Risk Of Osteoarthritis Progression Research Articles

Age and Meniscal Extrusion Are Determining Factors of Osteoarthritis Progression after Conservative Treatments for Medial Meniscus Posterior Root Tear.

With a growing understanding of biomechanical disadvantages following medial meniscus posterior root tear (MMPRT), recent studies have focused on surgical repair of MMPRT. Because not all tears are repairable, surgical indications can be properly established when the outcomes of conservative treatments are revealed. This study tried to identify risk factors for osteoarthritis progression after conservative treatments for isolated MMPRT. Patients who had conservative treatments for isolated MMPRT during 2013-2016 were retrospectively reviewed. To evaluate osteoarthritis progression, those who were followed up for ≤3 years and those who already showed advanced osteoarthritis of Kellgren--Lawrence (K-L) grade 4 at the time of diagnosis were excluded. Because patients with varus malalignment were candidates for realignment osteotomy, conservative treatments for MMPRT were applied to patients with well-aligned knees. Osteoarthritis progression was determined based on the K-L grading system, and risk factors including age, sex, body mass index, lower limb alignment, preoperative K-L grade, meniscal extrusion, and the presence of subchondral bone marrow lesion (BML) were analyzed using logistic regression analyses. A total of 42 patients were followed up for 57.4 ± 26.8 months. During that period, osteoarthritis progression was noted in 17 (40.5%) patients. Based on univariate analyses for each risk factor, age, meniscal extrusion, and the presence of subchondral BML were included in the multivariate logistic regression analysis. The results showed that age (p = 0.028, odds ratio = 0.87) and meniscal extrusion (p = 0.013, odds ratio = 9.65) were significant risk factors. A receiver operating characteristic curve found that the cutoff age was 63.5 years, with the area under the curve being 0.72 (sensitivity, 68.0%; specificity, 70.6%). About two-fifths of patients who had conservative treatments for MMPRT underwent osteoarthritis progression in the mid to long term. Age and meniscal extrusion were determining factors of osteoarthritis progression. The risk for osteoarthritis progression was decreased when the age of patients was over 63.5 years.

The discoid lateral meniscus in children: a narrative review of pathology, diagnosis and treatment.

The discoid lateral meniscus (DLM) is a congenital abnormality of the meniscal shape, characterized by a typical central hypertrophy and a diameter larger than a regular meniscus, potentially leading to knee pain and symptoms, especially in children. The present study provides an update and a general review of this uncommon meniscal pathology. The incidence of discoid meniscus is about 0.4-17% for the lateral and 0.1-0.3% for the medial, although, being often asymptomatic, the true prevalence is unknown. We aim to enhance awareness on this subject to medical care provider. A literature search was performed on PubMed, including articles written in English until October 2021. The articles regarding etiology, diagnosis and management of DLM in children or in patients younger than 18 years were reviewed using the narrative approach. Recent literature has shown that DLM is one of the most frequent congenital anomalies of the knee encountered during childhood. While asymptomatic children with incidental finding can be managed nonoperatively, symptomatic painful DLM should be addressed surgically, restoring typical anatomy using saucerization, tear repair, and stable fixation of the meniscus. The risk of osteoarthritis progression seems to be higher in children with operated DLM, imposing prolonged follow-up and cartilage preserving strategies for these patients.

Pleiotropic effects of diacerein in comorbid patients with osteoarthritis

The article presents an analysis of the therapeutic effect of the drug diacerein (D), which has been used in osteoarthritis (OA) for more than 20 years and is included in the clinical guidelines of the Association of Rheumatologists of Russia (2021) and the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal diseases (ESCEO, 2019) for the treatment of OA. The main pathogenic effect of D in OA is to suppress the synthesis of interleukin 1, stimulate the production of articular cartilage proteoglycans, and slow down abnormal remodeling of the subchondral bone. The advantages of D in the treatment of patients with OA and comorbidities are presented – a prolonged anti-inflammatory and analgesic effect and good tolerability. These properties of D allow to control the symptoms of OA and improve the quality of life of patients. The structure-modifying effect of D is based on its ability to stimulate the synthesis of articular cartilage proteoglycans with long-term use and prevent abnormal remodeling of the subchondral bone, which leads to a decrease in the risk of OA progression and a delay in total joint arthroplasty. An important advantage of D is its positive metabolic effect in patients with type 2 diabetes mellitus and obesity, which is associated with the ability of D to reduce the level of glycated hemoglobin and body mass index. Data are presented on the absence of adverse cardiovascular effects when using D, which allows us to recommend its use in patients with OA who have comorbid cardiovascular diseases, as well as contraindications for non-steroidal anti-inflammatory drugs.

Insall proximal realignment with/without tibial tubercle osteotomy for recurrent patellar instability yields acceptable medium- to long-term results but risk of osteoarthritis progression is considerable

PurposeThe purpose of this study was to evaluate clinical and radiological results in patients operated for recurrent patellar instability with a surgical approach consisting of Insall proximal realignment with/without tibial tubercle osteotomy (TTO).MethodsPatients that underwent surgery for recurrent patellar instability at one centre with a uniform technique between 2004 and 2020 were included. Eligible patients were assessed by clinical examination and the disease-specific Banff Patellofemoral Instability Instrument 2.0 (BPII 2.0). Pre- and postoperative radiographs were analysed for patellofemoral osteoarthritis (OA) according to Iwano. Preoperative Magnetic Resonance Imaging (MRI) and radiographs were analysed for anatomical risk factors for patellar instability. Student t-test, chi-square test and ANOVA-analyses were used to investigate whether anatomical risk factors and/or patient characteristics could predict an inferior outcome.ResultsForty-six patients (47 knees) were included at a mean follow-up time of 6.6 years (SD 4.6; range 1–17). Mean BPII 2.0 score was 60.4 (SD 18.4; range 26–98), and 10.6% (n = 5) had suffered a postoperative redislocation. Progression to evident patellofemoral OA was seen in 15% of the patients (p < 0.05). The presence of pathoanatomic risk factors did not correlate with recurrent postoperative instability or inferior BPII 2.0 score at the final evaluation.ConclusionPatients treated with the current approach reported acceptable medium- to long-term results, but the risk of patellofemoral OA progression is significant. These findings add to the knowledge of expected outcomes after procedures involving Insall proximal realignment, and can guide clinical decision making for surgeons using similar methods.Level of evidenceLevel IV, case series.

Successful Treatment of Femoral Chondral Lesions with a Novel Customized Metal Implant at Midterm Follow-Up.

Full-depth cartilage lesions do not heal spontaneously and may progress to osteoarthritis (OA). Treatment for these lesions is warranted when symptomatic. At younger age, biological treatment remains the gold standard, but treatment in the middle-aged patient remains a clinical challenge and focal metal implants have been proposed. We aim to present the subjective outcome at 2 years and the risk of reoperation for any reason at midterm after surgery with a novel customized implant for focal femoral chondral lesions in the knee. In a prospective cohort study, 30 patients were included between January 2013 and December 2017 at 9 different clinics in Sweden. The primary outcome was subjective outcome measurements (Visual Analogue Scale [VAS], EuroQoL [EQ5D], Knee injury and Osteoarthritis Outcome Score [KOOS]) at a minimum of 2 years. The secondary outcome was reoperations for any reason during the follow-up period until December 2019 (mean of 55 months) studied retrospectively by analyzing medical records. The VAS, EQ5D, and all the KOOS subscales showed significant improvements from preoperatively to the 2-year follow-up. The VAS showed the greatest improvement at the early (3 months) postoperative stage (P < 0.001). Five (7%) patients underwent reoperations and one of these was revised to hemiarthroplasty due to OA progression. No implant loosening was detected in any of the cases. This customized resurfacing metal implant showed good safety and patient satisfaction. The risk of OA progression and implant loosening is low. Subjective function and pain improved significantly.

Gene Expression in Meniscal Tears at the Time of Arthroscopic Partial Meniscectomy Predicts the Progression of Osteoarthritis Within 6 Years of Surgery.

Background:While knees with meniscal tears are associated with a heightened risk of developing osteoarthritis (OA), it is difficult to predict which patients are at the greatest risk for OA. Gene signatures in menisci that are resected during arthroscopic partial meniscectomy (APM) may provide insight into the risk of OA progression.Hypothesis:Meniscal gene signatures at the time of APM will predict radiographic OA progression.Study Design:Case series; Level of evidence, 4.Methods:Meniscal fragments were collected from 38 patients without OA during clinically indicated APM of the medial meniscus. The expression of 28 candidate genes with known roles in cartilage homeostasis, OA, extracellular matrix degradation, and obesity was assessed by quantitative real-time polymerase chain reaction. Weightbearing radiographs obtained before surgery and at final follow-up were graded by a musculoskeletal radiologist using the Kellgren-Lawrence classification of OA. The association of meniscal gene expression at baseline with the progression of radiographic OA was determined.Results:Gene expression and baseline and follow-up radiographic data were available from 31 patients (81.6%) at a mean follow-up of 6.2 ± 1.3 years. Patients without OA progression had significantly higher expression of 7 genes: MMP9 (5.1-fold; P = .002), IL8 (2.9-fold; P = .016), CCL3 (3.7-fold; P = .032), CCL3L1 (4.5-fold; P = .008), CXCL6 (6.2-fold; P = .010), LEP (5.2-fold; P = .004), and RETN (46-fold; P = .008).Conclusion:Gene expression in the meniscus at the time of APM may be associated with the risk for progression of OA after surgery. Elevated expression of the aforementioned genes may reflect a chondroprotective response. Stratifying the risk for OA progression after APM could facilitate targeted interventions to delay or prevent the development of OA. Further studies in a larger cohort with an extended follow-up, and inclusion of additional genes, are warranted to better characterize this association.

Gene expression in meniscus tears at the time of arthroscopic partial meniscectomy predicts osteoarthritis progression

Objectives:While meniscus tears are associated with an increased risk of developing knee osteoarthritis (OA), it is not possible to predict which patients are at the highest risk for developing OA. Gene signature in meniscus resected at the time of arthroscopic partial meniscectomy may provide insight into an individual’s risk of OA progression. The purpose of this study is to test the hypothesis that gene signatures at the time of arthroscopic partial meniscectomy predict radiographic progression of OA.Methods:Meniscus fragments were collected from 40 patients at the time of clinically indicated isolated arthroscopic partial medial meniscectomy. Gene expression was assessed by quantitative real-time PCR using a panel of 28 candidate genes with known roles in cartilage homeostasis, OA, extracellular-matrix degradation and obesity. Radiographs obtained prior to surgery and at final follow-up were graded by a musculoskeletal radiologist. The association of meniscus gene expression at the time of surgery with progression of radiographic OA was determined.Results:Gene expression in meniscus resected at arthroscopic partial medial meniscectomy and radiographic data at baseline and mean follow-up of 6.2 ± 1.3 years were available for 31 patients (77.5%). The cohort consisted of 45.2% females with a mean age of 48.5 ± 9.2 years and mean body mass index of 28.1 ± 5.1 kg/m2. Gene expression was associated with radiographic progression of OA (Table 1). Patients without OA progression had significantly higher expression of seven genes, namely MMP9 (5.1-fold, P=0.002), IL8 (2.9-fold, P=0.016), CCL3 (3.7-fold, P=0.032), CCL3L1 (4.5-fold, P=0.008), CXCL6 (6.2-fold, P=0.010), LEP (5.2-fold, P=0.004) and RETN (46-fold, P=0.008). Patients with progression showed very low expression of these genes (Figure 1). When segregating patients based on severity of OA progression, there was significantly increased expression of three genes (MMP9, CXCL6, LEP) among patients without any radiographic OA progression. There was an increased expression of CXCL6 (9.5-fold, P=0.042), LEP (4.3-fold, P=0.047) and MMP9 (5.0-fold, P=0.023) among those without any radiographic OA progression compared to those with rapid progression in the medial compartment. There was also an increased expression of MMP9 among patients without progression compared to those with progression in the lateral and/or patellofemoral compartments (7.2-fold, P=0.038).Conclusions:Our findings suggest that gene expression in the meniscus at the time of arthroscopic partial meniscectomy is associated with the risk for OA progression. Elevated expression of the aforementioned genes in non-progressors may reflect a potentially chondroprotective response. Further studies including additional genes, larger cohorts and extended follow-up are warranted to better characterize this association. Ultimately, this line of investigation could facilitate the development of more sensitive methods to determine the risk for OA progression among patients with meniscal injury and approaches to delay or prevent OA in this population.

Chondrocalcinosis of the Knee and the Risk of Osteoarthritis Progression: Data From the Knee and Hip Osteoarthritis Long-term Assessment Cohort.

To assess the impact of knee chondrocalcinosis (CC) on the 5-year risk of joint replacement and disease progression in patients with knee osteoarthritis (OA). Patients with symptomatic knee OA without previous total joint (knee or hip) replacement (TJR) were recruited from the Knee and Hip Osteoarthritis Long-term Assessment cohort. Cox proportional hazards regression and generalized estimating equation models were used to compare the time from inclusion or OA diagnosis to total knee replacement (TKR) or TJR between patients with and those without knee CC at inclusion. In patients without incident TKR, logistic regression was performed to examine the association between CC and radiographic progression (Kellgren/Lawrence [K/L] grade) or worsening of Western Ontario and McMaster Universities Arthritis Index (WOMAC) subscores for OA pain or function between years 0 and 5. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were estimated. Analyses were adjusted for age, sex, body mass index, WOMAC subscores, and K/L grade. Among the 656 patients included, 93 (14.2%) had knee CC, and 91 (13.9%) underwent TKR during the follow-up. Risk of TKR was not affected by the presence of knee CC (HR 1.26 [95% CI 0.74-2.17]). Similar results were obtained for the risk of incident TJR. For patients without incident TKR, knee CC did not affect the risk of worsening of K/L grade (odds ratio [OR] 0.9 [95% CI 0.4-1.7]), WOMAC pain subscore (OR 1.1 [95% CI 0.7-1.4]), or WOMAC function subscore (OR 0.9 [95% CI 0.4-2.0]). In patients with symptomatic knee OA, the presence of knee CC did not affect the risk of arthroplasty or disease progression at 5 years.

Progressive osteoarthritis during pregnancy several years following hip arthroscopy for femoroacetabular impingement

CaseA 28-year-old with borderline left hip dysplasia who underwent arthroscopic acetabuloplasty, femoral osteochondroplasty, and labral repair for femoroacetabular impingement. She did well for 8 years, though required arthroscopic capsulolabral adhesion release 2 years after the initial procedure. After this period of stability, she developed left hip pain during pregnancy. Radiographs demonstrated progressive osteoarthritis that lead to total hip arthroplasty at age 37. ConclusionThe physiologic and hormonal changes during pregnancy leading to increased ligamentous laxity may put vulnerable patients with hip dysplasia and iatrogenic instability at increased risk for progression of osteoarthritis.

The risk of osteoarthritis progression after arthroscopic partial meniscectomy (APM); data from an rct of APM vs. physical therapy

The risk of osteoarthritis progression after arthroscopic partial meniscectomy (APM); data from an rct of APM vs. physical therapy

Molecular Analysis of Age and Sex-Related Gene Expression in Meniscal Tears with and without a Concomitant Anterior Cruciate Ligament Tear

The meniscus plays critical roles in the knee, contributing to load transmission, shock absorption, and joint stability. Little is known about gene expression in meniscal tears, particularly in relation to injury pattern and patient age and sex. The purpose of this study was to test the hypothesis that gene expression in meniscal tears varies depending on patient age and sex and whether the anterior cruciate ligament (ACL) is also torn. Meniscal tissue from twenty-eight patients with an isolated meniscal tear or a meniscal tear with a concomitant ACL tear was collected at the time of clinically indicated partial meniscectomy. Messenger RNA (mRNA) expression was examined by quantitative real-time polymerase chain reaction for molecular markers of osteoarthritis including proinflammatory cytokines (interleukin [IL]-1α, IL-1β, IL-6, and tumor necrosis factor-alpha [TNFα]), chemokines (IL-8, CCL3, CCL3L1, CXCL1, CXCL3, CXCL6, and CCL20), aggrecanases (ADAMTS-4 [a disintegrin and metalloproteinase with thrombospondin type-4 motifs] and ADAMTS-5), matrix metalloproteinases (MMP-1, MMP-3, MMP-9, and MMP-13), transcription factors (NFκB2 [nuclear factor kappa B2], NFκBIA [NF-kappa B inhibitor alpha], and IκBA [inhibitor of kappa B alpha]), and matrix components (bone morphogenetic protein [BMP]-2, type-I collagen alpha 1 [Col1a1], Col2a1, and aggrecan). Expression of IL-1β (p = 0.02), ADAMTS-5 (p = 0.001), MMP-1 (p = 0.007), MMP-9 (p = 0.002), MMP-13 (p = 0.01), and NFκB2 (p = 0.01) was significantly higher in patients with a meniscal tear who were under the age of forty years than it was in those over the age of forty years. Similarly, the expression of ADAMTS-4 (p = 0.002), ADAMTS-5 (p = 0.02), MMP-1 (p = 0.02), and MMP-13 (p = 0.0002) was higher in patients with a meniscal tear and an ACL tear who were under the age of forty years than it was in those over forty years. In patients with a meniscal tear and an ACL tear, the expression of IL-1β (p = 0.01), TNFα (p = 0.02), MMP-13 (p = 0.004), CCL3 (p = 0.03), and CCL3L1 (p = 0.03) was significantly higher, while that of aggrecan (p = 0.03) was lower, than that in patients with a meniscal tear alone. The only sex-based difference in gene expression was higher levels of CCL3L1 in female patients (p &lt; 0.05) of all ages with combined injuries. These findings suggest clinically relevant differences in the response of the knee to meniscal tears on the basis of patient age and sex. Elevated expression levels of arthritis-related markers indicate an increased catabolic response in patients under forty years old. Higher expression of catabolic markers in patients with meniscal and ACL tears suggests this combined injury pattern is more likely to lead to the development of osteoarthritis. Catabolic activity in meniscal tissue may predict patients who are at risk for progression of osteoarthritis following partial meniscectomy.

Sit-to-Stand 3 months after unilateral total knee arthroplasty: Comparison of self-selected and constrained conditions

After unilateral total knee arthroplasty (TKA), rehabilitation specialists often constrain knee angles or foot positions during sit-to-stand, to encourage increased weight bearing through the operated limb. Biomechanical studies often constrain limb position during sit-to-stand in an effort to reduce variability. Differences between self-selecting or constraining position are unknown in persons after TKA. Twenty-six subjects with unilateral TKA participated in motion analysis. Subjects performed the sit-to-stand using a self-selected position (ssSTS); next, trials were collected in a constrained condition (ccSTS), where both knees were positioned with the tibia vertical, perpendicular to the floor. Repeated measures ANOVA (limb × condition) assessed differences between limbs and between conditions. Subjects used greater hip flexion bilaterally during ccSTS (91°) compared to ssSTS (87°; p = 0.001) and knee flexion on the non-operated limb was greater during ssSTS (84°) compared to ccSTS (82°; p = 0.018). The ccSTS resulted in larger extensor moments on the non-operated limb at the hip (ssSTS −0.473, ccSTS −0.521; p = 0.021) and knee (ssSTS −0.431, ccSTS −0.457; p = 0.001) compared to the operated limb. The ccSTS exacerbated the asymmetries at the hip and knee compared to ssSTS, and did not improve use of the operated limb. Reliance on the non-operated limb may put them at risk for progression of osteoarthritis in other joints of the lower extremities.

Is obesity a risk factor for progressive radiographic knee osteoarthritis?

To examine whether obesity increases the risk of progression of knee osteoarthritis (OA). We used data from the Multicenter Osteoarthritis Study, a longitudinal study of persons with or at high risk of knee OA. OA was characterized at baseline and 30 months using posteroanterior fixed-flexion radiographs and Kellgren/Lawrence (K/L) grading, with alignment assessed on full-extremity films. In knees with OA at baseline (K/L grade 2 or 3), progression was defined as tibiofemoral joint space narrowing on the 30-month radiograph. In knees without OA at baseline (K/L grade 0 or 1), incident OA was defined as the development of radiographic OA at 30 months. Body mass index (BMI) at baseline was classified as normal (<25 kg/m(2)), overweight (25-<30 kg/m(2)), obese (30-<35 kg/m(2)), and very obese (>or=35 kg/m(2)). The risk of progression was tested in all knees and in subgroups categorized according to alignment. Analyses were adjusted for age, sex, knee injury, and bone density. Among the 2,623 subjects (5,159 knees), 60% were women, and the mean +/- SD age was 62.4 +/- 8.0 years. More than 80% of subjects were overweight or obese. At baseline, 36.4% of knees had tibiofemoral OA, and of those, only one-third were neutrally aligned. Compared with subjects with a normal BMI, those who were obese or very obese were at an increased risk of incident OA (relative risk 2.4 and 3.2, respectively [P for trend < 0.001]); this risk extended to knees from all alignment groups. Among knees with OA at baseline, there was no overall association between a high BMI and the risk of OA progression; however, an increased risk of progression was observed among knees with neutral but not varus alignment. The effect of obesity was intermediate in those with valgus alignment. Although obesity was a risk factor for incident knee OA, we observed no overall relationship between obesity and the progression of knee OA. Obesity was not associated with OA progression in knees with varus alignment; however, it did increase the risk of progression in knees with neutral or valgus alignment. Therefore, weight loss may not be effective in preventing progression of structural damage in OA knees with varus alignment.

Association between valgus and varus alignment and the development and progression of radiographic osteoarthritis of the knee

Although knee malalignment is assumed to correlate with knee osteoarthritis (OA), it is still unknown whether malalignment precedes the development of OA or whether it is a result of OA. The aim of this study was to assess the relationship between malalignment and the development of knee OA as well as progression of knee OA. A total of 1,501 participants in the Rotterdam study were randomly selected. Knee OA at baseline and at followup (mean followup 6.6 years) was scored according to the Kellgren/Lawrence (K/L) grading system. Alignment was measured by the femorotibial angle on radiographs at baseline. Multivariable logistic regression for repeated measurements was used to analyze the association of malalignment with the development and progression of OA. Of 2,664 knees, 1,012 (38%) were considered to have normal alignment, 693 (26%) had varus alignment, and 959 (36%) had valgus alignment. A comparison of valgus alignment and normal alignment showed that valgus alignment was associated with a borderline significant increase in development of knee OA (odds ratio [OR] 1.54, 95% confidence interval [95% CI] 0.97-2.44), and varus alignment was associated with a 2-fold increased risk (OR 2.06, 95% CI 1.28-3.32). Stratification for body mass index showed that this increased risk was especially seen in overweight and obese individuals but not in non-overweight persons. The risk of OA progression was also significantly increased in the group with varus alignment compared with the group with normal alignment (OR 2.90, 95% CI 1.07-7.88). An increasing degree of varus alignment is associated not only with progression of knee OA but also with development of knee OA. However, this association seems particularly applicable to overweight and obese persons.

Thrust during ambulation and the progression of knee osteoarthritis

To determine whether the presence of varus thrust at baseline increases the risk of progression of medial tibiofemoral osteoarthritis (OA), whether knees with thrust have a greater adduction moment, whether thrust has any additional impact on top of static varus, and whether thrust is associated with poor physical function outcome. Two hundred thirty-seven patients with knee OA (definite osteophytes and symptoms) underwent baseline gait observation to assess varus thrust and full-limb radiography to assess alignment. Sixty-four of these 237 patients also underwent quantitative gait analysis to determine the maximum knee adduction moment. Two hundred thirty patients (97%) returned for followup at 18 months. At baseline and 18 months, the 230 participants had semiflexed, fluoroscopically confirmed knee radiographs (with progression defined as worsening of medial joint space grade); self-reported and performance-based measures of function were also assessed. Logistic regression with generalized estimating equations was used to estimate odds ratios (ORs) for medial OA progression, after excluding knees that were not at risk for progression. Varus thrust was present in 67 of 401 knees. Thrust increased 4-fold (age-, sex-, body mass index-, and pain-adjusted OR 3.96, 95% confidence interval [95% CI] 2.11-7.43) the odds of medial progression, with some reduction after further adjustment for varus alignment severity. In varus-aligned knees, thrust increased the odds of OA progression 3-fold (adjusted OR 3.17, 95% CI 1.60-6.31). In the gait substudy, the adduction moment was greater in knees with a thrust compared with knees without a thrust. Having a thrust in both knees versus neither knee was associated with a 2-fold increase in the OR for poor physical function outcome (P not significant). Varus thrust is a potent risk factor, identifiable by simple gait observation, for disease progression in the medial compartment, the most common site of OA involvement at the knee. Varus thrust may also predict poor physical function outcome. Varus thrust increased the odds of progression among varus-aligned knees considered separately, suggesting that knees with a thrust are a subset of varus-aligned knees at particularly high risk for progression of OA.

Relation of Dietary Intake and Serum Levels of Vitamin D to Progression of Osteoarthritis of the Knee among Participants in the Framingham Study

Evidence suggests that pathophysiologic processes in bone are important determinants of outcome in osteoarthritis of the knee. Low intake and low serum levels of vitamin D may compromise favorable responses of bone to osteoarthritis, predisposing patients to progression. To determine whether dietary intake and serum levels of vitamin D would predict the incidence and progression of osteoarthritis of the knee in participants of the Framingham Study. Prospective observational study. The Framingham Study. Participants in the Framingham Heart Study who had knee radiography at examinations 18 (done between 1983 and 1985) and 22 (done between 1992 and 1993) and received interim assessments of vitamin D intake and serum levels. Intake of vitamin D and serum levels of 25-hydroxyvitamin D, calculated on the basis of dietary habits and supplement use as reported on a questionnaire, were evaluated at examination 20 (1988 to 1989). Knee radiographs were given scores for global severity of osteoarthritis, using a modification of the scale of Kellgren and Lawrence (range, 0 to 4), and for the presence of osteophytes and joint-space narrowing (range, 0 to 3). Covariates measured at examinations 18 and 20 were age, sex, body mass index, weight change, injury, physical activity, health status, bone mineral density, and energy intake. 556 participants (mean age at baseline +/- SD, 70.3 +/- 4.5 years) had complete assessments. Incident osteoarthritis occurred in 75 knees; progressive osteoarthritis occurred in 62 knees. Serum levels of vitamin D were modestly correlated with vitamin D intake (r = 0.24). Risk for progression increased threefold in participants in the middle and lower tertiles for both vitamin D intake (odds ratio for the lower compared with the upper tertile, 4.0 [95% Cl, 1.4 to 11.6]) and serum levels of vitamin D (odds ratio for the lower compared with the upper tertile, 2.9[Cl, 1.0 to 8.2]). Low serum levels of vitamin D also predicted loss of cartilage, as assessed by loss of joint space (odds ratio, 2.3 [Cl, 0.9 to 5.5]) and osteophyte growth (odds ratio, 3.1 [Cl, 1.3 to 7.5]). Incident osteoarthritis of the knee occurring after baseline was not consistently related to either intake or serum levels of vitamin D. Low intake and low serum levels of vitamin D each appear to be associated with an increased risk for progression of osteoarthritis of the knee.

Do antioxidant micronutrients protect against the development and progression of knee osteoarthritis?

Cumulative damage to tissues, mediated by reactive oxygen species, has been implicated as a pathway that leads to many of the degenerative changes associated with aging. We hypothesized that increased intake of antioxidant micronutrients might be associated with decreased rates of osteoarthritis (OA) in the knees, a common age-related disorder. Participants in the Framingham Osteoarthritis Cohort Study underwent knee evaluations by radiography at examinations 18 (1983-1985) and 22 (1992-1993). Usual dietary intake was assessed using the Food Frequency Questionnaire, administered at examination 20 (1988-1989). Knees without OA at baseline (Kellgren and Lawrence [K&L] grade < or = 1) were classified as having incident OA if they had a K&L grade > or = 2 at followup. Knees with OA at baseline were classified as having progressive OA if their score increased by > or = 1 at followup. Knees were also classified as having cartilage loss or osteophyte growth if their maximal joint space narrowing or osteophyte growth score increased by > or = 1 (range 0-3). The association of vitamin C, beta carotene, and vitamin E intake, ranked in sex-specific tertiles, with incidence and progression of OA was compared with that of a panel of nonantioxidant vitamins, Bl, B6, niacin, and folate, using logistic regression and generalized estimation equations to adjust for correlation between fellow knees. The lowest tertile for each dietary exposure was used as the referent category. Odds ratios (OR) were adjusted for age, sex, body mass index, weight change, knee injury, physical activity, energy intake, and health status. Six hundred forty participants received complete assessments. Incident and progressive OA occurred in 81 and 68 knees, respectively. We found no significant association of incident OA with any nutrient. A 3-fold reduction in risk of OA progression was found for both the middle tertile (adjusted OR = 0.3, 95% confidence interval [95% CI] 0.1-0.8) and highest tertile (adjusted OR = 0.3, 95% CI 0.1-0.6) of vitamin C intake. This related predominantly to a reduced risk of cartilage loss (adjusted OR = 0.3, 95% CI 0.1-0.8). Those with high vitamin C intake also had a reduced risk of developing knee pain (adjusted OR = 0.3, 95% CI 0.1-0.8). A reduction in risk of OA progression was seen for beta carotene (adjusted OR = 0.4, 95% CI 0.2-0.9) and vitamin E intake (adjusted OR = 0.7, 95% CI 0.3-1.6), but was less consistent. No significant associations were observed for the nonantioxidant nutrients. High intake of antioxidant micronutrients, especially vitamin C, may reduce the risk of cartilage loss and disease progression in people with OA. We found no effect of antioxidant nutrients on incident OA. These preliminary findings warrant confirmation.