rehabilitation was complete, probably due to the defluction of the intracystic fluid by means of the drainage caused by the nails.

[Chondrosarcoma of the bone. Differential pre- and postoperative diagnosis using magnetic resonance]. / Condrosarcomi dello scheletro. Diagnostica differenziale pre- e post-operatoria con Risonanza Magnetica.

Twelve patients were studied by means of Magnetic Resonance Imaging (MRI) in order to demonstrate either loco-regional recurrence of central chondrosarcomas or degenerative evolutions of exostoses. MRI findings were compared with plain film, scintigraphy, and Computed Tomography. MRI showed loco-regional recurrences by demonstrating their site, extent, and relationship with adjacent structures. In showing the degenerative evolution of exostoses MRI--confirmed at surgery--was superior to plain film in 3 cases out of 7, and to Computed Tomography in 2 cases. The authors discuss MRI findings: chondrosarcomas have low-intensity signal in T1-weighted sequences and high-intensity signal in T2-weighted. Thanks to its high contrast resolution MRI always allowed the detection of the chondrosarcoma. Nevertheless, MRI did not allow the tumor grading--which is due either to a difficult evaluation of the morphology of neoplastic calcifications, or to non-specific-intensity signal.

Dynamic endomedullary nailing in the treatment of extensive bone cysts in young patients. A pathogenetic interpretation.

The authors discuss the treatment of 6 cases of extensive bone cysts in young patients (10-18 years of age) by elastic endomedullary nailing, all of which were successful, with complete remodelling of the bone. They advance the hypothesis that this was probably due to dispersion of the fluid by drainage along the nails, followed by natural remodelling in these young patients. The technique is illustrated. The advantages claimed are its simplicity of execution, and the reliability of the results.

Idiopathic chondrolysis of the hip: an ultrastructural study of the articular cartilage of the femoral head.

Core biopsies obtained from the articular cartilage of the femoral head of a 16-year-old girl with idiopathic chondrolysis of the hip were subjected to an ultrastructural study. Zone I was missing and zone II was the most superficial layer present in the articular cartilage of our patient. Collagen fibrils were thinner than normal and more uniform in diameter, and proteoglycans were normally distributed among them. Degenerating chondrocytes were found, as well as debris of dead cells, but many chondrocytes were still vital and engaged in active synthesis. Most of the chronic degenerative changes observed in ultrastructural studies on osteoarthritis were not observed in this case of idiopathic chondrolysis which seems to be, on the basis of our findings, a pathological process which develops and runs its course very quickly.

Segmental amputation with re-implantation in the treatment of malignant bone tumours of the limbs.

Stage 2 B malignant skeletal tumours are currently treated by amputation or disarticulation of the limb. The present paper describes a surgical technique for complete removal of the neoplasm and surrounding soft tissues by resection of a cylinder of the limb complete with skin. The resection of bone and adjacent soft tissues is extended sufficiently proximal and distal to the neoplasm to ensure complete removal of neoplastic tissue. The authors describe two cases; an osteosarcoma of the distal third of the femur and a malignant fibrous histiocytoma of the lower radius. After removing the affected cylinder of the limb, osteosynthesis is performed by one of a variety of methods. The main vessels and nerves are dealt with according to the findings revealed by pre-operative investigations or per-operative findings. If they have to be sacrificed, end to end suture is performed, but if main nerves can safely be spared (as in Case 1) it greatly enhances the functional prognosis. The value of this operation is that it is as radical as amputation while the aesthetic and functional results are equivalent to those of a resection-arthrodesis. The operation has therefore been designated segmental amputation.

Diabetic neuroarthropathy of the foot.

The authors describe 5 cases of diabetic neuroarthropathy of the foot that came under their observation. They report the clinical radiological and histological findings and discuss the most widely accepted pathogenetic theories, including their own, based on their histological data. They also outline a programme of treatment and prophylactis measures to be adopted in these cases.

Resection and reconstruction of the distal end of the femur or proximal end of the tibia after radical excision of diaphyseal and epiphyseal segments.

The authors describe a technique of bone reconstruction after radical resection of bone segments from the distal end of the femur or proximal end of the tibia. This involves the insertion of an intramedullary nail of predetermined length which is fixed to the bone by screws applied at the proximal and distal ends of the nail. An aiming device is used which permits the screws to be applied by a closed procedure. The reconstruction is effected by using the diaphysis of the contralateral fibula, which is divided longitudinally into two halves. These are then applied laterally and medially to the endomedullary nail at the site of the resected area. Grafts of cortico-spongy bone taken from the iliac crests are inserted between the two fibular hemidiaphyses. The authors give a detailed description of the operation and report the clinical results obtained in eleven cases and the complications observed.

Antiblastic hyperthermic regional perfusion in the treatment of malignant neoplasms of the limbs.

The authors describe the theoretical principles and the experimental and clinical investigations that form the basis for the technique of selective hyperthermic perfusion of the limbs, with or without the addition of antiblastic agents. Neoplastic cells are much more sensitive to heat than normal cells, undergoing necrosis at a temperature of 42.5 to 43 degrees C. The authors discuss the histological appearances and the clinical results obtained in the treatment of 29 cases of malignant neoplasms of the limbs in which antiblastic hyperthermic perfusion was carried out one month before surgical removal of the neoplasm. The long term results show that antiblastic hyperthermic perfusion significantly reduces the risk of local recurrences in cases of resection and in some cases enables amputations rather than disarticulations to be performed. This type of treatment is particularly indicated in the highly undifferentiated and aggressive forms such as osteosarcoma, malignant fibrous histiocytoma, adamantinoma, fibrosarcoma, giant-cell sarcoma, Ewing's tumour, and synovioma.

[Histological changes induced in normal and neoplastic cells by hyperthermia associated with high energy radiation]. / Considerazioni sulle modificazioni istologiche indotte sulle cellule normali e neoplastiche dall'ipertermia associata a radiazioni ad alta energia.

The Authors refer about the treatment of neoplastic tissues (osteosarcomas) by microwave hyperthermia associated with radiation therapy. They used a diathermy device working at 27 MHz, and a linear accelerator at 5.7 MeV. They studied histologically the degree of necrosis, and saw that necrosis is obtained also by smaller amount of rads than habitual, but necrosis was not diffuse uniformly: just some zone were vital. The Authors suggest indications of the method, and remark the technical problems of the same.