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Biomedical subjects

H J Mankin

Publications and source records attributed to H J Mankin.

At least 37 records · Page 2Linked to original sources
PubMed2000

Orthopaedics, ethics, and industry. Appropriateness of gifts, grants, and awards.

At the Academic Orthopaedic Society meeting in San Francisco on November 8 and 9, 1996, the membership addressed the issue of ethics and industry in an academic setting. Using a Delphi panel technique, they arrived at a definition of conflict of interest, and 41 separate points of acceptable and unacceptable behavior related to gifts, research awards, and funding of various activities. The Academic Orthopaedic Society Delphi Committee also mailed 191 questionnaires (157 department chairpersons and 34 program directors) to 157 training programs. The respective department chairpersons and program directors were asked to copy and distribute the questionnaires to staff (faculty) and house officers (residents and fellows) to complete anonymously and return them for collation. Ninety-one programs (58%) responded. Three hundred and fifty-two questionnaires were returned (237 from staff, 115 from house officers), each of which expressed agreement or lack of agreement with the Delphi panel report using a Likert scale technique. With only modest (and usually predictable) disagreement on certain items, the final statements by the Delphi panel were supported strongly by the survive results. The Academic Orthopaedic Society believes that the major points arrived at by the panelists should serve as the basis for ethical guidelines in the relation between academic orthopaedic institutions and industry.

Awards and Prizes↗
PubMed2000

Synovial joint degeneration and the syndrome of osteoarthritis.

The adverse effects of osteoarthritis on the quality of life for tens of millions of people and on the costs of health care and economic productivity make it a major health problem that will increase in incidence and impact with the aging of the population. Although in most patients the cause of osteoarthritis remains unknown and no cure has been identified, appropriate diagnosis and treatment, including education of the patients, can minimize symptoms and help patients maintain active and productive lives. Accomplishing this aim requires that physicians have an understanding of the pathophysiology of joint degeneration and the relationships between joint degeneration and the clinical syndrome of osteoarthritis. Although much remains to be learned about the development and progression of the joint degeneration responsible for osteoarthritis, it is clear that the loss of articular cartilage results from disruption of the structural integrity of the articular cartilage coupled with or caused by an imbalance in the anabolic and catabolic activity of the tissue. The progression of joint degeneration varies considerably among patients. In some individuals the joint degenerates rapidly; in others the degenerative changes progress slowly over decades and in others the disease may remain stable. In rare patients, the joint degenerative changes spontaneously improve. Although joint degeneration is the underlying cause of the symptoms of osteoarthritis, including joint pain and loss of joint function, not all patients with joint degeneration have symptoms of osteoarthritis. Future therapeutic approaches may include disease-modifying drugs and surgical procedures that correct mechanical abnormalities, debride joints, and replace degenerated articular cartilage with implants that stimulate restoration of a cartilaginous joint surface. Development of methods to detect and monitor subtle changes in cartilage metabolism and identify the joint changes that precede loss of articular cartilage may make it possible to detect the earliest signs of osteoarthritis, when therapeutic interventions have the greatest potential for preventing progression of the disease.

Humans↗
PubMed2000

Chondroblastoma of bone.

BACKGROUND: Chondroblastoma of bone is a rare lesion, and few large series have been reported. The purpose of this paper is to report forty-seven cases treated by one group of surgeons and to identify factors associated with more aggressive tumor behavior. METHODS: Seventy-three patients with chondroblastoma of bone were treated between 1977 and 1998. We were able to obtain historical data, imaging studies, histological findings, and adequate personal or telephone follow-up to determine the outcome for forty-seven patients. RESULTS: The lesions were distributed widely in the skeleton, but most were in the epiphyses or apophyses of the long bones, especially the proximal part of the tibia (eleven tumors) and the proximal part of the humerus (ten tumors). The principal presenting symptoms were pain and limitation of movement. The treatment consisted of a variety of procedures, but the majority of the patients had intralesional curettage and packing with allograft or autograft bone chips or polymethylmethacrylate. Most of the patients had an excellent functional result, although in three osteoarthritis developed in the adjacent joint. Seven patients (15 percent) had a local recurrence; three of them had a second recurrence and one, a third recurrence. One patient died of widespread metastases, and another who had metastases to multiple sites was alive and disease-free after aggressive treatment of the metastatic lesions. CONCLUSIONS: While the size of the lesion, the age and gender of the patient, the status of the growth plate, and an aneurysmal-bone-cyst component to the tumor had no significant effect on the recurrence rate, lesions around the hip (the proximal part of the femur, the greater trochanter, and the pelvis) accounted for the majority (five) of the seven recurrent tumors and one of the two metastatic lesions.

Adolescent↗
PubMed1999

Magnetic resonance imaging features of allografts.

OBJECTIVE: To investigate the magnetic resonance imaging (MRI) features of allografts at various time intervals after surgery in patients with osteoarticular allografts. DESIGN AND PATIENTS: Sixteen patients who were treated with osteoarticular allografts and who were followed over time with MRI studies as part of their long-term follow-up were retrospectively selected for this study. T1-weighted images were obtained both before and after gadolinium administration along with T2-weighted images. All images were reviewed by an experienced musculoskeletal radiologist, with two other experienced radiologists used for consultation. Imaging studies were organized into three groups for ease of discussion: early postoperative period (2 days to 2 months), intermediate postoperative period (3 months to 2 years), and late postoperative period (greater than 2 years). RESULTS: In the early postoperative period, no gadolinium enhancement of the allograft was visible in any of the MR images. A linear, thin layer of periosteal and endosteal tissue enhancement along the margin of the allograft was visible in images obtained at 3-4 months. This enhancement appeared gradually to increase in images from later periods, and appears to have stabilized in the images obtained approximately 2-3 years after allograft placement. The endosteal enhancement diminished after several years, with examinations conducted between 6 and 8 years following surgery showing minimal endosteal enhancement. However, focal enhancement was noted adjacent to areas of pressure erosion or degenerative cysts. All the cases showed inhomogeneity in the marrow signal (scattered low signal foci on T1 with corresponding bright signal on T2), and a diffuse, inhomogeneous marrow enhancement later on. CONCLUSION: We have characterized the basic MRI features of osteoarticular allografts in 16 patients who underwent imaging studies at various time points as part of routine follow-up. We believe that the endosteal and periosteal enhancement observed on MRI during the first few months to 2 years following surgery represents vascular ingrowth and early skeletal repair. The zone of periosteal enhancement could also include the new bone laid on the surface of the allograft through which the soft tissues bind to the cortex. The exact reason for the inhomogeneity in the marrow signal, and the diffuse, inhomogeneous marrow enhancement is not clear. This may represent saponified and/or necrotic marrow fat interspersed with the fibrovascular tissue. The features noted here should provide radiologists with useful information regarding imaging characteristics they can expect to see in other allograft replacement patients.

Adolescent↗
PubMed1999

Bone banking. Update on methods and materials.

Bone allografts are being used in increasing numbers by orthopedic surgeons, yet many surgeons are unfamiliar with their preparation and processing, as well as their use as safe and effective transplants. This article reviews current sources of bone allografts, new methods of processing to achieve optimal results, the biology of incorporation of allografts, and new bone substitutes.

Biology↗
PubMed1999

Long-term follow-up of patients with osteochondral allografts. A correlation between immunologic responses and clinical outcome.

This article confirms immunologic responses in humans to histocompatibility antigens (Class I and II) presented by frozen osteochondral allografts. These observations include a correlation of immune responses with long-term clinical outcome. As found in animal models, matching of histocompatibility antigens, particularly to Class II, improves clinical and, presumably, biologic success following implantation of massive frozen bone allografts in humans. The presence of sensitization clearly does not preclude a satisfactory outcome, nor have other reconstructive alternatives (e.g., metallic implants) been shown to be superior in their long-term results.

Animals↗
PubMed1999

Tumor reconstruction.

This article discusses opinions for reconstruction of bony defects created by tumor resections. The literature is reviewed, and the results of different reconstruction methods from the Massachusetts General and Children's Hospitals' database are discussed. The authors' treatment goals and algorithms are reviewed as well as the rationale behind them.

Algorithms↗
PubMed1999

Infiltrative subcutaneous malignant fibrous histiocytoma: a comparative study with deep malignant fibrous histiocytoma and an observation of biologic behavior.

Malignant fibrous histiocytoma (MFH) is one of the most common soft tissue sarcomas of adulthood. Although it is usually intramuscular and pseudocapsulated, we have recently observed MFHs with extremely infiltrative growth margins, which are predominantly located in the subcutis. These lesions are often associated with incomplete primary surgical excision, the subsequent need for additional surgery or adjuvant therapy, and an increased risk for local recurrence. To further analyze the growth pattern and clinical implication of the subcutaneous infiltrative MFHs, we reviewed a series of 24 subcutis and 21 intramuscular MFHs of the extremities. Morphologically, we defined "infiltrative" as tumor extension along normal tissue planes for a minimum measurable distance of 2 mm from the edge of the main mass. Radiographic findings were correlated with pathologic findings. Of the 24 subcutis MFHs, 83% showed an infiltrative growth pattern, involving 5% to 90% (mean, 51%) of the evaluable margin. Fifty percent of patients with subcutaneous MFH had both an infiltrative growth pattern and positive surgical resection margin on initial resection. Only 25% noninfiltrative subcutaneous MFHs had a positive initial surgical resection margin. Of the 21 intramuscular MFHs, only 5 (24%) had an infiltrative growth pattern that involved 5% to 90% (mean, 40%) of the evaluable margin. One of the five tumors had 90% margin infiltration with multiple positive surgical resection margins. Of 16 noninfiltrative intramuscular MFHs, 3 (19%) had positive resection margins. Magnetic resonance imaging (MRI) and/or computed tomography (CT) scan correctly identified the growth pattern in 87% of subcutaneous and 88% of intramuscular MFHs. Patient follow-up evaluation showed that four (17%) patients with subcutaneous MFHs had resection-proven recurrences, 6 to 57 months after diagnosis. All four of these tumors had infiltrative growth patterns and positive margins on the original surgical resection. There were no local recurrences of the intramuscular MFHs. Two patients of 20 in the infiltrative subcutaneous MFH group and two patients of four in the well-circumscribed subcutaneous MFH group had biopsy-proven metastases, which developed within 5 years after diagnosis. Six patients had metastases in the intramuscular MFH group. A group of MFHs, predominantly subcutaneous, have an extremely infiltrative growth pattern. This growth pattern, documented by radiographic methods and/or light microscopic examination of biopsy specimens, should indicate that a wider margin on initial resection is necessary to entirely excise the lesion. The presence or absence of an infiltrative growth pattern is not predictive of the tumor's metastatic potential.

Adult↗
PubMed1999

Decreasing length of hospital stay in treatment of osteoid osteoma.

Ninety-eight operative procedures were performed for treatment of osteoid osteoma since 1978 at the authors' institution. During these years there was a progressive decrease in the length of hospital stay, decreasing from a mean of 6.8 days between 1978 and 1980 to 2.6 days between 1994 and 1996. Factors that influenced the length of stay after a surgical procedure include patient age, lesion location, choice of procedure, and surgeon. However, the decline in length of stay with time is independent of these factors, and antedates the era of managed care. Increased reliance on more conservative surgical procedures has markedly diminished the length of hospital stay required in the care of these patients.

Adolescent↗
PubMed1999

Chondrosarcoma of bone: an assessment of outcome.

BACKGROUND: The data on 227 patients who had been managed for a chondrosarcoma at one institution were reviewed to determine the nature of the lesions, the predictors of outcome, and whether there were any ways to change the treatment approaches to improve the results. METHODS: The patients were followed for a mean duration of six years (range, three to twenty-five years). The mean age of the patients was forty-seven years (range, nine to eighty-four years). The most prevalent sites of the tumors were the femur (seventy-eight), the pelvis (fifty-one), and the humerus (thirty-nine). The tumors were divided into two groups according to histological grade. Eighty-six tumors (sixteen atypical enchondromas and seventy grade-1 chondrosarcomas) that were locally destructive but were associated with a low likelihood of metastasis were considered to be low-grade. The remaining 141 lesions, which were locally destructive, potentially metastatic, and capable of causing death, were thought to be high-grade. One hundred and three of these 141 lesions were grade 2, and thirty-eight were grade 3 (eighteen of the thirty-eight were grade 3 only, and twenty were both grade 3 and dedifferentiated). Two hundred and twenty-four patients were managed with resection and a limb-sparing procedure; the remaining three patients had an amputation. Postoperative adjuvant radiation was used for fifty-six patients; chemotherapy, for thirty-five; and both radiation and chemotherapy, for nineteen. Flow cytometric patterns were analyzed for 105 patients. RESULTS: The patients who had a high-grade tumor were older than those who had a low-grade tumor (mean age [and standard deviation], 50+/-17.0 years compared with 40+/-15.9 years; p < 0.001). Pathological fracture, metastasis, local recurrence, and death were more prevalent in the group that had a high-grade lesion (p < 0.001). Predictors of metastasis and death in that group of patients included local recurrence, a pelvic location of the tumor, a tumor that was more than 100 cubic centimeters in size, a ploidic abnormality (aneuploidy coupled with a high mean DNA index), a histological grade of 3, and a dedifferentiated type of tumor (p < 0.001). CONCLUSIONS: Although the data are suggestive, with the numbers available for study we could not detect a significant difference in the rates of pulmonary metastasis and death between the patients who had a grade-3 lesion and those who had a grade-3 lesion that was also dedifferentiated. However, the interval between diagnosis and death was 32+/-22.8 months for the patients who had a grade-3 lesion compared with 5+/-3.7 months for those who had a grade-3 lesion that was also dedifferentiated (p < 0.001). Overall, patients who had had a resection with wide margins (margins extending outside the reactive zone) had a longer duration of survival than did those who had had a so-called marginal resection (margins extending outside the tumor but within the reactive zone) or an intralesional resection (margins within the lesion) (p < 0.04). Adjunctive chemotherapy or radiation, or both (which, it must be noted, was used, without a protocol, in a relatively small number of patients), after an intralesional resection, for recurrent disease, or for distant metastasis did not appear to alter the outcome.

Adolescent↗
PubMed1999

Megavoltage radiation therapy for axial and inoperable giant-cell tumor of bone.

BACKGROUND: Treatment of giant-cell tumor of bone generally involves wide en bloc resection of the lesion and the surrounding bone or curettage with or without bone-grafting or the use of cement. Radiation therapy has been used for patients who cannot be operated on for medical reasons or who have a tumor that is technically difficult to resect or that cannot be resected because of its location. We performed the present study to evaluate the efficacy of megavoltage radiation in terms of lack of tumor progression and treatment-related morbidity. METHODS: Twenty patients who had giant-cell tumor of bone were managed with a single course of megavoltage radiation (forty to seventy gray administered at 1.8 to 2.0 gray per fraction with an average total duration of treatment of five to seven weeks) between March 1973 and March 1992. We used megavoltage photons, 160-megaelectron-volt proton beams, or a combination of the two. RESULTS: After a median duration of follow-up of 9.3 years, the tumor had not progressed in seventeen of the twenty patients. Thus, the actuarial ten-year rate for lack of progression was 85 percent. Local regrowth was evident in one patient who had received radiation alone and in two of the thirteen patients who had been managed with partial resection and radiation. Operative treatment was successful in the three patients in whom the radiation treatment had failed. No radiation-induced tumors were observed in our series. CONCLUSIONS: We concluded that giant-cell tumor of bone was effectively treated with megavoltage radiation in our series of twenty patients in whom operative resection would have been difficult or was not feasible. The rate of tumors that did not progress with this regimen of radiation is similar to that reported by investigators from several other centers. Furthermore, these results closely rival those obtained with modern curettage procedures. Malignant sarcomatous transformation was not observed in our series. A longer duration of follow-up of a larger group of patients is necessary to provide a better estimate of the risk of malignant transformation.

Actuarial Analysis↗
PubMed1999

Diversity in orthopaedics.

There is little doubt that women, African Americans, and Hispanics, have fewer opportunities to enter, or once in, to become contributing members of orthopaedic programs in the United States. The expressed reasons for this by faculty members sometimes sound reasonable, but on analysis all are spurious. It is the responsibility of the chief of service and the faculty members to change this pattern and offer all individuals equal opportunity and treat them identically to anyone in the program or on the faculty. Some guidelines are provided.

Black or African American↗
PubMed1999

Risk factors for osteonecrosis in patients with type 1 Gaucher's disease.

This study investigated 51 patients with Type 1 Gaucher's disease clinically and radiographically for the presence of osteonecrosis. Twenty-five female and 26 male patients with a mean age of 37 years were evaluated retrospectively for osteonecrosis of the proximal and distal femur, proximal tibia, and proximal humerus. All patients were examined before enzyme replacement therapy. Gender, age at diagnosis, prior splenectomy, hematocrit, platelet count, acid phosphatase level, radiographs of the long bones, and magnetic resonance quantitative chemical shift imaging of the spine were analyzed to see if any of these values or findings were associated with the presence of osteonecrosis. Splenectomy was an independent risk factor for the presence of osteonecrosis in three of the four major sites and was a multivariate risk factor for osteonecrosis of the proximal femur and tibia. Male gender was the other significant multivariate risk factor for osteonecrosis of the humerus and distal femur when all sites were taken into account.

Acid Phosphatase↗
PubMed1999

A managed care world. Can academic activities survive?

As a guest speaker at the Brown University Medical School Graduation, the author described some aspects of managed care that impact on academics and more specifically teaching and research. The issues for education included the reduction in numbers of residents and fellows; the rapidity with which the patients must be treated; the reduction in monies for educational activities; and consuming and at times needless paperwork. As far as research is concerned the reduction in time and money have had a negative effect on this important aspect of academic life for physicians. Several proposals are put forth to maintain the quality of these educational and investigational pursuits, and the students soon to be residents and, hopefully, academicians are advised to maintain the highest standards and appreciation for quality care, education, and research.

Education, Medical↗