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Pigmented villonodular synovitis (PVNS) of the knee joint remains a difficult and elusive entity to define and characterize. This entity most often appears in the young adult knee with nonspecific clinical features, including a painful range of motion and perhaps a sensation of locking. Detection and diagnosis of this localized soft-tissue mass are difficult because plain roentgenograms may be totally within normal limits. The case of a 21-year-old woman illustrates the use of magnetic resonance imaging (MRI) as an effective technique to define and characterize PVNS. Advantages of MRI include high-resolution/high-contrast multiplanar sections that depict bone, marrow, ligaments and tendons, fat, menisci, and articular cartilage in one image. In addition, MRI is noninvasive and requires no ionized radiation. MRI is an excellent clinical tool for the evaluation of intraarticular tumors of the knee joint.

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A group of experts met to discuss a case from the University of California, Los Angeles, School of Medicine.

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A case of giant cell tumor (GCT) of the distal femur in a 56-year-old man is reported in association with Paget's disease. The case is unique in that is is the first report of GCT arising in a patient with this disease in which the neoplasm arose in a bone that did not show radiologic evidence of Paget's disease. This case also represents the first example of such an association in which viral-like inclusion bodies are seen in the osteoclast of the tumor. The fact that similar inclusion bodies are seen in the osteoclast of patients with Paget's disease and in their GCT implies a cause-and-effect etiologic relationship rather than mere coincidence. The implications are that a slow-virus infection is involved in the pathogenesis of Paget's disease and in giant cell tumors occurring in patients with this disease.

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Post-meniscectomy knees examined with an instrumented clinical testing device reveal that meniscectomy alone does not cause a measurable degree of instability. If meniscectomy causes a minor degree of instability, the degree is within the right-left variation for a normal population. Medical meniscectomy in combination with a torn anterior cruciate results in an increased anterior-posterior instability at 20 degrees knee flexion. The device used in this study was more reliable in diagnosing increased anterior-posterior instability secondary to anterior-cruciate tear than was a clinical examiner.

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The rationale for amputation for local tumor control of skeletal and soft tissue sarcomas was based on results obtained from surgical therapy alone. However, our previous results from a pilot trial of multimodality therapy of preoperative chemotherapy and radiation therapy followed by surgical resection indicated that limb salvage (without amputation) could be accomplished in most patients with little morbidity and low recurrence rate. This report summarizes our experience in a prospective trial from January 1972 to December 1979. A total of 105 consecutive patients with soft tissue sarcomas (65 patients) or bone sarcomas (40 patients) were treated with preoperative intraarterial adriamycin, 3500 rads of rapid-fraction radiation and radical en bloc resection of primary tumor. Diseased bones were replaced with cadaver allografts (22 patients), metallic endoprostheses (10 patients) autologous bone (2 patients), or no replacement (ilium or fibula-4 patients). Salvage of a viable, neurologically intact, functional extremity was achieved in 98/105 patients (98%); 97% of limb salvage patients were free of local recurrence after a median follow-up period of 28 months. Major complication rate that required amputation was 3/105 patients (2%). Postoperative adjuvant chemotherapy with cyclical adriamycin and high-dose methotrexate was employed for all patients with osteosarcoma and 35 patients with grade III soft tissue sarcomas. The overall disease-free rate is 50% (18/35) for osteosarcomas and 65% (42/65) for soft tissue sarcomas. These results indicate that local tumor control can be achieved in 91% of patients without amputation. Their functional capabilities are excellent with a low complication rate. Since the advent of adriamycin and methotrexate has significantly improved the overall survival for patients with skeletal and soft tissue sarcomas, the quality of this survival has become even more important. Preoperative multimodality therapy is a major advance in this direction and since results of limb salvage procedures appear to be equal or superior to those achieved by amputation we believe these alternatives should be offered to all patients.

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UNLABELLED: Specimens of twelve osteosarcomas, five chondrosarcomas, one giant-cell tumor, and five extraskeletal soft-tissue sarcomas were transplanted into male athymic nude (nu/nu) mice. Survival of the transplant was determined by the volume-doubling time and the sex chromatin of the tumor cells obtained from two female patients. By these criteria and the similarity of the histological composition of the original tumor and the transplant, survival occurred in four of twelve osteosarcomas and four of five chondrosarcomas. Without any local infiltration of lymphocytes or plasma cells, or other evidence of cell-mediated immunity, the surviving tumors regressed by the fourth week after the operation. Transformed osteoblasts and osteoprogenitor cells were replaced by fibrous connective tissue or fibrogenic tumor-tissue cells. Osteocytes degenerated and disappeared from the lacunae. The one giant-cell tumor transplant survived, growing very slowly, but by the end of the first week after transplantation whorls of mononucleated cells appeared in sites previously occupied by multinucleated cells. Transplants of leiomyosarcoma, liposarcoma, and synovioma (one tumor of each) degenerated. One of two fibrosarcomas survived transplantation. The most striking reaction of the mouse host bed was to encompass six of twelve osteosarcomas and four of five chondrosarcomas in deposits of normal living cartilage, bone, and bone marrow. The incidence of new bone inducedy by living transplants was only slightly greater than by implants of freeze-dried killed osteosarcoma tissue. Not one of five extraskeletal sarcomas, living or dead, induced bone formation. These observations suggest that an osteoinductive agent is transmitted by some osteosarcomas and chondrosarcomas. This agent initiates differentiation of host mesenchymal cells into normal non-tumorous cartilage and bone, which later colonized by bone marrow. CLINICAL RELEVANCE: Our observations present experimental evidence of the origin of the envelope of normal non-tumorous bone that may surround tumorous bone. In 1926, Phemister recognized the clinical significane of this envelope as a pitfall in the differential diagnosis of malignant bone tumors, chondrosarcoma, myositis ossificans circumscripta, and other neoplasms. He emphasized the importance of examining the entire specimen for the distribution of deposits of tumorous and normal bone. The induction of normal bone formation in the host bed surrounding transplants of osteosarcomas and some chondrosarcomas (but not transplants of fibrosarcoma, liposarcoma, or leiomyosarcoma) is evidence of a specific tumor-cell characteristic. Thus, the bone inductive response is not an unspecific reaction to injury from expansion or of tumor growth but a biological response to tumor-cell products. Transplants of human malignant tumors growing in the thymus-deficient mouse can be treated by combinations of radiation, amputation, and new chemotherapeutic agents...

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Double-contrast shoulder arthrography was used to define the normal and abnormal arthrographic anatomy of the glenoid labrum. A retrospective study of 12 patients suspected of having labral abnormalities or who had unexplained shoulder disability consistent with capsular laxity was undertaken. In four of the nine patients with abnormal arthrograms, the study revealed critical anatomic alterations not detectable on physical examination or pain radiographs.

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An osteoid osteoma, excised from the neck of the femur of a 23-year-old man, was cut into four 1.5 mm3 fragments and immediately transplanted into muscle pouches in athymic nude mice. One fragment was devitalized by lyophilization before implantation. The viable tumor cell xenografts grew, differentiated into uncalcified osteoid, and retained the characteristics of the original tumor. The killed implants were resorbed, but both the surviving viable and nonviable tumor tissue induced the connective tissue cells of the mouse host bed to proliferate and differentiate into normal cartilage and calcified bone. The mouse new bone deposits were remodeled and colonized by bone marrow, a tissue not seen in osteoid osteomas. These observations suggest that the sclerotic bone shell characteristic of osteoid osteomas may be an inductive reaction of host bed tissue to an osteoma cell product that is comparable to bone morphogenetic protein (BMP) produced by normal bone cells and transferred by normal bone matrix.

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Our results indicate that it is technically possible to resect the hemipelvis and maintain a viable extremity. Functional results are remarkably good and tumor control has been equivalent to standard hemipelvectomy. Excision of the ilium with preservation of the extremity in selected cases would appear to be a reasonable alternative to the standard hemipelvectomy, which involves amputation of the extremity.

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Metastases from genitourinary tumors frequently involve the skeletal system and often produce the most disabling symptoms. Judicious early orthopedic management may prevent paralysis and maintain ambulation, thus significantly improving the quality of life. The role of prophylactic surgery for impending fractures and the symptomatic therapy of painful metastatic foci are discussed.

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Anterior and posterior marginal fracture dislocations of the distal radius are unusual injuries, both of which are called Barton's fracture in the current world literature. Barton's original description delineates only the posterior marginal injury. An attempt is made to clarify the nature of these injuries by a complete review of the literature and a study of the clinical experience at UCLA Hospital from 1972 through 1975. Ten anterior and five posterior marginal fractures were treated during that period of time, constituting 2.3 per cent of all distal forearm fractures. Fractures in males typically stemmed from high velocity accidents in the younger age group and were associated with significant additional injuries. The injuries in females resulted from simple falls, generally in the older age group. Eight fractures were treated open and seven closed without complications; treatment results have not been determined yet. Eponym descriptions should be discontinued and replaced with a lucid anatomically descriptive classification such as anterior and posterior marginal fracture-dislocations of the distal radius.

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Multimodality management of extremity skeletal and soft tissue sarcomas with preoperative intra-arterial Adriamycin and radiation therapy, radical surgical resection and postoperative chemotherapy or chemo-immunotherapy has resulted in preservation of a functional extremity in 13 or 14 patients. Seven of 8 patients with Stage IIIA and IIIB soft tissue sarcomas, managed with preoperative intra-arterial Adriamycin and radiation therapy, followed by en bloc soft tissue resection and 6 patients with bone sarcomas managed by preoperative treatment, followed by bone resection and replacement with cadaver bone allografts, remained free of disease from 4 to 34 months. The results of the combined modality approach were significantly better than the results obtained in patients managed by surgical resection alone, or by combination of operation with another single modality, both in terms of short term-recurrence free survival and salvage of a functional extremity.

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As seen by the graphic depiction of F.M.'s sagittal diameter (Fig. 3) and by the photographs of his air myelogram, cervical sagittal stenosis should be looked for and thought of as an underlying anatomic anomaly in the athlete who has recurrent episodes of "pinched nerve" with flexion and hyperextension of his cervical spine during blocking or tackling. It is significant that the patient underwent two "normal" cervical spine x-rays before tomograms and air myelogram pointed out the sagittal stenosis of his cervical canal. Sagittal stenosis must be thought of and looked for strenously in the athlete competing in high velocity collision sports where recurrent neck and upper extremity complaints are too often attributed to the pinched nerve complex and a "horseshoe" collar is the remedy.

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