Primary osteoarthritis: epidemiology, clinical aspects, and general management

Common variants in IL17F gene contributed to the risk of hip osteoarthritis susceptibility in Han Chinese population

AIM

The prevalence of hip and knee osteoarthritis (OA) varies by ethnicity, suggesting genetic heterogeneity in populations and predilection sites. Given the unknown mechanism of IL17F gene in the etiology of OA, it is necessary to examine the potential shared susceptibility of IL17F gene between knee OA and hip OA (HOA). This study aimed to evaluate the association of the IL17F gene and susceptibility to HOA in a Han Chinese population.

METHODS

A total of 2650 study subjects, comprising 796 HOA patients and 1854 controls, were recruited into the present study. Seven tag single nucleotide polymorphisms (SNPs) were selected for genotyping. Single marker-based genetic association analyses were conducted at both the genotypic and allelic levels. χ² statistics were calculated for statistical testing, and odds ratios were obtained to estimate the effects of genotypes and alleles for each SNP.

RESULTS

The SNP rs763780 was identified to be significantly associated with the risk of HOA at both genotypic (χ²  = 12.45, P = .002) and allelic levels (χ²  = 11.83, P = .0006). A linkage disequilibrium (LD) block comprised of 3 SNPs (rs12201582-rs12203736-rs722323) was also significantly associated with the risk of HOA. In addition, rs2294835 was identified to be associated with HOA severity (χ²  = 12.10, P = .02).

CONCLUSION

Our results showed that IL17F gene contributed to the risk of HOA in a Han Chinese population, which would help to elucidate the pathogenesis of OA and facilitate the development of novel medicines and treatments for OA.

Evaluation of the Relationship Between Common Variants in the TLR-9 Gene and Hip Osteoarthritis Susceptibility

Objective: Hip osteoarthritis (HOA) is one of the most common types of osteoarthritis and affects nearly 10% of men and 18% of women who are >60 years of age worldwide. It has been demonstrated to be a genetic disease with a 50% heritability risk. Recently, the TLR-9 gene has been associated with knee OA in both Turkish and Chinese populations, but the relationship between the TLR-9 gene and HOA has not been evaluated. In this study, we aimed to evaluate the relationship between the common genetic variants in the TLR-9 gene and the predisposition of Han Chinese individuals to HOA. Methods: A total of 730 HOA patients and 1220 healthy controls were recruited in a hospital-based case-control study. Six common single nucleotide polymorphisms (SNPs) of the TLR-9 gene were selected for genotyping, and genetic association analyses were performed using both single-marker and haplotype-based methods. Results: The SNP rs187084 was found to be significantly associated with the risk of HOA after a Bonferroni correction (adjusted allelic p-values with age, gender, and body mass index [BMI] = 0.0008). The results indicated that the A allele of rs187084 is a risk allele for HOA and is likely to be a predisposing factor leading to an increased risk of HOA (adjusted odds ratio with age, gender, and BMI = 1.26, 95% confidence interval = 1.10-1.43). The results of the haplotype analyses confirmed a similar pattern to the SNP analyses. Conclusions: Our study provides strong evidence that variations in the TLR-9 gene are closely linked with genetic susceptibility to HOA in the Han Chinese population. This finding furthers the role of TLR-9 in the development and occurrence of OA in general.

The influence of exercise on an unstable surface on the physical function and muscle strength of patients with osteoarthritis of the knee

[Purpose] This study investigated the influence of exercise on an unstable surface on ROM of the knee, muscle strength and the physical function of patients with osteoarthritis of the knee. [Subjects] The subjects were 30 patients diagnosed with degenerative osteoarthritis of the knee, they were divided into an experimental group (n=15) and a control group (n=15). [Methods] The experimental group performed exercise using an aero step XL (TOGU, Germany) 3 times a week, for 6 weeks. A control group performed the same exercise on a stable surface and without aero step XL. [Results] After the intervention, the experimental group showed statistically significant improvements in active knee flexion, knee joint manual muscle test (MMT), knee joint MMT hamstring and WOMAC score. [Conclusion] Exercise on the unstable surface improved the symptoms of patient with osteoarthritis. Exercise on an unstable surface might be helpful for improving the muscle strength and alignment of lower extremities as well as improving physical function related to the knee joint.

Lumbar spinal stenosis: who should be fused? An updated review

Lumbar spinal stenosis (LSS) is mostly caused by osteoarthritis (spondylosis). Clinically, the symptoms of patients with LSS can be categorized into two groups; regional (low back pain, stiffness, and so on) or radicular (spinal stenosis mainly presenting as neurogenic claudication). Both of these symptoms usually improve with appropriate conservative treatment, but in refractory cases, surgical intervention is occasionally indicated. In the patients who primarily complain of radiculopathy with an underlying biomechanically stable spine, a decompression surgery alone using a less invasive technique may be sufficient. Preoperatively, with the presence of indicators such as failed back surgery syndrome (revision surgery), degenerative instability, considerable essential deformity, symptomatic spondylolysis, refractory degenerative disc disease, and adjacent segment disease, lumbar fusion is probably recommended. Intraoperatively, in cases with extensive decompression associated with a wide disc space or insufficient bone stock, fusion is preferred. Instrumentation improves the fusion rate, but it is not necessarily associated with improved recovery rate and better functional outcome.

Osteoarthritis of the hand I: aetiology and pathogenesis, risk factors, investigation and diagnosis

Objective

Osteoarthritis (OA) of the hand can be a debilitating condition that hinders an individual's quality of life. With multiple joints within the hand that are commonly affected OA, an individual's ability to use their hand in everyday movements become more limited. The article aims to review literature on the aetiology and pathogenesis of OA, risk factors, characteristics of hand OA and the steps of diagnosis.

Key findings

The aetiology and pathogenesis of OA, in particular hand OA, is not fully understood. However, it is known that several factors play a role. Environmental factors, such as stress from mechanical loading, especially to vulnerable joints predispose individuals to developing OA. Extracellular matrix changes in protein levels have also been noted in individuals with OA. Linked to hand OA development are boney enlargements (Herbeden's and Bouchard's nodes). Several risk factors for OA include: age, obesity, gender, smoking, genetics, diet and occupation. Various diagnostic methods include a combination of using radiographic methods, clinical presentation, a number of developed measurements and scales.

Summary

With OA having several risk factors and various causes and contributing elements, it is important to elucidate the pathogenesis of OA and determine exactly how risk factors play a role in its development. Because of the contributions from several elements, diagnosis is best when it uses multiple methods. In turn, understanding OA and making better diagnoses could lead to improved management of the condition through both pharmacological and non-pharmacological interventions.

Laser-induced regeneration of cartilage

Laser radiation provides a means to control the fields of temperature and thermo mechanical stress, mass transfer, and modification of fine structure of the cartilage matrix. The aim of this outlook paper is to review physical and biological aspects of laser-induced regeneration of cartilage and to discuss the possibilities and prospects of its clinical applications. The problems and the pathways of tissue regeneration, the types and features of cartilage will be introduced first. Then we will review various actual and prospective approaches for cartilage repair; consider possible mechanisms of laser-induced regeneration. Finally, we present the results in laser regeneration of joints and spine disks cartilages and discuss some future applications of lasers in regenerative medicine.

The association between knee joint biomechanics and neuromuscular control and moderate knee osteoarthritis radiographic and pain severity

OBJECTIVE

The objective of this study was to determine the association between biomechanical and neuromuscular factors of clinically diagnosed mild to moderate knee osteoarthritis (OA) with radiographic severity and pain severity separately.

METHOD

Three-dimensional gait analysis and electromyography were performed on a group of 40 participants with clinically diagnosed mild to moderate medial knee OA. Associations between radiographic severity, defined using a visual analog radiographic score, and pain severity, defined with the pain subscale of the WOMAC osteoarthritis index, with knee joint kinematics and kinetics, electromyography patterns of periarticular knee muscles, BMI and gait speed were determined with correlation analyses. Multiple linear regression analyses of radiographic and pain severity were also explored.

RESULTS

Statistically significant correlations between radiographic severity and the overall magnitude of the knee adduction moment during stance (r²=21.4%, P=0.003) and the magnitude of the knee flexion angle during the gait cycle (r²=11.4%, P=0.03) were found. Significant correlations between pain and gait speed (r²=28.2%, P<0.0001), the activation patterns of the lateral gastrocnemius (r²=16.6%, P=0.009) and the medial hamstring (r²=10.3%, P=0.04) during gait were found. The combination of the magnitude of the knee adduction moment during stance and BMI explained a significant portion of the variability in radiographic severity (R(2)=27.1%, P<0.0001). No multivariate model explained pain severity better than gait speed alone.

CONCLUSIONS

This study suggests that some knee joint biomechanical variables are associated with structural knee OA severity measured from radiographs in clinically diagnosed mild to moderate levels of disease, but that pain severity is only reflected in gait speed and neuromuscular activation patterns. A combination of the knee adduction moment and BMI better explained structural knee OA severity than any individual factor alone.

Rofecoxib 12.5 mg, rofecoxib 25 mg, and celecoxib 200 mg in the treatment of symptomatic osteoarthritis: results of two similarly designed studies

OBJECTIVE

To compare the efficacy of rofecoxib and celecoxib for the treatment of knee or hip OA over 6 weeks.

METHODS

Two similarly designed, multicenter, randomized, double-blind, placebo-controlled studies. Patients were randomly assigned 3:3:3:1 in Study 1 to once daily (QD) rofecoxib 12.5 mg (N = 456), rofecoxib 25 mg (N = 459), celecoxib 200 mg (N = 456), or placebo (N = 150) and 3:3:1 in Study 2 to QD rofecoxib 25 mg (N = 471), celecoxib 200 mg (N = 460), or placebo (N = 151). There was no rofecoxib 12.5 mg arm in Study 2. The primary outcome measure of both studies was pain at night over 6 weeks for rofecoxib 25 mg vs. celecoxib 200 mg. Efficacy comparisons with rofecoxib 12.5 mg in Study 1 were included as pre-specified study objectives but not as pre-specified study hypotheses. Secondary endpoints included Patient Global Assessment of Response to Therapy (PGART) over 6 weeks and over 1 week. Safety was evaluated through the assessment of spontaneously reported adverse experiences (AEs), evaluation of vital signs, and laboratory data reported by investigators and patients.

RESULTS

For the primary endpoint, reduction in pain at night over 6 weeks in Study 1 was not significantly different between active treatments; in Study 2 rofecoxib 25 mg significantly (p = 0.023) reduced pain at night compared with celecoxib 200 mg over 6 weeks. For the secondary endpoints, in both studies, significantly (p < 0.05) more patients treated with rofecoxib 25 mg than celecoxib 200 mg had a good or excellent PGART over 6 weeks, and over the first week (p < 0.01). In both studies, there were no significant differences between active medications in the incidence of reported overall, serious, or drug-related AEs. The reported AE rates with the active treatments were generally similar to those with placebo in the two studies.

CONCLUSIONS

Rofecoxib 25 mg was significantly better than celecoxib 200 mg in relieving night pain at 6 weeks in one study; this was not confirmed in the accompanying study.

Ethnic-, gender-, and age-related differences in femorotibial angle, femoral antetorsion, and tibiofibular torsion: cross-sectional study among healthy Japanese and Australian Caucasians

The current study was conducted to examine ethnic, gender, and age-related differences in femorotibial angle (FTA), femoral antetorsion and tibiofibular torsion. Healthy Japanese (n = 120) and Australian Caucasian (n = 82) subjects were examined using a series of clinically reliable methods for measuring FTA and torsion of the lower limb. Subjects between 18-29 years of age were categorized as younger, 30-59 years as middle age, and 60 or more as older age. Three-way analysis of variance was utilized for data analysis. The Japanese subjects had significantly greater FTA (more varus) than the Australian subjects (P < 0.001). Femoral antetorsion in the Japanese subjects was significantly smaller in middle and older age groups than younger group (P < 0.05), but did not differ between the age groups in the Australian subjects. Further, tibiofibular torsion in female subjects was significantly greater in younger and middle age groups than the older age group (P < 0.01), but was not different between different age groups in males. The results suggest that healthy Japanese may have more genu varus alignment compared to the corresponding Australian population. Age-related ethnic and gender differences in femoral and tibiofibular torsion are worthy of further study.

The role of sequence variations within the genes encoding collagen II, IX and XI in non-syndromic, early-onset osteoarthritis

OBJECTIVE

We sought to determine whether sequence variations in cartilage collagen genes are associated with primary, early-onset osteoarthritis (OA).

METHODS

The cartilage collagen genes, COL2A1, COL9A1, COL9A2, COL9A3, COL11A1 and COL11A2, were screened for sequence variations in 72 Finnish probands and one US family with primary early-onset hip and/or knee OA. In addition, allelic association studies were performed using six to 12 common polymorphisms from each gene by genotyping 72 OA patients and 103 controls.

RESULTS

Altogether 239 sequence variations were found, of which 16 were not present in the controls. Seven of the unique variations, four in COL11A1, two in COL11A2 and one in COL2A1, were studied further, because they resulted in the substitution of conserved amino acids or were predicted to affect mRNA splicing. Co-segregation of a sequence variation and the phenotype was found in all four families available for study. Association analysis failed to identify any common predisposing alleles.

CONCLUSIONS

Early-onset OA demonstrates locus and allelic heterogeneity since the identified variations were in three different collagen genes and each of the six probands had a different mutation. It is also possible that some OA cases represent the mild end of the chondrodysplasia phenotypic spectrum. The major susceptibility alleles in this form of OA, however, remain to be identified.

The safety and efficacy of intraarticular hyaluronan with/without corticosteroid in knee osteoarthritis: 1-year, single-blind, randomized study

The goal of this study was to assess the safety and efficacy of hyaluronan (HA) with/without corticosteroid in patients with knee osteoarthritis (OA). In a 1-year, randomized, single-blind trial, 24 patients were treated with HA weekly for 3 weeks, then three injections on the 6th month for a total of six injections. Sixteen patients were treated the same but with the addition of 1 ml triamcinolone acetonide prior to the first and fourth HA injection. The treatment was repeated at the sixth month. The patients were evaluated with the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and the visual analog pain scale (VAS). After 1 year, progression of OA was evaluated with magnetic resonance imaging (MRI). During the study, pain relief was marked in patients who received combined treatment with respect to WOMAC pain and VAS (p<0.05). At the first year, no progression was observed in either treatment group. Although all patients had improvement for both pain and function, HA together with corticosteroid was superior to HA alone for early pain relief. The MRI findings showed that neither treatment showed a progression on the damage of the cartilage.

Pathogenesis of idiopathic scoliosis revisited

Scoliosis, a lateral deviation of the spine frequently associated with rotation, is not a specific disease but a deformity complicating many diseases. Curve progression is the major concern irrespective of the initiating cause. Idiopathic scoliosis is arguably postural in nature and in some subjects develops from intrauterine compression. Analysis of the pathogenesis leads to the conclusion that progression is due to an accelerated premature osteoarthrosis induced by insidious tissue fatigue of biomechanical origin. The chronic cumulative effect of repetitive tensile stresses applied asymmetrically to the postural deformity, manifested by loss of tensile strength and tissue cohesion, leads to fragility and eventual tissue disintegration of vertebrae, intervertebral discs, and laxity of ligaments. Early treatment, prevention, and avoidance of stresses that accentuate progression are of paramount import.

Gender and age-related differences in axial alignment of the lower limb among healthy Japanese volunteers: comparative and correlation study

A cross-sectional study was designed for this investigation using a healthy Japanese population. The objectives of this study were to confirm gender and age-related differences in axial alignment of the lower limb, and to investigate the correlation between femorotibial angle and axial alignment of the lower limb among a healthy Japanese population. Although axial alignment of the lower limb has been defined as one of the associating factors for osteoarthritis of the knee along with varus and valgus deformity, the results in the literature are inconsistent. Since there is gender difference in femorotibial angle, axial alignment of the lower limb should show the difference if it is an associating factor for osteoarthritis of the knee. Few studies have been conducted to investigate gender difference in axial alignment of the lower limb. One hundred and forty four healthy Japanese subjects took part in the study. Reliable clinical methods of measuring femoral torsion, tibiofibular torsion, rotational range of motion of the hip and knee joints, and femorotibial angle were employed utilizing a digital inclinometer. Two way ANOVA and Pearson product-moment correlation analysis were used for statistical analyses. Axial alignment of the lower limb was different between genders (p<0.05). An age-related difference was also shown in hip rotation (p<0.05). Further, the femorotibial angle was significantly correlated with hip and knee joint rotation (p<0.05) in older males and younger females. This study implied that axial alignment of the lower limb may be related to deformity of the knee joint.

Clinical, radiologic, demographic, and occupational aspects of hand osteoarthritis in the elderly

OBJECTIVE

Osteoarthritis (OA) of the hand is common in elderly patients. The aim of this study was to characterize OA frequency, severity, and distribution and to trace interrelationships between these findings and the demographic, occupational, and medical data from elderly Jewish nonrheumatologic patients.

METHODS

Study participants were 253 consecutive patients admitted to a geriatric center for a variety of nonrheumatic medical conditions. Excluded patients were those with rheumatoid arthritis; neurologic, orthopedic, or other conditions that would interfere with symmetric hand function; and mental or medical states that would interfere with history taking and radiographic studies. Patient occupations were graded as workload degree (on a scale of 1 to 3) and as the total occupational score (workload degree multiplied by the duration of each job). Clinical findings of Heberden nodes, Bouchard nodes, and malignment, graded on a scale of 0 to 3, were summed as the clinical OA score. Hand radiographs were independently read (modified Altman method), grading 5 parameters in each joint on a scale of 0 to 3, summed as a radiologic OA score. Statistical analyses included the Student t test, chi(2) test, ANOVA, Pearson correlation, and partial correlation coefficients.

RESULTS

Among 253 elderly patients (171 women, 82 men; mean age, 79 years) OA was frequent (occurring in about 80% of patients), involving most severely the second and third distal interphalangeal, right first interphalangeal, and both first carpometacarpal joints. The prevalence of OA was similar in women and men, with higher scores in women, and reached significance only in the distal interphalangeal joints. Metacarpophalangeal joints were more involved in men. Age had a clear influence on OA scores. Ethnicity affected OA severity, with Ashkenazi Jews having significantly higher scores than Sepharadi Jews. Dominant hands had significantly higher global OA scores as well as isolated joint scores (except for the first carpometacarpal joint). Occupational load, housekeeping tasks, and the number of children did not influence the total or specific joint OA scores. Associated conditions such as obesity, diabetes, hypothyroidism, and chondro calcinosis were not associated with more pronounced OA.

CONCLUSIONS

Hand OA was prevalent in our elderly cohort, and its severity was influenced by inherent traits such as age, female gender, ethnicity, and handedness. In contrast, acquired factors such as workload, number of children, and associated diseases did not appear to influence OA expression.

The impact of hemiparalysis on the expression of osteoarthritis

OBJECTIVE

Primary generalized osteoarthritis (OA), the most prevalent joint disease, is usually symmetric. Sporadic case reports mention decreased OA manifestations in limbs in which there are neurologic deficits, but no systematic research has been published. The aim of the present study was to examine these observations in a planned and controlled survey in a group of patients with OA.

METHODS

Seventy-five geriatric patients with a history of stroke and hemiparalysis were studied clinically and radiographically (hand radiographs; graded according to a modified Altman method) for the presence and the degree of OA in the hands. Detailed clinical and radiologic scores were calculated for each hand. Demographic, occupational, and neurologic data were collected. Patients with other joint or neurologic conditions were excluded. A group of 55 elderly patients without stroke were similarly studied (controls). Scores in the paralyzed hand were compared with those in the nonparalyzed hand in the stroke patients and subgroups (by Student's paired t-test and Wilcoxon test). Scores in the dominant hands were compared with those in the nondominant hands in stroke patients and control subjects (by Student's paired t-test and Mann-Whitney test). Correlation between the degree of neurologic damage and OA asymmetry (Pearson's correlation coefficient) was also sought.

RESULTS

Paralyzed hands showed significantly fewer OA changes than nonparalyzed hands, both clinically and radiologically. This trend, accentuated in patients with more severe paralysis, disappeared in those with mild residual paresis. Asymmetry of OA was more pronounced in patients with flaccid, compared with spastic, paralysis. The degree of paralysis and loss of muscle strength correlated with the degree of OA asymmetry. Women had significantly higher OA scores than men. In the control group, dominant hands had higher OA scores, but this finding was concealed among hemiparalyzed patients. Lifetime gross occupational load and present grip strength did not correlate with the degree of OA.

CONCLUSION

In elderly patients, hemiparalysis reduces ipsilateral hand expression of OA, while OA is accentuated (or increased) in the dominant hand of patients without paralysis. This first systematic study confirms the findings of previous case reports and lends support to the role of biomechanical factors in the development of OA.

Acetabular pressures during hip arthritis exercises

OBJECTIVE

To examine in vivo maximum acetabular contact pressures during gait and hip arthritis exercises recommended by clinicians and the Arthritis Foundation.

METHODS

Acetabular contact pressure data were collected for 2.5 years, at 3-4-month intervals, from an instrumented endoprosthesis implanted in an 84-year-old male who had sustained a left hip fracture. Maximum pressure data were compared for each activity.

RESULTS

Mean pressures ranged from 9.0 +/- 2.3 megapascals (MPa) during maximum isometric hip abduction, 9.0 +/- 0.8 MPa during standing right hip abduction, and 8.9 +/- 2.8 MPa during standing left hip abduction to 1.2 +/- 0.3 MPa during quiet standing. Free-speed gait pressure averaged 5.6 +/- 0.9 MPa. The maximum mean pressure during side-lying hip abduction and straight leg raise at 30 degrees/second were less than the same activities at 60 degrees/second.

CONCLUSIONS

These in vivo hip pressure measurements challenge traditional protocols for patients with hip osteoarthritis and provide quantitative data as a framework for designing exercise programs. Maximum isometric hip exercise and standing exercise generated much higher hip pressures, and are therefore probably more stressful to acetabular cartilage, than gait or stationary cycling. Clinicians must consider exercise velocity because of its direct correlation with hip contact pressure. Walking generated lower pressure than most activities studied and, given its other benefits, is therefore probably beneficial for patients with hip osteoarthritis.

The role of adjunctive therapy in the management of chronic nonmalignant pain

The management of chronic nonmalignant pain is an increasing challenge to clinicians and their patients. Adjunctive therapy, which includes a wide range of physical, psychoeducational, and multidisciplinary interventions, can play an important role in the treatment of pain. This article discusses the role and efficacy of adjunctive therapy in the management of pain associated with musculoskeletal conditions, the most common and disabling sources of chronic nonmalignant pain. Findings from meta-analyses, review articles, and recent clinical trials are reviewed that suggest that interventions that combine exercise and psychoeducational approaches designed to enhance communication, control, problem-solving, and coping can have a clinically significant impact on reducing pain and improving functional status for many conditions.

Frequency of stress lesions of the upper gastrointestinal tract in paediatric patients after cardiac surgery: effects of prophylaxis

BACKGROUND

Stress lesions of the upper gastrointestinal tract are well recognised in adult patients in intensive care. There are no controlled studies of the incidence of these lesions and the effects or side effects of prophylactic treatment in high risk paediatric patients.

METHODS

79 paediatric patients in intensive care were studied prospectively after operation for congenital heart disease. All patients had at least one endoscopic examination. The first 36 patients were not given prophylactic medication: later 43 children were treated randomly either with pirenzepine (n = 21) or with famotidine (n = 22). Gastric and tracheal secretions were taken daily for culture in those patients given prophylactic medication.

RESULTS

Severe inflammation or ulceration of the upper gastrointestinal tract was less common in those patients who were given prophylactic medication (18% v 44%). Prophylactic treatment did not, however, reduce the total incidence of postoperative stress lesions: it shifted the severity of these changes towards mild lesions and reduced the incidence of ulcerations from 25% to 2%. None of the patients developed a pneumonia caused by an organism previously isolated from the stomach.

CONCLUSIONS

The incidence of stress lesions in children after cardiac surgery resembles that in high risk adult patients. Children in intensive care after cardiac surgery should be treated prophylactically with famotidine or pirenzepine until they can be fed by mouth.

Comparative study of the intrinsic mechanical properties of the human acetabular and femoral head cartilage

Biphasic creep indentation methodology and an automated indentation apparatus were used to measure the aggregate modulus, Poisson's ratio, permeability, thickness, creep and recovery equilibrium times, and percentage of recovery of normal articular cartilage in 10 human hip joints. These properties were mapped regionally to examine the mechanical factors involved in the development of site-specific degenerative lesions in the acetabulum and femoral head. The results indicate that there are significant differences between these properties regionally in the acetabulum and femoral head and between the two anatomical structures. Specifically, it was found that cartilage in the superomedial aspect of the femoral head has a 41% larger aggregate modulus than its anatomically corresponding articulating surface in the acetabulum. In addition, the superomedial aspect of the femoral head has the greatest aggregate modulus (1.816 MPa) within the hip joint. During sitting, the inferior portion of the femoral head is in contact with the anterior acetabulum, and the anterior acetabulum has a 53% greater aggregate modulus than the inferior femoral head. This area below the fovea on the femoral head has the least aggregate modulus (0.814 MPa) within the hip joint. These mismatches in the compressive modulus of opposing articulating surfaces may contribute to degeneration of cartilage in the superomedial acetabulum and the inferior femoral head. Our findings support the clinical observation that these areas are frequent sites of early degeneration.

A walking education program for patients with osteoarthritis of the knee: theory and intervention strategies

Walking is an ideal physical activity for patients with osteoarthritis because it can help to improve functional status without exacerbating pain or necessitating an increase in the use of medication. Although patient education programs designed to encourage walking have become increasingly important in the management of this condition, there is no single synthesis or other published source of theory and intervention strategies to guide the practitioner in the development of such programs. This paper describes a hospital-based patient education program designed to enhance the functional capacity of who have osteoarthritis of the knee by encouraging the adoption and maintenance of walking. The paper describes the goals, objectives, process, and impact of the program; the principal theoretical model utilized in the design of the program; and how concepts and intervention strategies from the literatures on patient compliance and patient education, exercise compliance, behavioral psychology, and relapse prevention have been operationalized and integrated in a walking program that we have evaluated for safety and efficacy.

Comparison of selected health behavior variables in elderly women with osteoarthritis in different environments

Hardiness, social support, perceived health, functional independence, and use of health care facilities were compared in this descriptive study of 45 elderly women with osteoarthritis living in three different environments--urban, rural, and frontier. All participants were between the ages of 65 and 75 years and were residing in their own homes. Statistical differences were found between groups in overall perceived health and functional independence; the frontier sample perceived their health as better and themselves as more functionally independent than the urban or the rural sample. No statistical differences were found in levels of hardiness or perceived social support between the three groups. Use of health care facilities varied among participant groups by environmental context; the urban group made more use of facilities than the rural or frontier group, and the rural group used more facilities than the frontier group.

Conservative and medical management of hip dysplasia

Hip dysplasia has been managed conservatively and medically since the initial description of this disease in 1935. However, little factual information is known about the benefits of the various forms of conservative and medical management. Nonsteroidal anti-inflammatory drugs have been a mainstay of treatment, with the only real debate being which NSAID to use. Only with the recent anecdotal reports of polysulfated glycosaminoglycan has there been any change in medical management of CHD, and this method of treatment warrants further investigation. Conservative and medical management definitely have a role in the treatment of CHD. It must be remembered, however that CHD is primarily a disease of biomechanical alterations and joint laxity, with the cartilage effects being secondary. With a great enough degree of laxity, coxofemoral incongruency, articular damage, or osteoarthritic change, conservative and medical management will not be effective. At that stage, surgical management must be considered.

Mobility impairment in the elderly: challenges for biomechanics research

The problems of mobility impairment in the elderly constitute new and major challenges for biomechanics research. This paper outlines what some of the important problems are, discusses the relevance of biomechanics research to these problems, and reviews some of the current state of knowledge about factors related to the biomechanics of mobility impairments in the elderly. The population of old adults is growing rapidly and the incidence of mobility impairments in old adults is high. Mobility impairment biomechanics research is needed to make the assessments of impairments more precise, to design therapeutic programs that are more effective and to learn more about how mobility impairments can be prevented.

Osteoarthritis in women: its relationship to estrogen and current trends

With our expanding knowledge of osteoarthritis (OA) over the years, our concept of this "aging" disease has been re-evaluated to that which is the opposite of traditional views. To clinicians and scientists, OA is no longer the inevitable disease of aging, as one conceptualizes gray hair. Epidemiological studies show a higher incidence of OA affecting polyarticular joints in women than age-matched men, particularly those over the age of 55. This discrepancy in sex difference in the OA incidence highlights the significance of sex hormones and their alterations in menopause. Evidence indicates that this alteration possibly occurs early in adult life and may well persist into menopause. As well, this hormonal perturbation is thought to be consequent to obesity in these women. Both in vivo and in vitro studies suggest that estrogen is chondrodestructive via the receptor-mediated mechanism. The finding of estrogen receptor in canine, rabbit, and human articular cartilage further confirms this hypothesis. Recent findings of elevated synovial estradiol level and higher estrogen receptor bindings in human osteoarthritic cartilage strongly suggest the importance of local uptake of estradiol (E2) and the possible up-regulation of estrogen receptors. Estrogen, like other hypothesized etiologies, is important in the development of OA in women.

Passive role of articular chondrocytes in the pathogenesis of acute meniscectomy-induced cartilage degeneration

The importance of viable articular chondrocytes and enzymes or factors from surgically traumatized synovium in the pathogenesis of acute meniscectomy-induced cartilage degeneration was examined in guinea pigs (nine groups of five animals each). Iodoacetate injected intra-articularly was used to kill articular chondrocytes of guinea pigs prior to meniscectomy to determine if they were active participants in the acute lesion induction. Lesions of similar severity to those occurring in animals with viable chondrocytes at the time of surgery were observed, suggesting that the chondrocytes were not actively involved in the pathogenesis in this group. In an additional group of guinea pigs in which chondrocytes were killed by iodoacetate, the medial collateral ligament was transected to determine if acute degenerative changes could be induced in acellular cartilage exposed to a surgical manipulation that does not by itself induce lesions but does expose cartilage to enzymes/factors from traumatized synovium. Transecting the medial collateral ligament and entering the joint space without induction of instability via meniscectomy did not result in histologic evidence of cartilage damage. This suggests that synovial trauma and mild inflammation were insufficient to induce matrix degeneration in the absence of abnormal load bearing. In further support of this, guinea pigs subjected to unilateral sciatic neurectomy at the time of meniscectomy were protected against development of acute cartilage degeneration. Results of this study suggest that articular cartilage devoid of viable chondrocytes at the time of meniscectomy responds acutely in much the same way as intact cartilage subjected to this procedure.

Plasma hyaluronan levels in rabbit immobilization osteoarthritis: effect of remobilization

The right knee joint of 11 rabbits was immobilized in full extension with a splint for a period of three days. The effect of the immobilization and subsequent remobilization on plasma hyaluronan (HA) level was measured, using a sensitive radiometric HA binding protein (125I-HABP) assay. No significant effect of the immobilization on plasma HA level (54 +/- 4 micrograms/l) was noted, but shortly (45 minutes) after splint removal, plasma hyaluronate was at its highest (91 +/- 20 micrograms/l). One day after removal of the splint a return to baseline (53 +/- 6 micrograms/l) was observed. It is suggested that HA may accumulate in the joint during immobilization. Shortly after removing the splint, the level of HA shows a rise in many of the rabbits, even if this is not a consistent finding, probably due to variation in the extent and kinetics of the HA mobilization. Such an accumulation of HA could be deleterious for joint tissues, since HA is an-effective stimulator of interleukin-1 (also called catabolin) synthesis and secretion, and since immobilization osteoarthritis ensues in the splinted rabbit joints.

Predisposition to familial osteoarthrosis linked to type II collagen gene

The genetic background of two families, in whom a predisposition to primary osteoarthrosis is inherited as a dominant trait, was investigated. Use of restriction fragment length polymorphisms within and around the type II collagen gene on chromosome 12 revealed a linkage between this cartilage-specific gene and primary osteoarthrosis.

Does Running Cause Osteoarthritis?

In brief: This review of the literature on exercise and arthritis considers the relevant epidemiologic and experimental studies of animals and humans, with a focus on the relationship between running and osteoarthritis. The cause of osteoarthritis-the most common joint disease in the United States-remains unknown. The incidence of the disease increases with age and eventually afflicts most people-athletes and nonathletes alike-to some extent: Almost everyone has some pathologic abnormality in the weight-bearing joints by age 40 or 50; by age 75 at least 85% of all people have diagnosable osteoarthritis. However, there is no conclusive evidence that running causes the disease; in fact, running may actually slow the functional aspects of musculoskeletal aging.