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Robert K Heck

Publications and source records attributed to Robert K Heck.

7 recordsLinked to original sources
PubMed2006

Pathological fracture in acute osteomyelitis of long bones secondary to community-acquired methicillin-resistant Staphylococcus aureus: two cases and review of the literature.

Pathologic fracture is a rare complication of acute bacterial osteomyelitis in adults. Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) has been increasingly reported in skin and soft tissue and systemic infections in children and adults, including many cases of osteomyelitis. We recently treated two adult patients with acute osteomyelitis of long bones secondary to CA-MRSA complicated by a pathologic fracture. In both patients, the primary source of dissemination to the bone was a skin and soft tissue infection. We speculate that virulence factors specific for CA-MRSA currently circulating in the United States may predispose to a complicated course of acute osteomyelitis.

Adult↗
PubMed2006

Reconstruction of noncontained distal femoral defects with polymethylmethacrylate and crossed-screw augmentation: a biomechanical study.

BACKGROUND: Curettage and cementation with polymethylmethacrylate are frequently used in the treatment of aggressive benign bone lesions such as giant-cell tumors, but strength and stiffness of the reconstructed bone have been concerns. This biomechanical study was undertaken to determine whether augmenting the cement with crossed screws would result in a stronger reconstruction. METHODS: Large noncontained defects were created in the medial femoral condyles of twenty matched pairs of human cadavera. Four groups were organized to compare three types of reconstruction: (1) polymethylmethacrylate alone, (2) polymethylmethacrylate and intramedullary Steinmann pins, and (3) polymethylmethacrylate with crossed screws engaging the opposite cortex. The specimens were subjected to 2000 compressive cycles and were subsequently monotonically loaded to failure under a controlled displacement rate. Failure load and stiffness were determined for each femur that survived the cycling process. RESULTS: Femora reconstructed with crossed screws and cement failed at higher loads and had greater stiffness than those reconstructed with cement alone (p = 0.025 and p = 0.0007) or cement augmented with intramedullary Steinmann pins (p = 0.019). Failure of femora reconstructed with cement and crossed screws occurred through an extra-articular transverse fracture, while failure in those with cement alone and cement with Steinmann pins occurred through an intra-articular (intercondylar) fracture. CONCLUSIONS: In this in vitro cadaver study, augmentation of polymethylmethacrylate cement with crossed screws resulted in a stronger reconstruction of distal femoral tumor defects than that obtained with cement alone or with cement and intramedullary Steinmann pins.

Aged↗
PubMed2004

The incidence and prognosis of osteosarcoma skip metastases.

The poor prognosis for patients with osteosarcoma skip metastases has been established in the literature; however, most of the data in the literature concerning osteosarcoma skip metastases were collected before routine use of magnetic resonance imaging and before the use of modern multiagent chemotherapy regimens. This retrospective multiinstitutional study was done to evaluate the efficacy of magnetic resonance imaging to detect skip metastases and to evaluate the prognosis for these patients when treated with modern multiagent chemotherapy protocols. In a group of 155 patients who were younger than 26 years when diagnosed and treated for high-grade osteosarcoma of the long bones, 10 (6.5%) patients with skip metastases were identified. Eight of the 10 lesions were detected on pretreatment magnetic resonance imaging scans and two were detected only from the surgical pathology specimens. Five patients had concomitant pulmonary metastases at presentation and five patients had no other known site of diseases. All 10 patients died, with an average survival of 32.5 months (range 11-71 months). The five patients with only skip metastases at presentation survived an average of 27.2 months (range 15-44 months). Despite advances in the treatment of patients with osteosarcomas, those with skip metastases continue to have a poor prognosis, and they should be counseled regarding the limitations of current therapies.

Adolescent↗
PubMed2003

A comparison study of staging systems for bone sarcomas.

A retrospective study of 250 patients treated at one institution was done to evaluate the prognostic significance of the new American Joint Committee on Cancer staging system compared with the Musculoskeletal Tumor Society staging system for patients with sarcomas of bone. Regarding the Musculoskeletal Tumor Society system, there were significant differences in survival among patients with Stage I, Stage II, and Stage III disease. There were no significant differences between patients with Stages I-A and I-B disease, nor between patients with Stages II-A and II-B disease. Similarly, regarding the new American Joint Committee on Cancer staging system, there were significant differences among patients with Stage I, Stage II, and Stage IV disease. No significant differences were seen between patients with Stages I-A and I-B disease, between patients with Stages II-A and II-B disease, nor between patients with Stages IV-A and IV-B disease. A significant advantage in the ability to predict prognosis for one staging system over the other staging system was not shown with the relatively small number of patients in this study.

Ameloblastoma↗
PubMedDate not supplied

Staging of primary malignancies of bone.

Staging of bone sarcomas is the process whereby patients are evaluated with regard to histology, as well as the local and distant extent, of disease. Bone sarcomas are staged based on grade, size, and the presence and location of metastases. The system is designed to help stratify patients according to known risk factors. Proper staging helps define the prognosis for patients and helps guide their treatment. Furthermore, staging allows meaningful comparisons to be done among groups of patients.

Bone Neoplasms↗