S. Arita

The aetiology and treatment of simple bone cysts

The internal pressure of simple bone cysts was found to be slightly higher than the normal pressure of the bone marrow in the contralateral limb. The pressure within the cyst was measured during drilling with a Kirschner wire; it gradually decreased as the number of drill-holes increased. The PO2 of the cyst fluid was markedly lower than that of either venous or arterial blood measured synchronously. It is suggested that venous obstruction in the bone is the likely cause of these cysts. Seven patients with simple bone cysts were treated by the multiple drill-hole method, and the clinical outcome was excellent. Multiple drilling may prove to be the treatment of choice for simple bone cysts in the younger patient, as it presents fewer hazards than other procedures.

Simple bone cysts treated by multiple drill-holes 23 cysts followed 2–10 years

We treated 23 simple bone cysts by the multiple drill-hole method and reviewed them a mean of 5 (2-10) years later. 11 cysts were located in the humerus, 9 in the femur, 2 in the tibia, and 1 in the pubis. The cysts recurred in 15 cases after the initial operation. 12 recurrent cysts were treated with reoperations. At the follow-up, good bone formation with no sign of recurrence was seen in 15 cases. A residual cyst was found in 8 cases, but further treatment was not considered necessary.

Possible cardiac side effects of granisetron, an antiemetic agent, in patients with bone and soft-tissue sarcomas receiving cytotoxic chemotherapy

The cardiac effect of granisetron, a selective 5-hydroxytryptamine3 receptor antagonist, on 12 patients with bone and soft-tissue sarcomas treated by cytotoxic chemotherapy consisting of multiple courses was examined. Of the 12 patients, 4 showed significant electrocardiographical changes, including sinus bradycardia, integral change of P-waves, junctional escape beat, and atrioventricular (AV) block with Wenckebach phenomenon, indicating stimulatory regulation of the vagus nerve. These changes were observed in each patient after several courses of chemotherapy but not in the first course. There was no correlation between the electrocardiographical changes and the chemotherapeutic agents used or the type of tumor present. A patient with osteosarcoma showed persistent bradycardia in three courses, all protocols of which contained high-dose methotrexate. From these findings we conclude that the cardiac responses may be due to stimulated activity of the vagal efferent nerve, which is regulated reflexly by afferent nerve activity suppressed by granisetron. On the other hand, the antiemetic efficacy of granisetron was satisfactory. These results suggest that careful observation of the heart is necessary when granisetron is used, especially for chemotherapy consisting of repeated multiple courses.

Radiological evidence of healing of a simple bone cyst after hole drilling

SummaryWe report the long-term results with ten patients with simple bone cysts with special retrospective reference to the radiographic evidence of healing after hole drilling. Cortical thickening was initially observed within 3 months, and minimal new bone formation around Kirschner wires left in situ was observed within 4 months. New bone formation gradually progressed from the cyst wall and around the wire. Consolidation of a cyst cavity was uniformly observed 6–7 months after drilling. In several patients residual cysts were seen between the wire and cortical shell. In younger patients, a cystic cavity reappeared after extraction of the wire, although complete radiographic healing had been observed. These findings suggest that a Kirschner wire plays an important role in preventing relapse of simple bone cysts after hole drilling.

A case of multiple simple bone cysts

SummaryWe report a case of multiple, simple bone cysts in long tubular, short tubular, and flat bones. The internal pressure of the cysts and the oxygen tension of cyst fluid were measured simultaneously. These values were similar to those of typical solitary cysts in other patients. Curettage and bone graft onto the calcaneal cyst were effective, although steroid injection therapy into the metacarpal cyst had no effect. Piercing the ulnar and radial cysts a number of times was uniformly effective. These results may suggest that venous obstruction of the lesions play an important role in the etiology of multiple simple cysts, as shown in typical bone cysts. However, we could not exclude the possibility that simple bone cysts, solitary or multiple, represent some kind of secondary forms of other disorders, or that a simple bone cyst is a heterogeneous entity.ZusammenfassungEs wird über einen Fall von multiplen Knochenzysten berichtet, die sowohl in langen und kurzen Röhrenknochen als auch in platten Knochen lokalisiert waren. Simultane Messungen des Zystenbinnendruckes und der Sauerstoffspannung der Zystenflüssigkeit ergaben ähnliche Werte wie bei typischen solitären Knochenzysten. Kürettage und Knochentransplantation waren bei der Kalkaneuszyste erfolgreich, während die Steroidinjektion in die Metakarpalzyste keinen Effekt hatte. Multiples Anbohren der Ulna- und Radiuszysten war in gleicher Weise effektiv. Diese Resultate lassen vermuten, daß auch in der Ätiologie der multiplen Zysten möglicherweise die venöse Abbflußbehinderung eine wichtige Rolle spielt, wie dies für typische solitäre Knochenzysten gezeigt werden konnte. Es kann jedoch die Möglichkeit nicht ausgeschlossen werden, daß einfache Knochenzysten, solitär oder multipel, so etwas wie eine sekundäre Form anderer Erkrankungen darstellen oder daß es sich bei den einfachen Knochenzysten doch um eine heterogene Gruppe von Veränderungen handelt.

Aneurysm of a persistent sciatic artery

Abstract We report a case of an aneurysm of a persistent sciatic artery which caused buttock pain. Preoperative diagnosis is very difficult. However, awareness of the presence of this rare embryonic abnormality is important, especially in elderly persons with atherosclerotic changes. Sagittal magnetic resonance imaging (MRI) was very useful in reaching this diagnosis.

Murine fibrosarcoma clone established in defined medium.

Dear Editor: Using serum-free, chemically defined media, growth factors, carbohydrates, and hormones have been analyzed in regard to their biological properties (5,6,11,14,18). Serum-free media are also important to demonstrate the mechanism of cell replication, since exogenous growth stimulation can be arranged (6,11,14,18). On the other hand, complete protein-free cell culture is essentially different from serum-free culture, since serum supplementation including peptide hormones, growth factors, and transferrin have been used popularly in serum-free culture. In order to analyze the growth mechanism of cells, it is necessary to establish cell lines which grow exponentially in protein-free medium, since exogenous growth factors are completely excluded in this system. However, complete protein-free media are not as common as serum-free media (12,15,16), since not many cells are able to grow in a proteinfree environment. In fact, long-term protein-free culture has been reported only by several authors (7,9,12). To our knowledge, there have been no reports on the establishment of a fibresarcoma clone that grows in protein-free medium. It is important to establish such a clone to demonstrate its growth and differentiation, since it is likely that the different types of cells show different processes of growth and differentiation. This report describes the estabhshment of a fibrosarcoma clone grown in a protein-free medium exponentially. Gunma clone-4 (Gc-4 SD) was established from RCT (Radiological-Ciba-Toyama) sarcoma which arose spontaneously in a C3H/ He mouse presented by Dr. S. Tatezaki, Department of Orthopedic Surgery, Toyama Medical and Pharmaceutical University, by the limiting dilution method used in our laboratory (1). Gc-4 SD expressed major histocompatibility antigens and Fc receptor without tumor-specific transplantation antigens. Its high metastatic capacity was evident in natural and experimental metastases (1,17). Histologic findings demonstrated that the clone was basically a fibrosarcoma, although its phagocytic character was present (1). Gc-4 SD had been maintained in RPMI 1640 medium supplemented with 5% fetal bovine serum until November 1987. Protein-free culture was used intermittently for 3 months. In January 1988, re-cloning was performed in RPMI 1640 supplemented with 5% fetal bovine serum and the line which grew exponentially in protein-free medium designated as GM-40, which are RPMI 1640 medium supplemented with 10 mM of L-glutamine, 100 mg/l of sodium pyruvate, 10 mM of Hepes buffer, and 2.0 g/l of NaHCO3 (13), was selected. This was the sub-clone Gc-4 PF. Figure 1 shows in vitro growth of Gc-4 SD and Gc-4 PF in GM-40 and in GM-40 supplemented with 5% fetal bovine serum. The two clones showed parallel growth rates in the medium with 5% serum. However, in protein-free medium (GM-40), Gc-4 SD did not grow at all, while Gc-4 PF grew exponentially. The doubling time of Gc-4 PF did not change in protein-free

Remodeling of large bone defects in the treatment of space-occupying lesions

SummaryCurettage without bone graft was performed in 17 patients with benign bone tumors and tumor-like lesions. New bone formation with uniformly increased radio-density appeared in serial plain radiographs within 3 months after the operation. The average period before full weight could be borne on the lower extremities was 14 weeks. Computed tomography revealed that the central part of the bone lesions persisted without bone formation. The thickening of cortical bone was predominant. These data indicate that enough mechanical strength for daily activity will be recovered by bone within 4 months after curettage without any filler, although remodeling continues for over a year. It is suggested that bone graft and implantation of “biomaterials” are not necessary in patients, especially younger ones, with benign bone tumors or tumorous conditions.