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R D Altman

Publications and source records attributed to R D Altman.

At least 55 records · Page 3Linked to original sources
PubMed1997

Enlarged acetabular labra in the Pima Indians.

OBJECTIVE: To report the descriptive epidemiology of acetabular labral enlargement and analyze associations of other variables with this variant. METHODS: Pelvis radiographs from 761 Pima Indians aged > or = 45 years enrolled in a population based study were read by Kellgren-Lawrence global and individual radiographic features grading scales for osteoarthritis (OA) at separate settings. In total, 722 radiographs remained eligible for this study after excluding 12 unreadable radiographs and 27 cases of radiographic hip OA (Kellgren-Lawrence grade > or = 2). Enlarged acetabular labra were recorded during readings of individual radiographic features. RESULTS: Enlarged acetabular labra were present in 16% of study participants without OA and were significantly associated with female sex, but not with the variables age, body mass index, clinical hip joint involvement, diabetes, or serum insulin concentrations. CONCLUSION: Acetabular labral enlargement is common in the Pima Indians, and although not in excess of other reported acetabular margin anomalies, it differs in appearance and is not associated with age. Recognition of this structural variant is important because it can mimic fractures or osteophytes.

Acetabulum↗
PubMed1996

Preferences in the management of osteoarthritis of the hip and knee: results of a survey of community-based rheumatologists in the United States.

OBJECTIVE: To determine rheumatologists' preferences in the medical management of osteoarthritis (OA) of the hip and knee, and examine possible variations in these preferences. METHODS: A stratified random sample of 1,001 rheumatologists in community-based practice in the United States was surveyed by mail. RESULTS: Responses were obtained form 594 subjects (529 white, 499 male, mean +/- SD age 47.4 +/- 8.1 years). Over 80% used acetaminophen or nonaspirin, nonsteroidal antiinflammatory drugs (NSAIDs) either always or frequently for the management of OA of the hip and knee. A majority used the following nonpharmacologic methods either always or frequently: weight loss, cane or crutch, physical and/or occupational therapy referral, and exercise. Variation in practice preferences was noted by age (< 47 versus > or = 47 years), sex, board certification in rheumatology, and number of patients seen per month. Respondents felt that severe pain and limitation of function were the most important factors in recommending total join arthroplasty for patients. CONCLUSION: These data demonstrate that practicing rheumatologists most often use either acetaminophen and/or NSAIDs in combination with nonpharmacologic methods in the medical management of OA of the hip and knee. The existence of variation in practice preferences has policy implications.

Aged↗
PubMed1996

Hepatocyte growth factor and its actions in growth plate chondrocytes.

Hepatocyte growth factor (HGF) has been implicated as a paracrine regulator of organogenesis and repair in many tissues. Here we have studied the expression and actions of HGF in intact rachitic rat growth plate and derived cultures of proliferative zone chondrocytes. In vivo and in vitro chondrocytes express HGF mRNA; 1,25(OH)2 has a three-fold maximal stimulatory effect, which can be blocked by H-7, an inhibitor of protein kinase C. Although HGF elaboration and action generally follow a paracrine model, chondrocytes appear capable of both expressing and responding to HGF. mRNA encoding the HGF receptor (c-met) was detected in both growth cartilage and derived chondrocyte cultures. HGF addition to chondrocyte cultures increased collagen II mRNA and alkaline phosphatase enzymatic activity to degrees comparable to that observed for active vitamin D metabolites. Combining HGF and 1,25-D evoked a synergistic response (ninefold) of alkaline phosphatase activity. To assess whether a similar stimulatory effect might be seen with bioactive peptides and HGF, we investigated the effect of HGF pretreatment on acute responses of chondrocytes to synthetic human calcitonin, an anabolic chondrocyte regulator whose skeletal action are mediated principally by cAMP elevation and subsequent protein kinase A activation. CT's maximal activation of protein kinase A was increased by prior HGF treatment from 56% to 78%. In concert, our findings indicate that in addition to HGF's classical paracrine role during skeletal growth, this growth factor may modulate hormonal sensitivity of the chondrocyte during proliferation, differentiation, and/or apoptosis.

Alkaline Phosphatase↗
PubMed1996

Clinical utility of bone mass measurements in adults: consensus of an international panel. The Society for Clinical Densitometry.

Low bone mass predicts future fracture risk as well as high cholesterol or high blood pressure can predict the risk of heart disease or stroke. Prevention of the first fracture should be a clinical goal. In patients without fractures, osteopenia and osteoporosis can be diagnosed based on the extent of reduction in bone mass below mean peak bone mass of young healthy individuals. As bone mass decreases, fracture risk increases exponentially. Clinical situations in which an assessment of bone mass and fracture risk affects therapeutic decisions include estrogen deficiency, vertebral abnormalities, radiographic osteopenia, asymptomatic primary hyperparathyroidism, and long-term corticosteroid therapy. Serial measurements can also be used to monitor the effects of osteoporosis treatments. The appropriate technique and skeletal site for bone mass measurements should be chosen based on the patient's circumstances and the precision of measurement. A clinical interpretation can enhance the value of computer-generated bone mass measurement reports and improve decision making.

Absorptiometry, Photon↗
PubMed1995

Guidelines for the medical management of osteoarthritis. Part I. Osteoarthritis of the hip. American College of Rheumatology.

Treatment of patients with OA of the hip should be individualized and tailored to the severity of the disease. In individuals with mildly symptomatic disease, treatment may be limited to patient education, physical and occupational therapy, other nonpharmacologic modalities, and drug therapy with a non-opioid oral analgesic. In patients who are unresponsive to this treatment regimen, the use of an NSAID in addition to nonpharmacologic therapy is appropriate unless it is medically contraindicated. Patients with severe symptomatic OA of the hip require an aggressive approach to decreasing pain, increasing mobility, and improving function; such patients may benefit from orthopedic consultation and evaluation for osteotomy or total joint arthroplasty.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1995

Guidelines for the medical management of osteoarthritis. Part II. Osteoarthritis of the knee. American College of Rheumatology.

Treatment of patients with OA of the knee should be individualized and tailored to the severity of the symptoms. In individuals with mild symptomatic OA, treatment may be limited to patient education, physical and occupational therapy and other nonpharmacologic modalities, and pharmacologic therapy including non-opioid oral and topical analgesics. In patients who are unresponsive to this treatment regimen, the use of NSAIDs in addition to nonpharmacologic therapy is appropriate unless medically contraindicated. Judicious use of intraarticular steroid injections has a role either as monotherapy or an adjunct to systemic therapy in patients with knee OA who have symptomatic effusions. The role of joint lavage and arthroscopic debridement in patients with OA of the knee who are unresponsive to conservative medical therapy needs further study, and these procedures cannot be routinely recommended for all patients at this time. Patients with severe symptomatic OA of the knee require an aggressive approach to decreasing pain, increasing mobility, and decreasing functional impairment; such patients may benefit from orthopedic consultation and evaluation for osteotomy or total joint arthroplasty.

Administration, Topical↗
PubMed1995

Effect of nonsteroidal antiinflammatory drugs on fracture healing: a laboratory study in rats.

We studied the effects of two nonsteroidal antiinflammatory drugs (NSAIDs) on fracture healing in rats: ibuprofen (30 mg/kg/day) and indomethacin (1 mg/kg/day). Femoral fractures were induced via a three-point bending technique. NSAIDs were administered orally for 4 or 12 weeks. Control animals received no medication. In each group a minimum of six animals were killed at the following intervals: 2, 4, 6, 8, 10, and 12 weeks postfracture. Fracture healing was determined by mechanical testing and histologic evaluation. The bending strength of each fractured femur was expressed as a percentage of the strength of the intact, contralateral femur. Histologic evaluation was performed on serial longitudinal sections stained with hematoxylin and eosin using a qualitative score of maturity of the callus. Ibuprofen and indomethacin both retarded fracture healing, with significant differences in "mechanical healing" found between the control and experimental groups after 10 weeks of drug administration. Both drugs also induced qualitative histologic changes manifested by delayed maturation of callus, which was noticeable earlier than the difference found by mechanical testing of bone. Our data suggest that NSAIDs have an inhibitory effect on fracture repair that is reversible after cessation of indomethacin but not ibuprofen.

Animals↗
PubMed1995

Fracture healing and mast cells.

We analyzed the morphology and localization of mast cells during the course of fracture repair in control rats and in animals with delayed healing of fractures induced by nonsteroidal antiinflammatory drugs (NSAIDs). In the first 2 weeks of fracture healing in control animals, mast cells were found either in the vicinity of blood vessels or in the vascularized tissue proliferating into the cartilaginous portion of subperiosteal callus. In the later stages (6-8 weeks), mast cells were seen in loose connective tissue in bone marrow surrounded with translucent ground substance. At this stage of healing, a hyperplasia of mast cells and cell degranulation was often seen in close proximity to osteoclasts and areas of bone resorption. Treatment with NSAIDs delayed fracture healing and the appearance of mast cell hyperplasia in bone marrow for approximately 4 weeks, suggesting that mast cells have specifically defined temporal and regional distribution during the process of bone repair. Histochemical studies documented a significant amount of chymase in the mast cells in callus. This enzyme was purified from mast cells by chromatography and was able to digest in vitro proteins extracted from bone. Our data suggest that mast cells in fracture healing are involved in digestion of extracellular matrix in callus tissue that could facilitate (a) angiogenesis in the early stages of healing, and (b) the replacement of provisional tissue with newly formed bone in the later stages of fracture healing.

Animals↗
PubMed1995

Cartilage metalloproteases in disuse atrophy.

A canine knee model of disuse atrophy produced by nonrigid fixation (sling) was characterized in respect to variables of proteoglycan size distribution, as well as biomechanical properties versus controls. Using this model, we found, in addition to the accepted dogma attributing changes to reduced protein synthesis by chondrocytes, that there is elevation of proteases and depression of tissue inhibitor of metalloproteases (TIMP) in atrophic knee cartilage. The findings are suggestive of cartilage remodelling reminiscent of bone remodelling in disuse atrophy reported by others. Whether the abnormal changes of protease-TIMP balance in knee cartilage can be retarded prophylactically by concurrent treatment with pentosan polysulfate and insulin like growth factor 1 remains uncertain.

Animals↗
PubMed1995

The classification of osteoarthritis.

The classification of osteoarthritis for clinical reports or trials has only recently become of interest. The ACR criteria for the knee, hip, and hand are the only research based criteria available. Modifications of these criteria will occur with testing, newer imaging techniques, and validation of serologic and synovial markers of disease. Much work is needed on expanding the classification criteria to other joints and other aspects of the clinical disease entity.

Guidelines as Topic↗
PubMed1995

Updated osteoarthritis reference standard.

The Kellgren and Lawrence atlas has been the reference standard for radiographic classification of osteoarthritis (OA) for nearly 40 years. Limitations include employment of a global grade, over-emphasis of the osteophyte, and submergence of other features so measurement of disease progression is difficult. Observer bias, drift, and variability cause concern. To address deficiencies and optimize observer accuracy, precision, and agreement, an updated atlas was created. From a photographic set of clinical radiographs, 4 readers selected a subset by consensus. Major radiographic features of hand, hip, and knee OA are graded on a 4-point scale. Using this atlas, it should be possible to individually score each relevant feature in a given joint. It is hoped the atlas will be adopted for population studies, assessment of disease progression, and protocols that evaluate new agents capable of modifying disease.

Hand↗
PubMed1995

Atlas of individual radiographic features in osteoarthritis.

Radiographs of the hand, hip and knee were screened for evidence of osteoarthritis (OA). Specific sites selected for screening on the postero-anterior radiographs of the hand included the base of the thumb with distal and proximal interphalangeal joints; these regions were examined for formation of marginal osteophytes, joint space narrowing and subchondral lucency. Sites selected from antero-posterior radiographs of the hip included the acetabular and femoral portions of the joint; these regions were examined for joint space narrowing, subchondral lucency, marginal osteophytes and subchondral sclerosis. Sites selected from antero-posterior weight-bearing radiographs of the knee included distal femora and proximal tibiae including the medial and lateral compartments; these regions were examined for joint space narrowing, marginal osteophytes and subchondral sclerosis. Sites selected from axial views of the patellofemoral joint examined the medial and lateral portions; these regions were examined for joint space narrowing, osteophytes, subluxations and subchondral sclerosis. A set of photographic prints was made from the collection of radiographs. These specific features of OA were graded on each print and a subset of prints was selected that best demonstrated the spectrum of severity for each feature of OA. This resultant atlas is offered as an updated guide to standardize interpretation of radiographs prior to and during clinical trials.

Cartilage, Articular↗
PubMed1994

Articular complications of Paget's disease of bone.

Articular symptoms in Paget's disease are very common. The most frequent cause of articular symptoms is OA, secondary to the Paget's disease. Radiographic OA due to Paget's disease is not always symptomatic, and periarticular Paget's disease does not invariably lead to OA. Intraarticular lidocaine occasionally is helpful in separating the symptoms of OA from those of Paget's disease.

Hip↗