Osteoblastoma: experience with 23 patients.

A retrospective review of 23 patients with osteoblastoma was undertaken in an attempt to answer questions concerning the aggressiveness and potential malignancy of this tumour. Demographic information confirmed that recorded in the literature. There was no suggestion of malignant potential, but, significantly, one tumour persisted, with local recurrence after 11 operations over a period of 27 years. A second tumour, a spinal lesion, occurred (still in a benign form) after a symptom-free period of 17 years. Recognition of aggressive features clinically, radiologically and histologically suggests the need for more aggressive surgical treatment, and late recurrence indicates the need for a more guarded prognosis and longer follow-up.

Massive intrapelvic synovial cyst as a complication of total hip replacement arthroplasty: a case report.

The authors report a case of massive intrapelvic synovial cyst complicating total hip arthroplasty in a 35-year-old woman with rheumatoid arthritis. The clinical presentation raised the possibility of a coincidental soft-tissue malignant tumour. This was ruled out by ultrasonography, computed tomography, fine-needle aspiration with examination of cells and culture and, ultimately, by image intensification in the operating room during aspiration of the cyst and injection of the adjacent hip joint with Hypaque. The authors conclude that perforation of the acetabular floor at total hip arthroplasty was likely the precipitating event. After 1 year there was no indication for surgical excision of the cyst.

Aggressive osteoblastoma. A case previously reported as a recurrent osteoid osteoma.

We review the case of a 58-year-old man with a benign osteoblastic lesion. This originated in the base of the right second metacarpal and eventually involved several adjacent bones, persisting for at least 27 years despite 11 operations. It was originally reported in the literature as a recurrent osteoid osteoma, but we believe it is more properly diagnosed as an aggressive osteoblastoma, since the histological pattern did not change over the years. The lesion has remained locally aggressive with no evidence of malignant characteristics.

Eosinophilic granuloma of bone.

This is a review of 48 patients registered in the University of British Columbia Bone Tumour Registry as having eosinophilic granuloma, with emphasis on the historical development, treatment and results. Comments on the place of scintigraphic imaging are included. Eosinophilic granuloma in its solitary form is a self-limiting disease requiring no treatment. It can, however, progress to multifocal disease or the historically important triad known as Hand-Schüller-Christian syndrome. There is some evidence that it may have an immunologic basis, but the authors have little new to offer with respect to its etiology.

Osteoblastoma in the very young: report of two cases.

Two cases of tumors caused by osteoblastoma in children less than 3 years old are presented. This report points out that although most osteoblastomas appear in patients less than 30 years old, it is uncommon for the lesion to present in the very young. The authors note that osteoblastoma should be considered in the differential diagnosis of a lytic lesion because patients may be too young to communicate their complaints.

Aneurysmal bone cyst: a review of 26 cases.

Twenty-six cases of aneurysmal bone cyst are reviewed to determine the frequency, preferred treatment and prognosis. Some observations are made as to the existence of aneurysmal bone cyst as a primary entity or a secondary manifestation of a more serious underlying condition. The difficulty of differentiating an aneurysmal bone cyst from a giant cell tumor of bone is acknowledged and certain similarities to unicameral bone cyst are noted, with reference to some intriguing hypotheses put forward in the literature.

Preoperative administration of high-dose methotrexate for osteosarcoma.

Nine patients, aged 9 to 27 years (median 16 years), with osteosarcoma were given high-dose methotrexate followed by folinic acid rescue before amputation. The dose of methotrexate was 12 g/m2 for children under 12 years of age and 8 g/m2 for those over 12 years. Amputation was done after two to five (median four) courses of the drug. Between 5% and 60% of tumour cells were nonviable on histologic examination. No renal or hematologic toxicity was encountered. Mild mucositis and abnormal liver chemistry were present, usually after the third dose of methotrexate. Patients who achieved higher serum methotrexate levels at 24 hours after administration also had greater tumour necrosis. Postoperatively, chemotherapy was changed to cis-platinum, doxorubicin, cyclophosphamide, actinomycin and bleomycin. Seven patients finished their medication 17 to 35 months after diagnosis. One patient died after refusing chemotherapy postoperatively and another is alive with pulmonary metastases. Preoperative chemotherapy is a novel approach to the treatment of osteosarcoma and further modification of the treatment protocol may improve results.

Giant cell tumour of bone: its aggressiveness and potential for malignant change.

Thirty cases of giant cell tumour of bone are reviewed. The average follow-up for 22 cases was 7.5 years. The recurrence rate in 19 appendicular tumours treated by curettage, with or without bone grafting, was 52%. Treatment of recurrences, however, resulted in cure of an additional 10 tumours, for an overall success rate of primary and secondary treatment of 89%. Pulmonary metastases occurred in two patients (6.7%) and there was one death attributable to the tumour (3.3%). The authors conclude that the conservative primary treatment is justified even with a 52% recurrence rate, since normal function and appearance are preserved and, further, more aggressive treatment of the recurrent tumour can be performed. They prefer limb-saving resection and occasionally amputation for this more aggressive secondary treatment rather than cryosurgery with its complications, allograft replacement with its uncertainties or supervoltage radiation with its risk of later development of malignant tumours.

Unicameral bone cyst.

A 28-year experience with 76 unicameral bone cysts is reviewed and compared to other large series and recommended treatments recorded in the English literature. Particular attention is paid to the importance of recurrence in relation to the need for secondary operations and in contrast to the disability caused by enforced restriction of activity. Evidence is presented suggesting that, in spite of residual radiologic changes, the disability is frequently insufficient to warrant a second operation. Most unicameral bone cysts probably run their own course, not always greatly affected by treatment, with very satisfactory end results.

Squamous cell carcinoma arising in chronic osteomyelitis.

Analysis of three cases and a review of the recent literature on squamous cell carcinoma arising in osteomyelitis confirm that this is an uncommon condition which may run a less benign course than was earlier believed. The disease affects chiefly middle-aged and older men, usually involves the lower extremity and most often occurs in the tibia. Development of a malignant tumour is heralded by increased pain and foul-smelling drainage in the presence of a fungating ulcer. Increased bone destruction is seen on the roentgenograms. A consistent finding is the long duration of infection but the authors stress that sinus drainage of long duration is not essential: the carcinoma can arise in scar overlying quiescent osteomyelitis as is occasionally seen in burn scars. Amputation is the treatment of choice.

The unstable shoulder: recurring subluxation.

A review of operative repairs for recurring dislocation of the shoulder revealed that a significant proportion of these operations was being done for what could best be described as recurring subluxation of the shoulder. The presenting complaint was of the shoulder 'going out of joint', but no significant trauma was recalled, dislocation was never shown on the radiograph and none required manual reduction. The only physical finding was apprehension on external rotation of the shoulder in abduction. Radiographs were frequently normal and arthrography and cineradiography were not helpful in confirming anterior displacement. The most useful preoperative information was obtained by manipulation of the shoulder under general anaesthesia just before the surgical repair. In all instances anterior instability could be demonstrated. Of 99 Magnuson-Stack repairs drawn from the records of the Vancouver General Hospital in a 3-year period, 34 proved to be examples of recurring subluxation. This high proportion of such patients contradicts the teaching in standard orthopaedic textbooks, but substantiates the warning of Rowe (1963) to beware of the patient whose shoulder 'dislocates' initially with little evidence of injury. It also substantiates Saha's concept (1971) of inherent shoulder instability as a contributor to the incidence of recurring dislocation.

Osteoid osteoma and osteoblastoma: reclassification of 43 cases using Schajowicz's classification.

Forty-three cases of benign osteoblastic tumour of bone from the University of British Columbia bone tumour registry have been reviewed and reclassified according to the classification of Schajowicz and Lemos. Their classification has the advantage that the relationship of the two lesions is recognized and overlap, both radiologically and microscopically, is allowed for. The terminology used in the new classification, however, is cumbersome and confusing and appears to be of no great advantage. We therefore recommend instead the terminology modified from that of Dias and Frost, which incorporates the observations put forth by Schajowicz and Lemos: (a) cortical osteoblastoma, (b) medullary osteoblastoma, (c) periosteal osteoblastoma and (d) multifocal osteoblastoma.