The evaluation of compartmental syndromes using somatosensory evoked potentials in monkeys.

Somatosensory evoked potentials (SEPs) of the median, deep peroneal, and tibial nerves were recorded in experimentally induced compartmental syndromes in nine Macaca mulatta monkeys. A total of 17 trials were performed at the following mean pressure levels: 17, 30, 36, and 40 mm Hg. Evoked potentials were recorded using a four-channel evoked response system. Significant changes in SEP waveforms (greater than 3-millisecond increases in N1 or P1 latencies, or a 50% decrease in wave amplitudes in the presence of normal contralateral waveforms) were seen at pressures as low as 30 mm Hg as early as 45 minutes. Pressures of 35 and 40 mm Hg led to more pronounced abnormalities in SEP waveforms, with marked decreases in wave amplitudes and variability in the time to onset of these changes. Somatosensory evoked potentials are noninvasive, sensitive, and dynamic determinations of nerve function and may have clinical significance in the early detection of nerve dysfunction in compartment syndromes.

Scapular osteochondroma presenting with exostosis bursata.

A 33-year-old male presented with acute onset of scapular winging following an injury to the shoulder girdle. A scapular osteochondroma was identified radiographically that was completely asymptomatic until the time of injury. Clinical presentation included the presence of a large exostosis bursata. Surgical resection of the osteochondroma resulted in resolution of all signs and symptoms.

Gas gangrene. A review.

Gas gangrene continues to cause significant morbidity and mortality. This monograph reviews the entire spectrum of clostridial infection, including its etiology, pathophysiology, diagnosis, current recommended treatment, and prophylaxis. The early diagnosis of gas gangrene is paramount, as delay in aggressive combined treatment may result in death.

Total femur replacement. A case report with 35-year follow-up study.

In 1965, Buchman published a report of a total femur and knee joint replacement he had performed the previous year. He reported this was his second total femur replacement and made passing reference to his first such case, noting only that it had been undertaken in a desperate effort to avert a hip disarticulation. The present authors report a 35-year follow-up study of Buchman's first case, the earliest known case of a total femur and knee joint replacement.

Osteochondral allografts for limb salvage.

Use of osteochondral allografts has increased over the past 10 years in combination with improved procedures for bone procurement and storage, the development of protocols for tumor staging and diagnosis, successful adjuvant therapies that prolong survival, and greater emphasis on improved quality of life for persons with aggressive neoplasms of bone. The success rate after allograft implantation is high; there is also a high rate of complications. Comprehensive, effective nursing care is among the essential requisites for a successful, uncomplicated outcome.

Clear-cell chondrosarcoma. An unusual case complicated by a microinfiltrative pattern of bone marrow involvement and postsurgical myositis ossificans.

A case of clear-cell chondrosarcoma occurred in the proximal femur of a 32-year-old man. The tumor was complicated by a focus of myositis ossificans resulting from a previous intralesional biopsy. Histologic findings included an unusual marrow infiltration by the tumor. The patient was treated with wide resection and has no evidence of local recurrence or distant spread of disease 18 months later.

Giant cell tumor of bone with pulmonary and lymph node metastases. A case report.

A giant cell tumor of bone appeared in a lymph node of a 21-year-old man at the time of local recurrence in its original location in the distal femur, prior to metastasizing the lung. Following a wide resection, the lesion did not recur, but asymptomatic pulmonary metastases were discovered. DNA analysis by flow cytometry demonstrated identical patterns in the primary and initial recurring lesions, as well as in the pulmonary metastases, which suggests that this technique may be a valuable diagnostic tool for assessing the potential aggressiveness of giant cell tumor of bone. Giant cell tumor of bone is rarely associated with metastases of any kind. Rare instances of pulmonary spread have been reported in the literature. Lymph node involvement is even more unusual. Only two such cases have been previously reported.

Computed tomography of extraosseous ganglia.

Computed tomography (CT) was performed in six patients with painful soft-tissue masses where sarcoma was suspected. Incisional or excisional biopsy proved all to be extraosseous ganglia. CT delineated the anatomic relationships of the masses. The CT density of four of the ganglia was 18 Hounsfield Units (HU), consistent with that of fluid-filled lesions. Contrast medium did not enhance the lesions on CT. Angiography was performed in four cases and demonstrated hypovascular masses with no vessel displacement. Plain radiographs and technetium bone scintigrams were nonspecific. CT was the best preoperative confirmation of the diagnosis of benign extraosseous ganglia and the best method of localizing the lesions with respect to surrounding bone and soft tissues.

Computed tomography of parosteal osteosarcoma.

Twelve patients with parosteal osteosarcomas were evaluated by computed tomography (CT). CT accurately defined the extent of the tumors for purposes of surgical planning, although tumor bone often could not be distinguished from thickened host bone. Nine tumors invaded the medullary cavity, a feature that implies a poorer prognosis when the tumor also contains high-grade areas. Six CT studies accurately detected the medullary invasion, but three did not. Lucent areas within dense tumors contained either benign tissue or high- or low-grade tumor; CT did not differentiate among these different tissues. CT also did not reveal small satellite nodules of tumor beyond the main tumor mass.