Association of radiographic features of osteoarthritis of the knee with knee pain: data from the Baltimore Longitudinal Study of Aging

An ultrasonographic study of metatarsophalangeal joint pain: synovitis, structural pathology and their relationship to symptoms and function

BACKGROUND

Pain in the first metatarsophalangeal joint (MTPJ) is common, though the link between pathology and symptoms is poorly understood.

OBJECTIVES

To examine the relationship between pain, function and ultrasound (US)-detected pathology in the first MTPJ.

METHODS

33 subjects with first MTPJ pain and 20 asymptomatic controls completed questionnaires about pain and function, then underwent clinical examination, US examination and objective assessment of function using a motion tracking system.

RESULTS

Low-level grey scale synovitis and osteophytes were common in patients and controls. Osteophytes were more prevalent in symptomatic first MTPJ [24/33 (73%) vs. 7/20 (35%), p=0.007], and greater osteophyte numbers were weakly associated with higher levels of pain [increase in pain VAS per osteophyte (95% CI)=13.78mm (0.12mm-27.43mm), p=0.048]. A power Doppler (PD) signal was present in a fifth of painful first MTPJs and absent in controls. A PD signal was associated with osteophytes and joint space narrowing but was not independently related to target joint pain. For all first MTPJs, osteophytes and the presence of a PD signal was associated with worse patient-reported function. US features did not predict objective function.

CONCLUSION

Osteophytes, representing subchondral bone remodelling, were associated with the presence of first MTPJ pain and, together with more severe (PD) synovitis, also contributed to poorer function. Detailed imaging of bone may provide more information on peripheral pain associations.

Is radiology a determinant of pain, stiffness, and functional disability in knee osteoarthritis? A cross-sectional study

BACKGROUND AND PURPOSES

Discordance between clinical and radiological profiles in knee osteoarthritis has been reported. We hypothesized that the discordance could be due to limited radiological variables studied. This study essentially analyzed many more radiological features than previous studies in order to seek an association between clinical and radiographic features.

METHODS

One hundred and eighty patients with knee osteoarthritis were enrolled as per the American College of Rheumatology (ACR) guidelines. Visual analog scale (VAS) for knee pain and the knee-specific Western Ontario Mac University (WOMAC) index for pain, stiffness, and disability were recorded. Five additional radiological features apart from those in the Kellgren-Lawrence (KL) classification grading system were recorded by two authors who were blinded to the clinical diagnosis. The variables significantly associated were analyzed by linear regression model.

RESULTS

Pain was significantly associated with increasing KL grades; physical function was nearly significant and stiffness was not. On analysis of individual radiological features, WOMAC pain was significant with subchondral sclerosis, joint space width, and tibiofemoral alignment although the correlation was week. VAS pain was significant with the latter two and with articular incongruity. Functional disability was associated with medial joint-space narrowing, tibiofemoral alignment, loose bodies, and juxta-articular osteopenia. However, in the linear regression model, pain and stiffness were significantly associated with articular incongruity and functional disability and total clinical scores with juxta-articular osteopenia.

CONCLUSION

When the radiological features were extended beyond those included in KL grades, pain, stiffness, and disability correlated well with radiography; articular incongruity with pain and stiffness; and juxta-articular osteopenia with physical disability and clinical severity.

The relationship between body mass index across the life course and knee pain in adulthood: results from the 1958 birth cohort study

OBJECTIVES

To determine whether a high BMI in childhood or early adulthood has a long-term influence on the likelihood of knee pain.

METHODS

A birth cohort study of persons born during first week of 1958 in Great Britain. Participants were followed up throughout childhood and adulthood, most recently at 45 years, when information was collected on knee pain. Information on BMI was collected at follow-up intervals throughout childhood and adulthood. RESULTS; A total of 8579 individuals participated and the prevalence of being overweight and obesity increased throughout life from 0.2% at the age of 7 years to 65.5% at the age of 45 years. A total of 1636 individuals reported knee pain at the age of 45 years, giving a prevalence of 19.1% (95% CI 18.2, 19.9%). BMI was associated with knee pain: persons with a BMI of >30 kg/m(2) at 23, 33 or 45 years experienced approximately a doubling in the risk of knee pain at 45 years. There was a significant association with knee pain at the age of 45 years with high BMI from as early as age 11 years, but the association was stronger at the age of 16 years [relative risk (RR)(BMI 20-25) (v)(s) (<20) = 1.2 (95% CI 1.1, 1.3); RR(25-30) = 1.3 (95% CI 1.1, 1.6); RR(>30) = 1.6 (95% CI 1.05, 2.4)].

CONCLUSION

This study has demonstrated the long-term effects of childhood and early adult obesity and the importance of early intervention programmes to try to reduce weight and maintain weight loss.

The Ile585Val TRPV1 variant is involved in risk of painful knee osteoarthritis

OBJECTIVE

To assess if a coding variant in the gene encoding transient receptor potential cation channel, subfamily V, member 1 (TRPV1) is associated with genetic risk of painful knee osteoarthritis (OA).

METHODS

The Ile585Val TRPV1 variant encoded by rs8065080 was genotyped in 3270 cases of symptomatic knee OA, 1098 cases of asymptomatic knee OA and 3852 controls from seven cohorts from the UK, the USA and Australia. The genetic association between the low-pain genotype Ile-Ile and risk of symptomatic and asymptomatic knee OA was assessed.

RESULTS

The TRPV1 585 Ile-Ile genotype, reported to be associated with lower thermal pain sensitivity, was associated with a lower risk of symptomatic knee OA in a comparison of symptomatic cases with healthy controls, with an odds ratio (OR) of 0.75 (95% CI 0.64 to 0.88; p=0.00039 by meta-analysis) after adjustment for age, sex and body mass index. No difference was seen between asymptomatic OA cases and controls (OR=1.02, 95% CI 0.82 to 1.27 p=0.86) but the Ile-Ile genotype was associated with lower risk of symptomatic versus asymptomatic knee OA adjusting for covariates and radiographic severity (OR=0.73, 95% CI 0.57 to 0.94 p=0.0136). TRPV1 expression in articular cartilage was increased by inflammatory cytokines (tumour necrosis factor α and interleukin 1). However, there were no differences in TRPV1 expression in healthy and arthritic synovial tissue.

CONCLUSIONS

A genotype involved in lower peripheral pain sensitivity is significantly associated with a decreased risk of painful knee OA. This indicates a role for the pro-nociceptive gene TRPV1 in genetic susceptibility to symptomatic knee OA, which may also be influenced by a role for this molecule in cartilage function.

Subgroups of older adults with osteoarthritis based upon differing comorbid symptom presentations and potential underlying pain mechanisms

Introduction

Although people with knee and hip osteoarthritis (OA) seek treatment because of pain, many of these individuals have commonly co-occurring symptoms (for example, fatigue, sleep problems, mood disorders). The purpose of this study was to characterize adults with OA by identifying subgroups with the above comorbid symptoms along with illness burden (a composite measure of somatic symptoms) to begin to examine whether subsets may have differing underlying pain mechanisms.

Methods

Community-living older adults with symptomatic knee and hip OA (n = 129) participated (68% with knee OA, 38% with hip OA). Hierarchical agglomerative cluster analysis was used. To determine the relative contribution of each variable in a cluster, multivariate analysis of variance was used.

Results

We found three clusters. Cluster 1 (n = 45) had high levels of pain, fatigue, sleep problems, and mood disturbances. Cluster 2 (n = 38) had intermediate degrees of depression and fatigue, but low pain and good sleep. Cluster 3 (n = 42) had the lowest levels of pain, fatigue, and depression, but worse sleep quality than Cluster 2.

Conclusions

In adults with symptomatic OA, three distinct subgroups were identified. Although replication is needed, many individuals with OA had symptoms other than joint pain and some (such as those in Cluster 1) may have relatively stronger central nervous system (CNS) contributions to their symptoms. For such individuals, therapies may need to include centrally-acting components in addition to traditional peripheral approaches.

Relationship between radiological severity and clinical and psychological factors in knee osteoarthritis

This study was designed to investigate the relationship between radiological severity and clinical and psychological factors in patients with knee osteoarthritis (OA). Patients with knee OA (n = 100) were included in the study. Radiographic staging was done using Kellgren-Lawrence (KL) radiological rating scale. Stage 1-2 changes according to KL were grouped as 'early' and stage 3-4 as 'late' radiological OA. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was used for self-reported disability. Performance-based functional assessments were measured as time needed to walk 15 m and time needed to climb ten steps. Health-related quality of life was assessed by Nottingham Health Profile (NHP). Beck Depression Inventory (BDI) was used to assess the presence and severity of depression. Social isolation was assessed by a related NHP subscale. Significantly higher scores were found in the late stage group for NHP pain, physical mobility and social isolation subscales and all WOMAC subscales. Mean BDI score was significantly higher (p = 0.001) and performance-based functional score was significantly worse (p < 0.001) in the late stage group compared to the early stage. In logistic regression analysis, NHP social isolation subscore was found to be associated with WOMAC pain subscore (p = 0.013, odds ratio [OR] = 1.163; 95% confidence interval [CI], 1.032-1.309) and radiological severity (p = 0.018, OR = 2.924; 95% CI, 1.198-7.136). Radiological severity is an important indicative factor for pain, disability, depression and social isolation. We believe that assessment of psychological involvement in addition to pain and disability might provide benefit in the management of patients with advanced radiological knee OA.

The role of pain and functional impairment in the decision to recommend total joint replacement in hip and knee osteoarthritis: an international cross-sectional study of 1909 patients. Report of the OARSI-OMERACT Task Force on total joint replacement

OBJECTIVE

To assess the pain and functional disability levels corresponding to an indication for total joint replacement (TJR) in hip and knee osteoarthritis (OA).

DESIGN

International cross-sectional study in 10 countries.

PATIENTS

Consecutive outpatients with definite hip or knee OA attending an orthopaedic outpatient clinic. Gold standard measure for recommendation for TJR: Surgeon's decision that TJR is justified.

OUTCOME MEASURES

Pain (ICOAP: intermittent and constant osteoarthritis pain, 0-100) and functional impairment (HOOS-PS/KOOS-PS: Hip/Knee injury and Osteoarthritis Outcome Score Physical function Short-form, 0-100).

ANALYSES

Comparison of patients with vs without surgeons' indication for TJR. Receiver Operating Characteristic (ROC) curve analyses and logistic regression were applied to determine cut points of pain and disability defining recommendation for TJR.

RESULTS

In all, 1909 patients were included (1130 knee/779 hip OA). Mean age was 66.4 [standard deviation (SD) 10.9] years, 58.1% were women; 628/1130 (55.6%) knee OA and 574/779 (73.7%) hip OA patients were recommended for TJR. Although patients recommended for TJR (yes vs no) had worse symptom levels [pain, 55.5 (95% confidence interval 54.2, 56.8) vs. 44.9 (43.2, 46.6), and functional impairment, 59.8 (58.7, 60.9) vs. 50.9 (49.3, 52.4), respectively, both P<0.0001], there was substantial overlap in symptom levels between groups, even when adjusting for radiographic joint status. Thus, it was not possible to determine cut points for pain and function defining 'requirement for TJR'.

CONCLUSION

Although symptom levels were higher in patients recommended for TJR, pain and functional disability alone did not discriminate between those who were and were not considered to need TJR by the orthopaedic surgeon.

A systematic review of clinical outcomes in patients undergoing meniscectomy

Knee meniscectomy is the most common procedure performed by orthopaedic surgeons. While it is generally believed that loss of meniscal tissue leads to osteoarthritis and poor knee function, many variables may significantly influence this outcome. Through literature search engines including PubMed and Ovid, 4 randomized controlled trials, 2 prospective cohorts, and 23 retrospective cohorts that fit the criteria for level I, II, and III level of evidence were included in this systematic review. For the level III evidence studies, follow-up of 5 years or more was required. Preoperative and intraoperative predictors of poor clinical or radiographic outcomes included total meniscectomy or removal of the peripheral meniscal rim, lateral meniscectomy, degenerative meniscal tears, presence of chondral damage, presence of hand osteoarthritis suggestive of genetic predisposition, and increased body mass index. Variables that were not predictive of outcome or were inconclusive or had mixed results included meniscal tear pattern, age, mechanical alignment, sex of patient, activity level, and meniscal tears associated with anterior cruciate ligament (ACL) reconstruction. While an intact meniscus or meniscal repair was generally favorable in the ACL-reconstructed knees, meniscal repair of degenerative meniscal tissue was not favorable. There is a lack of uniformity in the literature on this subject with a preponderance of lower level evidence. Although randomized controlled trials are considered to be the gold standard in medical research, a multicenter prospective cohort design may be more appropriate in assessing the long-term outcome of meniscal surgery and the role that multiple preoperative and intraoperative variables may play in clinical outcomes. In addition, future studies should include factors not assessed or adequately evaluated by several of the included studies, such as meniscal tear pattern, age, mechanical alignment, sex of the patient, activity level, meniscal tears associated with other injuries such as the ACL, smoking, and the effect of previous surgery.

Changes in Abeta non-nociceptive primary sensory neurons in a rat model of osteoarthritis pain

Background

Pain is a major debilitating factor in osteoarthritis (OA), yet few mechanism-based therapies are available. To address the need to understand underlying mechanisms the aim of the present study was to determine changes in sensory neurons in an animal model of OA pain.

Results

The model displayed typical osteoarthritis pathology characterized by cartilage degeneration in the knee joint and also manifested knee pathophysiology (edema and increased vasculature permeability of the joint) and altered nociception of the affected limb (hind paw tenderness and knee articulation-evoked reduction in the tail flick latency). Neurons included in this report innervated regions throughout the entire hind limb. Aβ-fiber low threshold mechanoreceptors exhibited a slowing of the dynamics of action potential (AP) genesis, including wider AP duration and slower maximum rising rate, and muscle spindle neurons were the most affected subgroup. Only minor AP configuration changes were observed in either C- or Aδ-fiber nociceptors.

Conclusion

Thus, at one month after induction of the OA model Aβ-fiber low threshold mechanoreceptors but not C- or Aδ-fiber nociceptors had undergone changes in electrophysiological properties. If these changes reflect a change in functional role of these neurons in primary afferent sensory processing, then Aβ-fiber non-nociceptive primary sensory neurons may be involved in the pathogenesis of OA pain. Further, it is important to point out that the patterns of the changes we observed are consistent with observations in models of peripheral neuropathy but not models of peripheral inflammation.

Effects of a metalloproteinase inhibitor on osteochondral angiogenesis, chondropathy and pain behavior in a rat model of osteoarthritis

OBJECTIVE

To investigate the effects of a matrix metalloproteinase (MMP) inhibitor on joint pathology and pain behavior in the rat meniscal transection (MNX) model of osteoarthritis (OA) and evaluate which aspects of structural disease modification contribute to symptom improvement.

METHODS

OA pathology was induced in male Lewis rats, by transecting the medial collateral ligament with (MNX) or without (SHAM) a full thickness cut through the meniscus. MNX animals were orally administered an equipotent MMP 2, 8, 9, 12, 13 inhibitor (0.25, 1 and 5 mg/kg/day) or vehicle from day 1. Chondropathy, osteophytosis, osteochondral vascularity were assessed from toluidine blue stained coronal sections of the total knee joint and weight-bearing asymmetry by incapacitance. Group differences were evaluated using 1-way analysis of variance (ANOVA) and associations as Spearman's correlation coefficients.

RESULTS

Treatment with the MMP inhibitor reduced weight-bearing asymmetry from day 14 onwards, and attenuated chondropathy (both P<0.05). Osteochondral vascularity was elevated in MNX compared with SHAM-operated animals (P<0.001) and reduced, dose-dependently, by MMP inhibitor treatment (r=-0.89, P<0.05). Reduced osteochondral vascularity and chondropathy were associated with the amelioration of weight-bearing asymmetry (both P<0.05).

CONCLUSION

Here we show that treatment with a MMP inhibitor reduces joint damage, osteochondral angiogenesis and behavioral evidence of pain. The association between osteochondral angiogenesis and pain behavior may be explained by perivascular nerve growth or stimulation of subchondral nerves following loss of osteochondral integrity. Our data suggest that targeting angiogenesis may have utility in the treatment of pain associated with structural damage in OA.

Metabolic activity of osteoarthritic knees correlates with BMI

Osteoarthritis of the knee has consistently been linked to obesity, defined as a body mass index (BMI) >30kg/m(2). It has been hypothesized that obesity may lead to osteoarthritis through increased joint pressure, accumulated microtrauma, and disruption of normal chondrocyte metabolism. These changes in chondrocyte metabolism have not been thoroughly investigated, and it is the purpose of this study to identify a relationship between BMI and altered chondrocyte metabolism in osteoarthritic tissue. Articular cartilage was harvested from the femoral condyles of patients after total knee arthroplasty, and analyzed in explant and alginate models. Glycosaminoglycan (GAG) content was measured using a dimethylmethylene blue assay and normalized to DNA content using a PicoGreen(R) assay. Studies have reported GAGs to be a reliable measurement of chondrocyte metabolism and osteoarthritis progression. Our results show a significant linear relationship of increasing BMI and increasing GAG content in both alginate and explant models (p<0.001 and p=0.001). Obese (BMI>/=30kg/m(2)) and non-obese (BMI<30kg/m(2)) comparisons also demonstrated significant differences with higher GAG/DNA content in obese individuals compared to non-obese (p=0.001 and p=0.015). The study results reveal significant relationships between GAG content and BMI in this population of osteoarthritic patients. The significant difference in GAG content between the obese and non-obese patients supports the connection between osteoarthritis and obesity previously reported. Higher patient BMI (>30kg/m(2)) may be similar to dynamic compression injuries which cause increased GAG synthesis in response to cartilage damage.

Objective assessments of medial osteoarthritic knee severity by MRI: new computer software to evaluate femoral condyle contours

An irregular contour of the medial femoral condyle (MFC) on magnetic resonance imaging (MRI) appears to indicate the severity of medial-type knee osteoarthritis (OA). The purpose of this study was to establish a system to enable objective assessments of OA knee severity using newly developed software that semi-automatically measures irregularity of the MFC. (1) We evaluated 48 patients aged 50-83 years with 55 knees of medial-type OA. The following scores were recorded: Lysholm score, visual analogue scale (VAS) and the Japanese Knee Osteoarthritis Measure (JKOM). MFC irregularity was automatically calculated by newly programmed computer software. Four parameters for condyle irregularity were calculated: (a) the average thickness of the contour (ATC), (b) the ratio of the upper surface length to the lower surface length of the contour (RUL), (c) average squared thickness of the contour (ASTC) and (d) standard deviation of the contour thickness (SDC). (2) Nine knees that underwent total knee arthroplasty were further analysed histopathologically and compared with irregularity score. Statistically, the RUL and SDC were significantly correlated with the Lysholm score, VAS and JKOM, with good reliability. Histological examinations showed that an irregular contour reflected the density of cystic lesions formed in subchondral bone. An irregularity of MFC on MRI is correlated with OA disease severity clinically and histopathologically. The new computer software is useful to objectively assess OA disease severity.

Association between radiographic features of knee osteoarthritis and pain: results from two cohort studies

OBJECTIVE

To examine the relation of radiographic features of osteoarthritis to knee pain in people with knees discordant for knee pain in two cohorts.

DESIGN

Within person, knee matched, case-control study.

SETTING AND PARTICIPANTS

Participants in the Multicenter Osteoarthritis (MOST) and Framingham Osteoarthritis studies who had knee radiographs and assessments of knee pain.

MAIN OUTCOME MEASURES

Association of each pain measure (frequency, consistency, and severity) with radiographic osteoarthritis, as assessed by Kellgren and Lawrence grade (0-4) and osteophyte and joint space narrowing grades (0-3) among matched sets of two knees within individual participants whose knees were discordant for pain status.

RESULTS

696 people from MOST and 336 people from Framingham were included. Kellgren and Lawrence grades were strongly associated with frequent knee pain-for example, for Kellgren and Lawrence grade 4 v grade 0 the odds ratio for pain was 151 (95% confidence interval 43 to 526) in MOST and 73 (16 to 331) in Framingham (both P<0.001 for trend). Similar results were also seen for the relation of Kellgren and Lawrence scores to consistency and severity of knee pain. Joint space narrowing was more strongly associated with each pain measure than were osteophytes.

CONCLUSIONS

Using a method that minimises between person confounding, this study found that radiographic osteoarthritis and individual radiographic features of osteoarthritis were strongly associated with knee pain.

Varus-valgus laxity correlates with pain in osteoarthritis of the knee

Pain during osteoarthritis (OA) of the knee does not necessarily correlate with the severity of the radiographic grade, and the mechanism of pain has not been completely clarified. The purpose of this study was to evaluate risk factors for pain in the knee OA using epidemiologic analyses. We evaluated 518 out of 4183 people over the age of 40 (156 males and 362 females) from Shinyoshitomi village, Japan. Mean ages were 63.8 years for men and 60.7 years for women. Screening included a physical examination of the knee and a standing AP roentgenogram of the bilateral knee. Radiographic OA was defined as a Kellgren-Lawrence grade 2 or higher. All data were coded and pain risk factors were evaluated using a multiple logistic regression model. Radiographic OA was observed in 18.4% of men and 26% of women. Of these subjects with OA, 10.9% of men and 32.5% of women complained of knee pain. Seven factors-age, gender, BMI, radiographic grade, varus-valgus laxity, torque of quadriceps muscles, and varus-valgus alignment-were evaluated as potential risk factors for pain. A significant increase in the odds ratio was observed with varus-valgus laxity (p=0.005; odds ratio, 3.04). Our results suggest that varus-valgus laxity is a risk factor for pain during knee OA.

The association of BMI and knee pain among persons with radiographic knee osteoarthritis: a cross-sectional study

BACKGROUND

Many people with radiographic knee osteoarthritis (RKOA) do not present with pain. It is suspected that such persons tend toward lower body mass index (BMI). The purpose of the study was to explore the relationship between BMI and knee pain among persons with RKOA.

METHODS

Subjects in the Clearwater Osteoarthritis Study with RKOA (N = 576) were classified as reporting knee pain (Pain) or no knee pain (No Pain). WHO-classified BMI categories were compared by pain status. Odds ratios were calculated for the four elevated BMI groups, with the normal BMI group as the reference group. Elevated BMI was the risk factor, and knee pain status was the outcome factor.

RESULTS

Pain subjects presented with a higher mean BMI (30.4 kg/m2) compared with No Pain subjects (27.5 kg/m2) (p < 0.0001). Unadjusted and adjusted odds ratios demonstrated a positive association between BMI group and pain for each successive elevated BMI category. Adjusted odds ratios ranged from 1.6 for the Pre-obese group (p < 0.05) to 7.5 for the Obese III group (p < 0.0001).

CONCLUSION

Among subjects with RKOA, those presenting with an elevated BMI had a greater likelihood of knee pain compared to subjects with a normal BMI, and this chance rose with each successive elevated BMI category. As BMI is a modifiable risk factor, longitudinal research is needed to confirm these findings and elucidate the mechanisms underlying this relationship.

Unravelling the relationship between age, nociception and joint destruction in naturally occurring osteoarthritis of Dunkin Hartley guinea pigs

Osteoarthritis (OA) is a debilitating and painful disease, the incidence of which increases with advancing age. One of the confounding aspects of OA is that there is a disconnect between the severity of joint degeneration and the intensity of pain reported. This study examined the relationship between age, joint nociception, and joint pathology in an animal model of naturally occurring OA. Dunkin Hartley guinea pigs were grouped according to age: young (2-5 months) and senescent (17-37 months). Joint nociception was objectively measured in these animals by recording electrophysiologically from knee joint primary afferents in response to non-noxious and noxious movements of the knee. Joint pathology in the same knees was then determined by histomorphology and micro-computerized tomography (micro-CT). A principal components analysis was carried out on the data to determine if any correlation exists between each of the measured variables. In aged guinea pigs, 33% of joint mechanosensory nerves were spontaneously active, whereas young animals showed no such neural activity at rest. The frequency of afferent firing evoked by noxious movements was greater in old guinea pigs. Micro-CT and histopathological determination of OA positively correlated with age; however, there was no significant correlation between the severity of joint degeneration and nociception. In the Dunkin Hartley model of inveterate OA, the level of joint pathology correlates well with increasing age. This study also provides the first objective evidence that there is no correlation between joint nociception and articular damage, thereby corroborating the clinical observation that pain is a poor predictor of OA severity.

Lifetime risk of symptomatic knee osteoarthritis

OBJECTIVE

To estimate the lifetime risk of symptomatic knee osteoarthritis (OA), overall and stratified by sex, race, education, history of knee injury, and body mass index (BMI).

METHODS

The lifetime risk of symptomatic OA in at least 1 knee was estimated from logistic regression models with generalized estimating equations among 3,068 participants of the Johnston County Osteoarthritis Project, a longitudinal study of black and white women and men age >or=45 years living in rural North Carolina. Radiographic, sociodemographic, and symptomatic knee data measured at baseline (1990-1997) and first followup (1999-2003) were analyzed.

RESULTS

The lifetime risk of symptomatic knee OA was 44.7% (95% confidence interval [95% CI] 40.0-49.3%). Cohort members with history of a knee injury had a lifetime risk of 56.8% (95% CI 48.4-65.2%). Lifetime risk rose with increasing BMI, with a risk of 2 in 3 among those who were obese.

CONCLUSION

Nearly half of the adults in Johnston County will develop symptomatic knee OA by age 85 years, with lifetime risk highest among obese persons. These current high risks in Johnston County may suggest similar risks in the general US population, especially given the increase in 2 major risk factors for knee OA, aging, and obesity. This underscores the immediate need for greater use of clinical and public health interventions, especially those that address weight loss and self-management, to reduce the impact of having knee OA.

Screening for hip and knee osteoarthritis in the general population: predictive value of a questionnaire and prevalence estimates

OBJECTIVE

To study the feasibility and validity of a two-step telephone screening procedure for symptomatic knee and hip osteoarthritis (OA) in the general population.

METHOD

The screening questionnaire was based on signs and symptoms, previous diagnosis of OA and validated OA criteria. A random sample of telephone numbers was obtained and, at each number, one person aged 40-75 years was included. A physical examination and knee or hip radiographs were offered when the screen was positive. A sample of subjects with negative screens was also examined. The diagnosis of hip/knee OA was based on the American College of Rheumatology criteria for signs and symptoms and Kellgren-Lawrence radiographic stage 2 or greater. Prevalence rates were estimated with correction for the performance of the screening procedure.

RESULTS

Of 1380 subjects, 479 had positive screens, among whom 109 were evaluated; symptomatic radiographic OA was found in 50 subjects, at the knee (n = 35) or hip (n = 20). Corrected prevalence estimates of symptomatic OA were 7.6% (6.4%-8.8%) for the knee and 5% (3.9%-6.1%) for the hip. The screening procedure had 87% (95% CI 79% to 95%) sensitivity and 92% (95% CI 91% to 93%) specificity for detecting knee OA and respectively 93% (95% CI 86% to 100%) and 93% (95% CI 92% to 94%) for hip OA.

CONCLUSION

This study establishes the feasibility of telephone screening for symptomatic knee/hip OA, which could be used for a nationwide prevalence study. Pain and previous OA diagnosis were the best items for detecting symptomatic OA.

Evaluations of radiographic joint space--do they adequately predict cartilage conditions in the patellofemoral joint of the patients undergoing total knee arthroplasty for advanced knee osteoarthritis?

OBJECTIVE

To determine whether assessments of patellofemoral (PF) joint space reliably predict the cartilage conditions in the PF joint of the patients undergoing total knee arthroplasty (TKA) for advanced knee osteoarthritis.

METHODS

Radiographic joint spaces and gross cartilage conditions in the PF joint were assessed in 151 osteoarthritic knees undergoing TKA. Minimum joint space widths (MJSWs) in the medial and lateral compartments of the PF joint were measured separately on Merchant radiographs. Degrees of joint space were graded as normal, narrowed and obliterated, and expected locations of significant cartilage lesions were classified as medial, lateral, and global. Cartilage lesions were grossly assessed in terms of their severity (depth and size) and location. Cross-table analyses and kappa statistics were used to determine the level of agreements between radiographic and gross assessments and the diagnostic accuracies of the radiographic assessments.

RESULTS

The agreements between the radiographic assessments and the gross assessments on the lesion severities and locations were only fair [kappa coefficient (k)=0.288 and 0.211, respectively]. The cross-table analyses demonstrated that 45 (47.4%) of 95 knees with a normal radiographic joint space had moderate or severe cartilage degeneration of the PF joint identified with gross assessments. In the radiographic assessments, the lateral compartment of the PF joint was the most frequent location of joint space narrowing (71.4%) whereas in the gross assessments, the medial compartment of the PF joint was the most frequent location of significant cartilage lesion (48.1%). Diagnostic accuracies on the lesion severities and locations were generally poor.

CONCLUSION

This study demonstrates that prediction of the cartilage conditions of the PF joint by the radiographic joint space can be inaccurate.

The discordance between clinical and radiographic knee osteoarthritis: a systematic search and summary of the literature

Background

Studies have suggested that the symptoms of knee osteoarthritis (OA) are rather weakly associated with radiographic findings and vice versa. Our objectives were to identify estimates of the prevalence of radiographic knee OA in adults with knee pain and of knee pain in adults with radiographic knee OA, and determine if the definitions of x ray osteoarthritis and symptoms, and variation in demographic factors influence these estimates.

Methods

A systematic literature search identifying population studies which combined x rays, diagnosis, clinical signs and symptoms in knee OA. Estimates of the prevalence of radiographic OA in people with knee pain were determined and vice versa. In addition the effects of influencing factors were scrutinised.

Results

The proportion of those with knee pain found to have radiographic osteoarthritis ranged from 15–76%, and in those with radiographic knee OA the proportion with pain ranged from 15% – 81%. Considerable variation occurred with x ray view, pain definition, OA grading and demographic factors

Conclusion

Knee pain is an imprecise marker of radiographic knee osteoarthritis but this depends on the extent of radiographic views used. Radiographic knee osteoarthritis is likewise an imprecise guide to the likelihood that knee pain or disability will be present. Both associations are affected by the definition of pain used and the nature of the study group. The results of knee x rays should not be used in isolation when assessing individual patients with knee pain.

Comparative evaluation of three semi-quantitative radiographic grading techniques for knee osteoarthritis in terms of validity and reproducibility in 1759 X-rays: report of the OARSI-OMERACT task force

OBJECTIVE

The objective of this work was to compare the measurement properties of three categorical X-ray scoring methods of knee osteoarthritis (OA), both on semiflexed and extended views.

METHODS

In data obtained from trials and cohorts, X-rays were graded using Kellgren and Lawrence (KL), the OA Research Society International (OARSI) joint space narrowing score, and measurement of joint space width (JSW). JSW was analyzed as a categorical variable. Construct validity was assessed through logistic regression between X-ray stages and Western Ontario and McMaster Universities OA Index. Inter-observer reliability was assessed in 50 subjects for extended views by weighted kappa. Intra-observer reliability and sensitivity to change were assessed separately for extended and semiflexed views in 50 patients who had both views performed, over a 30-month interval, by weighted kappa and standardized response mean (SRM).

RESULTS

Extended views were available from three trials and two cohorts (1759 X-rays), including one trial in which both extended and semiflexed views (antero-posterior) were obtained. Correlation with clinical parameters was low for the three scoring methods, except for the single community-based cohort. Inter-rater reliability was higher for categorical JSW in extended views (kappa, 0.86 vs 0.56 and 0.48 for KL and OARSI, respectively). Intra-rater reliability was higher for categorical JSW, both in extended views (0.83 vs 0.61 and 0.71) and in semiflexed views (0.89 vs 0.50 and 0.67). Sensitivity to change was also higher for categorical JSW, particularly in semiflexed views (SRM, 0.49 vs 0.22 and 0.34).

CONCLUSION

These results indicate categorical JSW, in particular on semiflexed views, may be the preferred method to evaluate structural severity in knee OA clinical trials.

Clinical value of (99m)Tc-methylene diphosphonate (MDP) bone single photon emission computed tomography (SPECT) in patients with knee osteoarthritis

OBJECTIVE

To evaluate that single photon emission computed tomography (SPECT) could reflect the clinical severity of knee osteoarthritis (OA) and to determine the clinical usefulness of SPECT as a sensitive imaging method detecting early OA.

METHODS

Sixty knees of thirty OA patients were examined with (99m)Tc-methylene diphosphonate (MDP) bone SPECT, the intensity of uptake was graded and the sites of uptake were localized. One hundred millimeter visual analog scale (VAS), Western Ontario McMaster Universities (WOMAC) Osteoarthritis Index scores and physical examination were assessed. Simple radiograph and musculoskeletal ultrasonography (US) were performed, and Kellgren-Lawrence (K-L) grades were determined. The relationships between clinical findings, simple radiographic findings, US findings and the intensity of uptake in SPECT were analyzed.

RESULTS

There were increased uptakes in 91.7% of the knees, and patella and medial tibial condyle were the most common sites of the uptakes. Symptomatic knees had significantly higher intensity of uptake than asymptomatic knees. Uptake intensity of medial compartment in SPECT well correlated with clinical findings, such as VAS, WOMAC scores, and physical examination, as well as US findings. Even in the symptomatic knees without abnormal radiographic findings, the increased uptake was observed in SPECT.

CONCLUSION

In patients with knee OA, SPECT findings are well correlated with clinical findings, such as pain scores and physical examinations, and SPECT appears to be a sensitive tool for early detection of knee OA. SPECT information could be useful for determining clinical severity of knee OA and for diagnosing early OA more effectively.

Knee Images Digital Analysis (KIDA): a novel method to quantify individual radiographic features of knee osteoarthritis in detail

OBJECTIVE

Radiography is still the golden standard for imaging features of osteoarthritis (OA), such as joint space narrowing, subchondral sclerosis, and osteophyte formation. Objective assessment, however, remains difficult. The goal of the present study was to evaluate a novel digital method to analyse standard knee radiographs.

METHODS

Standardized radiographs of 20 healthy and 55 OA knees were taken in general practise according to the semi-flexed method by Buckland-Wright. Joint Space Width (JSW), osteophyte area, subchondral bone density, joint angle, and tibial eminence height were measured as continuous variables using newly developed Knee Images Digital Analysis (KIDA) software on a standard PC. Two observers evaluated the radiographs twice, each on two different occasions. The observers were blinded to the source of the radiographs and to their previous measurements. Statistical analysis to compare measurements within and between observers was performed according to Bland and Altman. Correlations between KIDA data and Kellgren & Lawrence (K&L) grade were calculated and data of healthy knees were compared to those of OA knees.

RESULTS

Intra- and inter-observer variations for measurement of JSW, subchondral bone density, osteophytes, tibial eminence, and joint angle were small. Significant correlations were found between KIDA parameters and K&L grade. Furthermore, significant differences were found between healthy and OA knees.

CONCLUSION

In addition to JSW measurement, objective evaluation of osteophyte formation and subchondral bone density is possible on standard radiographs. The measured differences between OA and healthy individuals suggest that KIDA allows detection of changes in time, although sensitivity to change has to be demonstrated in long-term follow-up studies.

The use of hamstrings in anterior cruciate ligament reconstruction in patients over 40 years

INTRODUCTION

Anterior cruciate ligament reconstruction is an increasingly established method even in patients over 40 years old. Recent studies with regard to this procedure used BTB transplants. We did a retrospective follow-up examination on over-40-year-old patients with anterior cruciate ligament reconstruction using hamstring transplants and compared them to a younger control group. Our hypothesis is that functional outcome after ACL-reconstruction is comparable in patients under and over 40 years of age.

MATERIALS AND METHODS

Retrospective follow-up examinations in 28 patients, 11 women and 17 men. The average age at the time of operation was 43.5 years (range 40-61). The average follow-up period was 30.4 months. Half of the patients had a femoral fixation in TransFix technique (Arthrex, Naples, USA), while the other 14 patients had a femoral bioscrew fixation (Arthrex, Naples, USA). Objectivity was ensured by measurements of anterior tibial translation with the rolimeter (Aircast). The functional outcome was determined by clinical scores (Tegner activity scale, Lysholm knee score, OAK score and IKDC score). The degree of arthrosis was defined on the basis of tunnelview radiographs and compared to the non-operated site. Functional results and degree of laxity was compared to a sex matched control group (mean age 28.0).

RESULTS

The median values for the Lysholm knee score were 91.5 points (range 69-100), for the OAK score 93.5 points (range 67-100) and for the IKDC score 83.35 points (range 62.1-100). For the Tegner activity scale values of 4.5 points (range 3-8) were obtained. In the IKDC knee examination form we found normal and nearly normal values in 86% and in the OAK examination score good and very good results in 82%. Ninety-three percent had an AP side-to-side difference of <5 mm in the operated knee. Subjectively, 75% reported that they had no feeling of instability, even when practising sport. No significant correlation between functional outcome and patients' age was present. Furthermore there were no significant differences between the investigated and the younger control group. The most advanced signs of arthrosis were found in the medial compartment of the operated side (degree A: 36%; degree B: 46%; degree C: 14%; degree D: 4%).

CONCLUSION

The predominantly good results and a high level of patient satisfaction show that anterior cruciate ligament reconstruction is justified even in over-40-year-old patients with persistend subjective symptomatic anterior knee instability. The indication for reconstruction should be based on individual factors such as level of activity or subjective feeling of instability rather than on a dogmatic age limit. Advanced arthrotic changes compared to the healthy side, might be due to a too long period of preoperative decision making.

Association between radiological findings and symptoms at the patellofemoral joint in advanced knee osteoarthritis

We investigated the association between the radiological findings and the symptoms arising from the patellofemoral joint in advanced osteoarthritis (OA) of the knee. Four radiological features, joint space narrowing, osteophyte formation, translation of the patella and focal attrition were assessed in 151 consecutive osteoarthritic knees in 107 patients undergoing total knee replacement. The symptoms which were assessed included anterior knee pain which was scored, the ability to rise from a chair and climb stairs, and quadriceps weakness.

Among the radiological features, only patellar translation and obliteration of the joint space had a statistically significant association with anterior knee pain (odds ratio (OR) 4.85; 95% confidence interval (CI) 1.83 to 12.88 and OR 11.23; 95% CI 2.44 to 51.62) respectively. Patellar translation had a statistically significant association with difficulty in rising from a chair (OR 9.06; 95% CI 1.75 to 45.11). Other radiological features, including osteophytes, joint space narrowing, and focal attrition had no significant association.

Our study indicates that the radiological findings of patellar translation and significant loss of cartilage are predictive of patellofemoral symptoms and functional limitation in advanced OA of the knee.

A cross sectional study of requests for knee radiographs from primary care

BACKGROUND

Knee pain is the commonest pain complaint amongst older adults in general practice. General Practitioners (GPs) may use x rays when managing knee pain, but little information exists regarding this process. Our objectives, therefore, were to describe the information GPs provide when ordering knee radiographs in older people, to assess the association between a clinical diagnosis of osteoarthritis (OA) and the presence of radiographic knee OA, and to investigate the clinical content of the corresponding radiologists' report.

METHODS

A cross sectional study of GP requests for knee radiographs and their matched radiologists' reports from a local radiology department. Cases, aged over 40, were identified during an 11-week period. The clinical content of the GPs' requests and radiologists' reports was analysed. Associations of radiologists' reporting of i) osteoarthritis, ii) degenerative disease and iii) individual radiographic features of OA, with patient characteristics and clinical details on the GPs' requests, were assessed.

RESULTS

The study identified 136 cases with x ray requests from 79 GPs and 11 reporting radiologists. OA was identified clinically in 19 (14%) of the requests, and queried in another 31 (23%). The main clinical descriptor was pain in 119 cases (88%). Radiologists' reported OA in 22% of cases, and the features of OA were mentioned in 63%. Variation in reporting existed between radiologists. The commonest description was joint space narrowing in 52 reports (38%). There was an apparent although non significant increase in the reporting of knee OA when the GP had diagnosed or queried it (OR 1.95; 95% CI 0.76, 5.00).

CONCLUSION

The features of radiographic OA are commonly reported in those patients over 40 whom GPs send for x ray. If OA is clinically suspected, radiologists appear to be more likely to report its presence. Further research into alternative models of referral and reporting might identify a more appropriate imaging policy in knee disorders for primary care.

Irregularity of medial femoral condyle on MR imaging serves as a possible indicator of objective severity of medial-type osteoarthritic knee-a pilot study

Irregularly described contour of the femur and the tibia on magnetic resonance (MR) imaging is commonly seen in osteoarthritic (OA) knees. The aim of this study is to examine the relationship between irregularity of contour of medial femoral condyle (tentatively named I-index) and severity of OA. Twenty-six medial-type OA knees with a mean age of 63.8 were studied. All patients had undergone MR imaging to measure the I-index using image analysis software, and its relationship to Lysholm score was examined. The I-index negatively correlated with Lysholm score (r = -0.55, p < 0.01). The I-index for each Kellgren and Lawrence grade was significantly different. We have concluded that the I-index is a potent indicator to objectively describe the severity of OA especially for the advanced stage OA.

The influence of gait pattern on signs of knee osteoarthritis in older adults over a 5-11 year follow-up period: a case study analysis

There is evidence that joint load is a factor in the development of osteoarthritis (OA) and, while altered gait profiles have been linked with OA, it is unknown if abnormal gait is a cause or effect of the disease. While the knee's adduction moment has been implicated in the development and progression of knee OA, it is also known that shearing forces are detrimental to the health of cartilage. The purpose of this pilot study was to examine the adduction moment and gait shear forces to determine if they may lead to signs of knee OA in older adults as they age. Knee gait kinetics, standardized radiographs and a questionnaire were collected on 28 older adults (M:13) during an initial visit, and 5 to 11 years later. Radiographic score increased (knees became more osteoarthritic in 15 of 28 subjects) over time. However, gait time-distance measures remained constant in disease free participants. Two returning participants developed symptoms and radiographic evidence of knee OA. The subject with the largest adduction moment developed signs of medial OA while the subject with the smallest adduction moment developed signs of lateral OA. In addition, there was a strong correlation between the magnitudes of the adduction moment and lateral-medial shear force that needs to be investigated further. Results suggest that gait can remain stable over time in older adults. Also, the medial and lateral OA case study findings suggest that the extreme gait profiles seen in these two participants may be important in explaining cartilage breakdown and the development of OA. This longitudinal study would suggest that perhaps it is the abnormal gait pattern that leads to the development of OA, although a much larger study would be needed to confirm this finding.

Symptoms and radiographic osteoarthritis: not as discordant as they are made out to be?

OBJECTIVES

Joint pain and radiographic osteoarthritis are often discordant.

AIM

To investigate this issue more closely by studying the detailed nature of pain and disability, and how this relates to radiographic osteoarthritis.

METHODS

Population-based study of 819 adults aged >or=50 years with knee pain. The severity of knee pain, stiffness and disability was measured using a validated scale (the Western Ontario and McMaster Universities (WOMAC) Score) and pain persistence was recorded. Global severity was measured by the graded chronic pain scale. Three radiographic views of the knees were obtained-weight-bearing posteroanterior metatarsophalangeal, supine skyline and supine lateral.

RESULTS

745 participants with knee pain in the past 6 months were eligible (mean age 65 years, 338 men). Radiographic osteoarthritis was more common in those with a longer history and more persistent symptoms. A strong trend was found of radiographic osteoarthritis being more strongly associated with higher WOMAC scores for pain severity, stiffness and disability (adjusted odds ratio (95% confidence interval (CI)) for highest v lowest WOMAC category: 3.7 (2.0 to 6.7), 3.0 (2.0 to 4.6) and 2.8 (1.6 to 5.0), respectively). Those individual WOMAC items for pain and disability pertaining to weight-bearing mobility were the most strongly associated with radiographic osteoarthritis. Combining pain persistence and global severity, persistent severe pain was associated with a significant increase in the occurrence of radiographic osteoarthritis (2.6 (95% CI 1.5 to 4.7)).

CONCLUSIONS

A consistent association was found between severity of pain, stiffness and physical function and the presence of radiographic osteoarthritis. This study highlights the potential contribution of underlying joint disease to the degree of pain and disability.

Correlates of knee pain in older adults: Tasmanian Older Adult Cohort Study

OBJECTIVE

To describe the association between chondral defects, bone marrow lesions, knee and hip radiographic osteoarthritis (OA), and knee pain.

METHODS

Knee pain was assessed by the Western Ontario and McMaster Universities Osteoarthritis Index. T1- and T2-weighted fat saturation magnetic resonance imaging was performed on the right knee to assess chondral defects and subchondral bone marrow lesions. Radiography was performed on the right knee and hip and scored for radiographic OA. Body mass index (BMI) and knee extension strength were measured.

RESULTS

A total of 500 randomly selected men and women participated. The prevalence of knee pain was 48%. In multivariable analysis, prevalent knee pain was significantly associated with medial tibial chondral defects (odds ratio [OR] 2.32, 95% confidence interval [95% CI] 1.02-5.28 for grade 3 versus grade 2 or less; OR 4.93, 95% CI 1.07-22.7 for grade 4 versus grade 2 or less), bone marrow lesions (OR 1.44, 95% CI 1.04-2.00 per compartment), and hip joint space narrowing (OR 1.36, 95% CI 1.07-1.73 per unit), as well as greater BMI and lower knee extension strength. It was not significantly associated with radiographic knee OA. These variables were also associated with more severe knee pain. In addition, there was a dose response association between knee pain and number of sites having grade 3 or 4 chondral defects (OR 1.39, 95% CI 1.12-1.73 per site), with all subjects having knee pain if all compartments of the knee had these defects.

CONCLUSION

Knee pain in older adults is independently associated with both full and non-full-thickness medial tibial chondral defects, bone marrow lesions, greater BMI, and lower knee extension strength, but is not associated with radiographic knee OA. The association between radiographic hip OA and knee pain indicates that referred pain from the hip needs to be considered in unexplained knee pain.

Clinical and ultrasonographic findings related to knee pain in osteoarthritis

OBJECTIVES

To determine clinical and sonographic factors associated with painful episodes in patients with knee osteoarthritis (OA).

METHODS

In this cross-sectional controlled study, patients with primary knee OA (ACR criteria) were prospectively placed into two groups. Group A: 81 patients with knee pain during physical activity >or=30 mm in visual analogue scale (VAS) for pain for at least 48 h prior to inclusion; Group B: 20 patients without knee pain from at least 1 month prior to inclusion. Clinical parameters, knee radiographic and ultrasonographic findings were collected. The sonographic study assessed joint effusion in the suprapatellar pouch, infrapatellar superficial and deep bursitis, meniscal lesions, anserine tendinobursitis, and Baker's cyst.

RESULTS

Group A patients tended to be older and heavier women than group B (P<0.05). The most frequent radiographic stage was III (57%) in group A, and I (35%) and II (35%) in group B, showing differences in the distribution of each radiographic stage (P<0.005). The most frequent ultrasonographic finding in group A was suprapatellar effusion (79%), and in group B it was meniscal lesions (40%). Ultrasonographic findings showed in group A a significant increase of suprapatellar effusion (P<0.001) and a tendency towards an increase of Baker's cyst (P=0.06). Suprapatellar effusion, Baker's cyst, and body mass index (BMI) were the factors associated with the appearance of pain after the logistic regression analysis.

CONCLUSIONS

Suprapatellar effusion, Baker's cyst, and higher BMI are more frequent and seem to be risk factors of painful flare in OA of the knee.

Associations between pain, function, and radiographic features in osteoarthritis of the knee

OBJECTIVE

To assess the associations between pain, loss of function, and radiographic changes in knee osteoarthritis (OA), taking into account both the patellofemoral and tibiofemoral compartments.

METHODS

Both knees of 167 community-based patients with OA in at least 1 of their knees were assessed. Pain was measured by visual analog scale, and function was assessed using the Western Ontario and McMaster Universities Osteoarthritis Index. Anteroposterior standing radiographs with the knee in extension and lateral 30 degrees flexion were obtained and assessed for the Kellgren/Lawrence score and for individual features (osteophytes, joint space narrowing, and subchondral bone sclerosis) in each compartment.

RESULTS

Knees with structural changes in both compartments were more likely to be painful and to be associated with loss of function than were knees in which only 1 compartment was affected. The individual feature most strongly associated with pain was subchondral bone sclerosis.

CONCLUSION

Studies exploring the associations between structural and symptomatic knee OA need to include an assessment of the patellofemoral compartment, and individual radiographic features rather than a global severity score should be considered in these studies.

Personal meanings in the construction of need for total knee replacement surgery

This study explores patients' personal meanings of knee osteoarthritis (OA) and total knee replacement (TKR). Personal meanings are important because decisions regarding the need for TKR do not seem to be explained by symptoms alone. A total of 18 semi-structured interviews were conducted with a purposive sample of respondents who were listed for TKR at one UK specialist orthopaedic hospital, and who had lower than average disease burden according to standard quantitative criteria. Data were analysed using interpretive phenomenological analysis. Several themes related to need for TKR emerged: adoption of the medical model, a person's social network, pain, functional loss, feelings of vulnerability, dependency, low mood and fatigue, ideas related to disease progression and expectations of TKR. Results suggest that the decision to undergo TKR is not related to symptoms alone, but to personal meanings. Some of these personal meanings may not be useful in accurately assessing the need for TKR, and may result in mis-targeting of treatment. It is important for health professionals to explore and tackle personal meanings when considering treatment. In particular, it may be important to consider gender differences that may influence when men and women are listed for TKR. For example: women may be less likely to discuss treatment options with their doctor; they may be more likely to have heard negative examples of TKR from friends or family; they may be more likely to discuss pain and mobility issues than activities requiring higher function; and they may be more likely to discuss the effect on their mood and the emotional impact of OA.

The effect of patient characteristics on variability in pain and function over two years in early knee osteoarthritis

Background

Large variations in pain and function are seen over time in subjects at risk for and with radiographic knee osteoarthritis (OA). We hypothesized that this variation may be related not only to knee OA but also to patient characteristics. The objective of this study was to investigate the influence of age, gender, and body mass index (BMI) on clinically relevant change in pain and function over two years in subjects at high risk for or with knee OA.

Methods

We assessed 143 individuals (16% women, mean age 50 years [range 27–83]) twice; 14 and 16 years after isolated meniscectomy. Subjects completed one disease-specific questionnaire, the Knee injury and Osteoarthritis Outcome Score (KOOS) and one generic measure, the SF-36. Individuals with a BMI between 25 and 29.9 were considered overweight, while individuals with a BMI of 30 or more were considered obese.

Results

Subjects aged 46–56 (the middle tertile) were more likely to change (≥10 points on a 0–100 scale) in the KOOS subscale Activities of Daily Living (ADL) than younger subjects (odds ratio [OR] 4.5, 95% confidence interval [95% CI] 1.5–13.0). Essentially the same result was obtained after adjusting for baseline values. Overweight or obesity was a risk factor for clinically relevant change for knee pain (OR 2.4, 95% CI 1.0 – 5.8, OR 4.0, 95% CI 1.2 – 13.6) and obesity for change in ADL (OR 4.3, 95% CI 1.2 – 15.4). The results did not remain significant when adjusted for the respective baseline value. Being symptomatic was strongly associated with increased variation in pain and function while presence or absence of radiographic changes did not influence change over two years in this cohort.

Conclusion

In a population highly enriched in early-stage and established knee OA, symptomatic, middle-aged, and overweight or obese subjects were more likely to vary in their knee function and pain over two years. The natural course of knee pain and function may be associated with subject characteristics such as age and BMI.

The prevalence of knee pain and symptomatic knee osteoarthritis among veteran traumatic amputees and nonamputees

OBJECTIVE

To determine whether amputees have an increased risk of knee pain or symptomatic osteoarthritis (OA) compared with nonamputees.

DESIGN

Retrospective cohort study.

SETTING

Veterans Administration Patient Treatment and Outpatient Care files.

PARTICIPANTS

All male unilateral (transtibial or transfemoral) traumatic amputee patients and a random sample of male nonamputees. Patients were excluded if they were younger than 40 years, had sustained a significant injury to their knee(s), or had a rheumatic disease.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The prevalence of knee pain and symptomatic knee OA.

RESULTS

The age and average weight-adjusted prevalence ratio of knee pain among transtibial amputees, compared with nonamputees, was 1.3 (95% confidence interval [CI], 0.7-2.1) for the knee of the intact limb and 0.2 (95% CI, .05-0.7) for the knee of the amputated limb. The standardized prevalence ratio of knee pain in the intact limb and symptomatic OA among transfemoral amputees, compared with nonamputees, was 3.3 (95% CI, 1.5-6.3) and 1.3 (95% CI, 0.2-4.8), respectively.

CONCLUSIONS

Stresses on the contralateral knee of amputees may contribute to secondary disability. Possible explanations include gait abnormalities, increased physiologic loads on the knee of the intact limb, and the hopping and stumbling behavior common in many younger amputees.

Association between radiographic joint space narrowing, function, pain and muscle power in severe osteoarthritis of the knee

OBJECTIVE

To examine the association between radiographic classification of severe knee osteoarthritis and measurements of function, pain and power.

DESIGN

Cross-sectional study.

SETTING

Specialist orthopaedic hospital.

SUBJECTS

One hundred and twenty-three patients on the waiting list for elective knee arthroplasty.

OUTCOME MEASURES

Weight-bearing antero-posterior radiographs scored for severity of osteoarthritis using the Kellgren and Lawrence scale. Function measured using the function subscale of the WOMAC (Western Ontario and McMaster Universities) index, timed tests of walking speed and sit-to-stand. Pain measured using the pain subscale of the WOMAC index and a visual analogue scale. Extensor strength of the lower limb measured with the leg extensor power rig.

RESULTS

Within any radiographic grade there was considerable variation in function: WOMAC function for patients with grade 2 mean 64 (47-86), grade 3 mean 47 (12-89) grade 4 mean 45 (2-92). There was poor correlation between radiographic score function, pain or muscle power, with no statistically significant associations. A wide range of scores was also seen within patients with the same radiographic grade.

CONCLUSIONS

Radiographic score was not found to be closely associated with function. Amongst patients with the same radiographic score there was considerable variation in function, pain and power.

High prevalence of knee osteoarthritis, pain, and functional limitations in female soccer players twelve years after anterior cruciate ligament injury

OBJECTIVE

To determine the prevalence of radiographic knee osteoarthritis (OA) as well as knee-related symptoms and functional limitations in female soccer players 12 years after an anterior cruciate ligament (ACL) injury.

METHODS

Female soccer players who sustained an ACL injury 12 years earlier were examined with standardized weight-bearing knee radiography and 2 self-administered patient questionnaires, the Knee Injury and Osteoarthritis Outcome Score questionnaire and the Short Form 36-item health survey. Joint space narrowing and osteophytes were graded according to the radiographic atlas of the Osteoarthritis Research Society International. The cutoff value to define radiographic knee OA approximated a Kellgren/Lawrence grade of 2.

RESULTS

Of the available cohort of 103 female soccer players, 84 (82%) answered the questionnaires and 67 (65%) consented to undergo knee radiography. The mean age at assessment was 31 years (range 26-40 years) and mean body mass index was 23 kg/m2 (range 18-40 kg/m2). Fifty-five women (82%) had radiographic changes in their index knee, and 34 (51%) fulfilled the criterion for radiographic knee OA. Of the subjects answering the questionnaires, 63 (75%) reported having symptoms affecting their knee-related quality of life, and 28 (42%) were considered to have symptomatic radiographic knee OA. Slightly more than 60% of the players had undergone reconstructive surgery of the ACL. Using multivariate analyses, surgical reconstruction was found to have no significant influence on knee symptoms.

CONCLUSION

A very high prevalence of radiographic knee OA, pain, and functional limitations was observed in young women who sustained an ACL tear during soccer play 12 years earlier. These findings constitute a strong rationale to direct increased efforts toward prevention and better treatment of knee injury.

Similar group mean scores, but large individual variations, in patient-relevant outcomes over 2 years in meniscectomized subjects with and without radiographic knee osteoarthritis

BACKGROUND

Epidemiological studies have, so far, identified factors associated with increased risk for incident or progressive OA, such as age, sex, heredity, obesity, and joint injury. There is, however, a paucity of long-term data that provide information on the nature of disease progression on either group or individual levels. Such information is needed for identification of study cohorts and planning of clinical trials. The aim of the study was, thus, to assess the variation in pain and function on group and individual level over 2 years in previously meniscectomized individuals with and without radiographic knee osteoarthritis (OA).

METHODS

143 individuals (16% women, mean age at first assessment 50 years [range 27-83]) were assessed twice; approximately 14 and 16 years after isolated meniscectomy, with a median interval of 2.3 years (range 2.3-3.0). Radiographic OA (as assessed at the time of second evaluation) was present in the operated knee in 40%, and an additional 19% had a single osteophyte grade 1 in one or both of the tibiofemoral compartments. Subjects completed the self-administered and disease-specific Knee injury and Osteoarthritis Outcome Score (KOOS).

RESULTS

There were no significant changes in the group mean KOOS subscale scores over the 2-year period. However, a great variability over time was seen within individual subjects. Out of 143 subjects, 16% improved and 12% deteriorated in the subscale Pain, and 13% improved and 14% deteriorated in the subscale ADL > or = 10 points (the suggested threshold for minimal perceptible clinical change). Similar results were seen for remaining subscales.

CONCLUSION

Group mean scores for this study cohort enriched in incipient and early-stage knee OA were similar over 2 years, but pain, function and quality of life changed considerably in individuals. These results may be valid also for other at risk groups with knee OA, and motivate further careful examination of the natural history of OA, as well as properties of the OA outcome instruments used. Longitudinal outcome data in OA studies need to be analyzed both on an individual and a group level.

Risk factors for symptomatic knee osteoarthritis fifteen to twenty-two years after meniscectomy

OBJECTIVE

To evaluate the influence of age, sex, body mass index (BMI), extent of meniscal resection, cartilage status, and knee load on the development of radiographically evident osteoarthritis (OA) of the knee and knee symptoms after meniscal resection.

METHODS

We evaluated 317 patients with no cruciate ligament injury (mean +/- SD age 54 +/- 11 years) who had undergone meniscal resection 15-22 years earlier (followup rate 70%), with radiographic and clinical examination. The Knee injury and Osteoarthritis Outcome Score was used to quantify knee-related symptoms. Sixty-eight unoperated subjects identified from national population records were included as a reference group.

RESULTS

Symptomatic radiographic OA (corresponding to Kellgren/Lawrence grade > or =2) was present in 83 of 305 operated knees (27%) and 7 of 68 control knees (10%) (relative risk 2.6, 95% confidence interval [95% CI] 1.3-6.1). Patients who had undergone total meniscectomy and subjects with obesity (BMI > or =30) had a greater likelihood of tibiofemoral radiographic OA than those who had undergone partial meniscal resection and those with a BMI <25, respectively. Furthermore, degenerative meniscal tear, intraoperative cartilage changes, and lateral meniscectomy were associated with radiographic OA more frequently than were longitudinal tear, absence of cartilage changes, and medial meniscectomy, respectively. Symptomatic tibiofemoral or patellofemoral radiographic OA was associated with obesity, female sex, and degenerative meniscal tear.

CONCLUSION

Contributing risk factors for OA development after meniscal resection are similar to risk factors for common knee OA. Systemic factors and local biomechanical factors interact. Obesity, female sex, and preexisting early-stage OA are features associated with poor self-reported and radiographic outcome. Partial meniscal resection is associated with less radiographic OA over time than is total meniscectomy.

Aging or osteoarthritis: which is the problem?

OA is not an inevitable consequence of aging, but aging-related changes in the musculoskeletal system increase the risk of developing OA if other risk factors are also present. The joint is a functioning biomechanical unit of the neuromuscular system. Factors that contribute to the development of joint pain and loss of joint function include those associated with aging, those associated with underuse or misuse of the musculoskeletal system, and those associated directly with the development of OA. Complex interactions exist among many of these factors such as strength, balance, and proprioception, which are affected by aging, underuse, and OA. Many older adults who have joint pain and loss of function do not exhibit structural changes of OA that can be detected by standard radiography. When structural damage is present, its contribution to pain and disability is not always clear. In the absence of pharmacologic agents that can prevent the progression of structural damage in OA, management of older adults who have joint pain and loss of function should focus on improving neuromuscular function and preventing further declines.

Radiographic assessment of osteoarthritis: analysis of disease progression

Osteoarthritis (OA) is one of the most prevalent and disabling chronic conditions affecting older adults, and is a significant public health problem among adults of working age. The knee is the most frequently involved joint site associated with disability in OA. Diagnosis of OA is primarily based on history and physical examination, but radiographic findings, including asymmetric joint space narrowing (JSN), subchondral sclerosis, osteophyte formation, subluxation, and distribution patterns of osteoarthritic changes are all helpful when diagnosis is uncertain. Structural morphological changes on X-rays are also considered the primary outcome variables for assessing the progression of OA. The development of new methods for prevention and treatment of OA requires improved understanding of the factors that influence its progression. The ability to assess progression quantitatively is a necessary first step in understanding factors that influence the disease process. Depending on the joint studied, several indices are currently used for assessing radiological progression of OA, including individual radiographic features (e.g., marginal osteophytes), composite indices (e.g., Kellgren and Lawrence scoring systems), and quantitative measures (e.g., joint space width measurement). Unfortunately, the review of studies evaluating the longitudinal rate of JSN indicates that the yearly change may be very small and of doubtful clinical significance. This emphasizes the need for further refinement in the definition of radiographic outcomes in prospective clinical trials. This review focuses on the available scoring methods used for the sites most frequently involved in OA (hand, knee, hip) and their various advantages and disadvantages.

Impact of type of meniscal tear on radiographic and symptomatic knee osteoarthritis: a sixteen-year followup of meniscectomy with matched controls

OBJECTIVE

To investigate long-term radiographic and patient-relevant outcome of isolated limited meniscectomy with regard to type of meniscal tear and extent of surgical resection.

METHODS

We studied 155 patients with intact cruciate ligaments (mean +/- SD age 54 +/- 12 years) who had undergone meniscectomy an average of 16 +/- 1 years earlier. The patients were examined using standardized radiography and validated self-administered questionnaires. The Knee Injury and Osteoarthritis Outcome Score (KOOS) was used to quantify knee-related symptoms, and the definition of a symptomatic knee was determined. We used 68 control subjects matched for age, sex, and body mass index to calculate the relative risks (RRs).

RESULTS

Radiographic tibiofemoral osteoarthritis (OA) (Kellgren/Lawrence grade > or =2) was present in 66 index knees (43%), of which 39 (59%) were considered to be symptomatic according to the KOOS. In total, 77 patients (50%) had a symptomatic index knee. In a multivariate model, degenerative meniscal tears were associated with both radiographic OA (P = 0.030) and combined radiographic and symptomatic OA (P < or = 0.015). The RRs for combined radiographic and symptomatic OA after degenerative and traumatic types of meniscal tear were 7.0 (95% confidence interval [95% CI] 2.1-23.5) and 2.7 (95% CI 0.9-7.7), respectively, compared with matched controls.

CONCLUSION

An isolated meniscal tear treated by limited meniscectomy is associated with a high risk of radiographic and symptomatic tibiofemoral OA at 16-year followup. Factors associated with worse outcome were degenerative meniscal lesions and extensive resections. We suggest that degenerative meniscal tears may be associated with incipient OA, and that the meniscal tear signals the first symptom of the disease.

Reliability and validity of the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index in Italian patients with osteoarthritis of the knee

OBJECTIVE

The Western Ontario and McMaster Universities (WOMAC) Osteoarthritis (OA) Index is a tested questionnaire to assess symptoms and physical functional disability in patients with OA of the knee and the hip. We adapted the WOMAC for the Italian language and tested its metric properties in 304 patients with symptomatic OA of the knee.

METHODS

Three hundred and four consecutive patients, attending 29 rheumatologic outpatient clinic in northern, central, and southern Italy, were asked to answer two disease-specific questionnaires (WOMAC and Lequesne algofunctional index) and one generic instrument (Medical Outcomes Study SF-36 Health Survey-MOS SF-36). A sample of 258 patients was readministered the WOMAC 7-10 days after the first visit and the structured interview, which also assessed demographic and other characteristics. Internal consistency was assessed using Cronbach's alpha, reliability using intraclass correlation coefficients (ICCs), and construct and discriminant validity using Spearman's correlations, Wilcoxon rank sum test, and Kruskal-Wallis test.

RESULTS

All WOMAC subscales (pain, stiffness, and physical function) were internally consistent with Cronbach's coefficient alpha of 0.91, 0.81, and 0.84, respectively. Test-retest reliability was satisfactory with ICCs of 0.86, 0.68, and 0.89, respectively. In comparison with the SF-36, the expected correlations were found when comparing items measuring similar constructs, supporting the concepts of convergent construct validity. Very high correlations were also obtained between WOMAC scores and Lequesne OA algofunctional index. WOMAC physical function, but not WOMAC stiffness and pain subscales, was weakly associated with radiological OA severity (P=0.03). Also, WOMAC pain score was inversely correlated (P=0.01) with years of formal education. Examination of discriminant validity showed that the scores on the WOMAC and SF-36 followed hypothesized patterns: the WOMAC discriminated better among subjects with varying severity of knee problems, whereas the SF-36 discriminated better among subjects with varying levels of self-reported health status and comorbidity.

CONCLUSION

The Italian version of WOMAC is a reliable and valid instrument for evaluating the severity of OA of the knee, with metric properties in agreement with the original, widely used version.

Osteoarthritis: MR imaging findings in different stages of disease and correlation with clinical findings

PURPOSE

To determine whether knee pain, stiffness, and limited function in patients with different stages of osteoarthritis correlate with the degree of disease assessed on magnetic resonance (MR) images and radiographs.

MATERIALS AND METHODS

Radiographs in 50 patients with varying degrees of osteoarthritis of the knee were assessed by using the the Western Ontario and McMaster University (WOMAC) osteoarthritis index and the Kellgren-Lawrence (KL) scale. MR images were obtained and analyzed by two readers for cartilage lesions, bone marrow edema pattern, and ligamentous and meniscal lesions.

RESULTS

Thirteen of 16 knees with a KL score of 4 showed full-thickness cartilage lesions and bone marrow edema pattern. Cruciate ligament tears were found in five of 12 knees with a KL score of 3 and in nine of 16 knees with a KL score of 4. While the KL score correlated significantly (P <.05) with the grade of cartilage lesions, and a substantially higher percentage of lesions with higher KL scores were found on MR images, the correlations between MR imaging findings and KL score versus clinical findings were not significant (P >.05). Significant differences between WOMAC scores were found only for the grades of cartilage lesions (P <.05).

CONCLUSION

Cartilage lesions, bone marrow edema pattern, and meniscal and ligamentous lesions were frequently demonstrated on MR images in patients with advanced osteoarthritis. Clinical findings showed no significant correlations with KL score and extent of findings at MR imaging.