Knee Alignment Is Quantitatively Related to Periarticular Bone Morphometry and Density, Especially in Patients With Osteoarthritis

OBJECTIVE

Static alignment influences knee loading and predicts osteoarthritis (OA) progression. Periarticular bone is important in dispersing forces across the knee, and there is substantial evidence for molecular crosstalk between cartilage and subchondral bone. The aim of this study was to evaluate the relationship between periarticular trabecular bone morphology and bone mineral density (BMD) and knee alignment in OA.

METHODS

This was a cross-sectional analysis of participants in the Osteoarthritis Initiative Bone Ancillary Study. Dual x-ray absorptiometry (DXA) was performed to measure tibial periarticular bone mineral density (paBMD). Magnetic resonance imaging of knee trabecular bone was performed to calculate the apparent bone volume fraction (aBVF), apparent trabecular number (aTbN), apparent trabecular spacing (aTbSp), and apparent trabecular thickness (aTbTh). Static alignment was assessed by measuring the hip-knee-ankle (HKA) angle on long-limb films.

RESULTS

The study group comprised 436 participants (mean ± SD age 65.4 ± 9.2 years, 46% female, mean ± SD body mass index 29.6 ± 4.6 kg/m² ), 71% of whom had OA. Correlations between the HKA angle and medial:lateral paBMD, medial paBMD, aBVF, aTbN, aTbTh, and aTbSp were -0.63, -0.34, -0.29, -0.32, -0.22, and 0.30, respectively. More varus alignment was associated with higher medial:lateral paBMD, medial paBMD, aBVF, aTbN, aTbTh, and lower aTbSp. In OA knees, the results were more pronounced. In non-OA knees, the most consistent association was with medial:lateral paBMD.

CONCLUSION

Static alignment was associated with medial:lateral paBMD in all knees and with medial paBMD and trabecular morphometry in OA knees only. Aberrant knee loading may lead to increased relative subchondral bone density, which is partly related to a higher aBVF and a greater number of thicker trabeculae with smaller intertrabecular spacing. Knee DXA may be a useful early biomarker of knee OA.

Inflammation and glucose homeostasis are associated with specific structural features among adults without knee osteoarthritis: a cross-sectional study from the osteoarthritis initiative

Background

Greater age and body mass index are strong risk factors for osteoarthritis (OA). Older and overweight individuals may be more susceptible to OA because these factors alter tissue turnover in menisci, articular cartilage, and bone via altered glucose homeostasis and inflammation. Understanding the role of inflammation and glucose homeostasis on structural features of early-stage OA may help identify therapeutic targets to delay or prevent the onset of OA among subsets of adults with these features. We examined if serum concentrations of glucose homeostasis (glucose, glycated serum protein [GSP]) or inflammation (C-reactive protein [CRP]) were associated with prevalent knee bone marrow lesions (BMLs) or effusion among adults without knee OA.

Methods

We conducted a cross-sectional study using baseline data from the Osteoarthritis Initiative. We selected participants who had no radiographic knee OA but were at high risk for knee OA. Blinded staff conducted assays for CRP, GSP, and glucose. Readers segmented BML volume and effusion using semi-automated programs. Our outcomes were prevalent BML (knee with a BML volume > 1 cm³) and effusion (knee with an effusion volume > 7.5 cm³). We used logistic regression models with CRP, GSP, or glucose concentrations as the predictors. We adjusted for age, sex, body mass index (BMI), and Physical Activity Scale for the Elderly (PASE) scores.

Results

We included 343 participants: mean age = 59 ± 9 years, BMI = 27.9 ± 4.5 kg/m², PASE score = 171 ± 82, and 64% female. Only CRP was associated with BML prevalence (odds ratio [OR] = 1.43, 95% confidence interval [CI] = 1.09 to 1.87). For effusion, we found an interaction between BMI and CRP: only among adults with a BMI <25 kg/m² was there a significant trend towards a positive association between CRP and effusion (OR = 1.40, 95% CI = 1.00 to 1.97). We detected a U-shaped relationship between GSP and effusion prevalence. Fasting glucose levels were not significantly associated with the presence of baseline effusion or BML.

Conclusions

Among individuals without knee OA, CRP may be related to the presence of BMLs and effusion among normal weight individuals. Abnormal GSP may be associated with effusion. Future studies should explore whether inflammation and glucose homeostasis are predictive of symptomatic knee OA.

The associations between radiographic hand osteoarthritis definitions and hand pain: data from the osteoarthritis initiative

The goal of our study was to evaluate the associations between various definitions of radiographic hand osteoarthritis (OA) and self-reported hand pain. We conducted a cross-sectional study with 3604 participants from the Osteoarthritis Initiative (OAI). Posteroanterior radiographs of the dominant hand were read using a modified Kellgren-Lawrence (KL) scale. For our primary analysis, hand OA at person level was defined as two or more finger joints with KL grade 2 or higher. In addition, for the purpose of exploratory analyses, we explored more conservative definitions of hand OA as well as different sum scores and digit- and row-based scores. The majority of definitions of radiographic hand OA were statistically significantly associated with self-reported hand pain. In our main analysis, persons with two or more finger joints with KL grade > 2 were approximately two times more likely to self-report hand pain than persons without radiographic hand OA. Increasing KL grades and increasing number of joints affected lead to stronger associations. Almost all definitions of hand OA were related to pain. Individuals with more severely affected joints or with higher number of affected joints are more likely to report hand pain than their peers. Specifically, individuals with hand joints with KL 3 or 4 have the greatest likelihood of hand pain.

Subjective Crepitus as a Risk Factor for Incident Symptomatic Knee Osteoarthritis: Data From the Osteoarthritis Initiative

OBJECTIVE

Subjective crepitus is the reporting of hearing grating, cracking, or popping sounds in and/or around a joint. We aimed to evaluate whether there is an association between crepitus and incident symptomatic knee osteoarthritis (OA) in the Osteoarthritis Initiative (OAI), a multicenter longitudinal US cohort.

METHODS

Knees without baseline symptomatic OA were included. Crepitus frequency was assessed using a question from the Knee Injury and Osteoarthritis Outcome Score at baseline and at 12, 24, and 36 months. Frequent knee pain and radiographs were assessed at baseline and at annual visits up to 48 months. Radiographic OA was defined as a tibiofemoral Kellgren/Lawrence grade ≥2. Symptomatic OA was defined as a knee with both frequent symptoms and radiographic OA. We performed a repeated-measures analysis with a predictor of crepitus and outcome of incident symptomatic OA, adjusting for age, sex, and body mass index (BMI), with those never reporting crepitus as the referent group.

RESULTS

There were a total of 3,495 participants (42.2% male), with mean ± SD age of 61.1 ± 9.2 years and a mean ± SD BMI of 28.2 ± 4.7 kg/m². The odds of incident symptomatic OA were higher with greater frequency of crepitus (never, rarely, sometimes, often, and always, with adjusted odds ratios of (referent), 1.5, 1.8, 2.2, and 3.0, respectively; P < 0.0001 for trend). The group with radiographic OA at OAI baseline but without symptoms contributed 26% of the observations but more than 75% of the incident symptomatic OA cases.

CONCLUSION

In those without symptomatic OA, subjective knee crepitus predicts incident symptomatic OA longitudinally, with most cases occurring in those with preexisting tibiofemoral radiographic OA but without frequent knee pain. However, an important limitation is that patellofemoral OA was not systematically evaluated within the OAI. Subjective crepitus offers utility for the identification of at-risk individuals, predictive modeling, and future research.

Glucose homeostasis influences the risk of incident knee osteoarthritis: Data from the osteoarthritis initiative

We aimed to determine if serum measures of impaired glucose homeostasis (glucose concentrations or glycated serum protein, GSP) or systemic inflammation (high-sensitivity C-reactive protein, CRP) are related to incident typical knee osteoarthritis (KOA) or incident accelerated KOA. We conducted a case-control study using the Osteoarthritis Initiative's baseline and first four annual visits. All participants had no radiographic KOA at baseline (Kellgren-Lawrence [KL] < 2). We classified three groups: (i) incident accelerated KOA: >1 knee developed advance-stage KOA (KL Grade 3 or 4) within 48 months; (ii) incident typical KOA: > 1 knee increased in radiographic scoring within 48 months (excluding those with accelerated KOA); and (iii) No KOA: no change in KL grade by 48 months. We matched on sex. A laboratory blinded to group assignment used baseline serum samples to conduct assays for CRP, GSP, and glucose. Due to nonlinear relationships, we used three piece-wise multinomial logistic regression models to determine if baseline CRP, GSP, or glucose were associated with incident typical KOA or accelerated KOA compared with no KOA. We adjusted for age, body mass index, and sex. We analyzed 54 adults/group. Lower and higher GSP concentrations were associated with incident typical KOA compared with adults with concentrations (log) closer to 5.7 (lnGSp < 5.7: OR = 0.28, 95%CI = 0.08-0.93; lnGSp > 5.7: OR = 3.21, 95%CI = 1.07-9.62). Glucose, GSP, and CRP were not significantly associated with incident accelerated KOA. Glucose homeostasis may predict individuals at risk of incident typical KOA but not accelerated KOA, which may indicate accelerated KOA is a distinct disorder from typical KOA. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2282-2287, 2017.

Effects of Tai Chi versus Physical Therapy on Mindfulness in Knee Osteoarthritis

Tai Chi mind-body exercise is widely believed to improve mindfulness through incorporating meditative states into physical movements. A growing number of studies indicate that Tai Chi may improve health in knee osteoarthritis (OA), a chronic pain disease and a primary cause of global disability. However, little is known about the contribution of mindfulness to treatment effect of Tai Chi practice. Therefore, our purpose was to investigate the effect of Tai Chi mind-body practice compared to physical therapy (PT) on mindfulness in knee OA. Adults with radiographic-confirmed, symptomatic knee OA were randomized to either 12 weeks (twice weekly) of Tai Chi or PT. Participants completed the Five Facet Mindfulness Questionnaire (FFMQ) before and after intervention along with commonly-used patient-reported outcomes for pain, physical function, and other health-related outcomes. Among 86 participants (74% female, 48% white, mean age 60 years, 85% at least college educated), mean total FFMQ was 142±17. Despite substantial improvements in pain, function, and other health-related outcomes, each treatment group's total FFMQ did not significantly change from baseline (Tai Chi= 0.76, 95% CI: -2.93, 4.45; PT= 1.80, 95% CI: -2.33, 5.93). The difference in total FFMQ between Tai Chi and PT was not significant (-1.04 points, 95% CI: -6.48, 4.39). Mindfulness did not change after Tai Chi or PT intervention in knee OA, which suggests that Tai Chi may not improve health in knee OA through cultivating mindfulness. Further study is needed to identify underlying mechanisms of effective mind-body interventions among people with knee OA.

Patterns of intra-articular injection use after initiation of treatment in patients with knee osteoarthritis: data from the osteoarthritis initiative

OBJECTIVE

We sought to describe and evaluate longitudinal use of intra-articular injections after treatment initiation among adults with radiographically confirmed knee osteoarthritis (OA).

METHOD

Using data from the Osteoarthritis Initiative (OAI), we included participants with radiographically confirmed OA (Kellgren-Lawrence grade (K-L) ≥ 2) in ≥1 knee at baseline. With 9 years of data, 412 participants newly initiating hyaluronic acid or corticosteroid injections with their index visit were identified. For each type of injection initiated, socio-demographic and clinical characteristics were described by patterns of treatments (one-time use, switched, or continued injections). Multinomial logistic models estimated the extent to which patient-reported symptoms (post-initial injection and changes over time) were associated with patterns of injection use.

RESULTS

Of those initiating injections, ∼19% switched, ∼21% continued injection type, and ∼60% did not report any additional injections. For participants initiating corticosteroid injections, greater symptoms post-initial injection were associated with lower odds of continued use compared to one-time users (adjusted odds ratio (aOR) for Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain: 0.91; 95%, confidence interval (CI): 0.83 to 0.99; aORstiffness: 0.77; CI: 0.63 to 0.94; aORphysical function: 0.97; CI: 0.94 to 1.00). Symptom changes over time (e.g., worsened or improved) were not associated with patterns of injections use.

CONCLUSION

After treatment initiation, the proportion of patients switching injection use and one-time users was substantial. Symptoms post-initial injection appear to be associated with patterns of injection use. The extent to which these patterns are an indication of lack of impact on patient-reported symptoms should be explored.

Responsiveness and Minimally Important Differences for 4 Patient-Reported Outcomes Measurement Information System Short Forms: Physical Function, Pain Interference, Depression, and Anxiety in Knee Osteoarthritis

Patient-Reported Outcomes Measurement Information System (PROMIS) instruments can provide valid, interpretable measures of health status among adults with osteoarthritis (OA). However, their ability to detect meaningful change over time is unknown. We evaluated the responsiveness and minimally important differences (MIDs) for 4 PROMIS Short Forms: Physical Function, Pain Interference, Depression, and Anxiety. We analyzed adults with symptomatic knee OA from our randomized trial comparing Tai Chi and physical therapy. Using baseline and 12-week scores, responsiveness was evaluated according to consensus standards by testing 6 a priori hypotheses of the correlations between PROMIS and legacy change scores. Responsiveness was considered high if ≥5 hypotheses were confirmed, and moderate if 3 or 4 were confirmed. MIDs were evaluated according to prospective change for people achieving previously-established MID on legacy comparators. The lowest and highest MIDs meeting a priori quality criteria formed a MID range for each PROMIS Short Form. Among 165 predominantly female (70%) and white (57%) participants, mean age was 61 years and body mass index was 33. PROMIS Physical Function had 5 confirmed hypotheses and Pain Interference, Depression, and Anxiety had 3 or 4. MID ranges were: Depression = 3.0 to 3.1; Anxiety = 2.3 to 3.4; Physical Function = 1.9 to 2.2; and Pain Interference = 2.35 to 2.4. PROMIS Physical Function has high responsiveness, and Depression, Anxiety, and Pain Interference have moderate responsiveness among adults with knee OA. We established the first MIDs for PROMIS in this population, and provided an important standard of reference to better apply or interpret PROMIS in future trials or clinical practice.

PERSPECTIVE

This study examined whether PROMIS Short Form instruments (Physical Function, Pain Interference, Depression, and Anxiety) were able to detect change over time among adults with knee OA, and provided minimally important change estimates for each measure. This standard of reference can help apply or interpret these instruments in the future.

Risk of Knee Osteoarthritis Over 24 Months in Individuals Who Decrease Walking Speed During a 12-Month Period: Data from the Osteoarthritis Initiative

OBJECTIVE

To assess the association between change in walking speed over a 12-month period and risk of developing radiographic knee osteoarthritis (rKOA) over a 24-month period.

METHODS

We included participants without rKOA from the Osteoarthritis Initiative. Change in walking speed was determined from a 20-m walk assessment, calculated using walking speed at 12-month followup minus baseline speed and/or 24-month followup walking speed minus 12-month speed. Incident rKOA was defined as progressing to Kellgren-Lawrence arthritis grading scale ≥ 2 within 24 months (i.e., incidence between 12 and 36 mos or 24 and 48 mos). Self-reported significant knee injury during the exposure period, age, body mass index (BMI), and Physical Activity Scale for the Elderly (PASE) score were adjusted for analytically.

RESULTS

We included 2638 observations among 1460 unique participants (58% women; aged 59 ± 9 yrs, range 45-79). The mean change in walking speed over 12 months was 0.001 ± 0.13 m/s (range -0.6271 to 1.4968). About 5% of the sample (n = 122) developed rKOA over a 24-month period. After controlling for significant knee injury, age, BMI, and PASE score, we found an 8% relative increase in risk of developing rKOA for every 0.1 m/s decrease in walking speed over a 12-month period (risk ratio 1.08, 95% CI 1.00-1.15, p = 0.05).

CONCLUSION

Evaluating change in speed over a 12-month period using a 20-m walk test may be useful in identifying individuals at increased risk of developing rKOA over the subsequent 24 months. Identification of patients at high risk for developing rKOA would allow medical providers to implement early interventions to maximize joint health.

Walking Speed As a Potential Indicator of Cartilage Breakdown Following Anterior Cruciate Ligament Reconstruction

OBJECTIVE

To determine whether or not self-selected walking speed associates with serum biomarkers of cartilage (collagen and proteoglycan) breakdown in anterior cruciate ligament reconstructed (ACLR) individuals.

METHODS

Twenty individuals with a history of a primary unilateral ACLR participated in this cross-sectional study. Resting blood was collected from each participant prior to completing 5 walking gait trials at a self-selected comfortable speed. Walking speed was evaluated in a 3-dimensional motion capture laboratory and determined from the velocity of the pelvic center of mass. Sera were assessed for collagen type II cleavage product (C2C) and proteoglycan (aggrecan) concentrations using commercially available specific enzyme-linked immunosorbent assays. Pearson's product-moment (r) and Spearman's (ρ) correlations were used to evaluate associations between walking speed and biomarkers of cartilage breakdown metabolism. Partial correlations were used to determine whether covariates influenced associations between walking speed and biomarkers of cartilage breakdown.

RESULTS

ACLR individuals with a slower walking speed demonstrated higher concentrations of serum C2C (r = -0.52, P = 0.02), while there was no significant association between walking speed and aggrecan concentrations (ρ = -0.29, P = 0.31). After accounting for the variance associated with stance phase duration, ACLR individuals with a slower walking speed still demonstrated greater serum C2C concentrations (partial r = -0.53, P = 0.02).

CONCLUSION

ACLR individuals who habitually walk slower may experience a greater degree of collagen breakdown, suggesting that walking speed may be a future useful clinical indicator for identifying individuals with higher levels of cartilage breakdown and preradiographic osteoarthritic joint changes.

Dietary Fat Intake and Radiographic Progression of Knee Osteoarthritis: Data From the Osteoarthritis Initiative

OBJECTIVE

Few studies have investigated the role of dietary factors on knee osteoarthritis (OA) progression. We examined the prospective association of dietary fat intake with radiographic progression of knee OA.

METHODS

In the Osteoarthritis Initiative, 2,092 participants with radiographic knee OA and having baseline dietary data were followed at yearly intervals up to 48 months. Dietary intakes of fatty acids were assessed with the Block Brief Food Frequency Questionnaire. To evaluate radiographic progression of knee OA, we used quantitative joint space width (JSW) between the medial femur and tibia of the knee based on fixed-flexion posteroanterior radiographs. Linear mixed models for repeated measures were used to test the association between dietary fat and JSW loss over time.

RESULTS

We observed significant positive relationships of total fat and saturated fatty acids (SFA) intakes with JSW loss. With increasing quartiles of total fat intake, JSW decreases over 48 months were 0.26 mm, 0.27 mm, 0.31 mm and 0.35 mm, respectively (P = 0.02 for trend). Similar association was observed between SFA intake and JSW loss. In contrast, higher intakes of mono- (MUFA) and polyunsaturated fatty acids (PUFA), and higher ratio of PUFA to SFA were associated with a reduced JSW loss.

CONCLUSION

High intakes of total fat and SFA may be associated with increased structural knee OA progression, while MUFA and PUFA may reduce radiographic progression. Replication of these novel findings in other prospective studies is needed to confirm if reduction in SFA intake and increase in unsaturated fat intake lead to delayed knee OA progression.

Prevalence of Radiographic Knee Osteoarthritis After Anterior Cruciate Ligament Reconstruction, With or Without Meniscectomy: An Evidence-Based Practice Article

Reference:  Claes S, Hermie L, Verdonk R, Bellemans J, Verdonk P. Is osteoarthritis an inevitable consequence of anterior cruciate ligament reconstruction? A meta-analysis. Knee Surg Sports Traumatol Arthrosc. 2013;21(9):1967-1976.

CLINICAL QUESTION

  What is the prevalence of radiographic knee osteoarthritis (OA) at a mean follow-up equal to or greater than 10 years after autologous anterior cruciate ligament (ACL) reconstruction, with or without meniscectomy?

DATA SOURCES

  The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines were used to conduct this meta-analysis. Studies were identified by searching PubMed, MEDLINE, EMBASE, and Cochrane Library dating from their earliest file until October 2010. Key terms applied for searching were anterior cruciate ligament or ACL, autologous, follow-up, long-term, outcome, reconstruction, results, treatment, and (osteo)arthritis or osteoarthrosis. The reference lists of included studies were also manually checked to ensure that relevant articles were not omitted.

STUDY SELECTION

  The authors limited their search to English- and French-language journals. Included studies provided radiographic outcomes after autologous ACL reconstruction and had a mean follow-up of ≥10 years. Excluded studies evaluated ACL reconstruction with major concomitant surgical procedures (eg, meniscal allograft transplantation, high tibial osteotomy). In addition, data from 2 studies completed by the same research team with identical patient populations were limited to the article with the longest follow-up. Finally, manuscripts with inaccurate or incomplete data were excluded.

DATA EXTRACTION

  The following key characteristics of each study were extracted: type of study (prospective or retrospective); ACL surgical procedure (eg, open or arthroscopic bone-patellar tendon-bone graft); time frame of surgery; mean follow-up (in years) post-ACL reconstruction; total number of participants with radiographs; total number of participants with radiographic OA at follow-up; and number of participants with meniscectomy before, during, or after ACL reconstruction. Although the OA diagnosis was based on radiographic criteria, the included studies used 4 OA classifications and grading scales: Ahlbäck, Fairbanks, Kellgren and Lawrence, and International Knee Documentation Committee. Regardless of classification or grading scale, OA was defined as the presence of joint-space narrowing: Ahlbäck grades 1 through 5, modified Fairbanks grades 2 and 3, Kellgren and Lawrence ≥2, and International Knee Documentation Committee grades C and D. Tibiofemoral and patellofemoral OA data were collapsed due to the lack of reporting specificity among the studies. Participants were categorized into a meniscectomy or nonmeniscectomy group if this information was reported. Partial or total meniscectomies before, during, or after ACL reconstruction were collapsed regardless of location (medial or lateral compartment), and those patients who underwent a meniscal repair were grouped into the nonmeniscectomy group. Data were analyzed using odds ratios, the Cochran χ2 test, and a random-effects meta-regression analysis. The DerSimonian and Laird approach was used to assess study heterogeneity. P values below .05 were considered statistically significant.

MAIN RESULTS

  The initial computerized database search resulted in 211 possible studies. However, after the authors applied the inclusionary and exclusionary criteria, only 16 studies were relevant. A total of 1554 participants were available at the follow-up period. Mean follow-up ranged from 10 to 24.5 years; 11 of the 16 articles had a mean follow-up between 10 and 12 years. Heterogeneity was large (I2 = 96%), which indicated that the included studies generated a wide range of knee OA prevalence (2%-79%). Almost 28% (95% confidence interval [CI] = 16.3%, 43.5%) of participants had radiographic knee OA. A total of 1264 participants were involved in studies that evaluated meniscectomies (n = 11). Among the 614 participants with either partial or total meniscectomies, 50.4% had radiographic knee OA (95% CI = 27.4%, 73.1%). In contrast, only 16.4% (95% CI = 7.0%, 33.9%) of those without a meniscectomy had radiographic knee OA.

CONCLUSIONS

  The findings of Claes et al reflected a radiographic knee OA prevalence at a minimum average of 10 years' postautologous ACL reconstruction that was lower than commonly perceived (up to 79%). In addition, meniscectomy was an important risk factor (3.54-fold increase) for developing OA after ACL reconstruction.

Posttraumatic Bone Marrow Lesion Volume and Knee Pain Within 4 Weeks After Anterior Cruciate Ligament Injury

CONTEXT

  After an anterior cruciate ligament (ACL) injury, a majority of patients have a traumatic bone marrow lesion (BML, or bone bruise). The clinical relevance of posttraumatic lesions remains unclear.

OBJECTIVE

  To explore the cross-sectional associations between traumatic BML volume and self-reported knee pain and symptoms among individuals within 4 weeks of ACL injury.

DESIGN

  Cross-sectional exploratory analysis of a randomized clinical trial.

SETTING

  Orthopaedic departments at 2 hospitals in Sweden.

PATIENTS OR OTHER PARTICIPANTS

  As part of a randomized trial (knee anterior cruciate ligament nonoperative versus operative treatment [KANON] study), 121 young active adults (74% men, age = 26 ± 5 years, height = 1.8 ± 0.1 m, weight = 76 ± 13 kg) with an ACL tear were studied.

MAIN OUTCOME MEASURE(S)

  The BML volume in the proximal tibia and distal femur was segmented using magnetic resonance images obtained within 4 weeks of injury. A radiologist evaluated the presence of depression fractures on the images. Pain and symptoms of the injured knee (Knee Injury and Osteoarthritis Outcome Score [KOOS] pain and symptoms subscales) were obtained the same day as imaging. We used linear regression models to assess the associations.

RESULTS

  Most knees had at least 1 BML (96%), and the majority (57%) had a depression fracture. Whole-knee BML volume was not related to knee pain for the entire cohort (β = -0.09, P = .25). Among those without a depression fracture, larger whole-knee BML volume was associated with increased knee pain (β = -0.46, P = .02), whereas no association was found for those with a depression fracture (β = 0.0, P = .96). Larger medial (β = -0.48, P = .02) but not lateral (β = -0.03, P = .77) tibiofemoral BML volume was associated with greater pain. We found no association between BML volume and knee symptoms.

CONCLUSIONS

  We confirmed the absence of relationships between whole-knee BML volume and pain and symptoms within 4 weeks of ACL injury. Our findings extend previous reports in identifying weak associations between larger BML volume in the medial compartment and greater pain and between BML volume and greater pain among those without a depression fracture.

The Role of Athletic Trainers in Preventing and Managing Posttraumatic Osteoarthritis in Physically Active Populations: a Consensus Statement of the Athletic Trainers' Osteoarthritis Consortium

OBJECTIVE

  To provide athletic trainers with a fundamental understanding of the pathogenesis and risk factors associated with the development of posttraumatic osteoarthritis (PTOA) as well as the best current recommendations for preventing and managing this condition.

BACKGROUND

  Posttraumatic osteoarthritis, or osteoarthritis that develops secondary to joint injury, accounts for approximately 5.5 million US cases annually. A young athlete with a joint injury is at high risk for PTOA before the age of 40, which could lead to the patient living more than half of his or her life with a painful and disabling disorder. Given our frequent contact with physically active people who often sustain traumatic joint injuries, athletic trainers are in a unique position to help prevent and manage PTOA. We can, therefore, regularly monitor joint health in at-risk patients and implement early therapies as necessary.

RECOMMENDATIONS

  The recommendations for preventing and managing PTOA are based on the best available evidence. Primary injury prevention, self-management strategies, maintenance of a healthy body weight, and an appropriate level of physical activity should be encouraged among those at risk for PTOA after acute traumatic joint injury. Education of athletic trainers and patients regarding PTOA is also critical for effective prevention and management of this disease.

Systolic and pulse pressure associate with incident knee osteoarthritis: data from the Osteoarthritis Initiative

We evaluated the relationship of systolic blood pressure, diastolic blood pressure, pulse pressure, and treatment with antihypertensives with knee osteoarthritis incidence in a US cohort. We performed a longitudinal study (2004-2010) nested within the Osteoarthritis Initiative Study including only individuals without knee osteoarthritis at baseline. Systolic blood pressure, diastolic blood pressure, and pulse pressure were assessed at baseline, 12-, 24-, and 36-month visits. Knee radiographs at baseline, 12-, 24-, 36- and 48-month visits defined radiographic osteoarthritis, Kellgren and Lawrence grade ≥2. We performed logistic regression, adjusting for age, sex, body mass index, NSAID use, number of antihypertensive medications, diabetic medications, and cholesterol medications. One thousand nine hundred and thirty people (6040 observations) were included. Annual incidence rates of radiographic osteoarthritis by systolic blood pressure quartiles (lowest to highest) were 2.1, 3.4, 3.7, and 3.7%. Fully adjusted odds ratios of incident radiographic osteoarthritis (OA) for the 2nd-4th quartiles were 1.6, 1.7, and 1.6 relative to the lowest quartile (p for trend = 0.03). Pulse pressure results were similar. There was no association with diastolic blood pressure. Compared to those not taking any antihypertensive medications, those taking ≥3 had decreased odds (0.4, 0.1-1.0) of developing incident OA. In a US cohort, higher systolic blood pressure and pulse pressure are associated with increased incidence of radiographic knee osteoarthritis while treatment with ≥3 antihypertensive medications was associated with reduced incidence. These findings suggest a new and promising avenue for research on disease modification in knee osteoarthritis.

Mindfulness Is Associated With Treatment Response From Nonpharmacologic Exercise Interventions in Knee Osteoarthritis

OBJECTIVE

To examine the association between baseline mindfulness and response from exercise interventions in knee osteoarthritis (OA).

DESIGN

Cohort study; responder analysis of a clinical trial subset.

SETTING

Urban tertiary care academic hospital.

PARTICIPANTS

Participants with symptomatic, radiographic knee OA (N=86; mean age, 60y; 74% female; 48% white).

INTERVENTIONS

Twelve weeks (twice per week) of Tai Chi or physical therapy exercise.

MAIN OUTCOME MEASURES

Treatment response was defined using Osteoarthritis Research Society International criteria indicating meaningful improvements in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain, WOMAC function, or Patient Global Assessment scores. At baseline, participants completed the Five Facet Mindfulness Questionnaire (mean total score, 142±17) and were grouped into 3 categories of total mindfulness: higher, medium, or lower. Relative risk (RR) ratios were used to compare treatment response across groups.

RESULTS

Participants with higher total mindfulness were 38% (95% confidence interval [CI], 1.05-1.83) more likely to meet responder criteria than those with lower mindfulness. We found no significant difference between medium and lower mindfulness groups (RR=1.0; 95% CI, 0.69-1.44). Among the 5 mindfulness facets, medium acting-with-awareness was 46% (95% CI, 1.09-1.96) more likely to respond than lower acting-with-awareness, and higher acting-with-awareness was 34% more likely to respond, but this did not reach significance (95% CI, 0.97-1.86).

CONCLUSIONS

In this study, higher mindfulness, primarily driven by its acting-with-awareness facet, was significantly associated with a greater likelihood of response to nonpharmacologic exercise interventions in knee OA. This suggests that mindfulness-cultivating interventions may increase the likelihood of response from exercise.

Development of a clinical prediction algorithm for knee osteoarthritis structural progression in a cohort study: value of adding measurement of subchondral bone density

Background

Risk prediction algorithms increase understanding of which patients are at greatest risk of a harmful outcome. Our goal was to create a clinically useful prediction algorithm for structural progression of knee osteoarthritis (OA), using medial joint space loss as a proxy; and to quantify the benefit of including periarticular bone mineral density (BMD) in the algorithm.

Methods

Participants were from the Osteoarthritis Initiative (OAI) Progression Cohort, with X-ray readings of medial joint space at 36- and 48-month visits, and a 30- or 36-month medial-to-lateral tibial BMD ratio (M:L BMD ratio) value. Loss of medial joint space was the outcome and clinically available factors associated with OA progression were employed in the base prediction algorithm, with M:L BMD ratio added to an enhanced prediction algorithm. The benefit of adding M:L BMD ratio was evaluated by change in area under the ROC curve (AUC), net reclassification improvement (NRI), and integrated discrimination improvement (IDI).

Results

Five hundred thirty-three participants were included; 51 (14%) had medial joint space loss; 47% were female; the mean (SD) age was 64.6 (9.2) years and BMI was 29.6 (4.8) kg/m². The base algorithm model included age, BMI, gender, recent injury, knee pain, and hand OA as predictors and had an AUC value of 0.65. The algorithm adding M:L BMD ratio had an AUC value of 0.73, and the AUC, NRI and IDI were all significantly improved (p ≤ 0.002).

Conclusions

This clinical prediction algorithm predicts structural progression in individuals with OA using only clinically available predictors supplemented by the M:L BMD ratio, a biomarker that could be made available at clinical sites.

Effect of Intra-articular Triamcinolone vs Saline on Knee Cartilage Volume and Pain in Patients With Knee Osteoarthritis: A Randomized Clinical Trial

IMPORTANCE

Synovitis is common and is associated with progression of structural characteristics of knee osteoarthritis. Intra-articular corticosteroids could reduce cartilage damage associated with synovitis but might have adverse effects on cartilage and periarticular bone.

OBJECTIVE

To determine the effects of intra-articular injection of 40 mg of triamcinolone acetonide every 3 months on progression of cartilage loss and knee pain.

DESIGN, SETTING, AND PARTICIPANTS

Two-year, randomized, placebo-controlled, double-blind trial of intra-articular triamcinolone vs saline for symptomatic knee osteoarthritis with ultrasonic features of synovitis in 140 patients. Mixed-effects regression models with a random intercept were used to analyze the longitudinal repeated outcome measures. Patients fulfilling the American College of Rheumatology criteria for symptomatic knee osteoarthritis, Kellgren-Lawrence grades 2 or 3, were enrolled at Tufts Medical Center beginning February 11, 2013; all patients completed the study by January 1, 2015.

INTERVENTIONS

Intra-articular triamcinolone (n = 70) or saline (n = 70) every 12 weeks for 2 years.

MAIN OUTCOMES AND MEASURES

Annual knee magnetic resonance imaging for quantitative evaluation of cartilage volume (minimal clinically important difference not yet defined), and Western Ontario and McMaster Universities Osteoarthritis index collected every 3 months (Likert pain subscale range, 0 [no pain] to 20 [extreme pain]; minimal clinically important improvement, 3.94).

RESULTS

Among 140 randomized patients (mean age, 58 [SD, 8] years, 75 women [54%]), 119 (85%) completed the study. Intra-articular triamcinolone resulted in significantly greater cartilage volume loss than did saline for a mean change in index compartment cartilage thickness of -0.21 mm vs -0.10 mm (between-group difference, -0.11 mm; 95% CI, -0.20 to -0.03 mm); and no significant difference in pain (-1.2 vs -1.9; between-group difference, -0.6; 95% CI, -1.6 to 0.3). The saline group had 3 treatment-related adverse events compared with 5 in the triamcinolone group and had a small increase in hemoglobin A1c levels (between-group difference, -0.2%; 95% CI, -0.5% to -0.007%).

CONCLUSIONS AND RELEVANCE

Among patients with symptomatic knee osteoarthritis, 2 years of intra-articular triamcinolone, compared with intra-articular saline, resulted in significantly greater cartilage volume loss and no significant difference in knee pain. These findings do not support this treatment for patients with symptomatic knee osteoarthritis.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01230424.

Outcome Expectations and Osteoarthritis: Association of Perceived Benefits of Exercise With Self-Efficacy and Depression

OBJECTIVE

Outcome expectancy is recognized as a determinant of exercise engagement and adherence. However, little is known about which factors influence outcome expectations for exercise among people with knee osteoarthritis (OA). This is the first study to examine the association of outcome expectations for exercise with demographic, physical, and psychosocial outcomes in individuals with knee OA.

METHODS

We performed a cross-sectional analysis of the baseline data from a randomized trial of tai chi versus physical therapy in participants with symptomatic knee OA. Knee pain was evaluated using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Outcome expectations for exercise, self-efficacy, depression, anxiety, stress, and social support were measured using standard instruments. Logistic regression models were utilized to determine associations with outcome expectations.

RESULTS

There were 262 participants, with a mean age of 59.8 years and a mean body mass index of 32.1 kg/m2 ; 69.1% of the participants were female, 51.5% were white, the mean disease duration was 8.6 years, and the mean WOMAC knee pain and function scores were 260.8 and 906.8, respectively. Higher outcome expectations for exercise were associated with greater self-efficacy (odds ratio [OR] 1.25 [95% confidence interval (95% CI) 1.11-1.41]; P = 0.0004), as well as with fewer depressive symptoms (OR 0.84 for each 5-point increase [95% CI 0.73-0.97]; P = 0.01). Outcome expectancy was not significantly associated with sex, race, education, pain, function, radiographic severity, social support, anxiety, or stress.

CONCLUSION

Our results suggest significant associations between outcome expectations for exercise and self-efficacy and depression. Future studies should examine how these relationships longitudinally affect long-term clinical outcomes of exercise-based treatment for knee OA.

Physical activity levels and quality of life relate to collagen turnover and inflammation changes after running

The purpose of this study was to determine whether an association existed between self-reported symptom and function scores and tissue turnover or inflammatory biomarker changes after a running bout among individuals with and without an acute knee-injury history. A pre-test/post-test prospective cohort study design (Level II) of 22 participants was conducted. Eleven physically active individuals with a history of anterior cruciate ligament surgery and/or meniscus surgery within 4 years of study participation were matched to 11 healthy control participants. All participants completed self-reported outcome measures (Knee Osteoarthritis Outcomes Score and Tegner activity level) assessing knee symptoms and functional levels prior to the run. Blood samples were taken both pre- and post-30-minute run at a prescribed pace on a treadmill to determine serum biomarker concentration changes. Tegner activity levels were inversely related to type II collagen/type II collagen synthesis marker ratio biomarker changes after the run (r = -0.45, p = 0.01). Quality-of-life scores pre-exercise were inversely related to interleukin-1β changes after the run (r = -0.50, p = 0.02). No other correlation coefficients were statistically significant (r = -0.39 to 0.36). Ultimately, individuals with lower activity and quality-of-life scores experienced greater increases in collagen turnover and inflammation after a running bout, respectively. A gradual increase in activity (e.g., frequency, duration, intensity) may be warranted in this group prior to returning to activities that involve running. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:612-617, 2017.

Sex differences in the association of skin advanced glycation endproducts with knee osteoarthritis progression

Background

The accumulation of advanced glycation endproducts in articular cartilage has been suggested as an etiologic factor in the development and progression of knee osteoarthritis (KOA).

Methods

We conducted a prospective cohort study of skin advanced glycation endproducts (sAGEs) measured non-invasively by skin intrinsic fluorescence and the relationship between sAGE KOA progression in 160 men and 287 women in a sub-cohort of the Osteoarthritis Initiative at a single site. KOA progression was measured by yearly changes in Osteoarthritis Research Society International (OARSI)-defined joint space narrowing (JSN) and by yearly changes in joint space width (JSW) from baseline to 48 months. Sex-stratified repeated measures, mixed models to account for correlation between the knees within persons and adjusted for age, body mass index (BMI), Kellgren-Lawrence (KL) grade, beam angle and rim-to-rim distance were utilized.

Results

Increasing tertiles of sAGE measured at 36 months were associated with greater JSN over 4 years in men but not in women. The percentage of knees with JSN at 48 months, by tertiles of sAGE, were 7.0%, 16.0% and 17.7% in men (p for linear trend = 0.03) and 11.4%, 14.4% and 8.4% in women (p for linear trend = 0.33). Using change in JSW as the outcome, a similar trend was found in men but it was not statistically significant in fully adjusted models and no association was found in women.

Conclusion

This study provides preliminary evidence that sAGEs independent of age and BMI, are associated with knee JSN in men but not in women.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1226-z) contains supplementary material, which is available to authorized users.

Knee symptoms among adults at risk for accelerated knee osteoarthritis: data from the Osteoarthritis Initiative

The purpose of this study was to examine if adults who develop accelerated knee osteoarthritis (KOA) have greater knee symptoms with certain activities than those with or without incident common KOA. We conducted a case-control study using data from baseline and the first four annual visits of the Osteoarthritis Initiative. Participants had no radiographic KOA at baseline (Kellgren-Lawrence (KL) <2). We classified 3 groups as follows: (1) accelerated KOA: > = 1 knee developed advance-stage KOA (KL = 3 or 4) within 48 months, (2) common KOA: > = 1 knee increased in radiographic severity (excluding those with accelerated KOA), and (3) no KOA: no change in radiographic severity by 48 months. We focused on individual items from the WOMAC pain/function subscales and KOOS pain/symptoms subscales. The index visit was a year before a person met the definition for accelerated, common, or no KOA. To examine group difference in knee symptoms, we used ordinal logistic regression models for each symptom. Results are reported as odds ratios (OR) and 95% confidence intervals (CI). Individuals who developed accelerated KOA were more likely to report greater difficulty with lying down (OR = 2.10, 95% CI = 1.04 to 4.25), pain with straightening the knee fully (OR = 2.04, 95% CI = 1.08, 3.85), and pain walking (OR = 2.49, 95% CI = 1.38, 4.84) than adults who developed common KOA. Individuals who develop accelerated KOA report greater symptoms with certain activities than those with common KOA. Our results may help identify individuals at risk for accelerated KOA or with early-stage accelerated KOA.

Is There an Association Between a History of Running and Symptomatic Knee Osteoarthritis? A Cross-Sectional Study From the Osteoarthritis Initiative

OBJECTIVE

Regular physical activity, including running, is recommended based on known cardiovascular and mortality benefits. However, controversy exists regarding whether running can be harmful to knees. The purpose of this study is to evaluate the relationship of running with knee pain, radiographic osteoarthritis (OA), and symptomatic OA.

METHODS

This was a retrospective cross-sectional study of Osteoarthritis Initiative participants (2004-2014) with knee radiograph readings, symptom assessments, and completed lifetime physical activity surveys. Using logistic regression, we evaluated the association of history of leisure running with the outcomes of frequent knee pain, radiographic OA, and symptomatic OA. Symptomatic OA required at least 1 knee with both radiographic OA and pain.

RESULTS

Of 2,637 participants, 55.8% were female, the mean ± SD age was 64.3 ± 8.9 years, and the mean ± SD body mass index was 28.5 ± 4.9 kg/m2 ; 29.5% of these participants ran at some time in their lives. Unadjusted odds ratios of pain, radiographic OA, and symptomatic OA for those prior runners and current runners compared to those who never ran were 0.83 and 0.71 (P for trend = 0.002), 0.83 and 0.78 (P for trend = 0.01), and 0.81 and 0.64 (P for trend = 0.0006), respectively. Adjusted models were similar, except radiographic OA results were attenuated.

CONCLUSION

There is no increased risk of symptomatic knee OA among self-selected runners compared with nonrunners in a cohort recruited from the community. In those without OA, running does not appear to be detrimental to the knees.