Über die Arthritis deformans

First Metatarsophalangeal Joint Implant Options

Evidence-based medicine continues to guide our treatment of patients. Owing to the unique characteristics of the first metatarsophalangeal joint (1^st MTPJ) with its small surface area and the significant amount of multiplanar force that affects it, finding the perfect implant to allow motion and alleviate pain is still the ultimate goal. While some of the older metallic implants and silastic spacers may still be providing pain relief and function to patients, the majority have failed and caused significant bone loss along the way. The HemiCap implants have shown some promise in select patients and may still be a viable option in patients desiring maintenance of 1st MTPJ motion.

Is it appropriate to measure age-related lumbar disc degeneration on the mid-sagittal MR image? A quantitative image study

PURPOSE

Even though phenotypes of disc degeneration vary on different sagittal magnetic resonance images (MRI), measurements typically are acquired on the mid-sagittal MRI. This study investigated the appropriateness of using the mid-sagittal MRI to measure various phenotypes of age-related disc degeneration.

METHODS

Lumbar spine MRIs of 66 subjects (mean age 50.3 years, standard deviation 16.5 years, range 22-84 years) were studied. An image analysis program Spine Explorer was used to obtain quantitative measurements for disc height, bulging, and signal on para- and mid-sagittal T2-weighted MRIs. Measurements on para- and mid-sagittal MRIs and their associations with age were compared.

RESULTS

Measurements of disc height, signal, and posterior disc bulging acquired on the mid-sagittal MRI were greater than those on the para-sagittal MRIs. Disc height measurements were not linearly associated with age. Greater age was correlated with greater anterior (r = 0.45, P < 0.001) and posterior (r = 0.33, P < 0.01) bulging on para-sagittal MRIs, but not posterior disc bulging on the mid-sagittal MRI (r = - 0.10, P > 0.05). Disc signal intensity measurements on the mid-sagittal MRI had stronger correlations with age than those on para-sagittal MRIs. Mean and standard deviation of disc signal intensity acquired on the mid-sagittal MRI had the strongest correlations with age among all measures of disc degeneration studied (r = - 0.50, - 0.67, respectively, P < 0.001 for both).

CONCLUSIONS

Disc signal measurements acquired on the mid-sagittal MRI were reliable and had strong correlations with age and thus can be used as an appropriate measure of disc degeneration. Disc bulging had better be measured on para-sagittal MRIs. Although severe disc narrowing clearly is a sign of severe disc degeneration, disc height was not linearly associated with age.

Correlation of Macroscopic Osteoarthrotic Changes and Radiographic Findings in the Acromioclavicular Joint

In a total of 108 acromioclavicular articulations from cadavers the osteoarthrotic changes were studied. The articulations were macroscopically and radiographically ranked according to their grade of osteoarthrosis. The two ranking lines were correlated statistically and showed a rank correlation of 0.741. In 38 articulations tomography was also carried out. These articulations were classified into five grades of osteoarthrosis and the macroscopic, conventional radiographic and tomographic gradings were compared. The correlation coefficient for tomography versus macroscopy was 0.714. Tomography versus standard radiography showed a correlation of 0.767 and standard radiography versus macroscopy a correlation of 0.841. The standard radiographic investigation reveals moderate and severe osteoarthrotic changes in the acromioclavicular joint but cannot depict smaller changes. Tomography does not seem to improve the specificity. There is a need for a better radiologic technique in the examination of the acromioclavicular joint. Radiography during some kind of loading might be a practical way of improving the specificity and make it possible to show early osteoarthrosis in the acromioclavicular articulation.

Radiological prevalence of degenerative arthritis of the first metatarsophalangeal joint

BACKGROUND

The prevalence of osteoarthritis of the first metatarsophalangeal joint (MTPJ) has not been completely determined in a population-based study. The aim of the study was to determine the age- and gender-related prevalence of radiological first MTPJ arthritis.

METHODS

We analyzed 517 consecutive radiographs of adult patients who presented with acute foot injuries to the accident and emergency department over a 6-month period. Radiographs were assessed independently by 2 authors using the Hattrup and Johnson grading system for osteoarthritic changes in the first MTPJ.

RESULTS

The radiographic prevalence of MTPJ arthritis in our population was 25% (127/517). Overall incidence was higher in females, with 32% (85/269) of females affected in comparison to 18% (44/248) of males. Variance between the sexes was insignificant until the age of 60, at which point the prevalence rose to 66% (53/80) in females compared with 47% (18/38) in males of the same age.

CONCLUSIONS

The development of first MTPJ arthritis follows a typical pattern of degenerative arthritis, as shown in other joints, with increasing age being an important factor. The results of this study suggest that first MTPJ arthritis begins to appear in most cases in middle age and is significantly more apparent in females.

LEVEL OF EVIDENCE

Level III, comparative case series.

Periarticular osteophytes as an appendicular joint stress marker (JSM): analysis in a contemporary Japanese skeletal collection

Objective

The aim of this study was to investigate the possibility that periarticular osteophytes plays a role as a appendicular joint stress marker (JSM) which reflects the biomechanical stresses on individuals and populations.

Methods

A total of 366 contemporary Japanese skeletons (231 males, 135 females) were examined closely to evaluate the periarticular osteophytes of six major joints, the shoulder, elbow, wrist, hip, knee, and ankle and osteophyte scores (OS) were determined using an original grading system. These scores were aggregated and analyzed statistically from some viewpoints.

Results

All of the OS for the respective joints were correlated logarithmically with the age-at-death of the individuals. For 70 individuals, in whom both sides of all six joints were evaluated without missing values, the age-standardized OS were calculated. A right side dominancy was recognized in the joints of the upper extremities, shoulder and wrist joints, and the bilateral correlations were large in the three joints on the lower extremity. For the shoulder joint and the hip joint, it was inferred by some distinctions that systemic factors were relatively large. All of these six joints could be assorted by the extent of systemic and local factors on osteophytes formation. Moreover, when the age-standardized OS of all the joints was summed up, some individuals had significantly high total scores, and others had significantly low total scores; namely, all of the individuals varied greatly in their systemic predisposition for osteophytes formation.

Conclusions

This study demonstrated the significance of periarticular osteophytes; the evaluating system for OS could be used to detect differences among joints and individuals. Periarticular osteophytes could be applied as an appendicular joint stress marker (JSM); by applying OS evaluating system for skeletal populations, intra-skeletal and inter-skeletal variations in biomechanical stresses throughout the lives could be clarified.

Disparities in rates of spine surgery for degenerative spine disease between HIV-infected and uninfected veterans

STUDY DESIGN

Retrospective analysis of nationwide Veterans Health Administration clinical and administrative data.

OBJECTIVE

Examine the association between HIV infection and the rate of spine surgery for degenerative spine disease.

SUMMARY OF BACKGROUND DATA

Combination antiretroviral therapy has prolonged survival in HIV-infected patients, increasing the prevalence of chronic conditions such as degenerative spine disease that may require spine surgery.

METHODS

We studied all HIV-infected patients under care in the Veterans Health Administration from 1996 to 2008 (n = 40,038) and uninfected comparator patients (n = 79,039) matched on age, sex, race, year, and geographic region. The primary outcome was spine surgery for degenerative spine disease, defined by International Classification of Diseases, Ninth Revision procedure and diagnosis codes. We used a multivariate Poisson regression to model spine surgery rates by HIV infection status, adjusting for factors that might affect suitability for surgery (demographics, year, comorbidities, body mass index, combination antiretroviral therapy, and laboratory values).

RESULTS

Two hundred twenty-eight HIV-infected and 784 uninfected patients underwent spine surgery for degenerative spine disease during 700,731 patient-years of follow-up (1.44 surgeries per 1000 patient-years). The most common procedures were spinal decompression (50%) and decompression and fusion (33%); the most common surgical sites were the lumbosacral (50%) and cervical (40%) spine. Adjusted rates of surgery were lower for HIV-infected patients (0.86 per 1000 patient-years of follow-up) than for uninfected patients (1.41 per 1000 patient-years; incidence rate ratio 0.61, 95% confidence interval: 0.51-0.74, P < 0.001). Among HIV-infected patients, there was a trend toward lower rates of spine surgery in patients with detectable viral load levels (incidence rate ratio 0.76, 95% confidence interval: 0.55-1.05, P = 0.099).

CONCLUSION

In the Veterans Health Administration, HIV-infected patients experience significantly reduced rates of surgery for degenerative spine disease. Possible explanations include disease prevalence, emphasis on treatment of nonspine HIV-related symptoms, surgical referral patterns, impact of HIV on surgery risk-benefit ratio, patient preferences, and surgeon bias.

Vascular cell adhesion molecule 1 as a predictor of severe osteoarthritis of the hip and knee joints

OBJECTIVE

Osteoarthritis (OA) is a leading cause of pain and physical disability in middle-aged and older individuals. We undertook this study to determine predictors of the development of severe OA, apart from age and overweight.

METHODS

Joint replacement surgery due to severe hip or knee OA was recorded over a 15-year period in the prospective Bruneck cohort study. Demographic characteristics and lifestyle and biochemical variables, including the level of soluble vascular cell adhesion molecule 1 (VCAM-1), were assessed at the 1990 baseline visit and tested as predictors of joint replacement surgery.

RESULTS

Between 1990 and 2005, hip or knee joint replacement due to OA was performed in 60 subjects. VCAM-1 level emerged as a highly significant predictor of the risk of joint replacement surgery. Intervention rates were 1.9, 4.2, and 10.1 per 1,000 person-years in the first, second, and third tertiles, of the VCAM-1 level, respectively. In multivariable logistic regression analysis, the adjusted relative risk of joint replacement surgery in the highest versus the lowest tertile group of VCAM-1 level was 3.9 (95% confidence interval 1.7-8.7) (P<0.001). Findings were robust in various sensitivity analyses and were consistent in subgroups. Addition of the VCAM-1 level to a risk model already including age, sex, and body mass index resulted in significant gains in model discrimination (C statistic) and calibration and in more accurate risk classification of individual participants.

CONCLUSION

The level of soluble VCAM-1 emerged as a strong and independent predictor of the risk of hip and knee joint replacement due to severe OA. If our findings can be reproduced in other epidemiologic cohorts, they will assist in routine risk classification and will contribute to a better understanding of the etiology of OA.

How much are radiological parameters related to clinical symptoms and function in osteoarthritis of the shoulder?

Loss of joint space, formation of osteophytes and deformation are common features of osteoarthritis. Little information exists about the radiological features of arthrosis in relation to clinical findings and the radiological appearance in degenerative shoulder joint disease especially with regard to decision making about the timing of joint replacement. We retrospectively examined 120 standardised X-rays of patients with advanced osteoarthritis of the shoulder. Exclusion criteria included rotator cuff tear, severe glenoid erosion or protrusion. Measurements of joint space width at three levels in each plane (anteroposterior and axillary view), humeral head diameter and size of humeral osteophytes were made by two independent examiners. Osteoarthritis was graded according to Samilson and Prieto. Seventy-five of these patients had a complete record from the clinical investigation (pain record on VAS scale, active and passive range of motion) and the constant score (CS). Mean joint space width in the central anteroposterior level was 1.46 mm +/- 1.08 and in the central axillary 0.98 mm +/- 1.02. Increasing age was positively correlated with joint space narrowing at all measured levels. The joint space width was not correlated with the Samilson grade or the size of osteophytes. The joint space width was neither correlated with pain nor active or passive ROM. Pain was correlated with active and passive flexion and abduction but not for internal or external rotation. The size of the osteophytes was negatively correlated (active and passive) with flexion, abduction and external and internal rotation. The study illustrates that joint space narrowing and development of osteophytes are reliable but independent parameters of primary shoulder arthrosis and should be recorded separately. The size of the caudal humeral osteophyte is a predictive factor for function and should be taken into account for clinical decision making. The primary clinical feature, pain, as the main indication for surgery is not related to radiological parameters.

Lumbar spondylosis: clinical presentation and treatment approaches

Low back pain (LBP) affects approximately 60-85% of adults during some point in their lives. Fortunately, for the large majority of individuals, symptoms are mild and transient, with 90% subsiding within 6 weeks. Chronic low back pain, defined as pain symptoms persisting beyond 3 months, affects an estimated 15-45% of the population. For the minority with intractable symptoms, the impact on quality of life and economic implications are considerable. Despite the high prevalence of low back pain within the general population, the diagnostic approach and therapeutic options are diverse and often inconsistent, resulting in rising costs and variability in management throughout the country. In part, this is due to the difficulty establishing a clear etiology for most patients, with known nociceptive pain generators identified throughout the axial spine. Back pain has been termed as "an illness in search of a disease." Indeed, once "red flag" diagnoses such as cancer and fracture have been ruled out, the differential sources of low back pain remain broad, including the extensive realm of degenerative changes within the axial spine for which radiological evaluation is nonspecific and causal relationships are tentative. We will elaborate on these degenerative processes and their clinical implications. We will further discuss diagnostic approaches and the efficacy of existing treatment options.

Osteoarthritis: an example of phenoptosis through autonomic dysfunction?

Phenoptosis, the programmed death of organisms akin to cellular apoptosis, constitutes a type of Darwinian selection that enhances inclusive fitness. It provides a means by which senescent and pre-senescent members can self-terminate if they have incurred sufficient cumulative stress such that their continued survival detracts from inclusive fitness. Sepsis, vascular disease, menopause, cancer, and aging all represent examples of phenoptosis at work. We previously proposed that feed-forward autonomic dysfunction fundamentally drives phenoptosis in all its guises. Accordingly, we now postulate that osteoarthritis defines a type of biomechanical phenoptosis, mediated by feed-forward autonomic dysfunction, and manifested through joint destruction associated with fitness disadvantages. Biomechanical capability plays a significant role in evolutionary fitness, and sustained joint insults such as immobility or undue biomechanical stress may serve as proxies for inferior fitness. By both hindering an individual's ability to compete for energy and increasing that individual's vulnerability to predation, feed-forward joint destruction may facilitate adaptive phenoptosis among impaired or senile members. Empirical data suggests that contrary to common belief, heavy joint use does not necessarily cause osteoarthritis, whereas immobility and neuropathy can predispose to the condition. From a Darwinian perspective, another process mediated by sympathetic activity, the alarm cry of attacked prey, simultaneously promotes the escape of kin while attracting predators and scavengers. By effectively enabling the martyrdom of biomechanically-challenged individuals, osteoarthritis may serve to optimize system energy efficiency in a similar fashion. This framework may generalize to other situations where regenerative capacity dissipates in conjunction with maturation, typically leading to fibrosis. By allowing environmental pressure to sort the phenotypes, imperfect repair mechanisms may accelerate adaptation and optimize long-term inclusive fitness for all individuals. As the basis of competition shifts from biomechanical to cognitive skills, and as novel triggers for physical stress emerge, osteoarthritis may now represent a modern maladaptation.

Lumbar disc degeneration: epidemiology and genetics

Research conducted over the past decade has led to a dramatic shift in the understanding of disc degeneration and its etiology. Previously, heavy physical loading-often associated with occupation-was the main suspected risk factor for disc degeneration, which was commonly viewed as a wear-and-tear phenomenon exacerbated by the precarious nutritional status of the disc. However, results of studies on twins suggest that physical loading specific to occupation and sport plays a relatively minor role in disc degeneration. Recent research indicates that heredity has a dominant role in disc degeneration, which would explain the variance of up to 74% seen in adult populations that have been studied to date. Since 1998, genetic influences have been confirmed by the identification of several gene forms associated with disc degeneration. This research is paving the way for a better understanding of the biologic mechanisms through which disc degeneration occurs, including specific interactions between genes and environment. Research into disc degeneration and genetics has become more limited by phenotypes or definitions and measures of disc degeneration than by DNA analysis. Standardized, universally accepted definitions of disc degeneration are lacking, in part due to limited knowledge of the process. The measurements that are selected depend on the method used to evaluate the disc and are often qualitative ordinal rating scales, lacking in precision. Although it is generally agreed that disc degeneration is common, the prevalence of specific findings is unclear. A review of the epidemiology of disc degeneration reveals wide-ranging prevalence estimates for various signs of disc degeneration in samples of the general population and in patients with back symptoms. The extreme variations in prevalence rates are likely largely due to inconsistencies in the definitions and measurements of disc degeneration. Such inconsistencies and inaccuracies impede epidemiologic research on disc degeneration.

Determinants of the progression in lumbar degeneration: a 5-year follow-up study of adult male monozygotic twins

STUDY DESIGN

A 5-year follow-up study of exposure of discordant monozygotic twin pairs with repeated interviews and spine imaging.

OBJECTIVE

The primary goals were to record changes in the degenerative signs over a 5-year interval and to estimate the effects of familial influences and suspected environmental risk factors on the speed of lumbar degeneration.

SUMMARY OF BACKGROUND DATA

Traditionally, disc degeneration has been attributed to aging and environmental exposures; recently, a dominant effect of genetics has been revealed. Yet the etiopathogenesis of disc degeneration remains poorly understood and controversial despite being a primary target of diagnostic and therapeutic interventions.

METHODS

Among 116 monozygotic twin pairs, which had been examined 5 years earlier, 75 pairs (150 men) were reexamined. They were imaged using the same MRI scanner and examination protocol as at baseline. The data were analyzed using statistical methods for longitudinal studies.

RESULTS

Progression in disc height narrowing, disc bulging, osteophytosis, and fatty degeneration in the lumbar spine was seen in about 7% to 13% of the discs in 7% to 46% of subjects during 5-year follow-up. Few degenerative findings appear to reverse; few disc height measures increased, some anular tears were no longer visible, and bulging/herniation diminished. New anular tears (in axial view) were detected in 1.5%, disappeared in 2%, and were unchanged in 5.3% of discs; in the sagittal view, new high intensity zones findings were identified in 0.5%, were no longer apparent in 1.6%, and were unchanged in 7.1% of discs. There were no clear changes in upper endplates: in 2.1% of discs, the irregularity score increased and in 1.8% it decreased. Familial aggregation, reflecting genetic, and shared environmental influences, explained 47% to 66% of the variance in progression of degenerative signs on lumbar MRI, and resistance training and occupational physical loading together explained 2% to 10% of the progression in the degenerative signs in lumbar MRIs.

CONCLUSIONS

Progression of disc height narrowing, bulging, osteophytes, and fatty degeneration was detected in about 10% or less of the T12-S1 discs. Development and disappearance of anular lesions were rarer. No clear changes were seen in endplate irregularities. The results also confirm that hereditary effects have a dominant role in the progression of disc degeneration and suggest that occupational lifting and leisure time resistance training have modest additional effects.

Morphological studies on the ageing and osteoarthritis of the articular cartilage in C57 black mice

PURPOSE

To study the cause and mechanism of joint degeneration in osteoarthritis, through histopathological and ultrastructural-histochemical experiments on the articular cartilage of the knees of the C57 black mouse.

METHODS

192 C57 black mice and a control group of 64 C57BL/6J mice were used in this study. The left and right knee articular capsules of the joints were removed and stained. Each articular cartilage sample was examined and osteoarthritic changes were assessed using a transmission electron microscope. The severity of osteoarthritis in the knee joint cartilage of C57 black mice was histologically assessed using a classification system described by Okabe, based on Maier's system.

RESULTS

The incidence and the severity of osteoarthritis gradually increased with age; the incidence increased from 20% at 2 months to 80% at 16 months. Irreversible changes appeared at an advanced stage, and the process of degeneration was quite similar to that in human osteoarthritis. Through transmission electron microscopy, we observed poorly developed Golgi apparatus, markedly increased intracellular microfilaments, decreased proteoglycan granules, and broken collagen networks in all stages of osteoarthritis. By contrast, Golgi apparatus and other organelles were well developed in histologically normal mice of all ages. Proteoglycan granules, which mainly consisted of keratan sulphate, were observed; collagen networks were maintained.

CONCLUSION

Disturbed protein transport and sugar synthesis in chondrocytes, caused by the deficient development of the Golgi apparatus, could result in degenerative changes in articular cartilage. The structure and function of the matrix were maintained mainly because of the continued presence of keratan sulphate.

Lumbar disc degeneration: epidemiology and genetic influences

STUDY DESIGN

A literature review.

OBJECTIVE

To synthesize the scientific literature on the prevalence of lumbar disc degeneration and factors associated with its occurrence, including genetic influences.

METHODS

A literature review was conducted of the prevalence of disc degeneration. Studies of the etiology of disc degeneration were summarized, with particular attention given to studies of genetic influences.

RESULTS AND CONCLUSIONS

There are extreme variations in the reported prevalence of specific degenerative findings of the lumbar spine among studies, which cannot be explained entirely by age or other identifiable risk factors (e.g., prevalence figures for disc narrowing varied from 3% to 56%). It is likely that these variations are due, in great part, to inconsistencies in case definitions and measurements, which are impeding epidemiologic research on disc degeneration. Research conducted over the past decade has led to a dramatic shift in the understanding of disc degeneration and its etiology. Previously, heavy physical loading was the main suspected risk factor for disc degeneration. However, results of exposure-discordant monozygotic and classic twin studies suggest that physical loading specific to occupation and sport has a relatively minor role in disc degeneration, beyond that of upright postures and routine activities of daily living. Recent research indicates that heredity has a dominant role in disc degeneration, explaining 74% of the variance in adult populations studied to date. Since 1998, genetic influences have been confirmed by the identification of several gene forms associated with disc degeneration.

Is the incidence of elbow osteoarthritis underestimated? Insights from paleopathology

OBJECTIVES

Osteoarthritis is uncommon at the elbow in contemporary populations. We sought to determine whether this was also the case in medieval and premodern times.

MATERIAL AND METHODS

Standard criteria for osteoarthritis were applied to 496 complete elbows from a necropolis in Provence, France.

RESULTS

Osteoarthritis was found in 27% of elbows. Significant differences were noted across periods and age groups but not between the right and left sides.

CONCLUSION

Our data suggest that the symptoms of elbow osteoarthritis may be far milder than expected from the underlying pathological lesions. The incidence of elbow osteoarthritis in contemporary populations is probably underestimated. The high prevalence of elbow osteoarthritis in archeological populations cannot be taken as a marker for activities placing stress on the upper limbs.

Is osteoarthritis a systemic disorder of bone?

OBJECTIVE

To describe the osteologic findings associated with osteoarthritis (OA) of a variety of joints.

METHODS

We performed visual examination of 563 skeletons of which >/=80% of the skeleton was available, from an archaeologic site in England. The surfaces and margins of several different joints (shoulders, elbows, wrists, hips, hands, knees, and ankles) were studied for evidence of eburnation and osteophytes, respectively, and the entire skeleton was examined for evidence of generalized enthesophyte formation. Associations between changes in different joint sites and between enthesophyte formation and evidence of OA were sought.

RESULTS

Eburnation and osteophyte formation at the hand, hip, and knee were strongly associated with eburnation and osteophytes at other joint sites not commonly thought to be prone to OA, including the elbow and wrist. Only the ankle was rarely involved. There was also a strong relationship between both bone eburnation and osteophytes and generalized enthesophyte formation. These findings remained statistically significant after adjustment for the age, sex, and historical period of the skeletons.

CONCLUSION

Our findings indicate that skeletal OA is more widespread in the body than is apparent from clinical studies and are consistent with other data suggesting that OA is a disease that is primarily dependent on systemic predisposition to a particular type of bone response to mechanical stress.

Glenoid osteophyte and rotator cuff tears: an anatomic study

The purpose of this study was to determine the morphologic characteristics of the glenoid osteophyte and its relationship to rotator cuff tears. Eighty-six cadaveric shoulders were studied. After inspection of cuff pathology, the glenoid was examined with soft x-rays. Histologically, degenerative changes of the articular cartilage and the labrum were assessed. There were 30 shoulders with rotator cuff tears (35%). Two types of glenoid osteophyte were identified: angular and hooked. Both osteophytes were commonly observed in the anterior to inferior portions of the glenoid. The length of hooked osteophytes was significantly greater in shoulders with full-thickness tears (2.7 +/- 2.2 mm [mean plus minus SD]) than in those with other cuff conditions (P =.0058). The hooked osteophyte was more commonly observed in shoulders with full-thickness tears (43%) and associated with degenerative changes of the cartilage and labrum. We conclude that the hooked osteophyte of the glenoid is characteristic in shoulders with full-thickness tears of the rotator cuff.

Functional adaptation of human joints to mechanical stimuli

OBJECTIVE

This study tests the hypothesis that functional adaptation occurs in human joints, and that substantial differences in joint 'loading history' explain the phenotypic variability observed in human cartilage morphology.

METHOD

We examined 18 triathletes (nine men and nine women) who had been physically active throughout life (training for >10 h per week for the last 3 years), and 18 volunteers that had never been physically active on a regular basis. The right knee joints were imaged with a previously validated fat-suppressed gradient-echo MR sequence. Cartilage volume, thickness, joint surface areas, and normalized cartilage signal intensity were determined with post-processing software, specifically designed for these applications.

RESULTS

The knee joint cartilage thickness, and signal intensity were not significantly different between athletes and inactive volunteers, but male athletes displayed significantly larger knee joint surfaces (P< 0.01; +8.8%). Female athletes displayed a significantly larger medial tibia (P< 0.05; +18.9%), the difference in the total knee surface area reaching borderline significance (P=0.08; +7.0%).

CONCLUSIONS

The results suggest that joint size can be modulated during growth, but that (opposite to muscle and bone) the thickness of the cartilage does not adapt to mechanical stimulation. This finding may reveal a general principle in the development and functional adaptation of diarthrodial joints, elucidating an important mechanism for reducing mechanical stress in biphasic cartilage layers.

Cervical myelopathy caused by C3-C4 spondylosis in elderly patients: a radiographic analysis of pathogenesis

STUDY DESIGN

A radiographic analysis of elderly patients with cervical spondylotic myelopathy, particularly those with involvement of the C3-C4 level.

OBJECTIVES

To elucidate the potential contributors to the higher incidence of pathology at C3-C4 in the elderly.

SUMMARY OF BACKGROUND DATA

In this study, the elder patients showed a greater predilection for involvement of the C3-C4 lesion compared with their younger counterparts. No previous study has addressed C3-C4 pathology in elderly patients.

METHODS

This study included 18 patients, 10 men and 8 women, with cervical spondylotic myelopathy caused by C3-C4 disorders (group I). For the purpose of comparison, 18 younger patients (less than 50 years of age) with myelopathy (group II) and 30 volunteers over the age of 65 (group III) were also investigated. Mean age at admission was 73.5 years for group I, 42.4 years for group II, and 73.4 years for group III. Radiographic analysis, using static and dynamic radiographs, was performed to evaluate the morphologic features.

RESULTS

The mean spinal canal diameter for groups I and II was significantly smaller than that for group III. Group I exhibited greater C2-C7 lordosis. The aged population, group I and group III, showed greater C3-C4 angulation associated with C4 forward inclination in neutral standing position as compared with younger patients. Regarding dynamic factors, group I showed the largest segmental motion at C3-C4, and, conversely, the smallest mobility at the lower segments, with significant differences.

CONCLUSIONS

Using radiographic analysis, morphologic features that predispose patients to disorders of the C3-C4 motion segment were evaluated. These features included 1) greater C3-C4 angulation associated with age-related postural change and 2) hypermobility at the C3-C4 segment compensating for decreased mobility at the lower segments.

The relationship between articular cartilage degeneration and bone changes of the first metatarsophalangeal joint

Plain-film radiography is commonly used in the assessment of joints affected by osteoarthritis. It has been shown that the condition of articular cartilage in the knee, when grossly assessed, does not always correlate well to the radiographic evaluation of the joint. The aim of this study was to determine whether a relationship existed between the radiographic appearance of the subchondral bone and the morphological condition of the articular cartilage surfaces of the first metatarsophalangeal joint. Forty-nine pairs of cadaveric metatarsals and their respective proximal phalanges were studied in order to determine the correlation between articular cartilage degeneration and radiographic grade using a modified Kellgren-Lawrence scale. The relationship between cartilage degeneration and age, gender, osteophytes, metatarsal length, and measured angles (proximal articular set angle, distal articular set angle, intermetatarsal angle) was also investigated. It was found that there was a significant correlation between radiographic grade and cartilage degeneration on both the metatarsal head and the base of the proximal phalange (r2 = .2038 and .1733, respectively). However, while useful in the clinical setting, bony changes of the first metatarsophalangeal joint, as seen radiographically, fail to provide a full representation of the level of cartilage degeneration on the articular surfaces of this joint.

The influence of occupation on lumbar degeneration

In many countries, back problems have been defined as occupational injuries. The belief underlying this injury model is that back symptoms are caused primarily by work-related mechanical factors that damage the structures of the spine, either through a single incident or repeated loading. Although the etiopathogenesis of degenerative findings in the disc and their relation to pain are poorly understood, changes in the disc are suspected of underlying many back symptoms. The focus of this article is on examining the relation between occupational factors and disc degeneration. Occupational factors suspected of accelerating spinal degeneration include accident-related trauma; heavy physical loading and materials handling, including lifting, bending, and twisting; prolonged sitting; and sustained nonneutral work postures and vehicular driving. There is evidence to suggest that occupational exposures have an effect on disc degeneration. However, these factors explain little of the variability in degeneration found in the adult population. Furthermore, the lack of a clear dose-response relation between time spent in various occupational loading conditions and degenerative findings adds to doubts about a strong causal link. The contribution of suspected occupational risk factors appears to be particularly modest when compared with familial influences, which reflect the combined effects of genes and early childhood environment. These findings challenge the dominant role assumed for occupational loading in disc degeneration and associated back problems, and suggest a more complex etiology.

Assessment of cancellous bone quality in severe osteoarthrosis: bone mineral density, mechanics, and microdamage

The role of bone microdamage (microscopic cracks or microcracks and ultrastructural collagen matrix and bone mineral damage) in diseases such as osteoarthrosis and osteoporosis is poorly understood. Microdamage accumulation in vivo is influenced by age and cyclic loading, therefore, it would be useful if the burden of microdamage in bone could be assessed by noninvasive measures such as the radiological measurement of bone mineral density (BMD). The aim of this study was to investigate the relationship between BMD, compressive strength and stiffness, and microdamage in the cancellous bone of the proximal femur in patients with severe osteoarthrosis. Trabecular bone core samples, from the intertrochanteric region of the femur, were obtained from 34 patients, with a mean age of 70.3 +/- 11.1 years, undergoing total hip arthroplasty for osteoarthrosis. Cores selected from contact X-ray images were used for BMD measurement, compressive mechanical testing or left untested (uncrushed), en bloc staining for microdamage, and bone histomorphometry. The study shows a strong dependence of both the elastic modulus and ultimate failure stress of the bone samples on BMD and a significant relationship between the elastic modulus and trabecular anisotropy (Tr. An). In multiple linear regression, BMD and Tr. An together account for about 70% of the variance in the elastic modulus. Then including microcrack crack density (Cr.Dn) and damage volume fraction (DxV/BV) variables, Tr. An alone accounts for a relatively small amount of the variation (8.5%) in ultimate failure stress and elastic modulus. The Cr.Dn accounts for more of the variation in the ultimate failure stress than in the elastic modulus (50% vs. 7%). In this experiment, data for Cr.Dn provide a measure of damage associated with the ultimate failure of cancellous bone. In specimens that were not mechanically tested, in vivo microcrack accumulation increases exponentially with age. In conclusion, data from this study suggest that BMD and Cr.Dn are the major determinants of cancellous bone strength, whereas BMD and Tr. An are major determinants of cancellous bone stiffness. In bone specimens subjected to compressive testing there was no relationship between microdamage and BMD, suggesting that BMD cannot be used to monitor changes in the mechanical properties of bone due to microdamage accumulation.

Generation II knee bracing for severe medial compartment osteoarthritis of the knee

OBJECTIVE

To investigate the clinical efficacy of the Generation II (G II) knee brace, a newly developed knee orthosis, on patients experiencing severe medial compartment osteoarthritis (OA) of the knee.

DESIGN

Case series.

SETTING

A national medical and pharmaceutical hospital in Japan.

PATIENTS

Twenty primary OA subjects (excluding those with secondary OA), all older than 55 years of age and experiencing only knee joint problems, were selected according to their ability to walk more than 500 meters independent of support. These patients had arthritis in both knees and no less than one half of normal joint space remaining as revealed by roentgenogram studies. The more severely affected side was selected for bracing.

INTERVENTIONS

For 12 months, each patient wore a G II knee brace on the affected knee on a daily basis, removing it only at night. To evaluate the effects of G II OA brace alone, additional use of new oral drugs or any other treatment was prohibited from 1 month before application of the G II OA brace and throughout the trial period.

MAIN OUTCOME MEASURES

Clinical efficacy was evaluated using the Japan Orthopaedic Association's knee scoring system. X-ray evaluation was performed with patients standing on one leg. A dynamometer was used to evaluate isokinetic quadriceps muscle strength. The center of gravity was measured using an X-Y recording. Clinical evaluation was performed every 2 months thereafter. Final evaluation was at 12 months.

RESULTS

Nineteen of the 20 patients answered that they experienced significant pain relief. Knee pain scores on walking increased from 18.0 to 21.5 and on ascending and descending stairs increased from 12.8 to 15.8. The femorotibial angle decreased in 12 of the patients, and the mean angle decreased from 185.1 degrees before application to 183.7 degrees with the brace on at the final observation period. In addition, isokinetic quadriceps muscle strength increased from an average of 36.8 Nm to 42.8 Nm for all patients. In 17 patients, quadriceps muscle strength increased, while it decreased in 2 and remained the same in 1. Finally, lateral movement of the center of gravity decreased compared with before G II application in all patients.

CONCLUSION

G II bracing is a beneficial treatment for severe medial OA of the knee.

Osteoarthritis in ankle and knee joints

Ankle and knee joints differ in their susceptibility to osteoarthritis (OA). This article reviews literature on differences between these joints. A Medline search and search of bibliographies of review articles was conducted. Knee cartilage degeneration leads to the development of OA with clinical symptoms, whereas the ankle cartilage develops fissures that do not appear to progress to later stages of OA. Epidemiological studies support these findings. Factors that might explain this phenomena include differences in joint motion, cartilage thickness, congruency, mechanical forces, and even evolutionary changes. Data suggest that chondrocytes from the two joints may respond differently to stimuli. Comparisons of cartilage from the knee and ankle joint of the same donor may provide a better understanding of the biochemical and molecular processes that induce the pathogenesis of OA and may provide new approaches to early detection and treatment.

Prevalence of degenerative morphological changes in the joints of the lower extremity

Information on the prevalence and extent of degenerative morphological changes (DMC) in the joints of the lower extremity, including foot joints is sparse. In the present study, the first and fifth metatarsalphalangeal (MTP), transverse tarsal, subtalar, talocrural, knee and hip joints of 50 cadavers were examined grossly and graded on a five-point scale for signs of DMC. Selected samples were examined histologically. Our results confirm clinical findings that severe DMC in foot joints are uncommon except in the first MTP joint where the plantar aspect is most affected. The knee joint displayed the most numerous and severe signs of DMC followed by the first MTP joint. The hip, talocrural, subtalar and transverse tarsal joints displayed comparatively moderate levels of DMC while the fifth MTP was rarely affected. The only joint to display significantly greater levels of DMC on the distal side of the joint as compared with the proximal side, when a difference was present, was the hip. There were significantly greater levels of DMC on the medial aspect of two or more joints within an extremity than on the lateral aspect. Radiographs often showed few or no signs of DMC even when erosion down to subchondral bone was observed upon gross examination.

Elbow joint disorders in relation to vibration exposure and age in stone quarry workers

Elbow joint disorders were studied in relation to vibration exposure and age in 74 male stone quarry workers who operated mainly chipping hammers and sometimes rock drills. They were examined for range of active motion in elbow extension and flexion, and by means of radiographs of the elbow joint. Effects of age and vibratory tool operation on the elbow joint were statistically estimated using multiple regression analysis. In the analysis of all subjects, including those aged over 60 years, age was significantly related to the range of motion in extension and to radiographic changes in both elbows, and the duration of vibratory tool operation was associated with the range of right elbow flexion. Among subjects under the age of 60 years, duration of vibratory tool operation showed a significant dose-effect relationship to the range of flexion and radiographic changes in the right elbow, but there was no significant relationship with age. The present results suggest that the operation of chipping hammers and rock drills contributes to elbow joint disorders or osteoarthrosis, even when the effect of age is taken into account. Besides vibration exposure, it may be necessary to consider various loads on the elbow joint such as firmly grasping and pressing the tool against stones with the arm bent at about 90 degrees, and carrying stones.

Relationship between the utilisation profile of individual joints and their susceptibility to primary osteoarthritis

Two subjects were studied for 1 to 3 weeks during the course of their normal domestic activities. Utilisation profiles were derived for ten joints, using a systematic time-series sampling technique adapted from behavioural biology. At each joint the proportion of the available range utilised was noted. The results were compared with the known regional prevalence of primary osteoarthritis. There was a correlation between the degree to which a joint was incompletely utilised, and its susceptibility to osteoarthritis. The hypothesis is advanced that primary osteoarthritis may be due to incomplete joint utilisation.

Anterior knee pain

Anterior knee pain is a common symptom, especially in adolescence, and often no specific cause is sought or identified. Physicians who treat patients with knee pain should understand the normal anatomic features and the biomechanics of the patellofemoral joint. We review this information and discuss important aspects of the physical examination and roentgenographic evaluation in patients with anterior knee pain. Once the clinical cause of anterior knee pain has been established, directed nonoperative treatment including physical therapy should be initiated. Surgical intervention is generally reserved for patients in whom nonoperative management is unsuccessful and identifiable abnormalities exist.

Generalised osteoarthritis: an evolutionary problem?

Polyarticular osteoarthritis (OA) has a distinctive pattern of joint involvement. Some joints, such as the first metatarsophalangeal joint, are commonly affected, whereas others, such as the shoulder, are rarely involved. This distinct pattern of involvement may represent a subset of OA--generalised OA. Analysis of the pattern of change in joint function in the recent evolutionary development of man suggests a hypothesis that explains the pattern of joint involvement in generalised OA. Joints most commonly affected have undergone recent rapid evolutionary change to a new function that has resulted in increased loading. These joints are therefore relatively underdesigned, have little functional reserve, and are likely to fail often and early. Joints that are rarely affected have changed to a function with reduced loading. They are relatively overdesigned and have a large functional reserve, so fail rarely and late.

Osteoarthrosis: sex-specific relationship to osteoporosis

Examination of an Eskimo skeletal series demonstrated at least two etiologically distinct groups of joint deterioration divided along sex lines. Low bone mineral content (BMC) among women and high BMC among men were associated with osteoarthrosis on the tibial plateau. This finding contradicts conventional wisdom based on clinical observation, which suggests that reduced skeletal mass prevents osteoarthrosis.

Joint space in normal gleno-humeral radiographs

The gleno-humeral joint space in standard antero-posterior images of 175 normal subjects was measured at three different sites. The average of the three measurements, the integral joint space, was calculated and was found to be between 4 and 5 mm. The value does not change with age, except in women, in whom it increases slightly. A narrow joint space in an elderly patient should not be expected simply because the patient is old. The measuring technique described is useful in population studies. In individual cases a simple measurement with a ruler serves the same purpose.

Degeneration of the gleno-humeral joint. An anatomical study

One hundred and fifty-one shoulder dissections were performed on 76 cadavera, 41 men and 35 women, with an average age of 68 (range 18-92). Before the age of 60 no degenerative changes were encountered but after 60, degeneration and full thickness ruptures of the rotator cuff, cartilage degeneration and degeneration and ruptures of the long biceps tendon appeared in an increasing frequency with age. A highly significant relationship between cuff degeneration and cartilage degeneration was found. Measurement of the thickness of normal joint cartilage of the caput humeri did not show any changes with time. Gleno-humeral degeneration was encountered bilaterally in 82 per cent and was more frequent in women, and there is little evidence that occupation is of major importance for the development of shoulder joint degeneration.

The pattern of involvement of appendicular degenerative joint disease

Patterns of degenerative joint disease are investigated in the shoulder, elbow, hip, and knee joints of the macerated remains of approximately 800 individuals from 20th century American and two prehistoric populations. Age is an important contributory factor in all joints, but its effects are seen most directly in the shoulder and hip. Patterns of right-left involvement also indicate the elbow is the most susceptible area to local factors. Multiple joint involvement is seen more often in females from contemporary populations but more often in males from archeological groups. No significant association is found between degenerative involvement and osteometric measurements, and cause of death is probably only incidentally associated with degenerative disease.

Stress and the etiology of osteoarthritis

Although degenerative joint disease is an old and exceedingly common problem, clinical investigators have not reached a consensus regarding the etiology of this disease. Comparative osteological analysis of the knee, hip, shoulder, and elbow joints of 789 individuals from four human skeletal populations (Black and White Americans, Pueblo Indians, and Alaskan Eskimos) indicates that age of onset, frequency, and location of degenerative changes are directly related to the nature and degree of environmentally associated stress, as reflected by the variable life styles of the populations sampled. Eskimos have the earliest onset and most severe involvement for all four joints studied, the right side is usually more affected than the left, and Blacks are more frequently involved than Whites in the knee, shoulder, and elbow. Functional stress, when constant and severe in nature, becomes the primary focus of degenerative disease, but other background contributing agents such as age, sex, and hormonal influence must not be ignored.

Degenerative disease in the temporomandibular, metatarsophalangeal and sternoclavicular joints. An autopsy study

The right temporomandibular, sternoclavicular and first metatarsophalangeal joints were removed post mortem from 39 subjects. The surfaces of the various parts of the joints were examined and evaluated according to a grading system. Repeated evaluation of the joints showed a good reproducibility of the grading system. Of the 33 temporomandibular joints, 12 showed deviations in shape. Degenerative disease was uncommon and seen in only 3 joints. The total "score for degeneration" showed only a weak correlation with age (r = 0.28, rs = 0.08). Degenerative disease was common in the 35 sternoclavicular joints. All joints except 7 showed degenerative changes. A moderate correlation was found between age and the score for degeneration (r = 0.58). Of the 39 metatarsophalangeal joints only 5 were allotted no points of degeneration. A moderate correlation was found between age and score for degeneration (r = 0.61). No significant differences of degeneration were found between sexes. The coefficient of correlation between the score for degenerative disease of the temporomandibular joint and the degeneration score for the sternoclavicular joint and the toe-joint were r = 0.22 (rs = 0.16) and r = 0.46 (rs = 0.44), respectively. The significant association of degenerative disease found between the toe-joint and the sternoclavicular joint (r = 0.54, rs = 0.54) was reduced (to r = 0.29) when age-dependence was excluded. The degenerative changes described in this material are probably mostly due to local factors.

Chondromalacia of the patella. Incidence, macroscopical and radiographical findings at autopsy

In a post-mortem series of 59 persons aged 10-50 years, 91 of the 118 patellae exhibited cartilaginous changes. These changes were most common in the older age groups and usually affected the medial articular facet where they were also most extensive and most profound. Clinical and radiological assessment showed this facet to be less suited to articulation with the femur because of its convex joint surface, central ridges, and prominences. Radiography using tangential views of the entire patella and of 2 mm thick slices of the patella showed in cases with macroscopically normal cartilage a less dense bony structure medially and a denser structure laterally. Even in the presence of distinct cartilaginous changes this difference in bone density did not alter essentially. In particular, there was no definite sclerosing medially, where the changes in the cartilage were most marked. Osteophyte formation was sparse, but most common in the older age groups, and laterally. Osteophytes were seen only on patellae with cartilaginous changes.

Chondromalacia of the patella. Physical signs in relation to operative findings

Cartilaginous changes on the patella are common and were demonstrated in 50 out of 100 patients who underwent operation for intraarticular disease of the knee joint. In order to clarify further the signs of this condition, the physical signs were related to the operative findings. Retropatellar crepitation was present in most cases, but cannot be called pathognomonic. Pain on grating and tenderness on palpation of the patella in fact occurred together only in cases with cartilaginous changes on the patella. On the other hand, cartilaginous changes were found in several cases without such signs, a condition which perhaps should be interpreted as cartilaginous changes only, not as the symptom complex chondromalacia of the patella in which there ought to be a history of symptoms.